Estimation of tire-road peak adhesion coefficient for intelligent electric vehicles based on camera and tire dynamics information fusion

The power battery state of charge (SOC) in electric vehicles is not easy to measure accurately or apply a sensor but the expense is increased. However the variable of SOC is great importance to control of electric vehicles. A power battery model is built by the Partnership for a New Generation of Vehicles (PNGV) model to estimate the state of SOC. In order to make a high accurate estimate for SOC value, an information fusion algorithm based on unscented kalman filter (UKF) is introduced to design an observer. The test results show that the observer based information fusion and UKF are effective and accuracy, so it is may apply it the electric vehicle control and observation.

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Research on Road Adhesion Coefficient Estimation for Electric Vehicle under Tire Cornering Condition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.427-429.275 ◽

2013 ◽

Vol 427-429 ◽

pp. 275-279

Author(s):

Yi Chen ◽

Xue Feng Li ◽

Tong Qu

Keyword(s):

Electric Vehicle ◽

Electric Vehicles ◽

Estimation Method ◽

Stability Control ◽

Adhesion Coefficient ◽

Estimation Algorithms ◽

Coefficient Estimation ◽

Stability Control System ◽

Longitudinal Slip ◽

Dynamics Stability

The research came up with a road adhesion coefficient estimation method for electric vehicle under tire cornering condition, compared with the previous researches that mainly focused on tire longitudinal behaviors. The designed identification method first distinguishes the states of small longitudinal slip and large longitudinal slip in the condition of tire cornering. Then estimation algorithms for the two conditions above operate respectively. By designing the simulation and selecting typical road conditions, the applicability and validity of the algorithm have been verified. The estimation method can be used to serve the electric vehicles dynamics stability control system.

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Study on the Rollover Characteristic of In-Wheel-Motor-Driven Electric Vehicles Considering Road and Electromagnetic Excitation

Shock and Vibration ◽

10.1155/2016/2450573 ◽

2016 ◽

Vol 2016 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Di Tan ◽

Haitao Wang ◽

Qiang Wang

Keyword(s):

Electric Vehicles ◽

Electromagnetic Force ◽

Load Transfer ◽

Influential Factor ◽

Vehicle Speed ◽

Electromagnetic Excitation ◽

Adhesion Coefficient ◽

The Road ◽

Vehicle Rollover ◽

Rollover Stability

For in-wheel-motor-driven electric vehicles, the motor is installed in the wheel directly. Tyre runout and uneven load can cause magnet gap deformation in the motor, which will produce electromagnetic forces that further influence the vehicle rollover characteristics. To study the rollover characteristics, a verified 16-degree-of-freedom rollover dynamic model is introduced. Next, the vehicle rollover characteristics both with and without electromagnetic force are analyzed under conditions of the Fixed Timing Fishhook steering and grade B road excitation. The results show that the electromagnetic force has a certain effect on the load transfer and can reduce the antirollover performance of the vehicle. Therefore, the effect of the electromagnetic force on the rollover characteristic should be considered in the vehicle design. To this end, extensive analysis was conducted on the effect of the road level, vehicle speed, and the road adhesion coefficient on the vehicle rollover stability. The results indicate that vehicle rollover stability worsens when the above-mentioned factors increase, the most influential factor being the road adhesion coefficient followed by vehicle speed and road level. This paper can offer certain theory basis for the design of the in-wheel-motor-driven electric vehicles.

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Study on Adaptive Slid Mode Controller for Improving Handling Stability of Motorized Electric Vehicles

Mathematical Problems in Engineering ◽

10.1155/2014/240857 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

LiQiang Jin ◽

Yue Liu

Keyword(s):

Real Time ◽

Electric Vehicle ◽

Working Conditions ◽

Electric Vehicles ◽

Control Method ◽

Slip Angle ◽

Adhesion Coefficient ◽

Side Slip Angle ◽

The Real ◽

The One

An adaptive slid mode controller was established for improving the handling stability of motorized electric vehicle (MEV). First and foremost, the structure and advantages of electric vehicle driven by in-wheel motors will be provided. Then, an ideal cornering model of vehicles will be brought and analyzed, after which a method to estimate side-slip angle was also proposed and three typical sensors were used in the theory. Besides, an idea for the recognition of road adhesion coefficient was derived based on MEV platform, which will be helpful for better control performances. Finally, the scheme of control method was given and some typical tests for observing handling properties were implemented based on Simulink and Carsim software. With the outcomes from the experiments, which vividly showed the merits of the controller, one can come to a conclusion that MEV that equips with the adaptive slid mode controller always enjoys better handling performances than the one without control. Furthermore, the controller researched is friendly to the real-time working conditions, which will hold practical values in the future.

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