The Research Of ABS Logical Threshold Control Algorithm Based On Co-simulation

The anti-lock braking system(ABS)as an efficiency and active safety device,it has progressive realized electronic and integration after developed and improved in pasted half a century.The research of new control theory has diversified the control methods.The most widely used and reliable method is the control algorithm of logical threshold which based on angular acceleration or deceleration and slip ratio.But the value of the threshold just acquired by vehicle road test,because of diversity of vehicle and road,the values can't be used between each other,so it takes a long time on test.The co-simulation of dynamics model and control model provide some helpful method in certain degree and reduced test workload,however the number of braking adjustable,influenced by step of simulation in traditional cosimulation,was too frequently.In view of the above problems,the article analyze attribute of every components of ABS,modify model in disk brake,then build the whole vehicle dynamic models of car,and the model of logical threshold based on wheel angular acceleration or deceleration and slip ratio.At present stage the effective times of braking pressure adjustor is less than twenty per second,by contrast of hundred times in traditional simulation,and then in this paper discrete sampling on control instruction that sent out by ECU.Simulate actual brake situation by keeping the number of adjustable less than twenty.The model is simulated on two different roads,the high adhesion road and the low adhesion road,and take braking distance,wheel speed and slid ratio as evaluated index,acquire the values of wheel angular acceleration or deceleration and slip ratio by the method of variable control,and realize effect in prescribe number of adjustable,achieve corresponding threshold.Contrast with conventional braking system,as it turned out,indicators are obviously improved,the model based on number of adjustable could achieve the goal of simulation.