JP4505408B2 - Electromagnetic / ultrasonic call / answer (EURA) system for elevator positioning - Google Patents

Description

  The present invention relates to an apparatus and method for determining the position of a movable platform using ultrasound and RF signals. More particularly, the present invention relates to a method for locating transceivers and transponder modules so that the position of an operating elevator car can be measured.

  The Positioning Reference System PRS is a component of an elevator control system that provides fast and accurate position measurement of an elevator car within an elevator hoistway. Many existing PRS are based on encoders attached to elevator motors, governors, or independent sheaves. These PRSs suffer from differences between encoder readings and actual positions caused by slips, rope stretch, mechanical wear in the subsystem, and / or building sway. In order to minimize this difference, frequent corrections need to be made based on some fixed known reference point that indicates the actual location of the hall and the leveling zone. A vane system consisting of a vane reader and vanes provides these reference points and their detection means. Considering the simple function of this vane system, maintenance personnel will need $ 10 for material costs, 0.5 hours for installation and about 0.1 hours for adjustment to install vanes in the elevator hoistway on each floor Therefore, the vane system is extremely low in cost. Overall, the most important problem with existing PRS is the high performance to cost ratio.

  In response to the shortcomings of the existing PRS, a passive ultrasonic RF-ID system (Passive Ultrasonic RF-ID Systems) called PURIS has been developed. However, the PURIS system poses additional challenges. For example, wireless power supply via ultrasound may not be sufficient to activate the transponder. In addition, aerodynamic interference can significantly degrade positioning performance.

  Each of these problems is technically solved by using RF to power the transponders, as in RFID systems, and using four transponders (PURIs) instead of two for each door frame. Can do.

  These two solutions are good enough, but the first solution requires custom manufacturing of the solid state RFID system, and the second is more than necessary because the resulting system material costs are almost doubled. Can be expensive. Wire feeding can easily solve the first problem. However, the second problem in the PURIS framework still cannot be solved.

  Accordingly, there is a need for a high precision positioning means that is low in material, installation and maintenance costs.

  It is an object of the present invention to provide an apparatus and method for determining the position of a movable platform using ultrasound and RF signals.

  A positioning system according to the present invention has a plurality of transponder modules each having a unique ID and receiving an electromagnetic signal including a code and transmitting an ultrasonic signal when the code is equal to the unique ID, at least three A transceiver module having at least one set of ultrasonic signal receivers and transmitting at least one encoded electromagnetic signal and receiving ultrasonic signals; transmitting at least three encoded electromagnetic signals; and Means for measuring the duration between reception of the ultrasound signal by the ultrasound receiver and means for determining the location of the transceiver module from this duration.

  An apparatus for measuring the position of a movable platform according to the present invention includes an RF receiver provided to receive a coded RF signal, an ultrasonic transmitter provided to transmit an ultrasonic signal, and an arithmetic unit. A plurality of transponder modules, and an RF transmitter provided to emit a coded RF signal, a plurality of ultrasonic receivers provided to receive an ultrasonic signal, a coded RF signal A movable platform including a timekeeping mechanism for measuring a plurality of durations between transmission of a signal and reception of an ultrasound signal by a plurality of ultrasound receivers, and a computing mechanism for processing these plurality of durations It has at least one transceiver module attached.

  A method for measuring the position of a movable platform according to the present invention comprises the steps of placing a plurality of transponder modules for receiving an encoded RF signal and transmitting an ultrasonic signal in a fixed position, one code Locating at least one transceiver module for transmitting a coded RF signal and receiving the ultrasound signal using a plurality of ultrasound receivers, sending a coded RF signal, coded Receiving an RF signal and transmitting an ultrasonic signal in response thereto, receiving an ultrasonic signal using a plurality of ultrasonic receivers, transmitting a coded RF signal and receiving a plurality of ultrasonic signals Measuring a plurality of durations between reception of the ultrasonic signal by the machine and the transceivers from these durations Comprising the step of identifying the location of the module.

  Yet another method for measuring the position of a movable platform according to the present invention includes an RF transmitter provided to transmit a coded RF signal, a plurality of ultrasonic receivers provided to receive an ultrasonic signal. A timekeeping mechanism for measuring a plurality of durations between the transmission of a coded RF signal and the reception of an ultrasound signal, and an operation for processing the plurality of durations to calculate a position Attaching at least one transceiver module having a mechanism to a movable platform, an RF receiver provided to receive a coded RF signal, an ultrasonic transmitter provided to emit an ultrasonic signal, and an operation Placing a plurality of transponder modules each having a unit in a fixed position; and a plurality of transponders Transmitting a coded RF signal received by one of the transponder modules from the transceiver module and activating a timing mechanism; receiving the RF signal encoded by one of the plurality of transponder modules; Responsively transmitting an ultrasonic signal, receiving the transmitted ultrasonic signal using a plurality of ultrasonic receivers, transmitting an encoded RF signal and a plurality of ultrasonic receivers Measuring at least three durations between reception of ultrasonic signals using a timing mechanism and calculating the position of the movable platform using a fixed position and at least three measured durations Including the steps of:

  The present invention discloses an electromagnetic / ultrasonic roll-calling / answering EURA system.

  The EURA system consists of a plurality of transponder modules, preferably one for each landing, and a transceiver module attached to the elevator cab. The electromagnetic waves used as an example in the present disclosure are radio frequency (RF) waves. However, other electromagnetic waves such as microwaves or light can also be used for the implementation of this concept. Although the elevator is described here, the present invention is not limited thereto. Rather, the present invention is directed to an EURA system for use with any mobile platform.

  Referring to FIG. 1, the transponder module of the present invention is illustrated. The transponder module 10 includes an RF receiver 11, a narrow beam angle ultrasonic transmitter 13, and an arithmetic unit 15. The transponder module 10 is pre-installed at the same location on each door frame seal along the elevator hoistway as will be described below. The feeder 17 for the transponder is also properly installed in the door frame in advance. As used herein, the expression “install in advance” means installation performed outside the elevator hoistway. The ultrasonic transmitters 13 of the transponder module 10 are mounted either all upwards or all downwards. The ultrasonic sensors in the transceiver module described below are in the opposite direction to the ultrasonic transmitter 13, i.e. all downward or all upward. Here, it is assumed that the transponder module 10 faces upward and the transceiver module faces downward.

  The RF receiver 11 receives a predetermined frequency signal from the transceiver module, demodulates it, extracts a code, and transmits the code to the arithmetic unit 15. This code is compared with a unique ID number stored in the arithmetic unit. The unique ID can be determined in advance, can be learned by the transponder in a special learning mode, or can be set on site by the maintenance staff. If the code is the same as the ID number, the arithmetic unit triggers the ultrasonic transmitter 13 to transmit an ultrasonic signal. Here, it is assumed that there is a power supply for each transponder module.

  The distance between any two adjacent transponder modules 10 is limited to Xm. This means that one or more transponder modules 10 must be installed between two adjacent transponder modules 10 separated by more than Xm. Preferably, the distance between floors is about 3.5 m, with the exception of the first floor with a high ceiling or the express zone. Therefore, X can be set to 3.5. However, X can be any distance sufficient to provide operation of the EURA system. This parameter is used to set another parameter for the transceiver module 20 described below.

Referring to FIG. 2, a transceiver module 20 of the present invention is illustrated. The transceiver module 20 consists of two RF transmitter circuits 21, two composite ultrasonic receivers 23, 23 ′, and two separate arithmetic units 25. The following drawings show the components. In the preferred embodiment shown, circuit overlap is due to regulatory redundancy, and one set of circuits is used for normal positioning and normal terminal device (NTSD) functions. The other set is used for emergency terminal stopping device ETSD / ETSLD function. Each composite ultrasonic receiver 23, 23 'has two sets of three ultrasonic sensors 28, ie 27, 27', which are shared with the other receiver 23, 23 '. . Of course, there are other sensor redundancy designs that use fewer sensors due to design complexity and tradeoffs. The distance between two adjacent sensors 28 in the set is preferably about 10 cm, but can be smaller. The distance Y between the two sets is given by:
Y> XZ
Where Z is a system parameter that represents the maximum distance between the transmitter and receiver pair. Preferably Z is 3 m, 2 m or 1 m. A smaller Z means a smaller measurement delay. The parameter Y satisfying the above equation ensures that there is a transponder module 10 located below Z from one of the two sets of ultrasonic sensors 27, 27 'in the transceiver module 20 for any moment. To do.

  The transceiver module 20 can be installed in advance or can be installed in an elevator hoistway. Preferably, the transceiver module 20 is installed on the side of the cab 37.

  Now consider only one of the circuit sets 27, 27 '. The RF transmitter 21 calls the transponder module 20 every predetermined time, for example, every 10 ms. This time interval can be any length sufficient to facilitate operation of the EURA system. The moment of calling is imprinted by the arithmetic units 25, 25 '. Details of determining which transponder module 10 is called will be described later. Briefly, the transponder module 10 that is closest to the transceiver module 20 is called by the transceiver module 20. This logic is valid because the PRS knows the approximate location of the cab 37 and the transponder module 10 except in the case of a power failure.

  After calling the transponder module 10, the transceiver module 20 waits until an ultrasonic signal is received at each ultrasonic sensor. Each reception at each sensor 28 is stamped by the arithmetic unit 25.

  The arithmetic unit 25 uses the time information of the call as well as the first to third receptions for the calculation of the cab position. This position calculation is possible because there are three unknown variables: vertical and horizontal cab position, and local acoustic velocity, but three independent equations are obtained from the three ultrasonic sensors 28. . It should be noted here that there is a deterministic time bias in flight time caused by some delay in communication and computation. In fact, one important constraint in the implementation of this system is the setting of the time range, ie the time range during which communication success is guaranteed.

  FIG. 3 shows the configuration of the resulting EURA system in detail. The main difference between the PURIS and EURA systems is that the transceiver 20 knows the ID number of each transponder 10 and calls only one transponder 10 by its ID number, rather than calling multiple transponders 10 simultaneously. Note again.

In normal operation, the EURA system functions as follows.
1. The transceiver module 20 knows the cab position 10 ms ago and the absolute position and ID of each transponder module.
2. The transceiver module 20 invokes the transponder module 10 closest to the center point between the two sets 27, 27 ′ of the ultrasonic sensors 28 via the coded RF signal 39. The moment of call is imprinted.
3. Each transponder module 10 is continuously listening to the transceiver module 20, decodes any received RF signal 39, and compares its code with its own ID. If the code is the same as its own ID, the ultrasonic transmitter 13 is triggered to transmit an ultrasonic signal.
4). The transceiver module detects the reception of the ultrasonic signal 35 at each ultrasonic sensor 28 and stamps it.
5). The transceiver uses at least three receive stamps to calculate the cab position. This calculation can be as simple as solving three simultaneous equations or more complex. For example, various echoes may be present because the ultrasound signal reflects from the cab and / or elevator hoistway walls. Adaptive echo cancellation can be used to reduce this type of interference.
Note: For multiple elevator hoistways, each elevator hoistway has a different set of RF and ultrasonic signal frequencies to minimize any kind of signal interference.

  For NTSD and ETSD operation, a transponder module is installed every X / 2m. By doing so, the original measurement delay can be reduced to half. In the NTSD and ETSD domains, the two sets of circuits 27, 27 'perform a normal positioning process with a start time difference of 5ms. That is, after one set 27 calls the transponder module at t = 0, the other set 27 'starts its operation at t = 5ms. One set is for NTSD and the other is for ETSD / ETSLD. By measuring the frequency shift caused by the Doppler effect, or by differentiating the position measurement, the transceiver module calculates the moving speed of the cab.

  For positioning within the express zone, a transponder module 10 is installed at both ends of each express zone for early detection of both ends of the express zone. The transponder module 10 attached to the bottom end includes a long range ultrasonic transmitter. Here it is assumed that the range covers the entire express zone. If that is not possible, install the transponder module 10 in the express zone.

  After the cab 37 enters the express zone and passes the transponder module located at the end of the zone, the transceiver module 20 relies on the long range transponder module 10 for positioning. The transceiver module 20 requires a longer wait until receiving an ultrasonic response. When one is received, the transponder module 10 is subsequently called again.

  To restore position after a power failure, the transceiver module 20 calls the transponder module 10 in order from the top of the elevator hoistway. Since all the ultrasonic transmitters 13 in the transponder module 10 are assumed to be upward, the transceiver module 20 is located below the upper set 27 of ultrasonic sensors 28 in the transceiver module 20. A valid ultrasonic wave 21 cannot be detected until the first transponder module 10 is called. Additional fault tolerance for undesired responses is possible by time gating of acceptable responses.

  When the first transponder module 10 located below the upper set 27 of ultrasonic sensors in the transceiver module 20 is called, the transceiver module 20 can recover the current position information of the cab 37.

  As a result, the present invention provides highly accurate position measurement anywhere in the elevator hoistway, has a high position update rate, lower installation / adjustment costs for minimal elevator hoistway installation / adjustment, simple structure and There is no maintenance cost due to no mechanical wear, low management costs due to global applicability, and no need for corrective travel.

  Although this disclosure is shown for vertical elevator transport, it is equally applicable to the more general, horizontal and vertical transport.

  In accordance with the present invention, an apparatus including ultrasonic and RF signals for determining the position of a movable platform and a method for using the same are provided, and the objectives, means, and advantages set forth above are fully met. It is clear. Although the invention has been described with reference to specific embodiments thereof, other changes, modifications, and variations will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, it is intended to include those changes, modifications and variations as falling within the broad scope of the appended claims.

FIG. 2 is a schematic diagram of a transponder module of the present invention. FIG. 3 is a schematic diagram of a transceiver module of the present invention. 1 is a schematic diagram of a preferred embodiment of the EURA system of the present invention.

Claims (10)

A plurality of transponders provided along a moving path of the elevator car, each having a unique ID, receiving an electromagnetic signal including a code, and transmitting an ultrasonic signal when the code is equal to the unique ID; Module,
A transceiver module attached to the elevator car, having at least one set including at least three ultrasonic signal receivers, transmitting at least one encoded electromagnetic signal and receiving the ultrasonic signal When,
Means for measuring a duration between transmission of the encoded electromagnetic signal and reception of the ultrasonic signal by the at least three ultrasonic receivers;
The position of the transceiver module, have a, and means for identifying from the time duration,
The transponder module is a positioning system in which an end region of a moving path of the elevator car is arranged at a shorter interval than a central region . Before SL electromagnetic signal is an RF signal, the positioning system according to claim 1. The positioning system of claim 1, comprising two sets comprising at least three ultrasonic signal receivers. A device for measuring the position of an elevator car ,
An RF receiver arranged to receive the encoded RF signal;
An ultrasonic transmitter provided to transmit an ultrasonic signal;
A plurality of transponder modules provided along a movement path of the elevator car ,
An RF transmitter provided to emit a coded RF signal;
A plurality of ultrasonic receivers provided to receive ultrasonic signals;
A timekeeping mechanism for measuring a plurality of durations between transmission of the encoded RF signal and reception of the ultrasound signal by the plurality of ultrasound receivers;
Wherein the plurality of processing the duration anda calculation device for calculating the position, and have a at least one transceiver module attached to said elevator car,
The transponder modules are arranged in the end region of the elevator car travel path at shorter intervals than the central region . The apparatus of claim 4 , wherein the elevator car is provided for movement along a central axis.   The apparatus of claim 4, wherein at least two of the transponder modules are mounted on a plurality of door frames. A plurality of transponder modules that receive coded RF signals and emit ultrasonic signals are placed at fixed positions along the travel path of the elevator car, and in the end region of the travel path of the elevator car Placing at shorter intervals than the central region ;
Placing at least one transceiver module in the elevator car that emits a coded RF signal and receives the ultrasound signal using a plurality of ultrasound receivers;
Transmitting the encoded RF signal;
Receiving the encoded RF signal and transmitting an ultrasonic signal in response;
Receiving the ultrasonic signals using the plurality of ultrasonic receivers;
Measuring a plurality of durations between transmission of the encoded RF signal and reception of the ultrasound signal by the plurality of ultrasound receivers;
Determining the position of the transceiver module from the duration. A method for measuring the position of an elevator car ,
Attaching at least one transceiver module to the elevator car , the transceiver module comprising:
An RF transmitter provided to emit a coded RF signal;
A plurality of ultrasonic receivers provided to receive ultrasonic signals;
A timekeeping mechanism that measures a plurality of durations between transmission of the encoded RF signal and reception of the ultrasound signal;
An arithmetic mechanism for processing the plurality of durations,
A plurality of transponder modules are arranged at fixed positions along the movement path of the elevator car , respectively, and are arranged at intervals shorter than the central area in the end area of the movement path of the elevator car , The transponder module
An RF receiver arranged to receive the encoded RF signal;
An ultrasonic transmitter provided to transmit an ultrasonic signal;
Each having an arithmetic unit,
Transmitting the encoded RF signal received by one of the plurality of transponder modules from the transceiver module and activating a timing mechanism;
Receiving the encoded RF signal by one of the plurality of transponder modules and transmitting an ultrasonic signal in response;
Receiving the transmitted ultrasonic signals using the plurality of ultrasonic receivers;
Measuring at least three durations between transmission of the encoded RF signal and reception of the ultrasound signal by the plurality of ultrasound receivers using the timekeeping mechanism;
Calculating the position of the elevator car using the fixed position and the at least three measured durations. 9. The method of claim 8 , wherein disposing the plurality of transponder modules includes disposing at least one of the transponder modules for each floor of a building. 9. The method of claim 8 , wherein disposing the plurality of transponder modules includes disposing at least two of the transponder modules in a line parallel to a central axis along which the elevator car moves.

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