A Distributed Control System for Spatial Hyper Redundant Robot using CAN

Spatial Hyper Redundant (SHR) robot has more controllable DOF than actual DOF due to hyper redundancy. The robot has increased dexterity and is well known for its use in unstructured environments. Due to higher controllable DOF, control system becomes extremely complex to implement. Hence, to develop the same, Controller Area Network (CAN) protocol which enables lesser number of bus signals and quite suitable in an environment where large number of microprocessor based systems are employed is used. In this case, stepper motors are used to actuate the links. This research involves in design of control system for an 8 link snake like robot using CAN protocol. A node consists of a microcontroller, CAN controller, CAN transceiver and a physical medium for transmission. A PIC 18F458 is chosen as the microcontroller which has inbuilt CAN module and it is programmed using CCS compiler for the application. The CAN communication was established by sending data from one node to other for physically actuating motions of links at its initial phase and then it was extended for multiple nodes with one node as master interfaced to GUI using RS232 on one side and to other nodes through CAN. Implementation of message filtering was done for each node. Performance of the system was also studied for multiple nodes of the system.