A Distributed Message Passing Computational and I/O Engine for Real-Time Motion Control

This paper illustrates the use of the Yale XP/DCS - a dual-board real-time distributed control module based upon the INMOS Transputer family of microprocessors - for high performance real-time motion control applications. The XP/DCS complements the the Transputer's 1.5 Mflop computational rate and four independent on-chip 20 Mbps DMA communication engines, by providing a bidirectional latched 32 bit bus extension with full handshaking support for easy customization of the I/O capabilities of any node. After contrasting this design with commercially available alternatives we describe three particular applications presently underway in the Yale Robotics Laboratory. We conclude by reporting some initial experiments concerning the effect of code distribution and message passing protocols upon sampling rate.