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In this research, we examine the three controls inside-outside wheel braking force and driving force, camber angle, and the derivative steering assistance to determine how angle differences affect cornering performance and controllability. This is accomplished by comparing body slip angle area differences in a closed loop examination of the grip to drift area using a driving simulator. The results show that inside-outside wheel braking force and driving force control in the area just before critical cornering occurs has a significant effect on vehicle stability. We also clarified that controlling the camber angle enhances grip-cornering force, and confirmed that the sideslip limit could be improved in the vicinity of the critical cornering area. Additionally, when the counter steer response was improved by the use of derivative steering assistance control in the drift area exceeding the critical cornering limit, corrective steering became easier.

As for this research, the driver’s risk at the time of cornering was evaluated. As a result, the amount of perspiration became a big difference though the change in the amount of the vehicle state of non-drive skill person and the drive skill person did not have a remarkable difference at the time of the drift cornering. That is, the amount of perspiration when the steer is controlled in case of the drive skill person is small. Therefore, it has been understood that it is a steer control of the risk which is not too large.

In this research, driver risk (subjective feeling of danger) during pylon slalom and drift turning was evaluated by measuring the amount of driver perspiration. The result (the product of the amount of maximum perspiration and the perspiration amount area at the unit running time) is believed to correspond to a subjective rating of the feeling of danger. Moreover, a peculiar phenomenon was observed during drift cornering in which a large degree of fear was experienced if there was a possibility that the vehicle might spin, thus considerably increasing the amount of perspiration. Here, perspiration amount area shows the total amount of perspiration, additional to baseline levels, over a given time frame. And, unit running time shows the same as saying ‘averaged over time’

It has been reported that steering systems with derivative terms have a heightened lateral acceleration and yaw rate response in the normal driving range. However, in ranges where the lateral acceleration is high, the cornering force of the front wheels decreases and hence becomes less effective. Therefore, we applied traction control for the inner and outer wheels based on the steering angle velocity to improve the steering effectiveness at high lateral accelerations. An experiment using a driving simulator showed that the vehicle's yaw rate response improved for a double lane change to avoid a hazard; this improves hazard avoidance performance. Regarding improved vehicle control in the cornering margins, traction control for the inner and outer wheels is being developed further, and much research and development has been reported. However, in the total skid margin, where few margin remains in the forward and reverse drive forces on the tires, spinout is unavoidable.