A common heavy vehicle, such as a bus, has a drum brake system as its safety feature. This braking system utilizes air pressure inside pneumatic cylinders as an actuator for moving the braking cam in order to create friction between the brake shoe with the drum. Air pressure is produced by a compressor with the help of the internal combustion engine (ICE) rotational part. However, in the case of electric vehicles (EV), there is no rotational moving part on the engine when the vehicle stops. Furthermore, EVs use electric power as their fuel obtained from the battery. Thus, this study focuses on developing an alternative actuator for EV braking to substitute the air actuator system by the direct electric powered actuator system. By utilizing a magnetic system via a solenoid for moving the lever of the cam, the tests confirm that the implementation of the alternative actuator functionally works. The objective of this research is to obtain the proper control system in order to gradually generate the magnetic field. Additionally, the signal from the operator is then processed by an intelligent method—so-called fuzzy control—to produce a signal for the magnetic braking system comparable to the behavior of the pneumatic actuator. The results show that the intensity of braking can be alternated depending on the braking signal variation using 10 µs sampling period input pulse width modulation (PWMs) with 10 ms periods of execution time. Furthermore, this method improves the time response that compensates the delay due to piping-hoses in the pneumatic system.
- Electric actuator
- Electric vehicles