CN110231497A - A kind of speed calibrating installation to be tested the speed based on laser radar and method - Google Patents

Abstract

The invention provides a vehicle speed calibration device and method based on laser radar speed measurement. The device includes a wheel speed sensor, a laser radar module, a real-time vehicle speed calculation module, a reference vehicle speed calculation module, a calibration information acquisition module and a vehicle speed calibration module. The laser radar echo information is collected by the laser radar module to obtain the reference vehicle speed. The wheel speed information is obtained through the wheel speed sensor, the real-time vehicle speed is calculated, and the reference vehicle speed is compared with the real-time vehicle speed. The comparison between the reference speed and the real-time speed can detect multiple sets of information for verification, and determine whether there is an error in the calculation of the real-time speed. When there is an error in the calculation of the real-time vehicle speed, a calibration coefficient is obtained, and the real-time vehicle speed is calibrated according to the calibration coefficient. The vehicle speed calibration device and method can effectively enhance the accuracy of the input signal of high-speed automatic driving in real time, and greatly improve the level of functional safety.

Description

A vehicle speed calibration device and method based on lidar speed measurement

technical field

The invention relates to the field of electronic appliances, in particular to a vehicle speed calibration device and method based on laser radar speed measurement.

Background technique

As the basic component of the car, the wheel speed sensor is mainly used to measure the wheel speed and calculate the actual speed, and it is an important parameter in the running process of the whole vehicle. For modern automobiles, wheel speed information is essential. Vehicle dynamic control systems, automotive electronic stability programs, anti-lock braking systems, and automatic transmission control systems all require wheel speed information. Therefore, the wheel speed sensor is one of the most critical sensors in modern cars. In the field of active safety, its measurement results are used to calculate the absolute speed of moving objects in the surrounding environment of the car, as a decision-making condition for active safety functions, which directly affects the accuracy and functional safety level of each function.

Generally speaking, all speed sensors can be used as wheel speed sensors, but considering the actual factors such as the working environment of the wheel and the size of the space, the commonly used wheel speed sensors mainly include: magnetoelectric wheel speed sensor, Hall wheel speed sensor . Although the Hall-type wheel speed sensor makes up for the shortcomings of the magnetoelectric wheel speed sensor's low frequency response and poor anti-electromagnetic wave interference ability, it still cannot avoid the deformation of the tire under the wind resistance pressure when driving at high speed; In the case of tilting, the calculation error is increased, resulting in the inaccuracy of the wheel speed sensor to measure the longitudinal speed of the vehicle.

The speed of the ego vehicle plays a crucial role in the state judgment and control decision-making of related functions of high-speed automatic driving, and is an important factor affecting the safety of high-speed automatic driving functions. Although the wheel speed sensor has been developed more maturely, there is still no accurate calculation method for the deformation of the tire due to wind resistance pressure, load change, and road excitation when driving at high speed. Therefore, there is still a certain error in the wheel speed sensor.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is the problem of error in the wheel speed sensor during high-speed driving. In order to solve the above problems, the present invention proposes a vehicle speed calibration device and method based on lidar speed measurement. The present invention is specifically implemented by the following technical solutions:

A first aspect of the present invention provides a vehicle speed calibration device based on lidar speed measurement, the device includes: a wheel speed sensor, a lidar module, a real-time vehicle speed calculation module, a reference vehicle speed calculation module, a calibration information acquisition module, and a vehicle speed calibration module module;

The wheel speed sensor is used to obtain real-time wheel speed information;

The lidar module is used for sending laser information and receiving lidar echo information;

The real-time vehicle speed calculation module is used to calculate the real-time vehicle speed according to the wheel speed information;

The reference vehicle speed calculation module is used for calculating the reference vehicle speed according to the lidar echo information;

The wheel speed sensor state judging module is used to compare the real-time vehicle speed with the reference vehicle speed, and determine whether there is an error in the wheel speed sensor;

The calibration information obtaining module is used to obtain a calibration coefficient when it is judged that the wheel speed sensor has a calculation error;

The vehicle speed calibration module is used for calibrating the real-time vehicle speed according to the obtained calibration information.

Further, the laser radar module includes a laser information sending unit, a radar echo receiving unit and an information processing unit. The resolution of the laser radar is high enough, the detection period is shorter than the transmission period of the vehicle speed signal of the wheel speed sensor, and the target classification function can be realized.

The laser information sending unit is used for sending laser information;

The radar echo receiving unit is used for receiving radar echo information;

The information processing unit is used for processing radar echo information to obtain motion state information of obstacles.

Further, the reference vehicle speed calculation module is used for determining whether the obstacle is a stationary object according to the motion state information of the obstacle, and comparing the relative speed between the stationary object and the vehicle to obtain the reference vehicle speed.

Further, the wheel speed sensor state judging module includes a longitudinal vehicle speed obtaining unit and a vehicle speed comparing unit;

The longitudinal vehicle speed obtaining unit is used to extract the speed information of the real-time vehicle speed in the direction of the longitudinal axis of the vehicle as the real-time longitudinal vehicle speed according to the reference vehicle speed and the real-time vehicle speed, and extract the speed information of the reference vehicle speed in the direction of the longitudinal axis of the vehicle as the reference longitudinal vehicle speed;

The vehicle speed comparison unit is used to compare the real-time longitudinal vehicle speed with the reference longitudinal vehicle speed, and determine whether there is an error in the calculation result of the real-time vehicle speed.

Further, the calibration information obtaining module can obtain the calibration coefficient according to the longitudinal reference vehicle speed and the longitudinal real-time vehicle speed when judging that the vehicle speed signal of the current wheel speed sensor has a calculation error.

Specifically, when it is determined that the vehicle speed signal of the current wheel speed sensor has a calculation error, the calibration coefficient is obtained according to the longitudinal reference vehicle speed and the longitudinal real-time vehicle speed.

When it is judged that there is a calculation error in the vehicle speed signal of the current wheel speed sensor, the concept of correction coefficient of the wheel speed sensor is introduced, which is represented by K, the initial value of the correction coefficient is 1, and the range of the current calibration coefficient is assumed to be [0.95, 1.05]. The calibration coefficient range should be determined according to the ASIL level of the lidar signal. The higher the ASIL level, the larger the calibration coefficient range.

The judgment of the state of the wheel speed sensor should include at least the following states. Take the real-time vehicle speed detected by the wheel speed sensor as an example of 100km/h, as shown in the following table:

real-time speed reference speed Calibration factor Warning information 100 0～90 wheel speed sensor failure 100 90～98 K 100 98～102 1 100 102～110 K 100 110～200 wheel speed sensor failure

Among them, the value of K is related to the speed difference of the two sensors:

In the formula, V2 represents the reference longitudinal vehicle speed, and V1 represents the real-time longitudinal vehicle speed.

When the longitudinal vehicle speed detected by the lidar and the wheel speed sensor has a large difference, the system prompts the wheel speed sensor to fail. When the speed difference is within a certain range, the calibration coefficient is calculated from the speed difference and the current vehicle speed. The sensor is considered to be in good condition, and the measured longitudinal vehicle speed value does not require calibration.

According to the calibration information, the real-time vehicle speed is calibrated. After the calibration, continue to compare the reference longitudinal vehicle speed with the real-time longitudinal vehicle speed. When the relative error is less than 2% for more than 3 signal periods, the calibration is considered successful, otherwise the above calibration process will be repeated.

A second aspect of the present invention provides a vehicle speed calibration method based on lidar speed measurement, the method comprising:

Get wheel speed information;

Obtain real-time vehicle speed according to wheel speed information;

Obtain the radar echo information of the lidar, and obtain the reference speed according to the radar echo information;

Compare the real-time vehicle speed with the reference vehicle speed to determine whether there is a calculation error in the real-time vehicle speed;

When it is judged that there is a calculation error in the real-time vehicle speed, the calibration coefficient is obtained;

According to the calibration coefficient, the real-time vehicle speed is calibrated.

Further, the real-time longitudinal vehicle speed of the real-time vehicle speed is obtained, the reference longitudinal vehicle speed of the reference vehicle speed is obtained, and the real-time longitudinal vehicle speed and the reference longitudinal vehicle speed are compared to determine whether there is a calculation error in the real-time longitudinal vehicle speed.

Further, the obtained real-time longitudinal vehicle speed is compared with the reference longitudinal vehicle speed, and when the state of the error greater than the predetermined value continues for a certain number of signal cycles, it is determined that there is a calculation error in the real-time longitudinal vehicle speed.

Further, after judging that there is a calculation error in the real-time longitudinal vehicle speed, a calibration coefficient is obtained according to the real-time longitudinal vehicle speed and the reference longitudinal vehicle speed.

Further, after calibrating the real-time vehicle speed according to the calibration coefficient, the reference longitudinal vehicle speed and the real-time longitudinal vehicle speed are continuously compared, and when the error is less than the preset value and exceeds a certain number of signal periods, it is determined that the real-time vehicle speed calibration is successful.

Specifically, when it is determined that the vehicle speed signal of the current wheel speed sensor has a calculation error, the calibration coefficient is obtained according to the longitudinal reference vehicle speed and the longitudinal real-time vehicle speed.

When it is judged that there is a calculation error in the vehicle speed signal of the current wheel speed sensor, the concept of correction coefficient of the wheel speed sensor is introduced, which is represented by K, the initial value of the correction coefficient is 1, and the range of the current calibration coefficient is assumed to be [0.95, 1.05]. The calibration coefficient range should be determined according to the ASIL level of the lidar signal. The higher the ASIL level, the larger the calibration coefficient range.

The judgment of the state of the wheel speed sensor should include at least the following states. Take the real-time vehicle speed detected by the wheel speed sensor as an example of 100km/h, as shown in the following table:

Among them, the value of K is related to the speed difference of the two sensors:

In the formula, V2 represents the reference longitudinal vehicle speed, and V1 represents the real-time longitudinal vehicle speed.

When the longitudinal vehicle speed detected by the lidar and the wheel speed sensor has a large difference, the system prompts the wheel speed sensor to fail. When the speed difference is within a certain range, the calibration coefficient is calculated from the speed difference and the current vehicle speed. The sensor is considered to be in good condition, and the measured longitudinal vehicle speed value does not require calibration.

According to the calibration information, the real-time vehicle speed is calibrated. After the calibration, continue to compare the reference longitudinal vehicle speed with the real-time longitudinal vehicle speed. When the relative error is less than 2% for more than 3 signal periods, the calibration is considered successful, otherwise the above calibration process will be repeated.

By adopting the above technical solution, the vehicle speed calibration device and method based on laser radar speed measurement according to the present invention has the following beneficial effects:

1) The present invention proposes a vehicle speed calibration device and method based on lidar speed measurement. The vehicle speed calibration device detects the speed of the own vehicle through lidar, obtains an accurate reference vehicle speed, and compares the reference vehicle speed with that calculated by the wheel speed information. Real-time vehicle speed, get the calibration coefficient to calibrate the real-time vehicle speed, avoid the tire deformation caused by wind resistance pressure, load change, road excitation and the inability to accurately calculate the vehicle speed when driving at high speed;

2) The present invention proposes a vehicle speed calibration device and method based on lidar speed measurement. The speed measurement by lidar can effectively enhance the accuracy of the input signal of high-speed automatic driving in real time, and greatly improve the level of functional safety.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

1 is a schematic structural diagram of a vehicle speed calibration device based on lidar speed measurement provided by an embodiment of the present invention;

2 is a schematic structural diagram of a lidar module of a vehicle speed calibration device based on lidar speed measurement provided by an embodiment of the present invention;

3 is a schematic structural diagram of a lidar module of a vehicle speed calibration device based on lidar speed measurement provided by an embodiment of the present invention;

FIG. 4 is a flowchart of a method for calibrating vehicle speed based on lidar speed measurement according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

In the several embodiments provided in this application, the described system embodiments are only illustrative. For example, the division of the modules is only a logical function division. In actual implementation, there may be other division methods, such as Multiple modules or components may be combined or may be integrated into another system, or some features may be omitted, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of modules or units, and may be in electrical or other forms.

The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, may be located in one place, or may be distributed to multiple network modules. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

Example 1:

An embodiment of the present invention provides a vehicle speed calibration device based on lidar speed measurement. As shown in FIG. 1 , the device includes: a wheel speed sensor, a lidar module, a real-time vehicle speed calculation module, a reference vehicle speed calculation module, and a calibration information acquisition module. module and vehicle speed calibration module.

The wheel speed sensor is used to obtain real-time wheel speed information;

The lidar module is used to obtain lidar echo information;

The real-time vehicle speed calculation module is used to calculate the real-time vehicle speed according to the wheel speed information;

The reference vehicle speed calculation module is used for calculating the reference vehicle speed according to the lidar echo information;

The wheel speed sensor state judging module is used to compare the real-time vehicle speed with the reference vehicle speed, and determine whether there is an error in the wheel speed sensor;

The calibration information obtaining module is used to obtain a calibration coefficient when it is judged that the wheel speed sensor has a calculation error;

The vehicle speed calibration module is used for calibrating the real-time vehicle speed according to the obtained calibration information.

Further, when the vehicle is running, the wheel speed sensor obtains the wheel speed information, and the real-time vehicle speed calculation module can calculate the real-time vehicle speed according to the wheel speed information and the rolling radius.

Further, as shown in FIG. 2 , the lidar module includes a laser information sending unit, a radar echo receiving unit and an information processing unit. The resolution of the laser radar is high enough, the detection period is shorter than the transmission period of the vehicle speed signal of the wheel speed sensor, and the target classification function can be realized.

The laser information sending unit is used for sending laser information;

The radar echo receiving unit is used for receiving radar echo information;

The information processing unit is used for processing radar echo information to obtain motion state information of obstacles.

The reference vehicle speed calculation module is used for determining whether the obstacle is a stationary object according to the motion state information of the obstacle, and comparing the relative speed between the stationary object and the vehicle to obtain the reference vehicle speed.

Further, as shown in FIG. 3 , the wheel speed sensor state judging module includes a longitudinal vehicle speed obtaining unit and a vehicle speed comparing unit. The longitudinal vehicle speed obtaining unit is used for extracting the speed information of the real-time vehicle speed in the direction of the longitudinal axis of the vehicle as the real-time longitudinal vehicle speed according to the reference vehicle speed and the real-time vehicle speed, and extracting the speed information of the reference vehicle speed in the direction of the longitudinal axis of the vehicle as the reference longitudinal vehicle speed.

The vehicle speed comparison unit is used to compare the real-time longitudinal vehicle speed with the reference longitudinal vehicle speed, and determine whether there is an error in the calculation result of the real-time vehicle speed. When the error is too large, a warning message will be sent, indicating that the wheel speed sensor is faulty.

Further, the calibration information obtaining module is configured to obtain a calibration coefficient according to the longitudinal reference vehicle speed and the longitudinal real-time vehicle speed when it is determined that the vehicle speed signal of the current wheel speed sensor has a calculation error.

Specifically, when the vehicle is running, the wheel speed sensor obtains wheel speed information, and the real-time vehicle speed calculation module can calculate the real-time vehicle speed according to the wheel speed information and the rolling radius.

The LiDAR module calculates the distance and azimuth angle between the obstacle and the vehicle by accurately measuring the propagation time of the light wave pulse from the transmission to the reflection; calculates the relative distance between the vehicle and the obstacle through the phase difference between the received and transmitted light wave pulses Speed; according to the signal strength of the received light, the obstacle area is divided; by tracking the signals of each group of received light, it is judged whether the currently received light signal is feedback from the obstacle, and then according to the size, shape, speed and confidence of the obstacle. The motion state of the obstacle is classified.

By comparing the states of obstacles in multiple groups, it is determined whether the current obstacle is a stationary object or a moving object. The absolute speed of the ego vehicle can be obtained by comparing the relative speed between the stationary object and the ego vehicle. The absolute vehicle speed of the ego vehicle is used as the reference vehicle speed.

The longitudinal vehicle speed obtaining unit extracts the speed information of the wheel speed in the direction of the longitudinal axis of the vehicle as the real-time longitudinal vehicle speed, and extracts the reference longitudinal vehicle speed of the reference vehicle speed obtained by the lidar module. Comparing the obtained real-time longitudinal speed with the reference longitudinal speed, if the difference is greater than 2% for 3 signal periods, it is considered that there is a calculation error in the real-time speed, and the real-time speed needs to be calibrated.

When it is judged that there is a calculation error in the vehicle speed signal of the current wheel speed sensor, the concept of correction coefficient of the wheel speed sensor is introduced, which is represented by K, the initial value of the correction coefficient is 1, and the range of the current calibration coefficient is assumed to be [0.95, 1.05]. The calibration coefficient range should be determined according to the ASIL level of the lidar signal. The higher the ASIL level, the larger the calibration coefficient range.

The judgment of the state of the wheel speed sensor should include at least the following states. Take the real-time vehicle speed detected by the wheel speed sensor as an example of 100km/h, as shown in the following table:

real-time speed reference speed Calibration factor Warning information 100 0～90 wheel speed sensor failure 100 90～98 K 100 98～102 1 100 102～110 K 100 110～200 wheel speed sensor failure

Among them, the value of K is related to the speed difference of the two sensors:

In the formula, V2 represents the reference longitudinal vehicle speed, and V1 represents the real-time longitudinal vehicle speed.

When the longitudinal vehicle speed detected by the lidar and the wheel speed sensor has a large difference, the system prompts the wheel speed sensor to fail. When the speed difference is within a certain range, the calibration coefficient is calculated from the speed difference and the current vehicle speed. The sensor is considered to be in good condition, and the measured longitudinal vehicle speed value does not require calibration.

The vehicle speed calibration module calibrates the real-time vehicle speed according to the calibration information. After the calibration, continue to compare the reference longitudinal vehicle speed with the real-time longitudinal vehicle speed. When the relative error is less than 2% for more than 3 signal periods, the calibration is considered successful, otherwise the above calibration process will be repeated.

This embodiment proposes a vehicle speed calibration device based on lidar speed measurement. The vehicle speed calibration device has a laser radar, and the laser radar can obtain a reference vehicle speed by detecting obstacles. The wheel speed sensor obtains wheel speed information, and obtains the real-time vehicle speed according to the wheel speed information. Compare the real-time vehicle speed with the reference vehicle speed. If the error is greater than a certain value, the real-time vehicle speed is calibrated. The vehicle speed calibration device can calibrate the vehicle speed measured by the wheel speed sensor through the vehicle speed measured by the laser radar, so as to avoid errors in the measurement of the wheel speed sensor due to the deformation of the tire during high-speed driving, and the measured vehicle speed is more accurate, ensuring that Driving safety and improving the driving experience.

Example 2:

A feasible embodiment of the present invention provides a vehicle speed calibration method based on lidar speed measurement. Specifically, as shown in FIG. 4 , the vehicle speed calibration method based on lidar speed measurement includes:

S1. Obtain wheel speed information, and obtain real-time vehicle speed according to the wheel speed information;

S2. Obtain the radar echo information of the lidar, and obtain the reference vehicle speed according to the radar echo information;

S3. Obtain the real-time longitudinal vehicle speed of the real-time vehicle speed, and obtain the reference longitudinal vehicle speed of the reference vehicle speed;

S4. Compare the real-time longitudinal vehicle speed with the reference longitudinal vehicle speed, and determine whether there is a calculation error in the real-time longitudinal vehicle speed;

S5. When it is judged that there is a calculation error in the real-time longitudinal vehicle speed, a calibration coefficient is obtained according to the real-time longitudinal vehicle speed and the reference longitudinal vehicle speed;

S6. According to the calibration coefficient, the real-time vehicle speed is calibrated.

Further, after the calibration, the reference longitudinal vehicle speed and the real-time longitudinal vehicle speed are continued to be compared. When the relative error is less than 2% for more than 3 signal periods, the calibration is considered successful, otherwise the above calibration process will be repeated.

Specifically, when the vehicle is running, the wheel speed sensor obtains the wheel speed information, and calculates the real-time vehicle speed according to the wheel speed information and the rolling radius.

Lidar calculates the distance and azimuth angle between the obstacle and the vehicle by accurately measuring the propagation time of the light wave pulse from transmission to being reflected back; calculates the relative speed between the vehicle and the obstacle by the phase difference between the received and transmitted light wave pulses ; According to the signal strength of the received light, divide the obstacle area; by tracking each group of received light signals, determine whether the currently received light signal is obstacle feedback, and then according to the size, shape, speed and confidence of the obstacle. The state of motion of objects is classified.

By comparing the states of obstacles in multiple groups, it is determined whether the current obstacle is a stationary object or a moving object. The absolute speed of the ego vehicle can be obtained by comparing the relative speed between the stationary object and the ego vehicle. The absolute vehicle speed of the ego vehicle is used as the reference vehicle speed.

According to the reference vehicle speed and the real-time vehicle speed, the speed information of the real-time vehicle speed in the direction of the vehicle longitudinal axis is extracted as the real-time longitudinal vehicle speed, and the speed information of the reference vehicle speed in the direction of the vehicle longitudinal axis is extracted as the reference longitudinal vehicle speed.

Compare the real-time longitudinal vehicle speed with the reference longitudinal vehicle speed to determine whether there is an error in the calculation result of the real-time vehicle speed. Comparing the obtained real-time longitudinal vehicle speed with the reference longitudinal vehicle speed, if the difference is greater than 2% for 3 signal periods, it is considered that there is a calculation error in the real-time vehicle speed. Real-time vehicle speed needs to be calibrated. When the error is too large, a warning message will be sent, indicating that the wheel speed sensor is faulty.

When it is determined that the vehicle speed signal of the current wheel speed sensor has a calculation error, a calibration coefficient is obtained according to the longitudinal reference vehicle speed and the longitudinal real-time vehicle speed.

When it is judged that there is a calculation error in the vehicle speed signal of the current wheel speed sensor, the concept of correction coefficient of the wheel speed sensor is introduced, which is represented by K, the initial value of the correction coefficient is 1, and the range of the current calibration coefficient is assumed to be [0.95, 1.05]. The calibration coefficient range should be determined according to the ASIL level of the lidar signal. The higher the ASIL level, the larger the calibration coefficient range.

The judgment of the state of the wheel speed sensor should include at least the following states. Take the real-time vehicle speed detected by the wheel speed sensor as an example of 100km/h, as shown in the following table:

real-time speed reference speed Calibration factor Warning information 100 0～90 wheel speed sensor failure 100 90～98 K 100 98～102 1 100 102～110 K 100 110～200 wheel speed sensor failure

Among them, the value of K is related to the speed difference of the two sensors:

In the formula, V2 represents the reference longitudinal vehicle speed, and V1 represents the real-time longitudinal vehicle speed.

When the longitudinal vehicle speed detected by the lidar and the wheel speed sensor has a large difference, the system prompts the wheel speed sensor to fail. When the speed difference is within a certain range, the calibration coefficient is calculated from the speed difference and the current vehicle speed. The sensor is considered to be in good condition, and the measured longitudinal vehicle speed value does not require calibration.

According to the calibration information, the real-time vehicle speed is calibrated. After the calibration, continue to compare the reference longitudinal vehicle speed with the real-time longitudinal vehicle speed. When the relative error is less than 2% for more than 3 signal periods, the calibration is considered successful, otherwise the above calibration process will be repeated.

This embodiment proposes a vehicle speed calibration method based on lidar speed measurement. The vehicle speed calibration device has a laser radar, and the laser radar can obtain a reference vehicle speed by detecting obstacles. The wheel speed sensor obtains wheel speed information, and obtains the real-time vehicle speed according to the wheel speed information. Compare the real-time vehicle speed with the reference vehicle speed. If the error is greater than a certain value, the real-time vehicle speed is calibrated. The vehicle speed calibration method can calibrate the vehicle speed measured by the wheel speed sensor through the vehicle speed measured by the laser radar, so as to avoid errors in the measurement of the wheel speed sensor caused by the deformation of the tire during high-speed driving, and the measured vehicle speed is more accurate, ensuring that Driving safety and improving the driving experience.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (10)

1. a vehicle speed calibration device based on lidar speed measurement, is characterized in that, described device comprises: wheel speed sensor, lidar module, real-time vehicle speed calculation module, reference vehicle speed calculation module, calibration information acquisition module and vehicle speed calibration module; The wheel speed sensor is used to obtain real-time wheel speed information; The lidar module is used for sending laser information and receiving lidar echo information; The real-time vehicle speed calculation module is used to calculate the real-time vehicle speed according to the wheel speed information; The reference vehicle speed calculation module is used for calculating the reference vehicle speed according to the lidar echo information; The wheel speed sensor state judging module is used to compare the real-time vehicle speed with the reference vehicle speed, and determine whether there is an error in the wheel speed sensor; The calibration information obtaining module is used to obtain a calibration coefficient when it is judged that the wheel speed sensor has a calculation error; The vehicle speed calibration module is used for calibrating the real-time vehicle speed according to the obtained calibration information. 2. A vehicle speed calibration device based on lidar speed measurement according to claim 1, wherein the lidar module comprises a laser information sending unit, a radar echo receiving unit and an information processing unit; The laser information sending unit is used for sending laser information; The radar echo receiving unit is used for receiving radar echo information; The information processing unit is used for processing radar echo information to obtain motion state information of obstacles. 3. a kind of vehicle speed calibration device based on lidar speed measurement according to claim 2, is characterized in that, described reference vehicle speed calculation module is used for according to the motion state information of obstacle, judges whether obstacle is static object, contrast static The relative speed between the object and the vehicle to obtain the reference vehicle speed. 4. A vehicle speed calibration device based on lidar speed measurement according to claim 1, wherein the wheel speed sensor state judgment module comprises a longitudinal vehicle speed obtaining unit and a vehicle speed comparison unit; The longitudinal vehicle speed obtaining unit is used to extract the speed information of the real-time vehicle speed in the direction of the longitudinal axis of the vehicle as the real-time longitudinal vehicle speed according to the reference vehicle speed and the real-time vehicle speed, and extract the speed information of the reference vehicle speed in the direction of the longitudinal axis of the vehicle as the reference longitudinal vehicle speed; The vehicle speed comparison unit is used to compare the real-time longitudinal vehicle speed with the reference longitudinal vehicle speed, and determine whether there is an error in the calculation result of the real-time vehicle speed. 5 . The vehicle speed calibration device based on lidar speed measurement according to claim 4 , wherein the calibration information obtaining module can determine that the vehicle speed signal of the current wheel speed sensor has a calculation error according to the longitudinal reference vehicle speed. 6 . and longitudinal real-time vehicle speed to obtain calibration coefficients. 6. A vehicle speed calibration method based on lidar speed measurement, wherein the method comprises: Get wheel speed information; Obtain real-time vehicle speed according to wheel speed information; Obtain the radar echo information of the lidar, and obtain the reference speed according to the radar echo information; Compare the real-time vehicle speed with the reference vehicle speed to determine whether there is a calculation error in the real-time vehicle speed; When it is judged that there is a calculation error in the real-time vehicle speed, the calibration coefficient is obtained; According to the calibration coefficient, the real-time vehicle speed is calibrated. 7. a kind of vehicle speed calibration method based on lidar speed measurement according to claim 6, is characterized in that, obtain the real-time longitudinal vehicle speed of real-time vehicle speed, obtain the reference longitudinal vehicle speed of reference vehicle speed, contrast real-time longitudinal vehicle speed and reference longitudinal vehicle speed, judge Whether there is a calculation error in the real-time longitudinal vehicle speed. 8. a kind of vehicle speed calibration method based on lidar speed measurement according to claim 7, is characterized in that, the real-time longitudinal vehicle speed obtained is compared with the reference longitudinal vehicle speed, when the state of the error greater than the predetermined value continues for a certain number of signal cycles , judging that there is a calculation error in the real-time longitudinal vehicle speed. 9 . The vehicle speed calibration method based on lidar speed measurement according to claim 8 , wherein after judging that there is a calculation error in the real-time longitudinal vehicle speed, a calibration coefficient is obtained according to the real-time longitudinal vehicle speed and the reference longitudinal vehicle speed. 10 . 10. A vehicle speed calibration method based on lidar speed measurement according to claim 7, wherein after calibrating the real-time vehicle speed according to the calibration coefficient, the reference longitudinal vehicle speed and the real-time longitudinal vehicle speed are continuously compared, and when the error is less than the preset value When the state exceeds a certain number of signal cycles, it is judged that the real-time vehicle speed calibration is successful.