Extended Reliability Analysis of Fault-Tolerant FPGA-based Robot Controller

The reliability of safety-critical systems is very important especially in case of electronic systems which are working in environment with increased occurrence of faults. As an example, space, aerospace or medical systems can serve. Fault tolerance is one of the techniques the goal of which is to avoid the impact of faults on such systems. Lots of fault tolerance techniques exists and new ones are under investigation. This paper is targeted mainly to Field Programmable Gate Arrays (FPGAs) which are also the target technology of many fault tolerant techniques. It is important to evaluate and test these techniques. This paper is the continuation of our previously published research results which presents experimental approach to evaluate such fault tolerance techniques by monitoring the impact of faults in the experimental electro-mechanical system utilizing robot navigation in a maze. However, in this paper, we research and compare similarities of the theoretical estimation to various methods of the SEU injection approaches. The theoretical estimation is calculated using known equations. The impact of artificially faults injected into the electronic controller, in which Triple Modular Redundancy is applied, is monitored and used for statistic reliability analysis. This approach serves as a tool for the fast reliability evaluation during the development process of fault tolerance systems.