Modeling of a Speed Control System Using Event-B

The present paper presents our proposal of an Event-B model of a speed control system, a part of the case study provided in the ABZ2020 conference. The case study describes how the system regulates the current speed of a car according to a set criteria like the speed desired by the driver, the position of a possible preceding vehicle but also a given speed limit that the driver must not exceed. For that purpose, this controller reads different information form the available sensors (key state, desired speed, etc.) and takes the adequate actions by acting on the actuators of the car’s speed according to the read information. To formally model this system, we adopt a stepwise refinement approach with the Event-B method. We consider most features of the case study, all proof obligations have been discharged using the Rodin provers. Our model has been validated using ProB by applying the different provided scenarios. This validation has permitted us to point out and correct some mistakes, ambiguities and oversights contained in the first versions of the case study.