Task-based Dynamic Fault Tolerance for Humanoid Robots

Although the performance of humanoid robots is rapidly improving, very few dependability schemes suitable for humanoid robots have been presented thus far. In particular, the fault tolerance of the engine (i.e., CPU module) has not been discussed. In the future, various tasks ranging from daily chores to safety-related tasks will be carried out by individual humanoid robots. If the characteristics and importance of the given tasks are different, the required fault-tolerant capabilities will also vary accordingly. Therefore, for mobile humanoid robots operating under power constraints, a dynamic fault tolerance capable of reducing the power consumption is desirable because fault-tolerant designs involving hardware redundancy are power intensive. In addition, an appropriate safety operation must be determined for each task. This paper discusses the dependability of humanoid robots and proposes a task-based dynamic fault tolerance scheme as a vital concept for humanoid robot applications; this scheme is based on hardware redundancy of the engine.