RISC-based architectures for multiple robot systems

Several approaches to multiple robot system control are discussed. In order to simplify the study a multilayered model is proposed: a control layer which directly acts on the dynamics of the manipulators, a coordination/communication layer which makes all the manipulators work together and a programming layer which interfaces with the user. For the first layer two architectural alternatives are studied: a centralized single processor system and a distributed multiprocessor with static task assignment. For the second case an implementation based on the 1960 family of RISC processors is introduced. For the second layer three possibilities are considered: serial interface, parallel bus and local area network. The latter is carefully studied and a low cost alternative to the standard deterministic network MAP is introduced. This cell network is based on the CSMA/DCR protocol implemented on the i82596 coprocessor. Two alternatives are discussed for the programming layer: a parallel programming language based on a scene approach and a C extended language used to program elementary tasks in a robot independent way coupled with an intelligent scheduler used to assign these tasks to the robot arms at run time