KR20200122542A - Apparatus and method for scan miniature of lidar sensor - Google Patents

Abstract

The present invention relates to a lidar sensor scan precision apparatus and method.
A lidar sensor scanning precision apparatus according to an embodiment of the present invention includes a scanner reflector having a magnet and transmitting a laser signal, a motor connected to the scanner reflector and rotating by a control signal to rotate the scanner reflector, A first Hall sensor and a second Hall sensor respectively mounted at a predetermined position of a motor housing equipped with the motor and outputting a first voltage signal and a second voltage signal when the magnet is sensed by rotation of the scanner reflector, the Outputs the control signal for controlling the rotational operation of the motor, and counts the number of laser transmission signals from the time when the first voltage signal is received from the first Hall sensor to the time when the second voltage signal is received from the second Hall sensor And a control unit for adjusting the laser transmission interval based on the counted number of laser transmission signals.

Description

LIDAR sensor scan precision device and method {APPARATUS AND METHOD FOR SCAN MINIATURE OF LIDAR SENSOR}

The present invention relates to an apparatus and method for precise scanning of a lidar sensor, and based on the number of laser transmission signals generated during an area not scanned by a lidar sensor, the lidar sensor adjusts the laser transmission interval of an area that actually needs to be scanned. It relates to a scan refinement apparatus and method.

In general, a light detection and ranging (LIDAR) sensor is a sensor that measures a distance and detects an object using light, and a lidar has a principle similar to that of a radar. However, the radar emits electromagnetic waves to the outside and checks the distance and direction with the re-received electromagnetic waves, but the difference is that the radar emits a pulsed laser. In other words, since a laser with a short wavelength is used, precision and resolution are high, and three-dimensional grasp is possible depending on objects.

For example, a lidar sensor is mounted on a bumper of a vehicle to sense the front/rear of the vehicle to detect objects or structures. For reference, FIG. 1 is an exemplary view showing a field of view (FOV) of a lidar sensor mounted on a front/rear bumper of a vehicle.

Meanwhile, the lidar sensor is mainly mounted on the front bumper and must be exposed to the outside. Because putting the lidar sensor into another structure such as glass or a vehicle body can significantly degrade the sensing performance of the sensor, so it is exposed to the outside and mounted.

For reference, the lidar sensor, as shown in FIG. 2, includes a transmission unit (laser transmission), a reception unit (reflected laser reception), and a driving unit (drives a mirror rotation motor), and protects the sensor from external foreign matter. A cover is added for it. Further, the cover is equipped with a heating wire, and the heating wire is for removing moisture or snow attached to the cover surface.

The angular resolution of the lidar sensor generally has a fairly precise angular resolution of 0.25° or 0.125°, and the angular resolution is determined by synchronizing the rotation speed of the motor and the transmission interval of the laser. For example, in order to scan a laser to have an angular resolution of 1° in a motor that rotates once per second, the laser must be transmitted at intervals of 1/360 seconds to have an angular resolution of exactly 1°. The laser transmission interval can be accurately controlled using the precise clock of the lidar sensor signal processing system, but even if the rotational speed of the motor is controlled as precisely as possible, a rotational speed error of about 1% is generally generated. For example, if a 1% error occurs in the rotational speed of the motor, 1.01 second is required for one rotation. At this time, if the laser scan has an angular resolution of 1°, the laser transmission interval should also be changed to an interval of 1.01/360 seconds.

Accordingly, there is a demand for technology development to prevent an error in the resolution of the laser scan angle of the lidar sensor by adjusting the laser transmission interval even in a situation where there is an error in the speed of the motor.

Background art of the present invention is disclosed in Korean Patent Application Publication No. 2015-0009177 (registered on January 26, 2015, title of the invention: lidar sensor system).

The present invention was devised to improve the above problems, and an object of the present invention is to prevent an error in the resolution of the laser scan angle of the lidar sensor by adjusting the laser transmission interval even in a situation where there is an error in the speed of the motor. It is to provide a sensor scan refinement apparatus and method.

The problem to be solved by the present invention is not limited to the problem(s) mentioned above, and another problem(s) not mentioned will be clearly understood by those skilled in the art from the following description.

A lidar sensor scanning precision apparatus according to an embodiment of the present invention includes a scanner reflector having a magnet and transmitting a laser signal, a motor connected to the scanner reflector and rotating by a control signal to rotate the scanner reflector, A first Hall sensor and a second Hall sensor respectively mounted at a predetermined position of a motor housing equipped with the motor and outputting a first voltage signal and a second voltage signal when the magnet is sensed by rotation of the scanner reflector, the Outputs the control signal for controlling the rotational operation of the motor, and counts the number of laser transmission signals from the time when the first voltage signal is received from the first Hall sensor to the time when the second voltage signal is received from the second Hall sensor And a control unit for adjusting the laser transmission interval based on the counted number of laser transmission signals.

In the present invention, the first Hall sensor may be mounted at a start position of an unscanned area, and the second Hall sensor may be mounted at an end position of an unscanned area.

In the present invention, the control unit may compare the counted number of laser transmission signals with a preset reference number, and adjust the laser transmission interval according to the difference in the number.

In the present invention, when the number of the counted laser transmission signals is greater than the reference number, the control unit reduces the laser transmission interval so that the number of counted laser transmission signals becomes the reference number, and When the number is less than the reference number, the laser transmission interval may be increased so that the number of the counted laser transmission signals becomes the reference number.

In another exemplary embodiment of the present invention, a method for precise scanning of a lidar sensor includes the steps of rotating a scanner reflector by rotating a motor provided in a laser motor housing according to a control signal, and a first control unit mounted at a predetermined position of the motor housing. Determining whether the laser is a scan area to be scanned based on whether the first voltage signal and the second voltage signal from the Hall sensor and the second Hall sensor are received. If the control unit is not the scan area, the laser generated during the unscanned area And counting the number of transmission signals, and adjusting the laser transmission interval based on the counted number of laser transmission signals.

In the step of determining whether the laser is a scan area to be scanned in the present invention, the control unit refers to a scan area from after receiving the second voltage signal from the second Hall sensor to until receiving the first voltage signal from the first Hall sensor. It may be characterized in that it is determined that from a time point when a first voltage signal is received from the first Hall sensor to a time point when a second voltage signal is received from the second Hall sensor is an unscanned region.

In the step of adjusting the laser transmission interval in the present invention, the control unit may compare the counted number of laser transmission signals with a preset reference number, and adjust the laser transmission interval according to the difference in number. have.

In the step of adjusting the laser transmission interval in the present invention, when the number of the counted laser transmission signals is greater than the reference number, the controller reduces the laser transmission interval so that the number of counted laser transmission signals becomes the reference number. If the number of the counted laser transmission signals is less than the reference number, the laser transmission interval may be increased so that the number of the counted laser transmission signals becomes the reference number.

In addition to this, another method for implementing the present invention, another system, and a computer program for executing the method may be further provided.

Other aspects, features, and advantages than those described above will become apparent from the following drawings, claims, and detailed description of the invention.

According to the present invention, based on the number of laser transmission signals generated during an area not scanned by a lidar sensor, by adjusting the laser transmission interval of the area that actually needs to be scanned, even if a rotation error of the motor occurs, it is adjusted to the corresponding rotation speed. Since the laser is transmitted, scan errors can be reduced.

Meanwhile, the effects of the present invention are not limited to the above-mentioned effects, and various effects may be included within a range that is apparent to a person skilled in the art from the contents to be described below.

1 is an exemplary view showing a general field of view (FOV) of a lidar sensor mounted on a front/rear bumper of a vehicle.
2 is an exemplary diagram illustrating a schematic configuration of a previously released lidar sensor.
3 is an exemplary view schematically showing the internal configuration of a lidar sensor according to an embodiment of the present invention.
4 is an exemplary view showing in more detail a sensing light source unit, a light receiving lens, and a light receiving reflector of the lidar sensor in FIG. 3.
5 and 6 are exemplary diagrams for explaining a scan area of a lidar sensor according to an embodiment of the present invention.
7 is an exemplary view showing the scanner unit shown in FIG. 3 in more detail.
8 is an exemplary view for explaining the operation of the scanner unit according to an embodiment of the present invention.
9 is an exemplary view for explaining an area that is not laser scanned according to an embodiment of the present invention.
10 is a view for explaining a LiDAR sensor scan precision apparatus according to an embodiment of the present invention.
11 is a flowchart illustrating a method for refinement of a lidar sensor scan according to an embodiment of the present invention.
12 is a flow chart specifically illustrating a method for refinement of a lidar sensor scan according to an embodiment of the present invention.

Hereinafter, an apparatus and method for refinement of a lidar sensor scan according to an embodiment of the present invention will be described with reference to the accompanying drawings. In this process, the thickness of the lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of description.

In addition, terms to be described later are terms defined in consideration of functions in the present invention and may vary according to the intention or custom of users or operators. Therefore, definitions of these terms should be made based on the contents throughout the present specification.

In addition, the implementation described herein may be implemented in, for example, a method or process, an apparatus, a software program, a data stream or a signal. Although discussed only in the context of a single form of implementation (eg, only as a method), the implementation of the discussed features may also be implemented in other forms (eg, an apparatus or program). The device may be implemented with appropriate hardware, software and firmware. The method may be implemented in an apparatus such as a processor, which generally refers to a processing device including, for example, a computer, microprocessor, integrated circuit or programmable logic device, or the like. Processors also include communication devices such as computers, cell phones, personal digital assistants ("PDAs") and other devices that facilitate communication of information between end-users.

FIG. 3 is an exemplary view schematically showing the internal configuration of a lidar sensor according to an embodiment of the present invention, and FIG. 4 is a more detailed illustration of a sensing light source, a light receiving lens, and a light receiving reflector of the lidar sensor in FIG. 5 and 6 are exemplary diagrams for describing a scan area of a lidar sensor according to an exemplary embodiment of the present invention.

3 and 4, the lidar sensor (or lidar sensing device) according to the present embodiment includes a sensing light source unit 10, a transmission reflector 20, a scanner unit 30, a light receiving lens 40, and It may include a light receiving reflector 50 and a light detection unit 60.

The sensing light source unit 10 may irradiate sensing light. The sensing light source unit 10 may be disposed so as to deviate from the optical path between the light receiving lens 40 and the light receiving reflector 50. Since the sensing light source unit 10 is disposed so as to be out of the optical path between the light receiving lens 40 and the light receiving reflector 50, it is possible to prevent the sensing light source 10 from blocking (shielding: blackage effect) incident light in the optical path. Accordingly, it is possible to prevent generation of a blackage area A by the sensing light source unit 10 in the optical path of the light-receiving lens 40, thereby increasing light receiving efficiency. As the light-receiving efficiency increases as described above, the maximum detection distance of the lidar sensor can be increased.

The sensing light source unit 10 may include a barrel 11, a light source 13, and a light transmitting lens unit 15. The barrel 11 is disposed so as to deviate from the optical path of the light receiving lens 40 and may be formed in a cylindrical shape. The light source 13 may be installed inside the barrel 11. The transmitting lens unit 15 may be installed on the output side of the light source 13 to collimate the sensing light irradiated from the light source 13. Since the transmitting lens unit 15 collimates the sensing light with parallel rays, the output of the sensing light may be improved.

The transmission lens unit 15 may include a first transmission lens 15a and a second transmission lens 15b. The first transmission lens 15a is installed inside the barrel 11, the second transmission lens 15b is installed inside the barrel 11, and the second transmission lens 15b includes a first transmission lens 15a. Sensing light passing through) may be incident. Since the first transmitting lens 15a and the second transmitting lens 15b are installed inside the barrel 11, the first transmitting lens 15a and the second transmitting lens 15b cover the reception of the receiving lens 40 It is possible to prevent the region A from being formed.

The transmission reflector 20 may reflect sensing light irradiated from the sensing light source unit 10. The transmission reflector 20 may be coated with a metal reflective layer (not shown) to improve light reflection efficiency. The light transmitting reflector 20 may be disposed in the optical path of the light receiving lens 40. At this time, since the transmission reflector 20 is disposed in the optical path of the light receiving lens 40, the reception blocking area A may be as much as the width of the transmission reflector 20. Therefore, since the reception blocking area A in the light receiving lens 40 is reduced, light reception efficiency can be increased. Accordingly, as the light receiving efficiency increases, the maximum detection distance of the lidar sensing device may be further increased.

The scanner unit 30 may reflect sensing light reflected from the transmission reflector 20 to the target, and may reflect incident light reflected from the target. A reflective layer may also be formed on the scanner unit 30 to improve light reflection efficiency. The scanner unit 30 may include a scanner reflector 31 and a scanner driver 33.

The scanner reflector 31 may reflect sensing light reflected from the transmission reflector 20 toward the target, and reflect incident light reflected from the target to the light receiving lens 40.

The scanner driving unit 33 may be connected to the scanner reflector 31 to rotate the scanner reflector 31. Since the scanner driving unit 33 rotates the scanner reflector 31, reflection angles of the sensing light and the incident light may be changed according to the angle of the scanner reflector 31.

The scanner unit 30 mounts the scanner reflector 31 to the scanner driver 33 and rotates the scanner reflector 31 to perform laser scanning. When laser scanning is performed using the scanner reflector 31 mounted on the scanner driving unit 33 as described above, a limited area B is scanned as shown in FIG. 5. That is, during laser scanning, the scanner driving unit 33 rotates 360°, but does not scan the entire 360° area, but there is an area C that is covered by the instrument as shown in FIG. 6, and thus there is an area that cannot be scanned. Here, the apparatus may be a component of the lidar sensor itself or an external component.

A detailed description of the scanner unit 30 will be made with reference to FIGS. 7 to 10.

Incident light reflected from the scanner unit 30 is transmitted through the light-receiving lens 40, and the light-receiving lens 40 may be integrally formed with the transmission reflector 20. The light-receiving lens 40 and the light-transmitting reflector 20 may be processed with the same optical material such as crystal, glass, and transparent synthetic resin. The light-receiving lens 40 may be formed with an anti-reflective coating to prevent reflection of incident light. Since the light receiving lens 40 and the light transmitting reflector 20 are integrated into one optical module, the number of parts can be reduced. In addition, it is possible to prevent the reception blocking area A from being formed by the barrel 11.

The light-receiving reflector 50 may reflect incident light that has passed through the light-receiving lens 40. A reflective layer (not shown) may also be formed in the scanner unit 30 to improve light reflection efficiency.

Incident light reflected from the light-receiving reflector 50 may be incident on the photodetector 60. The photodetector 60 may detect the location and distance of the target as incident light is incident.

In addition, the lidar sensor may include an interference filter 63 installed between the light receiving reflector 50 and the light detection unit 60. The interference filter 63 filters light of a specific wavelength, and since the interference filter 63 makes light of a certain wavelength range incident on the light detection unit 60, the position and distance of the target can be accurately detected by the light detection unit 60. I can.

7 is an exemplary diagram showing the scanner unit shown in FIG. 3 in more detail, FIG. 8 is an exemplary diagram for explaining the operation of the scanner unit according to an embodiment of the present invention, and FIG. 9 is an exemplary diagram according to an embodiment of the present invention. An exemplary view for explaining an area that is not laser scanned, FIG. 10 is a diagram for explaining a lidar sensor scan refinement apparatus according to an embodiment of the present invention.

7 to 10, the lidar sensor scan refinement apparatus may include a scanner unit 30 and a control unit 110.

The scanner unit 30 may include a scanner reflector 31 and a scanner driver 33.

The scanner reflector 31 transmits a laser signal, and a magnet 31-1 may be provided. Here, the magnet 31-1 may be provided on the bottom surface of the scanner reflector 31 by crossing the N and S poles.

In addition, the scanner reflector 31 is coupled by a shaft 33-11 that is a part of the motor 33-1 to rotate in the same direction and speed as the motor 33-1. Therefore, the scanner reflector 31 can transmit a laser signal while rotating according to the rotation of the motor 33-1.

The scanner driving unit 33 may include a motor housing 33-2, a motor 33-1 provided in the motor housing 33-2, and a hall sensor 33-3 mounted on an upper surface of the housing. .

The motor housing 33-2 may have a fixed form without rotating.

The motor 33-1 may rotate with a direction (clockwise or counterclockwise) and a speed according to a control signal from the controller 110. In this embodiment, the motor 33-1 may include a shaft 33-11 that is rotatably installed, and a rotor 33-12 that is installed on the shaft 33-11 and rotates together. Since the shaft 33-11 is connected to the scanner reflector 31, a part of the shaft 33-11 is outside the motor housing 33-2, and a part of the shaft 33-11 and the rotor 33- 12) may be provided inside the motor housing 33-2.

The motor 33-1 rotates the scanner reflector 31 while rotating according to a control signal, and the scanner reflector 31 transmits a laser signal at a preset laser transmission interval while rotating.

The angular resolution of the lidar sensor is determined by synchronizing the rotational speed of the motor 33-1 and the transmission interval of the laser, and how many times to transmit the laser while the motor 33-1 rotates 360° according to the angular resolution. It is determined, and the time interval for transmitting the laser is also determined according to the rotational speed of the motor 33-1. Therefore, when the motor 33-1 always rotates at a constant speed, the laser always transmits to a constant position, and scans can always be performed with a constant angular resolution. However, ideally, the rotational speed of the motor 33-1 is constant, but in reality, as long as the rotational error is at least 1% and the laser transmission interval is fixed, the scan error of the lidar sensor is bound to occur. Accordingly, even if an error in the rotational speed of the motor 33-1 occurs, it is necessary to prevent an error in the resolution of the laser scan angle of the lidar sensor.

On the other hand, when laser scanning is performed using the scanner reflector 31 mounted on the motor 33-1, as shown in FIG. 6, there is an area C that cannot be scanned because it is covered by a device. In the present invention, when laser scanning using the scanner reflector 31 mounted on the motor 33-1, an area other than the scan area for detecting an actual object (i.e., an area not scanned) is used during the corresponding area. By determining the current rotational speed of the motor 33-1 and adjusting the transmission interval for laser scanning according to the determined rotational speed of the motor 33-1, a laser scan having more accurate angular resolution may be achieved.

For example, if the rotation of the motor 33-1 is 360°, but the scan area for detecting an object is 180°, the rotational speed of the motor may be determined during the 180° area not scanned. At this time, the laser transmission interval of the area that actually needs to be scanned is adjusted using the determined rotation speed of the motor 33-1, and the laser is transmitted according to the corresponding rotation speed even if a rotation error of the motor 33-1 occurs. There is an effect that can reduce errors.

In order to use the above-described method, it is necessary to determine an area that has not been scanned because it is covered by a device. Accordingly, according to the present invention, Hall sensors 33-3a and 33-3b may be mounted at a predetermined position of the motor housing 33-2. At this time, the Hall sensors 33-3a and 33-3b are mounted at a fixed position on the upper surface of the motor housing 33-2, and at a fixed position between the scanner reflector 31 and the motor housing 33-2. Provided, it marks the start and end of the unscanned area That is, the Hall sensors 33-3a and 33-3b include a first Hall sensor 33-3a indicating the start of an unscanned area, and a second Hall sensor 33-3b indicating the end of an unscanned area ). When the scanner reflector 31 is rotated, the Hall sensors 33-3a and 33-3b may generate a voltage signal by sequentially contacting the N and S poles of the magnet 33-1. Therefore, when the magnet 31-1 is detected by the rotation of the scanner reflector 31, the first Hall sensor 33-3a outputs the first voltage signal to the control unit 110, and the second Hall sensor 33 -3b) outputs a second voltage signal to the controller 110 when the magnet 31-1 is detected by the rotation of the scanner reflector 31. Here, the first voltage signal may be a signal indicating the start of the unscanned region, and the second voltage signal may be a signal indicating the end of the unscanned region.

For example, when the scanner reflector 31 rotates and the first Hall sensor 33-3a detects the magnet 31-1 as shown in FIG. 8A, the first Hall sensor 33-3a Generate a first voltage signal. In addition, when the scanner reflector 31 rotates and the second Hall sensor 33-3b detects the magnet 31-1 as shown in FIG. 8B, the second Hall sensor 33-3b Generate a voltage signal.

The controller 110 generates a control signal for controlling the rotational operation of the motor 33-1 and transmits it to the motor 33-1. In addition, when a voltage signal is received from the hall sensors 33-3a and 33-3b when the scanner reflector 31 is rotated, the control unit 110 determines that the area is not scanned, and the laser generated during the unscanned area The number of transmission signals is counted, and the laser transmission interval is adjusted based on the counted number of laser transmission signals. At this time, the control unit 110 determines that the area is not scanned from the time when the first voltage signal is received from the first Hall sensor 33-3a to the time when the second voltage signal is received from the second Hall sensor 33-3b. can do.

If it is determined that the area is not scanned, the controller 110 counts the number of laser transmission signals generated during the unscanned area, and adjusts the laser transmission interval based on the counted number of laser transmission signals. In this case, the controller 110 compares the counted number of laser transmission signals with a preset reference number, and adjusts the interval of laser transmission according to the difference in the number. That is, if the number of laser transmission signals counted in the non-scanning area is greater than the reference number, this is a situation in which the motor 33-1 rotates slower than the reference speed, and thus the laser transmission interval is also lower than the reference speed to transmit. Conversely, if the number of laser transmission signals counted in the unscanned area is less than the reference number, this is a situation in which the motor 33-1 rotates faster than the reference speed, and thus the laser transmission interval is also higher than the reference speed and transmitted.

In other words, the control unit 110 starts counting the laser transmission signal from the beginning of the area C that is covered by the device of the sensor among the areas scanned by the laser as shown in FIG. 9. The number of transmitted signals counted during that time is determined when the covered area C ends and the scan area B starts again. At this time, each start and end time may be determined using the first Hall sensor 33-3a and the second Hall sensor 33-3b. As the number of detected laser transmission signals is more or less than the reference number, the scan is performed by adjusting the laser transmission interval at the beginning of the scan area. Since the reference laser transmission interval is known in advance, if the laser transmission interval is adjusted by the difference count value, it is synchronized with the rotational speed of the motor 33-1 as much as possible to proceed with the scan without an error in the resolution of the scan angle.

In addition, the controller 110 may control the overall operation state of the lidar sensor stabilization device. Here, the controller 110 may include all kinds of devices capable of processing data, such as a processor. Here, the'processor' may refer to a data processing device embedded in hardware having a circuit physically structured to perform a function represented by a code or instruction included in a program. As an example of a data processing device built into the hardware as described above, a microprocessor, a central processing unit (CPU), a processor core, a multiprocessor, and an application-specific integrated (ASIC) circuit) and processing devices such as field programmable gate arrays (FPGAs), but the scope of the present invention is not limited thereto.

11 is a flowchart illustrating a method for refinement of a lidar sensor scan according to an embodiment of the present invention.

Referring to FIG. 11, the controller 110 outputs a control signal for commanding rotation to the motor 33-1 provided in the lidar sensor, and the motor 33-1 is configured by a control signal from the controller 110. Start rotation (S1110). When the motor 33-1 rotates, the scanner reflector 31 connected to the motor 33-1 also rotates.

When step S1110 is performed, the control unit 110 determines whether or not the laser scan area (S1120). At this time, the control unit 110 may determine that the scan area is a period after the start of the scan and before receiving the voltage signal from the Hall sensor 33-3.

As a result of the determination in step S1120, in the case of the scan area, the controller 110 performs a laser scan (S1130).

As a result of the determination of step S1120, if it is not the scan area, the control unit 110 determines that the area is not scanned and counts the number of laser transmission signals during the unscanned area (S1140), and based on the counted number of laser transmission signals. The laser transmission interval is adjusted (S1150).

12 is a flow chart specifically illustrating a method for refinement of a lidar sensor scan according to an embodiment of the present invention.

Referring to FIG. 12, the control unit 110 outputs a control signal for commanding rotation to the motor 33-1 provided in the lidar sensor, and the motor 33-1 receives the control signal from the control unit 110. Start rotation (S1210). When the motor 33-1 rotates, the scanner reflector 31 connected to the motor 33-1 also rotates.

When step S1210 is performed, the controller 110 determines whether the first voltage signal is received (S1220). Here, the first voltage signal is a signal indicating the start of an unscanned region, and may include first Hall sensor identification information.

If the first voltage signal is not received as a result of the determination in step S1220, the controller 110 determines that it is a scan area and performs a laser scan (S1230).

If, as a result of the determination in step S1220, the first voltage signal is received, the control unit 110 determines that it is an unscanned region and starts counting the number of laser transmission signals (S1240), and determines whether a second voltage signal is received. Do (S1250). Here, the second voltage signal is a signal indicating the end of the unscanned region, and may include second Hall sensor identification information.

As a result of the determination in step S1250, when the second voltage signal is received, the controller 110 determines that the unscanned region is terminated, and adjusts the laser transmission interval based on the number of laser transmission signals counted so far (S1260). .

As described above, the apparatus and method for precision scanning of a lidar sensor according to an embodiment of the present invention, based on the number of laser transmission signals generated during an unscanned region, by adjusting the laser transmission interval of an area that actually needs to be scanned. , Even if a rotation error of the motor occurs, the scan error can be reduced because the laser is transmitted according to the rotation speed.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is only illustrative, and those of ordinary skill in the field to which the technology pertains, various modifications and other equivalent embodiments are possible. I will understand.

Therefore, the true technical protection scope of the present invention should be determined by the following claims.

10: sensing light source unit
20: transmission reflector,
30: scanner unit
31: scanner reflector
31-1: magnet
33: scanner driver
33-1: motor
33-2: motor housing
33-3: Hall sensor
40: light receiving lens
50: light receiving reflector
60: light detection unit
110: control unit

Claims (8)

A scanner reflector that transmits a laser signal and is provided with a magnet;
A motor connected to the scanner reflector and rotated by a control signal to rotate the scanner reflector;
A first Hall sensor and a second Hall sensor respectively mounted at a predetermined position of a motor housing in which the motor is provided, and outputting a first voltage signal and a second voltage signal when the magnet is sensed by rotation of the scanner reflector; And
Outputs the control signal for controlling the rotational operation of the motor, and calculates the number of laser transmission signals from a time point when a first voltage signal is received from the first Hall sensor to a time point when a second voltage signal is received from the second Hall sensor. A control unit that counts and adjusts the laser transmission interval based on the counted number of laser transmission signals
Lidar sensor scan precision device comprising a.
The method of claim 1,
The first Hall sensor is mounted at a start position of an unscanned area, and the second Hall sensor is mounted at an end position of an unscanned area.
The method of claim 1,
The control unit,
Comparing the counted number of laser transmission signals with a preset reference number, and adjusting the laser transmission interval according to a difference in the number of laser transmission signals.
The method of claim 3,
The control unit,
When the number of counted laser transmission signals is greater than the reference number, the laser transmission interval is reduced so that the number of counted laser transmission signals becomes the reference number, and the number of counted laser transmission signals is less than the reference number. In case, the laser transmission interval is increased so that the number of the counted laser transmission signals becomes the reference number.
Rotating the scanner reflector by rotating a motor provided in the motor housing according to a control signal;
Determining, by the controller, whether the laser scan area is based on whether a first voltage signal and a second voltage signal are received from a first Hall sensor and a second Hall sensor mounted at a predetermined position of the motor housing; And
Counting, by the control unit, the number of laser transmission signals generated during an unscanned area if it is not a scan area, and adjusting a laser transmission interval based on the counted number of laser transmission signals
Lidar sensor scan precision method comprising a.
The method of claim 5,
In the step of determining whether the laser is a scan area to be scanned,
The control unit determines that a scan area is a period from after the second voltage signal is received from the second Hall sensor until the first voltage signal is received from the first Hall sensor, and receives the first voltage signal from the first Hall sensor. A lidar sensor scan refinement method, characterized in that it is determined from a point in time to a point in time to receive the second voltage signal from the second Hall sensor as an unscanned area.
The method of claim 5,
In the step of adjusting the laser transmission interval,
The control unit compares the counted number of laser transmission signals with a preset reference number and adjusts according to a difference in the number of laser transmission signals.
The method of claim 7,
In the step of adjusting the laser transmission interval,
When the number of the counted laser transmission signals is greater than the reference number, the control unit reduces the laser transmission interval so that the number of counted laser transmission signals becomes the reference number, and the counted number of laser transmission signals is the reference number. If less than the number, the laser transmission interval is increased so that the number of the counted laser transmission signals becomes the reference number.

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