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A tire force estimation algorithm is proposed for vehicle dynamic stability control (DSC) system to protect the vehicle from deviation of the normal dynamics attitude and to realize the improved dynamics stability in limited driving conditions. The developed algorithm is based on the theoretical analysis of all the subsystems of the active brake control in DSC system and modulation in DSC, and the robustness is achieved by a compensation method using nonlinear filter in the real time control. The software-in-loop simulation using Matlab/AMEsim and the ground test in the real car show the validation of this method.

Many types of brake by wire systems have been developed in past years, such as EMB (Electro-mechanical Brake) [1, 2], DEHB (Distributed Electro-hydraulic Braking System) [3] and EWB (Electric Wedge Brake) [4]. When the vehicle need braking in long period such as waiting for traffic light or downhill braking in those brake systems, the current will sustain very long time with very high level. This current will result in high temperature in motor, and will damage the power supplier. When a new DEHB is developing, a holding function is added in this DEHB. The holding function is self-energized when holding the brake, and automatic released after the brake. Advantageously, after activation of the holding function, the current delivered to the motor for braking is substantially decreased, especially, will be zero when the brake torque is not need to adjust.

This paper presents a new magnetorheological braking which can be used in vehicles. Magneto-rheological (MR) fluid is a novel material which can be used in different components of vehicle. Magneto-rheological fluids (MRF) are suspensions of micron size whose yield stress varies rapidly as the change of magnetic field. The use of MRF in vehicles has been gaining popular recently due to its strong rheological effect, fast response and low energy consumption. Besides, these performances give designers more choice in automotive designs. However, most of the related research of MRF brake is about the construction of small prototype to verify its rheological performance. As a result, research progress is limited to calculation and simulation which make the braking force of prototype can hardly meet the requirement of vehicle due to a lack of optimal design and the understanding of MRF in the situation of high sheer stress and magnetic field.

Special purpose flat-bed vehicle is commonly utilized to move heavily items such as containers in warehouse, port and other freight handling scene, the hydraulic steering system have be gradually replaced by electric ones. However, the cost of electric steering system is high for commercial activities. Thus, for some corporates, the differential braking steering strategy becomes an ideal alternative. The purpose of this paper is to present a steering control method for flat-bed electric vehicle based on differential braking system. There are two main components of the control method, steering while moving forward and pivot steering, and each of them was composed by upper layer and executive layer. To evaluate the practicability of the control methods, a 7-DOF flat-bed vehicle model was established in Simulink.