Development of DSC (dynamic stability control)

摘要

Mazda has newly introduced Dynamic Stability Control (DSC) in the new CAPELLA, which has also been adopted in the new DEMIO. The DSC is a system that improves safety by means of combining independent brake control at each wheel and engine torque control in order to control skidding of the vehicle. Features of the Mazda DSC are: (1) to focus on quick and large skid, which is beyond driver's correction capability, (2) and to control the skidding of the vehicle within a degree of driver's smooth and easier correction. (3) to ensure sufficient turn-in performance keeping vehicle stability in the case of special driving scenes such as emergency maneuvers. Driver's perceptibility against dangerous condition was also considered. Mazda DSC can control the magnitude of vehicle skid while permitting small skid, regarding the driver as the lead and the DSC as support. Specifically, in addition to the use of the basic control of yaw rate and angular velocity of vehicle slip, the following software schemes were adopted: a) variable intervention timing relating to vehicle's and driver's situation, b) incorporation of driver's operating condition in the control reference to reflect driver's intent in control. A hydraulic unit with quick response was adopted in hardware in order to reduce time delay of the operation. As the result, the system can improve safety regardless of driver's skill with smooth control, while minimizing unintentional control for the driver. In this paper, the development objective of Mazda DSC and its feature are introduced.