CN114111566A

CN114111566A - Surveying device, surveying system, and moving body operation method

Info

Publication number: CN114111566A
Application number: CN202110538156.5A
Authority: CN
Inventors: 大西义人; 岩本晃; 齐藤勇来; 近藤健史; 大沼直人
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2020-08-28
Filing date: 2021-05-18
Publication date: 2022-03-01
Anticipated expiration: 2041-05-18
Also published as: JP2022039414A; JP7453883B2; CN114111566B

Abstract

The measuring device, the measuring system and the moving object operating method of the present invention measure the absolute position of the moving object on the moving path with high speed and high accuracy. The measurement system includes: a light transmitting unit that transmits light irradiating a stationary structure in a moving path in response to a gate signal; an imaging unit that images scattered light from the stationary structure on an imaging surface; and acquires an optical signal imaged on the imaging surface an image processing unit that calculates information related to the absolute position of the moving body (car) based on a captured image generated from the electrical signal converted by the image capturing unit, the image processing unit executes when the Marker recognition processing for determining a reference line indicating a reference for the absolute position of the marker by using the change in brightness and darkness in the second direction perpendicular to the first direction in the captured image when the marker is included in the captured image, and calculating the moving object from The movement amount calculation process of the movement amount from the reference line determined by the marker recognition process.

Description

Surveying device, surveying system, and moving body operation method

Technical Field

The present invention relates to a surveying device, a surveying system, and a moving body traveling method, and is preferably applied to a surveying device, a surveying system, and a moving body traveling method for calculating information related to movement of a moving body such as an elevator car.

Background

Conventionally, in an elevator having a car (hereinafter referred to as an "elevator car" or "car") as a moving body, a governor rope is used as a safety device for monitoring the position of the elevator car, the moving speed of the elevator car, and the like.

In recent years, a sensor (hereinafter referred to as "position/movement speed sensor") that measures the position and movement speed of the elevator car in a non-contact manner instead of the governor rope has been known. For example, patent document 1 discloses an optical position/movement speed sensor that measures the position and movement speed of an elevator car by imaging a structure present in a hoistway with an image sensor provided in the elevator car. In the non-contact position moving speed sensor, since an elongated structure such as a governor rope is not required, there is an effect of improving mountability and maintainability, and there is an effect of preventing measurement errors due to sliding.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2019-239536

Disclosure of Invention

Technical problem to be solved by the invention

However, when the elevator car is running, the measuring device for detecting the position and moving speed of the elevator car needs to detect that the car is safely stopped at the door zone in the hoistway, and control so that the door opening and closing device does not operate when the car is outside the door zone. However, the above-described conventional optical position/movement speed sensor measures a movement distance relatively based on a time difference of an image of a structure captured by an image sensor, and can detect a reference position only by combining with another structure independent of the movement distance. Therefore, there are the following problems: it is difficult to measure the absolute position of a reference position provided in a hoistway at high speed and with high accuracy from above an elevator car moving at high speed.

The present invention has been made in view of the above, and provides a measuring apparatus, a measuring system, and a moving body operating method capable of measuring an absolute position of a moving body on a moving path at high speed and with high accuracy.

Means for solving the problems

In order to solve the above problem, the present invention provides a measuring apparatus which is provided to a movable body moving on a moving path and measures a position of the movable body, the measuring apparatus including: a light transmitting unit that transmits light for irradiating a stationary structure arranged in a first direction parallel to a moving direction of the moving body on the moving path in response to a strobe signal generated at a predetermined cycle; an imaging unit that images scattered light from the stationary structure generated by the light on a shooting surface; an imaging unit that acquires an optical signal of the scattered light imaged on the imaging surface within an exposure time specified by the gate signal and converts the optical signal into an electric signal; and an image processing unit that generates the gate signal at the predetermined cycle, performs image processing on the electric signal converted by the imaging unit to generate a captured image, and calculates information on an absolute position of the moving object based on the captured image, the image acquisition unit including: a mark recognition process of, when an image of a mark provided on the stationary structure is included in the captured image, determining a reference line indicating a reference of an absolute position of the mark by using a brightness change in light and dark in a second direction perpendicular to the first direction in the captured image; and a moving amount calculation process of calculating a moving amount of the moving body from the reference line determined by the mark recognition process.

Further, in order to solve the above-mentioned problems, the present invention provides a measurement system that measures a position of a mobile body moving on a moving path, the measurement system including: a measuring device provided on the movable body; and at least one mark provided at predetermined intervals in the first direction on a stationary structure disposed in the first direction parallel to the moving direction of the moving body on the moving path. In the measuring system, the measuring device includes: a light transmitting unit that transmits light for irradiating a stationary structure arranged in a first direction parallel to a moving direction of the moving body on the moving path in response to a strobe signal generated at a predetermined cycle; an imaging unit that images scattered light from the stationary structure generated by the light on a shooting surface; an imaging unit that acquires an optical signal of the scattered light imaged on the imaging surface within an exposure time specified by the gate signal and converts the optical signal into an electric signal; and an image processing unit that generates the gate signal at the predetermined cycle, performs image processing on the electric signal converted by the imaging unit to generate a captured image, and calculates information on an absolute position of the moving object based on the captured image, the image processing unit including: a mark recognition process of, when an image of any one of the marks is included in the captured image, determining a reference line indicating a reference of an absolute position of the mark using a brightness change in light and dark in a second direction perpendicular to the first direction in the captured image; and a movement amount calculation process of calculating a movement amount of the movable body from the reference line determined by the mark recognition process.

In order to solve the above problem, the present invention provides a moving body traveling method performed by an elevator system for returning an elevator car to a nearby floor as follows. Here, the elevator system includes: a mark provided at least one between floors in a first direction on a stationary structure disposed in a first direction parallel to a moving direction of the elevator car in a hoistway; a measuring device provided on the elevator car, which photographs the stationary structure and calculates position information of the mark when the photographed image includes the image of the mark; an elevator control unit that controls an operation of the elevator car; and floor height information indicating the marks and position information of the floors for the marks corresponding to each of the floors. Further, the mobile body operation method includes: a first step of moving the elevator car to the mark in the vicinity by the elevator control unit; a second step of calculating, by the measuring device, position information of the mark from the captured image of the mark at the destination of movement in the first step; a third step of calculating, by the elevator control unit, a moving distance from the marker to the floor based on the position information of the marker calculated in the second step and the floor height table; and a fourth step of moving the elevator car by the elevator control unit by the movement distance calculated in the third step.

Effects of the invention

According to the present invention, the absolute position of the moving body on the moving path can be measured at high speed and with high accuracy.

Drawings

Fig. 1 is a diagram showing a configuration example of an elevator system 10 according to embodiment 1 of the present invention.

Fig. 2 is a diagram showing a configuration example of the measurement system 100.

Fig. 3 is a diagram showing an example of the internal configuration of the image processing unit 240.

Fig. 4 is a flowchart showing an example of processing procedures of the measurement processing by the image processing unit 240.

Fig. 5 is a diagram for explaining a change in the captured image when the car 120 moves.

Fig. 6 is a diagram showing one example of a timing chart of the gate signal transmitted to the imaging section 230 by the control section 310.

Fig. 7 is a diagram illustrating an example of the luminance distribution of a captured image in the exposure time.

Fig. 8 is a diagram showing a specific example of the luminance mark 150.

Fig. 9 is a diagram showing an example of the luminance distribution of the captured image of the luminance mark 151.

Fig. 10 is a diagram for explaining a dimensional relationship between the brightness mark 150 and the imaging region of the measuring device 110.

Fig. 11 is a conceptual diagram for explaining a procedure of return operation control of the elevator car 120.

Fig. 12 is a diagram showing a measuring apparatus 1200 according to embodiment 2 of the present invention, centering on an example of the internal configuration of an imaging unit 1220.

Fig. 13 is a diagram illustrating a measuring apparatus 1300 according to embodiment 3 of the present invention, centering on an example of the internal configuration of the imaging unit 1320.

Fig. 14 is a diagram illustrating a measuring apparatus 1400 according to embodiment 4 of the present invention, centering on an example of the internal configuration of an imaging unit 1420.

Fig. 15 is a diagram showing a configuration example of a measurement system 1500 according to embodiment 5 of the present invention.

Fig. 16 is a diagram showing a configuration example of a vehicle positioning system 1600 in which the measurement device 110 is applied to a vehicle.

Fig. 17 is a diagram showing a configuration example in which the measuring device 110 is applied to a crane positioning system 1700 of a crane.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In each embodiment of the present invention described in detail below, an apparatus, a system, and a method are explained which recognize a reference position set on a path (moving path) using a measurement system configured to include a measurement apparatus set on a moving body and a brightness mark arranged on the path guiding the moving body, and measure an absolute position of the moving body specified by the reference position at high speed and with high accuracy. However, the present invention is not limited to the embodiments described below.

The measurement device shown in each embodiment is placed on the upper portion of the mobile body, and measures information related to the movement of the mobile body (specifically, the absolute position of the mobile body, the moving speed of the mobile body, the acceleration of the mobile body, the vibration of the mobile body, and the like). For example, the measurement device irradiates (transmits) light from a light transmission unit of the mobile body to the surface of a stationary structure as an object in response to a strobe signal generated in a control unit. Then, the measuring device causes light (light that can include regular reflection light and diffuse reflection light, hereinafter referred to as "scattered light") that bounces off the surface of the stationary structure to enter the imaging surface of the imaging unit via the imaging unit, and the imaging unit photoelectrically converts the optical signal into an electrical signal. Then, the measuring device measures information about the reference position (specifically, presence or absence of a luminance mark as a reference, a reference position that the luminance mark has, an ID for distinguishing the reference position assigned to each luminance mark, and the like) in the mark identifying section based on an image generated from the converted electric signal. Further, the measurement device measures information related to the movement of the moving body (specifically, a movement distance from a reference position of the moving body, a movement speed of the moving body, vibration of the moving body, and the like) in the image processing section based on an image generated from the converted electric signal. Then, the measurement device calculates information on the absolute position of the mobile body on the movement path based on the information on the reference position and the information on the movement of the mobile body, and transmits the calculated information to a mobile body control unit for performing operation control of the mobile body or control of the safety device. Then, the moving body control unit performs operation control of the moving body and control of the safety device based on the information of the absolute position of the moving body calculated by the measuring device.

In some embodiments, an elevator car is described as an example of a moving body provided with the measuring device of the present invention, but the moving body to which the present invention can be applied is not limited to an elevator car. The techniques described in the respective embodiments can also be applied to a moving body (e.g., an automatic door, a train, a vehicle, a crane, etc.) that moves along a stationary structure (e.g., a rail, a route, a road, etc.) having scratches by artificial polishing. In the present specification, "light" refers to electromagnetic waves, and specifically, microwaves, terahertz waves, infrared rays, ultraviolet rays, X-rays, and the like can be used in addition to visible light. Likewise, the measuring system to which the present invention can be applied is not limited to a measuring system incorporated into an elevator system, and can be applied to, for example, a positioning system of a vehicle that controls automatic running, a positioning system of a crane, and the like.

In the following description, when the description is made without distinguishing between different types of elements, a common part (part other than the branch number) of the reference numerals including the branch number may be used, and when the description is made with distinguishing between different types of elements, a reference numeral including the branch number may be used. For example, when the imaging region is described without being particularly distinguished, the "brightness mark 150" is described, whereas when the measurement units (imaging regions) are described separately, the "brightness mark 150-1" or the "brightness mark 150-2" is described.

(1) Embodiment mode 1

(1-1) Structure of Elevator System 10

As shown in fig. 1, the elevator system 10 includes a measurement system 100, the measurement system 100 includes a measurement device 110 mounted on an upper portion of an elevator car 120, and the elevator car 120 is raised and lowered in a hoistway (moving path of a moving body) of a building (not shown); and a plurality of brightness markers 150 (individually, e.g., brightness markers 150-1, 150-2) provided to show reference positions within the hoistway. Further, as shown in fig. 1, the elevator system 10 includes an elevator car 120, an elevator control portion 130, or a guide rail 140, but at least any one of these constituent elements may be included in the measurement system 100.

The measuring device 110 outputs signal information (for example, signal information on the position, moving speed, acceleration, and the like of the elevator car 120) useful for controlling the operation of the elevator car 120 to the elevator control unit 130. The elevator control unit 130 controls the operation of the elevator car 120, controls safety devices, and the like. The position of the measuring device 110 is not limited to the upper part of the elevator car 120, and may be other than the upper part, for example, a side surface part, a lower part, or the like.

The guide rail 140 is an example of a stationary structure disposed in the hoistway, and is disposed in the hoistway along the moving direction of the moving body (y-axis direction in fig. 1), and is in contact with a guide roller (not shown) of the elevator car 120 to support the movement of the moving body (elevator car 120). The brightness marks 150 are disposed at predetermined intervals on the top or side of one surface (for example, a sliding surface that contacts a guide roller) of the guide rail 140, a flange surface that is fastened to a wall surface by a bolt of the guide rail 140, or a neck portion that is located at a boundary between the sliding surface and the flange surface.

The brightness mark 150 is attached in the form of a sticker, for example, but may be formed by processing the guide rail 140 by mechanical engraving or laser marking which is highly resistant to interference such as stain or rust due to aging. Alternatively, an indicator such as an LED embedded in advance in the guide rail 140 may be used for the brightness mark 150, the indicator having high brightness and being recognizable with a high S/N ratio.

Fig. 2 is a diagram showing a configuration example of the measurement system 100. As shown in fig. 2, the measuring apparatus 110 includes a light transmission unit 210, an imaging unit 220, an imaging unit 230, and an image processing unit 240. In fig. 2, the optical path is shown by a dotted line with an arrow, and the path of the electric signal is shown by a solid line with an arrow.

The light transmission unit 210 includes a light source (not shown), and is configured to irradiate the guide rail 140 as the object and the brightness mark 150 provided in the guide rail 140 with light. A temporally and spatially incoherent Light source such as an LED (Light Emitting Diode) or a halogen lamp may be used as the Light source of the Light transmission unit 210, or a temporally and spatially coherent Light source such as a laser Light source may be used as the Light source of the Light transmission unit 210.

The imaging unit 220 is configured as an optical system that images scattered light obtained by scattering, by the surface of the guide 140 or the brightness mark 150, outgoing light (outgoing light) that is light emitted from the light transmitting unit 210 toward the surface of the guide 140 or the brightness mark 150 provided in the guide 140, on the imaging surface of the imaging unit 230.

The image pickup section 230 converts an optical signal (an optical signal indicating a distribution of scattered brightness on the surface of the guide rail 140 or the surface of the brightness marker 150) from the image pickup section 220, that is, an optical signal imaged on an image pickup surface including a plurality of pixels (pixels), into an electrical signal corresponding to the brightness of the pixels, and transmits the converted electrical signal to the image processing section 240 as an image signal indicating a dark-field image. In the present embodiment, the image signal transmitted from the imaging unit 230 to the image processing unit 240 may represent not only a dark-field image but also a bright-field image, for example. For example, a CCD (Charge Coupled Device) image sensor, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like may be used for the imaging unit 230. The imaging unit 230 may be a two-dimensional area sensor or a one-dimensional line sensor having a spatial resolution function in the direction in which the car 120 ascends and descends.

In the measurement system 100, a wavelength-selective filter such as a band-pass filter may be provided in addition to the imaging unit 220 in the path of the outgoing light from the light-transmitting unit 210 and the scattered light thereof, so as to remove external light other than a desired wavelength. In the measurement system 100, for the purpose of protecting the measurement device 110, a window material or the like may be provided in the path of the incident light and the scattered light so that dust or sand does not enter the measurement device 110.

The image processing unit 240 performs predetermined image processing on the image signal (the electric signal obtained by converting the optical signal imaged on the imaging surface) received from the imaging unit 230, calculates information on the movement of the elevator car 120 (car movement-related information) and information on the reference position included in the brightness marker 150 (reference position-related information) based on the captured image generated by the image processing, and transmits the information to the elevator control unit 130. The image Processing Unit 240 may be configured by an information Processing storage medium such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or a microcontroller, or may be configured by a logic circuit element such as an FPGA (Field Programmable Gate Array).

(1-2) configuration of the image processing section 240 and measurement processing of the image processing section 240

Next, the internal configuration of the image processing unit 240 and the processing performed by the image processing unit 240 will be described in detail.

Fig. 3 is a diagram showing an example of the internal configuration of the image processing unit 240. As shown in fig. 3, the image processing unit 240 includes a control unit 310, a movement amount calculation unit 320, a brightness mark recognition unit 330, and a communication unit 340.

The control section 310 generates a plurality of strobe signals (strobe signals), transmits one of the generated strobe signals to the optical transmission section 210, and transmits the other strobe signal to the imaging section 230. The strobe signal transmitted to the optical transmission section 210 serves as a timing signal that specifies the driving time of the light source in the optical transmission section 210. The gate signal transmitted to the photographing section 230 serves as a timing signal for specifying the exposure time in the photographing section 230. Then, the control unit 310 performs predetermined image processing on the electric signal from the image pickup unit 230, and sends the image after the image processing to the movement amount calculation unit 320 and the brightness mark recognition unit 330. The image processing by the control unit 310 is specifically, for example, processing for spatially decomposing the electric signal (for example, an image signal representing a dark-field image) from the imaging unit 230 into an image corresponding to the scattering brightness distribution on the surface of the guide rail 140.

The movement amount calculation unit 320 calculates information (car movement-related information) related to the movement of the elevator car 120 based on the result of the image processing received from the control unit 310, and transmits the calculated signal information to the communication unit 340. Specifically, the car movement-related information includes information indicating, for example, the position, the movement speed, and the like of the car 120.

The brightness marker recognition unit 330 performs image recognition processing for recognizing the brightness marker 150 on the image processed from the control unit 310, calculates information (reference position-related information) on the reference position of the brightness marker 150, and transmits the calculated signal information to the communication unit 340. Specifically, the reference position-related information includes, for example, information indicating the presence or absence of the luminance mark 150 as a reference, an ID (which will be described in detail later as an "ID pattern") for identifying a reference position (reference position assigned to each luminance mark 150) that the luminance mark 150 has, and the like.

The communication unit 340 converts the car movement-related information received from the movement amount calculation unit 320 and the reference position-related information received from the brightness marker recognition unit 330 according to a communication protocol (for example, a protocol such as CAN (controller area network) communication) that CAN be received by the elevator control unit 130, and outputs the converted signal information to the elevator control unit 130.

Fig. 4 is a flowchart showing an example of the processing procedure of the measurement processing by the image processing unit 240.

According to fig. 4, the image processing section 240 starts measurement based on the gate signal generated by the control section 310, and the control section 310 acquires an image i (i) transmitted from the imaging section 230 by an electric signal for each frame i (step S101). The frame i is preferably a time which is an integral multiple of the frame period Δ t described later. Further, as described above, the image i (i) is, for example, a dark-field image. Then, in step S101, the control unit 310 stores the acquired image i (i) in a storage element (memory) in the control unit 310. The storage element for storing the image i (i) may use a volatile memory such as a register included in the image processing unit 240, or may use an externally disposed non-volatile memory.

After the process of step S101, the processes of steps S102 to S104 and the process of step S105 are executed in parallel. As described later, in step S104, the processing result of step S105 is used.

In steps S102 to S104, the movement amount calculation unit 320 calculates, for example, the position of the car 120 (the total movement amount of the car 120 from the reference position of the brightness mark 150) and the movement speed V of the car 120 as car movement-related information. The details are as follows.

First, in step S101, the movement amount calculation unit 320 reads the image I (I) of the I-th frame stored in the storage element from the storage element, reads the image I (I-k) of the I-k-th frame stored in the storage element k frames before the I-th frame (k is an integer of 1 or more) from the storage element, and calculates the movement amount Δ y of the car 120 from the I-k-th frame to the I-th frame based on the difference between the image I (I) and the image I (I-k) (step S102).

The calculation of the movement amount Δ y of the car 120 in step S102 is supplemented with a more specific image by showing an example of a captured image in fig. 5 described later.

In step S102, the image I (I-k) to be differentiated from the latest image I (I) may be selected from images before I frames (k is 1), or may be selected from images before a plurality of frames (k is an integer equal to or greater than 2). In the method of calculating the movement amount Δ y of the car 120, for example, a cross-correlation function, which is an index of similarity between the image I (I) and the image I (I-k), is calculated, and a y component (a component in the same direction as the direction in which the car 120 moves up and down) of the peak coordinate position of the cross-correlation function is estimated as the movement amount Δ y of the car 120. In addition, the method of estimating the movement amount Δ y from the y component of the peak coordinate position is not limited to a specific method. For example, the estimation may be performed based on the peak coordinates of the maximum position, or may be performed by performing least squares fitting using several points near the maximum position.

Next, the movement amount calculation unit 320 calculates the elapsed time k × Δ t from the image I (I-k) to the image I (I), and calculates the movement speed V of the car 120 by taking the ratio of the movement amount Δ y to the time k × Δ t (movement speed V ═ Δ y/(k × Δ t)) (step S103).

Further, the movement amount calculation unit 320 calculates the total movement amount of the car 120 from the reference position of the brightness marker 150, which is recognized as the reference for the movement amount calculation by the brightness marker recognition unit 330 in step S105, by sequentially adding the movement amount Δ y of the car 120 to the reference position of the brightness marker 150 in an accumulated manner (step S104).

On the other hand, in step S105, the luminance marker recognition unit 330 calculates reference position-related information using the luminance marker 150 included in the image i (i) of the i-th frame as a reference for the movement amount calculation.

More specifically, the brightness mark identifying part 330 reads the image i (i) of the i-th frame from the storage element, and determines the presence or absence of the brightness mark 150 in the image i (i) by performing image identification processing on the image i (i). When the luminance marker 150 is present in the image i (i), the luminance marker recognition unit 330 recalculates the reference position related information with the luminance marker 150 as a new reference for the movement amount calculation. Specifically, the luminance mark identification section 330 calculates a reference position of the luminance mark 150, which is newly used as a reference for the movement amount calculation, an ID (ID pattern 820 of fig. 8) assigned to the luminance mark 150, and the like. On the other hand, when the luminance marker 150 is not present in the image i (i), the luminance marker identifying part 330 does not update the reference for the movement amount calculation, and continues to use the reference position related information calculated by the latest measurement processing.

By performing the processing of step S105 in this manner, the brightness marker recognition unit 330 can calculate the reference position-related information using the latest brightness marker 150 included in the image i (i) that changes in accordance with the movement of the car 120 as a reference for the movement amount calculation. Specifically, referring to fig. 1, when the car 120 (measuring device 110) moves upward in the y-axis direction, for example, until the car 120 passes the brightness mark 150-1 and reaches the brightness mark 150-2, the brightness mark 150-1 becomes a reference for calculating the movement amount, and the reference position-related information with the brightness mark 150-1 as a reference is calculated. In addition, the brightness mark 150-2 becomes a reference for calculating the movement amount until the car 120 (the measuring device 110) reaches the next brightness mark 150 after reaching the brightness mark 150-2, and the reference position related information with the brightness mark 150-2 as a reference is calculated.

After step S104 and step S105 are completed, the control unit 310 (or the communication unit 340) transmits the car movement-related information calculated in steps S102 to S104 and the reference position-related information calculated in step S105 to the elevator control unit 130 via the communication unit 340 (step S106). Then, the control section 310 increments the value of the frame number "i" by 1 (step S107).

Then, the control unit 310 confirms whether or not the measurement device 110 is in a state of being supplied with power (step S108). When the power supply is supplied in step S108 (yes in step S108), the image processing unit 240 repeats the processing in steps S101 to S107, and when the power supply is cut off (no in step S108), the measurement processing is ended.

In the measurement processing shown in fig. 4, as described above, the luminance marker 150 (more precisely, the reference position of the luminance marker 150) whose presence is recognized by the image recognition processing of the luminance marker recognition section 330 is set as the reference position, and the amount of movement of the car 120 from the reference position is added up to recognize the absolute position between the reference positions of the car 120. Therefore, when the car is running, the error may be accumulated in a period until the reference position of the next brightness mark 150 is reached. In this case, when the car 120 travels back and forth in a section without a reference position, errors may be continuously accumulated all the time, which is undesirable in terms of measurement accuracy of the absolute position. To eliminate this accumulation of errors, at least one brightness marker 150 is placed between floors in this embodiment. Specifically, for example, when the interval between floors is 4 meters, the interval between the setting of the brightness marks 150 is set to 4 meters or less.

As described above, in the elevator system 10, by performing the measurement processing by the image processing portion 240 of the measurement system 100 (the measurement device 110), when the elevator car 120 moves, the absolute position of the elevator car 120 can be calculated by cumulatively adding the relative movement amount Δ y from the reference position of the brightness mark 150 as a reference.

Next, as a supplement to the above-described measurement process, a calculation image of the movement amount Δ y of the car 120 by the movement amount calculation unit 320 will be described with reference to fig. 5. In addition, as a supplementary explanation associated with the captured image (i)) which is the target of the measurement processing, fig. 6 and 7 explain the design of the exposure time of the imaging unit 230 for preventing the occurrence of subject shake in the captured image.

Fig. 5 is a diagram for explaining a change in the captured image when the car 120 moves. Strictly speaking, as described above, the image pickup section 230 reads the optical signal imaged on the image pickup surface and converts it into an electric signal, and the image processing section 240 (the control section 310) performs image processing on the electric signal to generate a picked-up image. However, for the sake of simplicity, in the following description, the electric signal converted by the imaging unit 230 may be processed by replacing it with a "captured image" subjected to image processing by the control unit 310. In fig. 5, the case where the image of the brightness mark 150 is not included in the captured image is illustrated as an example, but the captured image may include the image of the brightness mark 150.

When the guide rail 140 as the object is photographed from the car 120 moving at the moving speed V, as shown in fig. 5, a deviation occurs between the two photographed images 520-1 and 520-2 of the scattering luminance distribution 510 on the surface of the object (the surface of the guide rail 140) in the moving direction (y-axis direction) at the time of time t and the time of time (t + k × Δ t). Further, Δ t represents a frame period, k is an integer value, and represents the number of times of unit frames elapsed with a predetermined timing as a starting point (k equals 0). At this time, Δ y, which indicates the amount of displacement of the deviation, corresponds to the amount of movement Δ y of the car 120. Therefore, as described in steps S102 to S104 of fig. 4, the moving amount calculating unit 320 can calculate the moving amount of the car 120 by comparing the captured images of different frames.

As shown in fig. 6, the control section 310 of the image processing section 240 transmits a gate signal 610 (gate signals 610-1, 610-2 of fig. 6) to the imaging section 230 every frame period Δ t. The photographing section 230 performs exposure only for the time of the pulse width T (exposure time T) in response to the pulse of the gate signal 610 transmitted from the control section 310, and photographs the light signal imaged on the photographing surface. In the measurement device 110 of the present embodiment, the strobe signal 610 may be transmitted from the control unit 310 to the light transmission unit 210 in parallel with the transmission of the strobe signal 610 from the control unit 310 to the imaging unit 230, and the light transmission unit 210 that has received the strobe signal 610 may turn on the light source only during the exposure time T. By performing such lighting control, the average output power per unit time of the light transmitting unit 210 can be reduced, and thus the effect of suppressing the power and heat dissipation required for driving is obtained.

Fig. 7 is a diagram illustrating an example of the luminance distribution of a captured image in the exposure time. In more detail, fig. 7 shows an example of the luminance distribution of the captured image when the scattered light emitted from the luminance mark 150 provided on the guide rail 140 is imaged on the imaging section 230 during one exposure time T.

In fig. 7, the exposure time is T, and therefore, if the start time in the exposure time is T, the end time in the exposure time is represented by T + T. The scattered light brightness distribution 710-1 is a brightness distribution of scattered light on the imaging surface at a start time T within the exposure time T, and the scattered light brightness distribution 710-2 is a brightness distribution of scattered light on the imaging surface at an end time T + T within the exposure time T. As can be seen by comparing the scattered light luminance distributions 710-1 and 710-2 in fig. 7, the luminance distribution of the scattered light imaged on the light receiving surface (imaging surface) of the imaging unit 230 moves in the moving direction (y-axis direction) of the car 120 during the period of the gate signal 610 transmitted from the control unit 310 to the imaging unit 230. As a result, subject shake in the y-axis direction occurs in the captured image 720 during this period (exposure time T).

The subject shake is caused by "blurring" in the moving direction (y-axis direction) of the exposed captured image 720 because images of scattered light intensity distributions that change continuously from moment to moment are accumulated from the scattered light intensity distribution 710-1 at the start time T to the scattered light intensity distribution 710-2 at the end time T + T within the exposure time T. That is, in the captured image 720, the blur occurs only in the magnitude of V × T, which is the product of the moving speed V of the car 120 and the exposure time T, in proportion to the exposure time T in the imaging unit 230. Moreover, the following problems are conceivable: if the image processing is performed in a state where the subject is shaken (blurred) in the captured image 720, the moving speed or position of the car 120 cannot be accurately calculated.

In order to suppress the occurrence of subject shake in the moving direction (y-axis direction) of the car 120, the exposure time T needs to be sufficiently short (short) in consideration of the moving speed V of the car 120. Therefore, in the present embodiment, the spatial resolution δ of the pixel from the imaging unit 230 is set to be larger than the spatial resolution δ of the pixel_xMaximum moving speed V of car 120_maxThe time shorter (smaller) than the obtained time is set as the exposure time T of the imaging unit 230. I.e. by using the required spatial resolution delta_xAnd the maximum moving speed V of the car 120_maxTo determine the exposure time T to satisfy "T<δ_x/V_max"is used in the following description. Specifically, for example, for an elevator car 120 requiring a maximum moving speed of 300m per minute, when a spatial resolution of 0.5mm is required, it may be required to control the exposure time below 100 μ s.

(1-3) features of luminance marker 150

The following describes in detail the features of the brightness mark 150 usable in the measurement system 100 of the present embodiment.

First, the shape of the brightness mark 150 is described.

Fig. 8 is a diagram showing a specific example of the luminance mark 150. In fig. 8, as a specific example of the luminance mark 150 having a different shape, a luminance mark 151 is illustrated in fig. 8(a), a luminance mark 152 is illustrated in fig. 8(B), and a luminance mark 153 is illustrated in fig. 8 (C). The features of the respective luminance marks 151 to 153 will be described later, and the common structure of the luminance marks 150 will be described first.

As shown in each view in fig. 8, the luminance mark 150 includes a reference line 810 as a reference of an absolute position and an ID pattern 820 that distinguishes the reference position by combining a configuration of bright and dark luminance. The ID pattern 820 has an identification signal different for each pattern. Further, a margin of a predetermined amount or more is provided outside the print area of the brightness mark 150. By providing the blank space, even if the car 120 swings in the vertical direction (x-axis direction) perpendicular to the moving direction (y-axis direction) during traveling, the imaging unit 230 can recognize the brightness mark 150 without causing the print area to deviate from the imaging area. That is, in order for the imaging unit 230 to reliably converge the print area of the brightness mark 150 within the imaging area even if the car 120 swings in the x-axis direction during traveling, the length of the side of the brightness mark 150 in the x-axis direction may be equal to or less than the length obtained by subtracting the displacement amount of the maximum swing that can occur in the x-axis direction on the car 120 from the length of the side of the imaging area in the x-axis direction. Specifically, for example, when the measuring device 110 having a photographing area of 13mm is used for the car 120 capable of generating a car shake of 5mm in the x-axis direction, the length of the side of the brightness mark 150 in the x-axis direction is required to be at least 8mm or less.

The luminance marks 150 (luminance marks 151 to 153) of the present embodiment have a characteristic luminance change at least in the x-axis direction. By utilizing this luminance change, the measuring device 110 can improve the detection accuracy by suppressing the influence of the subject shake to the minimum even when the car 120 moves at a high speed in the y-axis direction. A specific example for explaining the effect of improving the detection accuracy is shown in fig. 9.

Fig. 9 is a diagram showing an example of the luminance distribution of the captured image of the luminance mark 151. Similarly to fig. 7 in which the luminance marker 150 is a target, fig. 9 shows an example of the luminance distribution of the captured image during the period of the one-shot exposure time T, with the luminance marker 151 shown as an example in fig. 8(a) being a target. As described above, in fig. 7, when the car 120 moves at a high speed, the subject may shake in the moving direction (y-axis direction) in the captured image. Specifically, in fig. 9, images of scattered light luminance distributions continuously changing from time to time are integrated from the scattered light luminance distribution 910-1 at the start time T to the scattered light luminance distribution 910-2 at the end time T + T in the exposure time T, and subject shake occurs in the moving direction (y-axis direction) of the exposed captured image 920. However, since the luminance marker 150 (for example, the luminance marker 151) of the present embodiment has a characteristic luminance change in the x-axis direction, even if the subject shakes in the moving direction (y-axis direction) of the car 120 in the captured image 920, the pattern of the luminance change (the light and shade of the edge) in the x-axis direction is not affected (see the captured image 920 in fig. 9). That is, even if subject shake occurs in the y-axis direction in the captured image 920, the measurement device 110 (image processing unit 240) can detect a bright-dark edge provided in the x-axis direction where subject shake does not occur, and therefore, the detection accuracy of the ID pattern 820 can be improved.

In the luminance mark 150 (luminance marks 151 to 153) of the present embodiment, the interval of the change in the brightness of the ID pattern 820 between light and dark is larger than the spatial resolution δ x determined by the pixels of the imaging unit 230. This is because the interval between changes in brightness and darkness in the ID pattern 820 is assumed to be larger than the spatial resolution δ determined by the pixels of the imaging unit 230_xIn the case of smaller (finer) size, the imaging unit 230 cannot distinguish the luminance change. Therefore, specifically, for example, when the spatial resolution δ of the photographing part 230_xAt 0.5mm, the period of the light and dark luminance change of the ID pattern 820 is at least more than 0.5 mm.

In addition, the combinations of the ID patterns 820 in the brightness marks 150 (the brightness marks 151 to 153) of the present embodiment have the number of combinations sufficient to distinguish the reference position information in the same hoistway. Specifically, for example, when the brightness marks 150 are provided every 4m in a hoistway having a total height of 100m, at least 25 brightness marks 150 are provided, and thus the ID pattern 820 requires at least 25 or more patterns in combination.

In the luminance marks 150 (luminance marks 151 to 153) of the present embodiment, the ID pattern 820 does not have periodicity in the moving direction (y-axis direction). This is because, even in the place where the brightness marker 150 is provided, the image processing (movement amount calculation processing) by the movement amount calculation section 320 described above is performed, and therefore, if the ID pattern 820 of the brightness marker 150 has periodicity in the movement direction (y-axis direction) of the car 120, the periodicity is reflected in the movement amount calculation processing, and an uncertainty corresponding to the periodicity appears in the calculated movement amount Δ y (and the total movement amount) of the car 120, and there is a possibility that the movement amount cannot be uniquely estimated.

Next, the features of the luminance marks 151 to 153 shown in fig. 8(a) to 8(C) will be described. Any one of these luminance marks 151 to 153 has the feature of the luminance mark 150 of the present embodiment described above.

The luminance mark 151 shown in fig. 8(a) is an example of the luminance mark 150 in which the reference line 810 and the ID pattern 820 are separated from each other, and the ID pattern 820-1 of the luminance mark 151 is formed of a one-dimensional barcode having different light and shade in the x-axis direction. In the case of the luminance mark 151, by detecting the position of the light and dark edge in the ID pattern 820-1, the information of the ID for distinguishing the reference position can be recognized. By detecting a position where the luminance difference is equal to or greater than a predetermined threshold value using the light and dark luminance difference as an index, the light and dark edge can be recognized. Similarly, the position of the reference line 810-1 can be recognized by detecting the coordinate (y coordinate) where the luminance sharply changes in the y-axis direction.

In the present embodiment, the use of the luminance mark 151 enables the luminance mark 150 of the present embodiment to have the characteristics described above, and a luminance mark having a simpler configuration to be realized.

Brightness mark 152 shown in fig. 8(B) is an example of brightness mark 150 in which reference line 810 and ID pattern 820 are integrated. The ID pattern 820-2 of the brightness mark 152 is formed of a two-dimensional light and dark mosaic pattern in the xy-axis direction, and the reference line 810-2 is formed as one side of the above-described light and dark mosaic pattern. Like the ID pattern 820-1 of the one-dimensional barcode having light and shade shown in fig. 8(a), a light and shade mosaic pattern such as the ID pattern 820-2 can be detected for light and shade by luminance difference detection, and as a result, a combination of patterns can be recognized. Further, by detecting the corner position of the rectangle of the brightness mark 152, the position of the reference line 810-2 can be determined.

In the present embodiment, when the luminance mark 152 described above is used, the number of pattern combinations can be increased in the y-axis direction even for the bright-dark mosaic type two-dimensional ID pattern 820-2 as compared with the ID pattern 820-1 formed of the one-dimensional barcode in the x-axis direction, and thus the writable information amount (for example, layer height information) can be increased. Further, even for partial pattern defects due to stains adhering to the pattern, partial peeling of the pattern, saturation of pixel values by external light, or the like, a redundant configuration of the pattern can be easily obtained by increasing the number of pattern combinations, and thus a more robust luminance mark can be realized.

Brightness mark 153 shown in fig. 8(C) is an example of brightness mark 150 in which reference line 810 and ID pattern 820 are integrated. The ID pattern 820-3 of the brightness mark 153 is composed of numerals and characters. In the case of using the brightness mark 153, before measuring the position of the car 120, the image processing section 240 learns each ID pattern 820-3 through processing such as machine learning, for example, and assigns and stores position information to the feature points of each ID pattern 820-3 obtained through the learning, so that the image processing section 240 can read information (numbers or characters) included in the ID pattern 820-3 in the captured image when measuring the position of the car 120. Further, the reference line 810-3 is configured as one side of the rectangle of the brightness mark 153, as with the reference line 810-2, and thus the position can be specified by detecting the corner position of the rectangle of the brightness mark 153.

In the present embodiment, when the brightness mark 153 as described above is used, since a person can easily recognize information included in the ID pattern 820-3 from the captured image of the brightness mark 153 of the imaging unit 230, the brightness mark 153 can be used for an application other than the object of the reading process of the measuring apparatus 110. For example, the brightness mark 153 can be used for the purpose of distinguishing the number and position of members such as the guide rail 140 at the time of installation, construction, or inspection of the guide rail 140.

In the measurement system 100 according to the present embodiment, for the purpose of improving the recognition accuracy of the brightness mark 150, in addition to the ID pattern 820 formed by the tape or the score provided manually, the ID pattern 820 may be made of dirt or a scratch naturally adhering to the guide rail 140. In this case, the dirt and the scratch may be stored in the measuring device 110 or the elevator control portion 130 in advance, and may be used by correlating the dirt and the scratch with position information thereof.

Next, the size of the luminance mark 150 is explained.

In the present embodiment, the length L of the side of the luminance mark 150 in the y-axis direction_markConfigured to pass through the imaging area of the imaging unit 230Length L of side in y-axis direction_obsSubtracting the maximum moving speed V of the moving body (car 120)_maxThe length obtained by multiplying the value by the frame time Δ t (see fig. 6) corresponding to the generation cycle of the strobe signal 610 is not more than the length obtained. Namely, is constituted as "L_mark≤L_obs-V_maxThe relation of × Δ t "holds (the equal sign of the above inequality may be excluded). With such a configuration, the image processing unit 240 can acquire the entire captured image of the luminance mark 150 in at least any one frame between two consecutive frames. The necessity of the above relation is satisfied by the size of the brightness mark 150 with reference to fig. 10.

Fig. 10 is a diagram for explaining a dimensional relationship between the brightness mark 150 and the imaging region of the measuring device 110. In fig. 10, an example is shown in which the length L of the side in the y-axis direction of the luminance mark 150_markDoes not satisfy the relation "L" shown in the previous paragraph_mark≤L_obs-V_maxIn the case of the structure of × Δ t ″, a complete captured image of the luminance mark 150 cannot be obtained in at least one frame between two consecutive frames. The image processing unit 240 (control unit 310) sets the frame period at which the electric signal of the captured image is acquired from the imaging unit 230 to Δ t.

As shown in fig. 10, when two consecutive frames (a first frame and a second frame) pass, the imaging area 1010 of the measuring device 110 (the imaging unit 230) moves in the y-axis direction, which is the moving direction of the car 120. Specifically, in fig. 10, the movement is from the photographing region 1010-1 at the first frame start time t to the photographing region 1010-2 at the second frame start time t + Δ t.

Here, the maximum moving distance L between frames_maxMaximum moving speed V of usable car 120_maxExpressed by the product of the frame period Δ t (L)_max＝V_maxX Δ t). The length of the side of the imaging region 1010 in the moving direction (y-axis direction) is L_obsThen, the length of the side in the y-axis direction of the region where the shot regions 1010 in two consecutive frames overlap is represented by "L_obs-L_max"is given.

In fig. 10, the moving side of the repetition area is illustrated by way of exampleLength "L" of side in the direction of (y-axis)_obs-L_max"smaller than the size (length of side in moving direction) L of the brightness mark 150_markIn the case of (1), i.e., "L_mark>L_obs-V_maxWhen the relation of × Δ t "is satisfied, in this case, as shown in fig. 10, in any one of the first frame (time t) and the second frame (time t + Δ t), the luminance mark 150 may not be completely converged in the imaging region 1010, and only an image of a part of the luminance mark 150 is captured, and as a result, the image processing unit 240 fails to read the luminance mark 150 from the captured image.

As described above, in order to completely capture the entire luminance mark 150 in the captured image of at least one of two consecutive frames (time t, time t + Δ t) in the present embodiment, the failure example of fig. 10 is used as a countercheck, and the size L of the luminance mark is required_markIs "L_obs-V_maxX Δ t "or less. By way of specific example, when the frame period (Δ t) is 1mm second and the length (L) of the side in the moving direction (y-axis direction) of the imaging region 1010 is used_obs) When the brightness mark 150 is recognized by the measuring device 110 of 13mm, the maximum moving speed (V) is required_max) The length (L) of the side in the moving direction (y-axis direction) of the brightness mark 150 of the car 120 of 300m per minute_mark) It is required to be at least 8mm or less.

In the present embodiment, for the purpose of redundancy, a plurality of luminance marks 150 representing the same ID pattern 820 may be arranged. In this case, it is not necessary for the size of the whole of the arranged plurality of luminance marks 150 to satisfy the requirement "L" described above_mark≤L_obs-V_maxAt ", but at least one or more luminance marks 150 among the plurality of luminance marks 150 representing the same ID pattern 820 are required to satisfy the above requirement condition. In addition, in consideration of ease of installation, for example, when the brightness mark 150 is attached to the guide rail 140 by a sticker or the like, only the brightness mark 150 printed inside the sticker may satisfy the above requirement conditions, and the size of the sticker may be a size sufficiently larger than the brightness mark 150.

As described above, according to the surveying system 100 of the present embodiment, when the moving body (the elevator car 120) moves, the surveying device 110 mounted on the moving body performs the surveying process shown in fig. 4 on the photographed image of the brightness mark 150 having the characteristics described with reference to fig. 8 to 10, and the like, thereby calculating the absolute position information of the moving body on the moving path at high speed and with high accuracy. That is, according to the measurement system 100 of the present embodiment, the reference position provided in the hoistway is recognized highly accurately from the moving body moving at a high speed, and the absolute position of the moving body in the hoistway can be measured at a high speed and with high accuracy by sequentially adding up the moving distances of the moving body from the reference position. The predetermined control unit (elevator control unit 130) can perform operation control of the mobile body and control of the safety device based on the absolute position information of the mobile body calculated by the measuring device 110.

(1-4) Return operation control of Mobile body when Power is restored

Further, by using the measurement system 100 of the present embodiment, the elevator system 10 can realize the operation control for moving the moving body to the predetermined return position (specifically, the return operation control for returning the elevator car 120 stopped by the power interruption to the nearest floor) when the power is restored after the power interruption such as the power failure occurs.

Fig. 11 is a conceptual diagram for explaining a procedure of return operation control of the elevator car 120. Referring to fig. 11, a process of returning the elevator car 120 stopped at the stop position 1111 by the power supply interruption to the nearest floor 1120 when the power is restored will be described.

First, at the time of installation of the elevator system 10, a floor height table in which the reference position 1112 provided with the brightness mark 150 is associated with the floor position 1113 of each floor is prepared in advance, and the elevator control unit 130 stores the floor height table in advance, for example. The reference position 1112 is a height corresponding to the reference line 810 provided to each of the brightness markers 150, and the floor position 1113 is a height of the measuring device 110 when the car 120 stops at the corresponding floor (for example, the floor 1120).

However, in the elevator system 10, when power supply interruption such as power failure occurs, the operation of the car 120 or the like is stopped, and in this case, the position information of the car 120 measured by the measuring device 110 before power supply interruption may be lost due to power supply interruption. Therefore, when the elevator control unit 130 returns the car 120 to the nearest floor 1120 and then restarts the car control when the power is restored, if the car 120 is returned to the nearest floor 1120 based on the position information measured before the power supply is turned off, a large error may occur.

In order to solve the above problem, in the elevator system 10 of the present embodiment, when returning from power cut, the elevator control section 130 first raises or lowers the car 120 from the position at the time of returning power (the stop position 1111 at which power is cut off), and searches for the brightness mark 150 located at the shortest distance. That is, in fig. 11, as indicated by an arrow 1131, the car 120 is moved from the stop position 1111 to the reference position 1112 where the brightness mark 150 is provided.

Next, the measurement device 110 reads the ID pattern 820 using the combination of the brightness change and the darkness from the captured image of the brightness mark 150 including the reference position 1112, acquires the position information on the reference position 1112 (in other words, the reference line 810 of the brightness mark 150), and transmits the position information to the elevator control unit 130.

The elevator control unit 130 calculates the moving distance of the measuring device 110 to the floor position 1113 when the car 120 is moved to the nearest floor 1120 based on the position information of the reference position 1112 acquired by the measuring device 110 and a floor height table stored in advance. Therefore, the elevator control unit 130 can accurately return the car 120 to the nearest floor 1120 as indicated by an arrow 1132 in fig. 11 by moving the car 120 by the calculated movement distance.

(2) Embodiment mode 2

Fig. 12 is a diagram showing a measuring apparatus 1200 according to embodiment 2 of the present invention, centering on an example of the internal configuration of an imaging unit 1220. The measuring apparatus 1200 according to embodiment 2 is characterized by including the imaging unit 1220 having robustness that can keep the imaging magnification in the imaging unit 230 unchanged with respect to the oscillation of the car 120 in the z-axis direction (see fig. 1), but the other configurations are the same as those of the measuring apparatus 110 according to embodiment 1, and therefore, detailed description thereof is omitted.

In FIG. 12, rays of scattered light from guide rail 140 and brightness marker 150 are shown by dashed lines with arrows (e.g., scattered light 1211-1213). As shown in fig. 12, the imaging unit 1220 images scattered light from the guide rail 140 and the brightness mark 150 onto the imaging unit 230. Specifically, the imaging section 1220 is configured to include an objective lens 1221 (first lens), an aperture 1222, and a condenser lens 1223 (second lens). The objective lens 1221 is disposed opposite to the guide rail 140, and collects the scattered light scattered by the guide rail 140. The aperture 1222 restricts the light amount of the scattered light (scattered light 1211 to 1213) collected by the objective lens 1221. The condenser lens 1223 is disposed between the diaphragm 1222 and the imaging unit 230, condenses the scattered light whose light amount is limited by the diaphragm 1222, and transmits the condensed scattered light to the imaging surface of the imaging unit 230.

In the imaging unit 1220 of the present embodiment, in order to eliminate the influence of the change in magnification when the guide rail 140 as the object to be imaged (the detection target) is moved relative to the car 120 in the z-axis direction, at least the object side (the guide rail 140 side) is telecentric, and in order to suppress the geometric aberration generated in the imaging unit 230, the imaging unit 230 is imaged by two or more lenses. In addition, the imaging unit 1220 may have a telecentric optical arrangement on the image side (the imaging unit 230 side), and in this case, the imaging unit 1220 plays a role of expanding a dimensional tolerance in the z-axis direction (a mounting tolerance in the z-axis direction) when the imaging unit 230 is mounted.

That is, in the measuring apparatus 1200 of the present embodiment, the center of the imaging plane of the imaging section 230, the optical axis of the condenser lens 1223, the center of the diaphragm 1222, and the optical axis of the objective lens 1221 are arranged so as to be located on the same straight line, and the diaphragm 1222 is arranged at the focal position of the imaging section 230 side of the objective lens 1221 and at the focal position of the objective lens 1221 side of the condenser lens 1223.

As shown in fig. 12, in the present embodiment, scattered light from the guide 140 passes through the objective lens 1221, and then an image is formed on the imaging surface of the imaging unit 230 via the condenser lens 1223, and the scattered light rays 1211 to 1213 of the scattered light are principal rays of the imaging optical system. That is, the objective lens 1221, the diaphragm 1222, and the condenser lens 1223 are arranged such that scattered rays 1211 to 1213 pass through the center of the diaphragm 1222, and such that the scattered rays 1211 to 1213 are emitted from the scattering surface of the guide rail 140 always in parallel with the optical axis of the objective lens 1221 and enter the imaging unit 230 always in parallel with the optical axis of the condenser lens 1223.

As described above, according to the measurement device 1200 of the present embodiment, even if the image of the guide rail 140 is shaken in the optical axis direction (z-axis direction), the magnification of the image formed on the imaging surface of the imaging unit 230 can be kept constant, and even if the mounting position of the imaging unit 230 in the z-axis direction is shifted, the magnification of the image formed on the imaging surface of the imaging unit 230 can be kept constant. As a result, the dimensional tolerance when the imaging section 2220 and the imaging section 230 are mounted can be made large, and a more robust optical system can be configured. Further, by using two lenses including the objective lens 2221 and the condenser lens 2223 for the imaging section 2220, it is also possible to expect a reduction in the influence of geometric aberration of the imaging section 2220 that occurs in the imaging section 230.

In the present embodiment, the imaging unit 220 may be configured as a glass lens, with both sides of the objective lens 2221 being spherical, or with one side of the objective lens 2221 being spherical and the other side being flat. The surface through which the light of the condensing lens 2223 can pass may be formed in a shape in which both sides are spherical surfaces, or one side is spherical surface and the other side is flat surface, and may be formed as a glass lens. With such a configuration, in the measuring apparatus 1200 of the present embodiment, the imaging section 2220 can be configured to be less expensive and to have higher durability.

(3) Embodiment 3

Fig. 13 is a diagram illustrating a measuring apparatus 1300 according to embodiment 3 of the present invention, centering on an example of the internal configuration of the imaging unit 1320. The measuring apparatus 1300 of embodiment 3 has the same configuration as the measuring apparatus 1200 of embodiment 2 except that a part of the internal configuration of the imaging section 1320 is different, and detailed description of points common to embodiment 2 is omitted.

In FIG. 13, rays of scattered light from guide rail 140 and brightness marker 150 are shown by dashed lines with arrows (e.g., scattered light 1311-1313). As shown in fig. 13, the imaging unit 1320 images scattered light from the guide rail 140 and the brightness mark 150 onto the imaging unit 230. Specifically, the imaging unit 1320 includes an objective lens 1321 (first lens), a diaphragm 1322, and a condenser lens 1323 (second lens) as in the imaging unit 1220 of embodiment 2 shown in fig. 12, and the imaging unit 1320 includes a mirror 1324 as a configuration unique to the present embodiment.

Here, the configuration and operation of the objective lens 1321, the diaphragm 1322, and the condenser lens 1323 are respectively the same as those of the objective lens 1221, the diaphragm 1222, and the condenser lens 1223 shown in fig. 12, and the object side (the guide rail 140 side) is telecentric and the image side (the imaging unit 230 side) is telecentric. The mirror 1324 is disposed so as to face the guide rail 140, and reflects the scattered light scattered by the guide rail 140 forward toward the objective lens 1321.

Since the surveying instrument 1300 of the present embodiment has the above-described configuration, the same effects as those of the surveying instrument 1200 of embodiment 2 can be obtained. Further, the measuring apparatus 1300 of the present embodiment can realize a more compact structure by using the mirror 1324. That is, as is clear from comparison between fig. 13 and 12, in the measuring apparatus 1300, the imaging unit 1320, the imaging unit 230, and the image processing unit 240 (not shown) can be disposed close to the upper side of the car 120, and therefore, the measuring apparatus 1300 can be mounted on the upper portion of the car 120 without using a special jig.

(4) Embodiment 4

Fig. 14 is a diagram illustrating a measuring apparatus 1400 according to embodiment 4 of the present invention, centering on an example of the internal configuration of an imaging unit 1420. The measurement apparatus 1400 according to embodiment 4 is different from the measurement apparatus 1200 according to embodiment 2 in which the imaging unit 1220 is arranged in the dark-field optical arrangement in that the imaging unit 1420 is arranged in the bright-field optical arrangement, but the measurement apparatus 1400 according to embodiment 4 has basically the same configuration as that of embodiment 2 except that the detailed description of the common points with embodiment 2 is omitted.

In FIG. 14, light rays of scattered light from guide rail 140 and brightness indicia 150 are shown by dashed lines with arrows (e.g., scattered light 1411-1413). As shown in fig. 14, the imaging unit 1420 is disposed in a bright field optical arrangement, and the scattered light of the illumination light from the light transmission unit 210 is imaged on the imaging unit 230. Specifically, the imaging section 1420 includes an objective lens 1421 (first lens), a diaphragm 1422, and a condenser lens 1423 (second lens). The objective lens 1421 is disposed in the guide rail 140 in a direction of regularly reflecting the light emitted from the light transmission unit 210 of the imaging unit 230, and collects the scattered light in the guide rail 140. The configuration and operation of the objective lens 1421, the diaphragm 1422, and the condenser lens 1423 are the same as those of the objective lens 1221, the diaphragm 1222, and the condenser lens 1223 shown in fig. 12, respectively, and the object side (the guide rail 140 side) is telecentric and the image side (the image pickup unit 230 side) is telecentric.

Since the measuring apparatus 1400 of the present embodiment has the above-described configuration, the same effects as those of the measuring apparatus 1200 of embodiment 2 can be obtained. Further, in the measuring apparatus 1400 of the present embodiment, by arranging the imaging sections 1420 in a bright field optical arrangement, the amount of scattered light incident on the imaging section 230 can be increased, and therefore, an effect of improving the processing accuracy of the movement amount calculation processing and the brightness mark recognition processing performed by the image processing section 240 can be obtained.

(5) Embodiment 5

In this embodiment, a description will be given of a measurement system 1500 having a configuration in which the internal configuration (the light transmission unit 210, the imaging unit 220, the imaging unit 230, and the image processing unit 240) of the measurement device 110 in the measurement system 100 according to embodiment 1 and the brightness mark 150 are respectively made redundant.

Fig. 15 is a diagram showing a configuration example of a measurement system 1500 according to embodiment 5 of the present invention. As shown in fig. 15, the measurement system 1500 is configured to include: a measuring device 1510 having two or more measuring portions 1511 (measuring portions 1511-a, 1511-B, respectively); a determination unit 1520 disposed between the measurement device 1510 and the elevator control unit 130; and two or more brightness marks 150 (brightness marks 150-a, 150-B, respectively) affixed to at least two or more positions of the guide rail 140. Although the measurement system 1500 shown in fig. 15 has a duplexed structure and a redundant structure, the redundant structure of the measurement system 1500 is not limited to the duplexed structure in the present embodiment, and may be a triplex or more redundant structure.

In measuring device 1510, measuring sections 1511-A and 1511-B have the same internal configuration as measuring device 110, respectively. Specifically, the measurement portion 1511-A includes a light transmission portion 210-A, an imaging portion 220-A, an imaging portion 230-A, and an image processing portion 240-A, and the measurement portion 1511-B includes a light transmission portion 210-B, an imaging portion 220-B, an imaging portion 230-B, and an image processing portion 240-B.

In the measuring apparatus 1510 configured as described above, the measuring units 1511-a and 1511-B each independently perform the same measurement processing as the measuring apparatus 110 on the brightness mark 150 (the brightness mark 150-a in the case of the measuring unit 1511-a and the brightness mark 150-B in the case of the measuring unit 1511-B) as the imaging target of each measuring unit 1511 out of the two or more brightness marks 150 attached to at least two or more upper positions of the guide rail 140. That is, the light transmitting unit 210 irradiates the luminance mark 150 as the imaging target with the emitted light, the imaging unit 220 images the scattered light of the luminance mark 150 on the imaging surface of the imaging unit 230, the imaging unit 230 converts the optical signal coupled to the imaging surface into an electric signal corresponding to the luminance of the pixel, and the image processing unit 240 calculates information on the movement of the car 120 (car movement related information) and information on the reference position (reference position related information) included in the luminance mark 150 as the imaging target based on the captured image generated by performing image processing on the electric signal. However, the measurement units 1511-a and 1511-B transmit the calculation results of the image processing units 240 to the determination unit 1520, instead of the elevator control unit 130, as a point different from the measurement device 110.

Then, the determination unit 1520 performs the comparison processing described in the following paragraph on the signal information (the car movement related information and the reference position related information) transmitted from each of the plurality of measurement units 1511 (specifically, the image processing unit 240) of the measurement device 1510, thereby determining the abnormality related to the plurality of measurement units 1511 and the brightness mark 150.

As the comparison process, the determination unit 1520 determines whether or not at least two pieces of signal information received from the measurement device 1510 are the same. When it is determined by the determination that the two or more signal information are the same, the determination unit 1520 can determine that the measurement device 1510 and the brightness flag 150 normally operate. On the other hand, when it is determined by this determination that any signal information is not the same as the other signal information, the determination unit 1520 can determine that there is an abnormality in at least either the measurement device 1510 or the brightness marker 150.

In the present embodiment, "the signal information is the same" may mean that the contents of the signal information to be compared completely match, but may mean that the contents of the signal information to be compared almost match (substantially match). The case of complete matching can be exemplified by the case where the position of the car 120-a transmitted from the image processing unit 240-a and the position of the car 120-B transmitted from the image processing unit 240-B have the same value. In addition, as a case of approximate matching, for example, a difference between the position of the car 120-a transmitted from the image processing portion 240-a and the position of the car 120-B transmitted from the image processing portion 240-B is within a predetermined range (for example, a range of allowable error).

In the case where the measuring device 1510 has three or more measuring units 1511, in the comparison process of the determination unit 1520, for example, it is determined whether all the paired signal information are the same, and if it is determined that all the paired signal information are the same, it is determined that the operation is normally performed, and if it is determined that one or more paired signal information are not the same, it is determined that at least one of the measuring device 1510 and the brightness mark 150 is abnormal.

As a result of the comparison processing described above, when it is determined that the measurement device 1510 and the brightness mark 150 normally operate, the determination unit 1520 transmits the signal information (which may be one of the same signal information) received from the measurement unit 1511 and the signal information (information indicating the normal determination) indicating the determination result that the measurement unit 1511 normally operates to the elevator control unit 130.

On the other hand, when it is determined that there is an abnormality in at least one of the measuring device 1510 and the brightness mark 150 as a result of the comparison processing, the determination unit 1520 transmits signal information (information indicating abnormality determination) indicating the determination result that the measuring unit 1511 performs an abnormal operation to the elevator control unit 130. In addition to the above-described determination of the presence or absence of an abnormality, the determination unit 1520 may identify the type of an abnormality by analyzing information on the captured image acquired by each measurement unit 1511, information on the movement of the car 120 (car movement-related information), information on the reference position of the brightness marker 150 (reference position-related information), and the like. In the analysis method, a detailed description is omitted since a known analysis method can be appropriately used, but by identifying the kind of abnormality, specifically, for example, damage of the components of the measuring device 1510, abnormal vibration due to looseness or damage of the mounting jig, deviation of the mounting position, inclination, corrosion of the guide rail 140, contamination, adhesion of foreign matter, defect of the brightness mark 150, and the like can be detected.

As described above, according to the measurement system 1500 of the present embodiment, by adopting a redundant configuration, even when an abnormality such as a failure, dirt, or a defect occurs in the measurement device 1510 (measurement portion 1511) or the brightness marker 150, it is possible to safely detect the occurrence of the abnormality without causing an obstacle to the operation of the elevator car 120. Further, when the occurrence of an abnormality is detected, the kind of the abnormality can be identified by analyzing the information acquired from the measurement device 1510, and thus an appropriate recovery job can be quickly performed.

(6) Other embodiments

In each of embodiments 1 to 5, the case where the present invention is applied to the measuring device of the elevator car 120 in the elevator system has been described, but the present invention is not limited thereto, and can be widely applied to various other systems, devices, methods, and programs.

For example, the measuring device 110 according to embodiment 1 (or the measuring device according to another embodiment) can be applied not only to the operation of an elevator but also to an application for detecting a position or a speed with high accuracy in a vehicle traveling at high speed such as an automobile or a train. For example, in an autonomous vehicle, the measuring device 110 can be used for the purpose of position monitoring and speed monitoring on a highway, or for the purpose of positioning with high accuracy in a parking lot, a gas station, a charging station, or the like.

Fig. 16 is a diagram showing a configuration example of a vehicle positioning system 1600 in which the measurement device 110 is applied to a vehicle. Fig. 16(a) shows an example of pasting the brightness mark 150 on the road surface 1620, and fig. 16(B) shows an example of pasting the brightness mark 150 on the wall 1630 of the expressway.

As shown in fig. 16, in the vehicle positioning system 1600, the measuring device 110 is disposed on a side portion or an upper portion of a vehicle 1610 (e.g., an automobile or a train), and the vehicle 1610 travels in a road surface 1620. The measurement device 110 outputs signal information useful for performing operation control of the vehicle 1610 to a vehicle control unit (not shown). The vehicle control unit is provided to safely operate/stop the vehicle 1610, which is automatically driven, for example.

The luminance mark 150 indicating the reference position in the road is attached to a predetermined stationary structure (a road surface 1620 in fig. 16 a and a wall surface 1630 in fig. 16B) existing in the vicinity of the vehicle 1610. Although only one brightness mark 150 is shown in fig. 16, in practice, a plurality of brightness marks 150 may be arranged on the stationary structure along the moving direction of the moving body, each brightness mark 150 including a corresponding reference line 810 and ID pattern 820. Specifically, the brightness mark 150 is attached to a wall 1630 in front of a traffic light that needs to stop the vehicle 1610 safely, or to a road surface 1620 that needs to position and stop the vehicle 1610 with high accuracy, such as a parking lot and a gas station. For example, when the application object of the measuring device 110 is a train, the brightness mark 150 may be disposed along a track on which the train travels.

By applying the measuring device 110 to the autonomous vehicle (vehicle 1610) as described above, the vehicle positioning system 1600 in fig. 16 a can measure the position of the vehicle 1610 with high accuracy using the brightness mark 150 disposed on the road surface 1620, and thus can contribute to control to stop the vehicle 1610 at a predetermined destination (parking lot, gas station, charging station, or the like) with high accuracy. Similarly, the vehicle positioning system 1600 in fig. 16B can measure the position of the vehicle 1610 with high accuracy using the brightness mark 150 disposed on the wall surface 1630, and thus can contribute to control for safely stopping the vehicle 1610 at a predetermined point (such as in front of a traffic light).

For example, the measuring device 110 according to embodiment 1 (which may be the measuring device according to another embodiment) can be applied to the operation control of the crane.

Fig. 17 is a diagram showing a configuration example in which the measuring device 110 is applied to a crane positioning system 1700 of a crane. In the crane positioning system 1700 shown in fig. 17, the measuring device 110 is disposed on the side or upper portion of the crane 1710 that runs in the 1-axis direction along the rail 1720. In fig. 17, the rail 1720 corresponds to a stationary structure on which the brightness marker 150 is disposed, and the brightness marker 150 is disposed along the moving direction of the crane 1710.

In the crane positioning system 1700, the measurement device 110 photographs a wall surface of the rail 1720, measures the movement amount and speed of the crane 1710 (information on the movement of the crane 1710), and acquires information on the reference position of the brightness mark 150 by reading the brightness mark 150 pasted on the rail 1720. A crane control unit (not shown) of the crane 1710 monitors the operation of the crane 1710 based on the above-described information (that is, information on the movement of the crane 1710 and information on the reference position of the brightness marker 150) useful for the operation control of the crane 1710, and detects a position abnormality and a speed abnormality.

By applying the measuring device 110 to the crane 1710 as described above, the crane positioning system 1700 can improve the safety of the operation control of the crane 1710 in the operation control of the crane 1710.

The above embodiments are for easy understanding of the present invention, and do not limit the scope of the present invention. Further, a part of the configuration of each embodiment may be added, deleted, replaced, or the like with another configuration. Further, each of the above-described structures, functions, processing units, and the like may be partially or entirely realized by hardware obtained by designing an integrated circuit, for example. The above-described structures, functions, and the like may be interpreted as programs that are respectively implemented by the processor, and the programs may be implemented in the form of software by executing the programs. Information such as programs, tables, and files for realizing the respective functions can be stored in a recording device such as a memory, a hard disk, an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.

The drawings show control lines and information lines necessary for the explanation, but the drawings do not necessarily show all control lines and information lines necessary for a product. Virtually all structures can be considered interconnected.

Description of the reference symbols

10 Elevator system

100 measurement system

110 measuring device

120 Elevator lift-cabin (Car)

130 elevator control part

140 guide rail

150 (151-153) brightness mark

210 optical transmission part

220 image forming section

230 imaging unit

240 image processing unit

310 control unit

320 movement amount calculating unit

330 brightness mark identification part

340 communication part

510 scattered brightness distribution

520 shooting image

610 gating signal

710. 910 distribution of scattered light intensity

720. 920 photographing an image

810 reference line

820 ID pattern

1010 shooting area

1111 stop position

1112 reference position

1113 floor position

1120 nearest floor

1200. 1300, 1400 measuring device

1211 to 1213, 1311 to 1313, 1411 to 1413 scattering light

1220. 1320, 1420 imaging part

1221. 1321, 1421 objective lens

1222. 1322, 1422 diaphragm

1223. 1323, 1423 condensing lens

1324 mirror

1500 measurement system

1510 measuring device

1511 measuring part

1520 determination unit

1600 vehicle position locating system

1610 vehicle

1620 road surface

1630 the wall surface

1700 crane positioning system

1710 crane

Rail 1720.

Claims

1. A measuring device, arranged on a moving body moving on a moving path and measuring the position of the moving body, is characterized in that, comprising:

A light transmitting unit that transmits, in response to a strobe signal generated at a predetermined cycle, a transmission for a stationary structure arranged in a first direction parallel to the moving direction of the moving body on the moving path irradiated light;

an imaging unit that images the scattered light from the stationary structure generated by the light on the imaging surface;

an imaging unit that acquires an optical signal of the scattered light imaged on the imaging surface within an exposure time specified by the gate signal, and converts it into an electrical signal; and

an image processing unit that generates the gate signal at the predetermined cycle, performs image processing on the electrical signal converted by the imaging unit to generate a captured image, and generates a captured image based on the captured image, to calculate information about the absolute position of the moving body,

The image processing unit includes:

Mark recognition processing in which, when an image of a marker provided on the stationary structure is included in the captured image, a second direction perpendicular to the first direction in the captured image is used. the light and dark luminance changes to determine a reference line representing a reference for the absolute position of the marker; and

Movement amount calculation processing in which the movement amount of the moving body from the reference line determined by the marker recognition processing is calculated.

2. The measuring device according to claim 1, characterized in that,

The exposure time is set to a value smaller than the time calculated from the ratio of the spatial resolution of the image formed on the photographing surface to the maximum moving speed of the moving body.

3. The measuring device of claim 1, wherein

In the movement amount calculation process, the image processing unit generates the imaging of each frame from the electrical signal converted by the imaging unit at a frame cycle corresponding to a generation cycle of the gate signal. image,

Among the generated captured images of the plurality of frames, the first measurement target image included in the captured image of the previous first frame and the captured image included in the second frame after the first frame are calculated. The deviation on the images generated between the second measurement object images, thereby calculating the moving distance of the moving body from the first frame to the second frame,

The moving speed of the moving body is calculated from the calculated ratio of the moving distance to the time difference between the first frame and the second frame.

4. The measuring device of claim 1, wherein

The imaging part includes a first lens, and the first lens condenses the scattered light from the stationary structure;

an aperture, which limits the amount of scattered light obtained by condensing the first lens; and

a second lens arranged between the aperture and the imaging surface and condensing the scattered light whose light quantity is limited by the aperture,

A telecentric optical arrangement is performed on at least the first lens arranged on the stationary structure side.

5. A measurement system for measuring the position of a moving body moving on a moving path, comprising:

a measuring device provided on the moving body; and

Marks are provided on the stationary structures along the moving path along a first direction parallel to the moving direction of the moving body, and at least one marker is provided at predetermined intervals along the first direction, respectively,

The measuring device includes:

a light transmitting unit that transmits, in response to a strobe signal generated at a predetermined cycle, a signal for irradiating a stationary structure arranged in a first direction parallel to the moving direction of the moving body on the moving path Light;

an image processing unit that generates the gate signal at the predetermined cycle, performs image processing on the electrical signal converted by the imaging unit, generates a captured image, and calculates based on the captured image information about the absolute position of the moving body,

The image processing unit includes:

Mark recognition processing, in the mark recognition processing, when the image of any one of the markers is included in the captured image, the change of brightness and darkness in the second direction perpendicular to the first direction in the captured image is used to identify determining a reference line representing a reference for the absolute position of the marker; and

6. The measurement system of claim 5, wherein

The moving body is an elevator car moving in a hoistway in an elevator system,

On the stationary structure arranged in the hoistway, at least one of the marks is provided between each floor along the first direction.

7. The measurement system of claim 5, wherein

The length of the side in the first direction of the mark is subtracted from the length of the side in the first direction of the imaging area of the imaging unit by multiplying the maximum moving speed of the moving body by the equivalent of The length obtained after the size obtained by the frame time of the generation cycle of the strobe signal is less than or equal to the length obtained.

8. The measurement system of claim 5, wherein

The length of the side of the mark in the first direction is 8 mm or less.

9. The measurement system of claim 5, wherein

The length of the side of the mark in the second direction perpendicular to the first direction is defined as the length of the side that can be located in the second direction by subtracting the length of the side of the imaging area of the imaging unit in the second direction. The length obtained after the displacement amount of the maximum rocking in the second direction generated on the moving body is less than or equal to the length.

10. The measurement system of claim 5, wherein

The marks disposed on the moving path at different positions in the first direction respectively have:

the reference line as a reference for the absolute position of the marker; and

An ID pattern representing the absolute position information of the reference line using a combination of light and dark brightness changes that are different for each of the marks,

In the marker recognition process, the image processing unit recognizes the ID pattern to which the marker is given with respect to an image of the marker included in the captured image, and performs decoding processing from The identified ID pattern acquires the absolute position information represented by the ID pattern.

11. The measurement system of claim 10, wherein

In the marking, the minimum period of light and dark brightness changes in the ID pattern is greater than the spatial resolution of the image imaged on the shooting surface, and the number of combinations of light and dark brightness changes in the ID pattern is set at more than the total number of the marks at different positions in the first direction on the moving path.

12. The measurement system of claim 10, wherein

The ID pattern given to the mark is composed of a combination of light and dark brightness changes arranged in a one-dimensional array in the first direction,

In the marker recognition processing, the image processing unit performs decoding processing of the ID pattern using the change in brightness and darkness in the first direction in the marker as an index.

13. The measurement system of claim 10, wherein

The ID pattern given to the mark is composed of a combination of light and dark brightness changes arranged in a two-dimensional array in the first direction and a second direction perpendicular to the first direction,

In the marker recognition processing, the image processing unit performs decoding processing of the ID pattern using the change in brightness and darkness in the marker in the first direction and the second direction as an index. .

14. The measurement system of claim 10, wherein

The image processing unit learns the ID pattern assigned to the marker before performing the decoding process, assigns absolute position information of the marker corresponding to the feature point of each ID pattern obtained by learning, and stores the absolute position information. location information,

In the marker recognition process, the feature point recognition process is performed on the captured image, and the ID pattern decoding process is performed using the feature point recognized in the recognition process as an index.

15. A moving body operation method, which is a moving body operation method by an elevator system for returning an elevator car to a nearby floor, characterized in that:

The elevator system includes:

a mark, the mark is arranged on a stationary structure in a hoistway along a first direction parallel to the moving direction of the elevator car, and at least one mark is provided between each floor along the first direction;

a measuring device, which is arranged on the elevator car, photographs the stationary structure, and calculates the position information of the marker when the image of the marker is included in the photographed image;

an elevator control that controls the motion of the elevator car; and

floor height information indicating, for the mark corresponding to each of the floors, the position information of the mark and the floor,

The moving body operating method includes:

a first step of moving the elevator car to the mark in the vicinity by the elevator control unit;

a second step of calculating, by the measuring device, position information of the marker based on a captured image of the marker at the destination of the first step;

a third step of calculating, by the elevator control unit, a moving distance from the marker to the floor based on the position information of the marker and the floor height information calculated in the second step; and

A fourth step in which the elevator car is moved by the elevator control unit by the moving distance calculated in the third step.