Vehicle-mounted road surface longitudinal gradient real-time identification method and device

Abstract

The invention provides a vehicle-mounted road surface longitudinal gradient real-time identification method and device, and belongs to the technical field of vehicles. The existing problem that a gradient value cannot be calculated accurately under all working conditions is solved. The vehicle-mounted road surface longitudinal gradient real-time identification method includes the following steps that a steady-state gradient calculation module looks up a table to obtain a steady-state gradient value according to the difference between a vehicle-mounted longitudinal acceleration signal and actual acceleration; a dynamic gradient calculation module calculates a dynamic gradient value according to a vehicle-mounted longitudinal acceleration signal and the actual acceleration; a gradient correction module corrects the dynamic gradient value calculated by the dynamic calculation module according to the steady-state gradient value calculated by the steady-state gradient calculation module to obtain a corrected gradient value; according to the current working condition information transmitted by a driving condition judging module , a control module judges whether the steady-state gradient value calculated by the steady-state gradient calculation module is adopted or the corrected gradient value corrected by the gradient correction module is adopted. According to the vehicle-mounted road surface longitudinal gradient real-time identification method and device, the accuracy of calculating the gradient value under the full working conditions can be realized.

Description

technical field [0001] The invention belongs to the technical field of automobiles, and relates to a method and a device for real-time identification of the longitudinal slope of a vehicle-mounted road surface. Background technique [0002] Slope is an important parameter of the new energy vehicle vehicle control system and transmission control system. It is used for torque correction of hill start and creep, coasting energy motor feedback torque control and shift line correction of climbing conditions, etc., requiring calculation Small quantity, high accuracy and good real-time performance. [0003] Aiming at the slope problem, patent 201210177067.3 discloses a method for real-time estimation of road surface slope during vehicle driving, comprising the following steps: the vehicle controller controls the driving force sensor, vehicle speed sensor and acceleration sensor to send signals to the slope estimation system respectively; vehicle acceleration The calculation module...

AI Technical Summary

Problems solved by technology

[0003] Aiming at the slope problem, patent 201210177067.3 discloses a method for real-time estimation of road surface slope during vehicle driving, comprising the following steps: the vehicle controller controls the driving force sensor, vehicle speed sensor and acceleration sensor to send signals to the slope estimation system respectively; vehicle acceleration The calculation module calculates the vehicle acceleration and sends it to the slope estimation system; calculates the estimated road slope based on the longitudinal dynamics slope estimation module and sends it to the multi-method fusion slope estimation module; calculates the road slope estimate based on the acceleration deviation slope estimation module value, and send it to the multi-method fusion slope estimation module; the multi-method fusion slope estimation module filters the two estimated road slope values ​​respectively to obtain the real-time estimated value of the road slope; after completing the estimation of the road slope value, repeat the above steps Real-time estimation of the road slope at each sampling moment until the vehicle is turned off. This method is suitable for real-time estimation of the road slope of various vehicles in various working conditions during driving, but the slope of this method cannot be calculated when parking

Patent CN201711032149.8 discloses a slope recognition method based on the acceleration signal, which recognizes the road slope value according to the vehicle speed and acceleration. The real-time performance is good, but the accuracy is not high enough

In summary, the adaptability of the two algorithms to working conditions is not good enough, and it is impossible to accurately calculate the slope value under all working conditions

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