HIC: an operating system for hierarchies of servo loops

A description is given of HIC (hierarchical control system), an operating system specifically for hierarchies of servo loops often found in robot controllers. It uses the simple nature of servos (as processes) to its advantage. Key features of HIC are a simple and efficient scheduler for servos and asynchronous events and a (nominally) nonblocking message-passing structure, the periodic data buffer. The system is implemented and running in the NYU controller for the Utah/MIT hand.<
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