Rebis Robot Design

Our main objective was to design a modular mechanism which can transform from a snake configuration into a walking configuration without any detaching and attaching modules. This eliminates the need of additional actuators and mechanism for docking and undocking the modules. Using modular architecture makes it easy to replace modules or add additional ones to increase the Degrees of Freedoms (DoF).

The figure to the right shows the image of a pair of module of the ReBiS robot. It consists of a C-Clamp, Motor Clamp and a Dynamixel MX-28 Motor. The joint has a rotation angle of +-120 degrees. Each part is custom manufactured by our team on a CNC milling machine at FMS Lab, Mechanical Department of VNIT Nagpur, under Prof. Shital Chiddarwar. The images below show the ReBiS robot during manufacturing and assembly.

The figure on the left shows the software architecture of the ReBiS robot. The implementation of the upper block is done using ROS (Robot Operation System) on ubuntu 12.04 running on a laptop. ROS framework helps us in using multi-processing along with inter-process communication. The laptop is connected to a ARM cortex M4 processor, by Texas Instruments, which communicates with the Dynamixel motors. Each Dynamixel motor is connected to TIVA using UART in a daisy chain. The angles for each gait are calculated by the gait generator node, which sends messages to the communicator node. The communicator node sends the msges to TIVA over UART, which then sends the reference positions to each Dynamixel motor.