Dynamic estimation method of longitudinal acceleration of automatic mechanical transmission vehicle

Abstract

The invention provides a dynamic estimation method of longitudinal acceleration of an automatic mechanical transmission vehicle. The method includes the steps that firstly, according to power parameter matching of the vehicle, an acceleration threshold limit value is calculated; secondly, whether the vehicle speed V<n-1> at the (n-1)th moment and the vehicle speed V<n-2> at the (n-2)th moment meet the condition that |V<n-1>-V<n-2>| is larger than or equal to 1 or not is judged, if the vehicle speed V<n-1> at the (n-1)th moment and the vehicle speed V<n-2> at the (n-2)th moment meet the condition, the third step is performed, and if the vehicle speed V<n-1> at the (n-1)th moment and the vehicle speed V<n-2> at the (n-2)th moment do not meet the condition, the fourth step is executed; thirdly, after the vehicle speed at the nth moment is filtered, the longitudinal acceleration value a<n> of the vehicle at the current moment is obtained; and fourthly, whether the vehicle speed V<n> at the nth moment and the vehicle speed V<n-1> at the (n-1)th moment meet the condition that |V<n>-V<n-1>| is smaller than or equal to 1 or not is judged, if the vehicle speed V<n> at the nth moment and the vehicle speed V<n-1> at the (n-1)th moment meet the condition, the differential step length is zero and the longitudinal acceleration value a<n> is obtained, and if the vehicle speed V<n> at the nth moment and the vehicle speed V<n-1> at the (n-1)th moment do not meet the condition, an acceleration value at the previous moment is used for replacing the longitudinal acceleration of the vehicle at the current moment. The dynamic estimation method of the longitudinal acceleration of the automatic mechanical transmission vehicle is small in calculation amount, has self-adaptive capacity and can effectively and accurately track the longitudinal acceleration actual value of the vehicle.

Description

technical field [0001] The invention relates to a method for dynamically estimating acceleration, in particular to a method for dynamically estimating longitudinal acceleration of an automatic mechanical transmission vehicle. Background technique [0002] With the rapid development of the automobile industry, AMT has become an important direction of automatic transmission research in my country, especially in the automation transformation process of domestic heavy-duty truck manual transmission, it plays a pivotal role and has a good market application prospect. [0003] The automatic mechanical transmission is based on the traditional fixed-shaft transmission and clutch, applies electronic technology and automatic transmission theory, takes the electronic control unit (TCU) as the core, and controls the separation and engagement of the clutch, the selection and shifting operation and the engine through the execution system. Accelerator adjustment to realize the automatic co...

AI Technical Summary

Problems solved by technology

In the design of AMT system, if the method of directly measuring the acceleration sensor is used, there are the following problems: 1. The cost of the AMT system increases, 2. The life of the acceleration sensor is short in bad road conditions, so the method based on the differentiation of the rotational speed signal is usually used to estimate the longitudinal acceleration of the vehicle

However, due to measurement noise or interference, the differential may cause distortion of the longitudinal acceleration value, which seriously affects the performance of the AMT control strategy

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