Method for dynamically measuring heights of wheel trim and chassis of vehicle

Abstract

The invention relates to the technical field of automobile testing, and discloses a method for dynamically measuring the height of a wheel trim and a chassis of a vehicle, which comprises the following steps: an equipment mounting step: mounting a laser distance measuring sensor assembly at a preset position of a vehicle measuring point, and adjusting the pose of the laser distance measuring sensor assembly; a data acquisition step of synchronously triggering acquisition of laser distance measuring sensor data and vehicle position and inertia data in real time; in the measurement time point acquisition step, a required measurement time point is acquired in real time based on inertia data; in the step of obtaining the ground clearance, the vertical ground clearance of a measurement point is calculated based on a preset model according to the data of the laser sensor of the measurement point and the vehicle position and inertia data on the basis of a required measurement time point. The vehicle wheel trim and chassis terrain clearance can be dynamically measured in real time, the measurement precision is higher, and equipment assembly is more convenient.

Description

Technical Field

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

[0002] With the rapid development of intelligent transportation systems and autonomous driving technology, vehicles are becoming increasingly safer, more comfortable and more intelligent. In these advanced transportation systems, it is particularly important to accurately measure key vehicle parameters (such as wheel arches and chassis height). Although traditional static measurement methods can provide relatively accurate measurement results when the vehicle is stationary, during the vehicle's driving process, static measurement cannot reflect the vehicle's true state in real time due to factors such as dynamic changes in the suspension system, body ups and downs caused by uneven road surfaces, and changes in vehicle speed. Therefore, real-time dynamic measurement of vehicle wheel arches and chassis ground clearance has important 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 wheel arch and chassis, so as to dynamically measure the height of the vehicle 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 scheme:

[0005] A method for dynamically measuring the height of a wheel arch and a chassis 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 laser ranging sensor assembly posture;

[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 step of obtaining the ground clearance 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 vertical ground clearance of the measurement point is calculated based on a preset model.

[0010] The principle and advantage 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 prior art 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, but the vehicle's moving center of mass 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, and the accuracy of the inertial navigation acquisition angle is not high, which will also cause 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 at the same time, and the data at the same time is recorded in real time to ensure that the vehicle wheel arch height measurement value is consistent with the inertial navigation measurement parameter, 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] Among them, 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 off the ground and reduce the angle error caused by pitch.

[0017] Preferably, as an improvement, the angle range is from 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 two laser ranging sensor laser beams 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 A 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 obtaining codes for measuring time points required in 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 comprises:

[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 to the measurement point positions of the four wheel arches and chassis, such as Figure 2 As shown, the wheel arch contains a total of four laser ranging sensor assemblies (eight laser ranging sensors), and the chassis contains a group of laser ranging sensor assemblies (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, and the rays of the two laser ranging sensors form a fixed and known angle in the projection plane, with an angle range of 0° to 90°, to ensure that the light beam of the laser sensor hits the ground.

[0032] During installation, the laser distance sensor assembly is horizontal along the vehicle body direction, the intersection of the projection of the laser beams of the two laser distance sensors in the laser distance sensor assembly in the plane coincides with the projection of the emission points of the laser beams of the two laser distance sensors in the plane, and the starting position of the laser beam coincides with the measurement point. In this solution, as long as the two laser distance sensors are within the sensor range, there is no need to consider the horizontality around the Y direction, which is one less direction to consider than the existing solution.

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

[0034] Specifically, the inertial navigation system is arranged at the rear of the center channel 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 angle and roll angle measured by the inertial navigation system with 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, 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 step of obtaining the ground clearance is to calculate the vertical ground clearance of the measuring point based on the required measurement time point, according to the laser sensor data of the measuring point and the vehicle position and inertia data, based on the preset model. The preset model is:

[0037]

[0038] Among them, 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] Take the calculation method of the right front wheel fender height from the ground as an example, the specific calculation is as follows:

[0040]

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

[0042] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is 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 modifications and improvements can be made, which should also be regarded as the protection scope 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 specification can be used to interpret the content of the claims.

Claims

1. A method for dynamically measuring the height of a vehicle wheel arch and chassis, 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 laser ranging sensor assembly posture; 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 step of obtaining the ground clearance 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 vertical ground clearance of the measurement point is calculated based on a preset model.

2. The method for dynamically measuring the height of a vehicle wheel arch and chassis according to claim 1, characterized in that: The preset model is: Among them, 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.

3. The method for dynamically measuring the height of a vehicle wheel arch and chassis according to claim 1, characterized in that: The laser distance measuring sensor assembly includes two laser distance measuring sensors, and the rays of the two laser distance measuring sensors form a fixed and known angle in the projection plane.

4. The method for dynamically measuring the height of a vehicle wheel arch and chassis according to claim 3, characterized in that: The angle ranges from 0° to 90°.

5. The method for dynamically measuring the height of a vehicle wheel arch and chassis according to claim 1, characterized in that: 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.

6. The method for dynamically measuring the height of a vehicle wheel arch and chassis according to claim 1, characterized in that: The required measurement time point is the time when the vehicle reaches the collision point.

7. The method for dynamically measuring the height of a vehicle wheel arch and chassis according to claim 1, characterized in that: 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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