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For high torque permanent magnet wheel motor, this paper describes an experimental research method to optimize and identify the motor parameters based on the results of offline calculation. In order to improve the accuracy of motor parameters identification, the motor model considering the affect of iron loss was established, and the motor parameters were identified using genetic algorithm (GA). Based on this, parameters validation experiment was performed. The results show that: parameters obtained by this method can be used to describe the steady-state and transient-state response of permanent magnet synchronous motors accurately.

Vehicle detection has been a fundamental problem in the research of Intelligent Traffic System (ITS), especially in urban driving environment. Over the past decades, vision-based vehicle detection has got a considerable attention. In addition to the rich appearance information, the stereo vision method also provides depth information, which could achieve higher accuracy and precision. In this paper, a hybrid method for stereo vision-based real-time vehicle detection in urban environment is proposed. Firstly, we extract vehicle features and generate the Region of Interest (ROI). Semi-global Matching (SGM) algorithm is then utilized on the ROIs to generate disparity maps and get the depth information, which could be used to compute the width of each ROI. The noise regions, always with obvious depth variation in the disparity maps are excluded by the clustering approach.

Impact torque will be generated on the steering wheel when one tire suddenly blows out on high way, which may cause driver's psychological stress and result in driver's certain misoperations on the car. In this paper, the model of tire blowout vehicle was established; the tire blowout was detected based on the change rate of tire pressure, meanwhile, the rack force caused by tire blowout was estimated through a reduce observer; finally the compensation current was figured out to reduce the impact torque on the steering wheel. Results of simulation tests showed that the control strategy proposed in this paper can effectively reduce the impact torque on the steering wheel and reduce the driver's discomfort caused by tire blowout.

The quality of the brake system is a significant safety factor in commercial vehicles on the roads. With the development of automobile technology, the single function ABS system didn't meet active safety requirements of the user. The Electronically Controlled Brake System (EBS) system will replace the ABS system to become the standard safety equipment of commercial vehicles in the near future. EBS can be said an enhanced ABS system, it contains load sensor, brake valve sensor and pressure sensor of chamber, etc, and it is more advantages than ABS. This paper describes a flexible integrated test bench for ABS/EBS Electronic Control Unit (ECU) based on Hardware-In-the-Loop (HIL) simulation technique. It consists of most commercial vehicle pneumatic braking system components (from brake pedal valve, brake caliper to brake chambers), and uses the dSPACE real-time simulation system to communicate to the hardware I/O interface.

In order to improve the braking energy recovery, a parallel hybrid electric bus simulation model with electric braking system (EBS) was established by co-simulation platform for the TruckSim and Matlab/Simulink in this paper. EBS makes the front and rear shaft braking force arbitrarily distributed, which is more effective to improve the rate of energy recovery and the braking stability. A braking force distribution algorithm for hybrid electric bus based on EBS was designed in this paper. Under the premise to meet the driver's needs and the ECE regulations, this braking force distribution method focuses on making the braking force distribute to the drive shaft to a maximum extent, so as to obtain the maximum energy recovery rate by the utilization of the motor regenerative braking. At last, the simulation in different operating conditions was used to analyze the braking energy utilization and the braking performance based on the simulation model.

Steering-By-Wire (SBW) system has advantages of advanced vehicle control system, which has no mechanical linkage to control the steering wheel and front wheels. It is possible to control the steering wheel actuator and front wheels actuator steering independently. The goal of this paper is to use a joystick to substitute the conventional steering wheel with typical vehicle SBW system and to study a variable steering ratio design method. A 2-DOF vehicle dynamic reference model is built and focused on the vehicle steering performance of drivers control joystick. By verifying the results with a hardware-in-the-loop simulation test bench, it shows this proposed strategy can improve vehicle maneuverability and comfort.

In order to improve the braking energy recovery and ensure the braking comfort, a new type of regenerative braking coordinated control algorithm is designed in this paper. The hierarchical control theory is used to the regenerative braking control algorithm. First, the front axle braking force and rear axle braking force are distributed. Then the rear axle motor braking force and mechanical braking force are distributed. Finally, the dynamic coordinated control strategy is designed to control pneumatic braking system and motor braking system. Aimed at keeping the fluctuation of the total braking force of friction and the regenerative braking force small during braking modes switch, a coordinated controller was designed to control the pneumatic braking system to compensate the error of the motor braking force. Based on Matlab/Simulink platform, a parallel hybrid electric bus simulation model with electric braking system (EBS) was established.

Steering-by-wire(SBW) system makes the vehicle not constrained by the steering wheel control. Joystick, button and touch screen can all be used for automobile steering control. Using joystick to achieve steering operations has its unique advantages and many problems which are needed to be resolved at the same time. This paper firstly introduced the components of traditional steering wheel steer-by-wire system, then came up with the difference between joystick steer-by-wire system and traditional steer-by-wire system about transmission ratio, transmission ratio control strategy of joystick steer-by-wire system is proposed at the same time. At last, this paper studied driver’s busy degree when the vehicle running with a big turning radius at low speed and the effect of different angle transmission ratio on vehicle handing stability when the vehicle running at intermediate speed.

Pressure following control is the basic function of Electro-Hydraulic Braking system (EHB), which is also the key technology of stability control system and regenerative braking system for hybrid and electric vehicles. Experimental research is an important method for the control and application of EHB. This paper describes a method to test and control the EHB system through experiment on the Hardware-in-the-loop (HIL) test bench and wheel motor electric vehicle. First, the HIL test bench was established, in which the EHB was tested, including the characteristics of solenoid valves and motor. Then the wheel cylinder pressure was controlled to follow the specific signal input and the master cylinder pressure. Based on this, EHB and the pressure following control method were applied to the wheel motor electric vehicle. The results show that the braking pressure can follow the driver's braking intention to realize the conventional braking function of electric vehicles.

Four-wheel-drive electric vehicles (4WD Evs) utilize in-wheel electric motors and Electro-Hydraulic Braking system (EHB). Then, all wheels torque can be controlled independently, and the braking pressure can be controlled more accurately and more fast than conventional braking system. Because of these advantages, 4WD Evs have potential applications in control engineering. In this paper, the in-wheel electric motors and EHB are applied as actuators in the vehicle stability control system. Based on the Direct Yaw-moment Control (DYC), the optimized wheel force distribution is given, and the coordination control of the hydraulic braking and the motor braking torque is considered. Then the EHB hardware-in-the-loop test bench is established in order to verify the effectiveness of the vehicle stability control algorithm through experiments.