The Design Of Truck’s ABS Controller Is Based On Composite Logic Threshold Control Method

The safety of drivers and the other vehicles is threatened under thecondition of instability, which is caused by high load and large inertia oftruck in the process of braking. ABS (Anti-lock Braking System) is usedmore and more widely, which could improve the braking stability, themaneuverability and braking distance. In this paper, aimed at theseproblems in ABS controller of truck, the control algorithm andimplementation of ABS are studied emphatically.According to the problems in the traditional ABS controller, whichincluding complex control logic, the lack of contact between thresholdvalues and being disturbed easily, the hard matching of vehicle type andso on. The traditional logic threshold control method is transformed intocomposite logic threshold control method by the analysis of each logicthreshold value of braking effect, which using a large number ofexperimental data. The method adopts a composite logic thresholdparameter to reflect the trend of the wheel locking, which using brakingpressure regulation as the basis. In addition, wheel speeds calculationmethod, reference speed calculation method and the compensationmethod are researched and improved in this method.Aiming at the high cost of controller of ABS, and the low accuracyand reliability, the ABS controller is designed. Fault protection moduleis designed to guarantee the conventional braking capacity under anyfailure. Composite logic threshold control algorithm is realized. Fixedprogram cycle average method is used to calculate the wheel speeds,which is convenient to filter. The slope is adjustable to count referencespeed. The steering compensation is adopted to avoid the influence inthe control parameters which are caused by different speeds on bothsides.For the purpose of inspecting the algorithm feasibility and systemstability, the original ABS controller and self-developed ABS controllerare used on the real road test. The results show that the brakingpercentage of self-developed ABS is above75%, the braking distanceand deceleration are also prior to the original one. At the same time, the truck model is matched and the cost is reduced. The research in thispaper is meaningful in theory of ABS and industrial applications.