CN111186482A

CN111186482A - EPS data security acquisition method based on three-system TAS

Info

Publication number: CN111186482A
Application number: CN202010076752.1A
Authority: CN
Inventors: 李明; 何文彪; 戴立伟; 张永生; 向坤; 王静
Original assignee: China Highway Vehicle and Machinery Co Ltd
Current assignee: China Highway Vehicle and Machinery Co Ltd
Priority date: 2020-01-23
Filing date: 2020-01-23
Publication date: 2020-05-22

Abstract

The invention discloses a safety obtaining method of EPS data based on a three-system TAS, which comprises the steps that an ECU of an electric steering power-assisted system collects corner data and torque data of a steering wheel through a plurality of corner torque modules; detecting the fault state of each corner torque module; and averaging the data collected by the corner torque module without faults and using the averaged data as the corner and torque input parameters of the ECU steering wheel. According to the invention, the accuracy of data acquisition of the EPS is realized through the data detection module arranged in a redundant manner, so that the accuracy of assistance provided by the EPS is realized, and the assistance abnormity caused by the fault of steering wheel corner torque data is avoided, and the normal and safe running of a vehicle is influenced; meanwhile, the average value data of the normal corner torque module is used as the input control parameter for providing the assistance by the EPS, so that the assistance can be more accurate and scientific.

Description

EPS data security acquisition method based on three-system TAS

Technical Field

The invention relates to the technical field of EPS (electric power steering) power-assisted steering, in particular to a method for accurately acquiring direction parameters by an EPS (electric power steering).

Background

The EPS is called an electric power steering system for providing electric power for steering operation of a steering wheel, so that the steering wheel is more labor-saving and easier in the rotating process. In the prior art, if the steering angle sensing module fails to provide accurate data, the ECU of the EPS cannot provide the steering assistance through accurate torque and angle data, and the operation of the whole EPS is affected.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, provides an EPS safety design method based on a three-system TAS, and aims to realize redundancy and error prevention by arranging a plurality of groups of corner torque modules so as to improve the safety and stability of the operation of an EPS system, thereby realizing the safe acquisition of data and ensuring the safe operation of the EPS.

In order to achieve the purpose, the invention adopts the technical scheme that: an EPS data security acquisition method based on three-system TAS comprises the following steps,

an ECU of the electric power steering system collects corner data and torque data of a steering wheel through a plurality of corner torque modules;

detecting the fault state of each corner torque module;

and averaging the data collected by the corner torque module without faults and using the averaged data as the corner and torque input parameters of the ECU steering wheel.

If all the corner torque modules are in a fault state, the ECU acquires preset safe steering wheel parameters, and the safe steering wheel parameters are used for providing steering assistance.

The fault detection of the corner torque module comprises module self-checking and/or ECU data analysis and detection, and the fault state is detected through chip self-checking and/or is analyzed through data transmitted by the ECU analysis module.

And the ECU analyzes whether the fault comprises the data transmitted by frequency and pulse width analysis and whether the data is abnormal.

The self-check of the corner torque module comprises power supply diagnosis, grounding diagnosis and/or program self-check. The number of the corner torque modules is preferably 3.

The invention has the advantages that: the accuracy of data acquisition of the EPS is realized through the data detection module arranged in a redundant manner, so that the accuracy of assistance provided by the EPS is realized, and the assistance abnormity caused by the fault of the steering wheel corner torque data is avoided, and the normal and safe running of a vehicle is influenced; meanwhile, the mean value data of the normal corner torque module is used as the input control parameters for providing the assistance by the EPS, so that the assistance can be more accurate and scientific, and when all the components are in failure, the preset safe corner and torque values can be used as the input parameters for the assistance by the ECU, so that certain assistance can be still provided normally when the sensor is in failure.

Drawings

The contents of the expressions in the various figures of the present specification and the labels in the figures are briefly described as follows:

FIG. 1 is a schematic view of the EPS steering wheel data acquisition of the present invention;

fig. 2 is a schematic diagram of an ECU data acquisition process of the EPS of the present invention.

Detailed Description

The following description of preferred embodiments of the invention will be made in further detail with reference to the accompanying drawings.

In the prior art, an ECU of an EPS electric power steering system provides data assurance for the operation of an EPS by detecting relevant parameters of a steering wheel, such as the magnitude of assistance provided by collecting the turning angle and the torque of the steering wheel. In the prior art, a pair of detection modules are modularized to detect corresponding rotation angle and torque, wherein the detection modules comprise a rotation angle sensor and a torque sensor, and are conventionally used as an integrated chip to respectively output the rotation angle and the torque through two paths of outputs. Then make the ECU of EPS unable normal work when this chip module breaks down, that is to say can't realize electronic helping hand, cause electronic helping hand trouble, for this application of solving this problem provides a plurality of detection modules and is used for data acquisition, then through whether each module breaks down and regards as the detected value with the mean value of the detection module detection that does not break down, provides input data for ECU's steering helping hand. The method comprises the following specific steps:

the EPS safety design method based on the three-system TAS comprises the steps that an ECU of the electric steering power-assisted system collects steering angle data and torque data of a steering wheel through a plurality of steering angle torque modules; the corner torque module is generally an integrated chip, called as a torque corner sensor TAS, and takes three torque corner sensors as an example, and output data of the three torque corner sensors are respectively sent to an ECU of the EPS; a failure state of each torque angle sensor is detected.

When all the three sensors are detected to be in failure, the ECU takes the pre-stored safe and reliable torque angle data as an input parameter for providing the steering assistance, and provides the assistance according to the input parameter. The pre-stored calibrated torque angle data can be set with reasonable data so that the ECU can output mild power assistance, and can be calibrated according to actual requirements so as to realize that the provided power assistance can meet various steering requirements of the vehicle as much as possible.

And when part of faults are detected to be not faulted, averaging data collected by the corner torque module without faults to serve as corner and torque input parameters of the ECU steering wheel.

Taking three torque angle sensors as an example, the three sensors are respectively T1, T2 and T3, when all the three sensors are detected to be normal, the torque output by the T1, the T2 and the T3 is added and divided by three to obtain an average torque value as a torque input value of the ECU, the output angle values of the T1, the T2 and the T3 are added and divided by three to obtain an average angle value as an angle input value of the ECU, and the ECU performs operation control to output the boosting force according to the average torque value and the average angle value.

When all the three sensors T1, T2 and T3 fail, electric power assist is provided by using the pre-stored torque M and the rotation angle w as input parameters for electric power assist control by the ECU so as to satisfy the normal operation of the EPS at the time of failure to provide power assist.

When a T1 fault is detected, the average value of the torque and the average value of the rotation angle detected by T2 and T3 are used as input parameters for providing the steering assistance by the ECU; the same applies to the T2 fault and the T3 fault.

When two of the three sensors fail, only one of the sensors remains to fail, and the data of the sensor that has not failed is used as an input parameter required for the operation of the ECU to control the steering assist. If the faults of T1 and T2 occur, the data of T3 is used as the input parameters of the ECU operation control steering assistance.

The torque rotation angle sensor TAS is an integrated sensor and has a certain self-checking capability, so that fault detection includes self-checking of a sensor chip and/or data analysis and detection of the ECU. The sensor self-checking means that the sensor detects a fault through the sensor after the sensor is electrified, and the sensor self-checking comprises power supply diagnosis, grounding diagnosis and/or program self-checking. After the sensor chip detects the fault, the fault flag bit is output to the ECU, and the ECU can know that the detection data corresponding to the chip is abnormal and the sensor is in fault. The ECU analyzes the fault, namely, whether the data transmitted by frequency and pulse width analysis is abnormal or not is diagnosed by the protocol due to the requirements of interaction protocols and the like existing in data interaction between the ECU and the sensor, and the sensor can be placed in a fault position when the data are abnormal, so that the sensor is considered to be in the fault state.

It is clear that the specific implementation of the invention is not restricted to the above-described embodiments, but that various insubstantial modifications of the inventive process concept and technical solutions are within the scope of protection of the invention.

Claims

1. The EPS data security acquisition method based on the three-system TAS is characterized by comprising the following steps:

detecting the fault state of each corner torque module;

2. The method for safely acquiring EPS data based on the three-system TAS as claimed in claim 1, wherein: if all the corner torque modules are in a fault state, the ECU acquires preset safe steering wheel parameters, and the safe steering wheel parameters are used for providing steering assistance.

3. The method for safely acquiring EPS data based on the three-system TAS as claimed in claim 1, wherein: the fault detection of the corner torque module comprises module self-checking and/or ECU data analysis and detection, and the fault state is detected through chip self-checking and/or is analyzed through data transmitted by the ECU analysis module.

4. The method for safely acquiring EPS data based on the three-system TAS as claimed in claim 3, wherein: and the ECU analyzes whether the fault comprises the data transmitted by frequency and pulse width analysis and whether the data is abnormal.

5. The method for safely acquiring EPS data based on the three-system TAS as claimed in claim 3, wherein: the self-check of the corner torque module comprises power supply diagnosis, grounding diagnosis and/or program self-check.

6. The method for safely acquiring EPS data based on the three-system TAS as claimed in claim 1, wherein: the number of the corner torque modules is three.