Design of FlexRay-based communication on triplex redundancy flight control computer

To further improve the safety and reliability of small unmanned aerial vehicle (UAV), triplex redundancy flight control computer and its strategy of redundancy management were designed. And considering the limitations of communication speed and data communication load of traditional CAN bus, FlexRay-based communication mechanism has been designed. Specifically, mosular hardware has integrated the driver circuits, expanding FLASH and expanding RAM with the core board and its motherboard designed respectively, which is for the system upgrade and can protect the CPU. Then two-level redundancy management ideas of software vote and hardware arbitration were proposed in redundancy management design. Finally FlexRay bus was chosen to form the cross communication data link (CCDL) and to achieve communication mechanism among three channels. The analysis shows that the hardware design is reasonable, and the FlexRay-based CCDL can complete the data sharing of serial quantity, discrete quantity, analogue quantity, PWM quantity and state quantity in the design of 84 time slots with proper length.