Design and development of fault tolerant can-lin gateway for in-vehicle communication

In last few decades, the rising numbers of sensors, actuators and ECUs have increased the complexity of automotive network. Moreover, multiple network communication protocols such as CAN, LIN, FlexRay, MOST are used in today's cars to meet the various requirements of in-vehicle applications. While CAN is the traditional automotive field-bus used in engine management, LIN provides a low-cost network solution for car window and door applications. In many instances data has to be shared between various networks using different protocols. Network gateway(GW) enables this data exchange with optimum utilization of the available data/signals. Typically over 25–45 ECUs connected in a vehicle with two to four different network protocols exchange approximately 100–300 signals and data [1], [2]. An error free data transfer from one protocol to another through GW ECU is a challenging and critical task. Failure or error in data exchange can lead to safety problems or inconvenience to the passenger.

GW failure may happen due to failure in software algorithm or hardware. In this paper, a fault tolerant GW proposed to tackle failure in hardware. Design configuration depends on number of controllers, transceivers used, criticality of subsystem and software algorithm implemented. Basic configurations are proposed highlighting the advantages and disadvantages.

Out of five basic configurations proposed, penta configuration fault tolerant CAN-LIN GW design is developed with limited features using PIC18F4580, MCP2551 and TPIC1021 and its feasibility tested under lab environment. Each controller is assumed to support one protocol path. Software control algorithm is developed for CAN-LIN GW. Experimental and simulation results are presented and discussed.