A method of dynamically measuring the height of a vehicle's fender and chassis

Abstract

The application relates to the technical field of automobile testing, and discloses a method for dynamically measuring the wheel arch and chassis height of a vehicle, which comprises the following steps: a device installation step, in which a laser ranging sensor assembly is installed at a preset position of a vehicle measuring point, and the position and pose of the laser ranging sensor assembly are adjusted; a data collection step, in which laser ranging sensor data and vehicle position and inertia data are collected in real time and synchronously triggered; a measurement time point acquisition step, in which required measurement time points are acquired in real time based on the inertia data; and a ground clearance acquisition step, in which the vertical ground clearance of the measuring point is calculated based on a preset model according to the measuring point laser sensor data, the vehicle position and inertia data and the required measurement time points. The application can dynamically measure the wheel arch and chassis ground clearance of the vehicle in real time, and the measurement precision is higher, and the device assembly is more convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile testing, and in particular to a method for dynamically measuring the height of a vehicle wheel arch and chassis. Background Art

[0002] With the rapid development of intelligent transportation systems and autonomous driving technologies, vehicles are becoming increasingly safer, more comfortable, and more intelligent. Accurately measuring key vehicle parameters, such as wheel arch and chassis height, has become crucial in these advanced transportation systems. While traditional static measurement methods can provide relatively accurate results when the vehicle is stationary, they cannot accurately reflect the vehicle's true state in real time due to factors such as dynamic changes in the suspension system, body movement caused by uneven road surfaces, and changes in vehicle speed. Therefore, real-time dynamic measurement of vehicle wheel arch and chassis ground clearance has significant practical significance and technical value. Summary of the Invention

[0003] The present invention aims to provide a method for dynamically measuring the height of a vehicle's wheel arch and chassis, so as to dynamically measure the height of the vehicle's wheel arch and chassis from the ground in real time, with higher measurement accuracy and easier equipment assembly.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for dynamically measuring the wheel arch and chassis height of a vehicle, comprising:

[0006] Equipment installation steps: install the laser ranging sensor assembly to the preset position of the vehicle measurement point and adjust the position of the laser ranging sensor assembly;

[0007] Data collection step: real-time synchronous triggering to collect laser ranging sensor data and vehicle position and inertia data;

[0008] A measurement time point acquisition step, obtaining the required measurement time point in real time based on the inertia data;

[0009] The ground clearance acquisition step calculates the vertical ground clearance of the measurement point based on the desired measurement time point, according to the laser sensor data of the measurement point and the vehicle position and inertia data based on a preset model.

[0010] The principle and advantages of this solution are: in actual application, the laser ranging sensor assembly is installed at the preset position of the vehicle measurement point, which is convenient for accurately obtaining vehicle information, so as to perform simulation calculations based on the measurement data and further improve vehicle performance; in the existing technical solution, the vehicle body inertial navigation and the laser ranging sensor are arranged separately, and only the gyroscope is placed at an unfixed position on the vehicle for measurement. However, the center of mass of the vehicle continues to change during movement, resulting in inaccurate gyroscope measurement, and it is difficult to accurately measure the relative position of the inertial navigation and the vehicle body laser sensor, which is easy to cause measurement errors. In addition, the accuracy of the inertial navigation acquisition angle is not high, which also causes measurement errors; in this application, the wheel arch height is measured by integrating a laser ranging sensor, and the sensor and the inertial navigation system are triggered synchronously to record data at the same time in real time to ensure that the vehicle wheel arch height measurement value is consistent with the inertial navigation measurement parameters, avoiding the problem of inaccurate measurement due to the gyroscope being placed in an unfixed position and the center of mass constantly changing, and the subsequent data analysis is more accurate.

[0011] Preferably, as an improvement, the preset model is:

[0012]

[0013] Where θ is the angle between the two light beams, a and b are the measurement values ​​of the two laser sensors, and Z is the height above the ground measured in real time.

[0014] Technical effect: easy to quickly obtain the height above the ground.

[0015] Preferably, as an improvement, the laser ranging sensor assembly includes two laser ranging sensors, and the rays of the two laser ranging sensors form a fixed and known angle in the projection plane.

[0016] Technical effect: It is easy to obtain the vertical height from the ground and reduce the angle error caused by pitch.

[0017] Preferably, as an improvement, the angle range is 0° to 90°.

[0018] Technical effect: It is easy to ensure that the light beam of the laser sensor hits the ground.

[0019] Preferably, as an improvement, in the equipment installation step, the laser ranging sensor assembly is horizontal along the direction of the vehicle body, the intersection of the projections of the laser beams of the two laser ranging sensors in the laser ranging sensor assembly in the plane coincides with the projections of the emission points of the laser beams of the two laser ranging sensors in the plane, and the starting position of the laser beam coincides with the measuring point.

[0020] Technical effect: It is easy to improve the installation standardization and accuracy of laser sensors, thereby reducing the difficulty of calibration and improving the accuracy of subsequent calculations.

[0021] Preferably, as an improvement, the required measurement time point is the time when the vehicle reaches the collision point.

[0022] Technical effect: Facilitates vehicle safety optimization analysis.

[0023] Preferably, as an improvement, in the measurement time point acquisition step, imc FAMOSProfessional processing software is used to use the pos function to find the required measurement time point in real time, and the value function is used to analyze the value of each channel at that time.

[0024] Technical effect: Facilitates seamless integration of laser sensors and CAN data. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of a flow chart of an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the installation position of the laser ranging sensor assembly according to an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of codes for obtaining measurement time points required by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following is further described in detail through specific implementation methods:

[0029] The embodiment is basically as shown in the attached Figure 1 As shown, a method for dynamically measuring the wheel arch and chassis height of a vehicle includes:

[0030] The equipment installation step is to install the laser ranging sensor assembly to the preset position of the vehicle measurement point and adjust the laser ranging sensor assembly posture. In this embodiment, the preferred measurement points include the vehicle wheel arch and chassis. Therefore, the laser ranging sensor assembly is installed at the measurement point positions of the four wheel arches and chassis, such as Figure 2 As shown, the wheel arch contains four sets of laser ranging sensor components (eight laser ranging sensors), and the chassis contains one set of laser ranging sensor components (two laser ranging sensors).

[0031] In order to improve the measurement accuracy, the laser ranging sensor assembly in this embodiment includes two laser ranging sensors. The rays of the two laser ranging sensors form a fixed and known angle in the projection plane, and the angle range is 0° to 90° to ensure that the light beam of the laser sensor hits the ground.

[0032] During installation, the laser ranging sensor assembly is horizontally aligned with the vehicle body. The intersection of the projections of the laser beams from the two laser ranging sensors in the assembly coincides with the projections of the emission points of the two laser ranging sensors in the plane. The starting positions of the laser beams also coincide with the measurement points. In this solution, as long as the two laser ranging sensors are within their range, horizontality around the Y axis is not a concern, eliminating one less direction to consider than existing solutions.

[0033] The data collection step is to synchronously trigger the collection of laser ranging sensor data and vehicle position and inertia data in real time to ensure that the vehicle wheel arch height measurement value is consistent with the inertial navigation measurement parameters (vehicle speed, vehicle acceleration in all directions).

[0034] Specifically, the inertial navigation system is arranged at the rear of the center aisle in the vehicle according to the AEB test requirements. The driving robot outputs the vehicle's position and speed information in the form of CAN signals and transmits them to the CAN signal collector. The data of the laser ranging sensor is collected by the sensor data collector, and the CAN signal collector and the sensor data collector are triggered and collected synchronously to facilitate the calculation of the ground height of the measuring point by combining the pitch and roll angles measured by the inertial navigation system and the distance measured by the laser ranging sensor.

[0035] The measurement time point acquisition step is to obtain the required measurement time point in real time based on the inertia data. The required measurement time point is the moment when the vehicle reaches the collision point, that is, the moment when the relative longitudinal distance is 0. After the CAN signal acquisition instrument outputs the data, it is processed using imcFAMOS Professional software, such as Figure 3 As shown in the figure, the POS function is used to find the required measurement time point in real time, and the VALUE function is used to analyze the value of each channel at that time, so as to facilitate the seamless integration of laser sensors and CAN data.

[0036] The ground clearance acquisition step is based on the required measurement time point, according to the laser sensor data of the measurement point and the vehicle position and inertia data, and the preset model is used to calculate the vertical ground clearance of the measurement point. The preset model is:

[0037]

[0038] Where θ is the angle between the two light beams, a and b are the measurement values ​​of the two laser sensors, and Z is the height above the ground measured in real time.

[0039] The calculation method of the right front wheel arch height from the ground is shown as an example. The specific calculation is as follows:

[0040]

[0041] LFR is the wheel arch height of the vehicle at a certain moment, right front 1 is the measurement value of right front wheel sensor 1 at that moment, right front 2 is the measurement value of right front wheel sensor 2 at that moment, and θ is the fixed angle between the two sensors when they are initially installed.

[0042] The above is only an embodiment of the present invention, and the common knowledge such as the specific technical solutions and / or characteristics in the solution are not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the description can be used to interpret the content of the claims.

Claims

1. A method for dynamically measuring the wheel arch and chassis height of a vehicle, characterized in that: include: Equipment installation steps: install the laser ranging sensor assembly to the preset position of the vehicle measurement point and adjust the position of the laser ranging sensor assembly; Measurement points include vehicle fenders and chassis; The laser distance sensor assembly includes two laser distance sensors, and the rays of the two laser distance sensors form a fixed and known angle in the projection plane; The laser ranging sensor assembly is horizontal along the direction of the vehicle body, the intersection point of the projections of the laser beams of the two laser ranging sensors in the laser ranging sensor assembly in the plane coincides with the projections of the emission points of the laser beams of the two laser ranging sensors in the plane, and the starting position of the laser beam coincides with the measurement point; Data collection step: real-time synchronous triggering to collect laser ranging sensor data and vehicle position and inertia data; A measurement time point acquisition step, obtaining the required measurement time point in real time based on the inertia data; The required measurement time point is the moment when the vehicle reaches the collision point; A step of obtaining the ground clearance, based on the desired measurement time point, according to the laser sensor data of the measurement point and the vehicle position and inertia data, and calculating the vertical ground clearance of the measurement point based on a preset model; The preset model is: Where θ is the angle between the two light beams, a and b are the measurement values ​​of the two laser ranging sensors, and z is the height above the ground measured in real time.

2. The method for dynamically measuring the height of a vehicle's wheel arch and chassis according to claim 1, characterized in that: The angle range is from 0° to 90°.

3. The method for dynamically measuring the height of a vehicle's wheel arch and chassis according to claim 1, wherein: In the measurement time point acquisition step, imc FAMOS Professional processing software is used to use the pos function to find the required measurement time point in real time, and the value function is used to analyze the value of each channel at that time.

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