Design of a fault tolerant redundant control for electro mechanical drive system

This paper deals with a design of a electromechanical actuator (EMA) control system with advanced safety requirements. Based on the Failure Mode and Effects Analysis (FMEA), a redundant structure of sensors and electronic control units (ECUs) is proposed. Following the compromise between safety and simplicity, only two channels (sensors and ECUs) are used. A Voter (hardware which routes the output signals from ECUs to power electronics) is implemented on a complex programmable logic device (CPLD) using hardware description language (HDL). As a case study, the proposed system structure is implemented on a self-balancing vehicle control system. The Model Based Design (MBD) approach is applied during the system development and testing. ECUs are based on dsPIC Microchip devices and programmed using automatically generated C code.