PARAMETRIC SYNTHESIS OF THE INVARIANT SYSTEM OF CAR COURSE STABILITY

Abstract

The problem of constructing the invariant stabilizer of the ESP (Electronic Stability Program) car course stability system is considered by implementing two control principles by the electronic brake force distribution unit EBD (Electronic Brakeforce Distribution) – the principle of control by deviation and the principle of control by external disturbance. The values of the variable parameters of the stabilization algorithm are selected from the conditions for minimizing both the static and dynamic errors of the system. Two brake fluid pressure sensors are introduced into the EBD structural-functional scheme in the brake lines of the right and left sides of the car. It is proven that the pressure difference of the brake fluid, which is measured by pressure sensors, is proportional to the external disturbance acting on the car body from the side of the road surface. Therefore, in order to give the ESP system the property of invariance to external disturbances, the control signal generated by the EBD electronic unit contains current information not only about the parameters of the disturbed movement of the car, namely, about the angle of deviation of the longitudinal axis of the car relative to the given direction of movement, about the angular velocity of rotation of the body relative to its vertical axis and about lateral displacement of the center of mass of the body, but also the current information about the external disturbance acting on the car body. Recommendations for choosing the values of variable parameters of the ESP system stabilizer are given, which ensure the minimization of both static and dynamic errors of the closed system in the emergency braking mode.