Dynamic Model of a Bio-Inspired Robot for Piping Inspection

Piping inspection robots are of great importance in industries such as nuclear, sewage and chemical where the internal diameters of the pipeline are significantly smaller. Mechanisms having closed loops can be used in such areas as they generate contact forces and deployable structures. With the help of a bio-inspired mechanism, a piping inspection robot is presented which mimics the motion of a caterpillar. The robot is composed of three modules: a central module for elongation and two other modules on the front and rear for clamping. A slot-slider mechanism is chosen for the legs of the robot. Using industrial components such as DC motors, servo-controllers, ball screws and fasteners, the entire robotic system was realized in CATIA software and a prototype was made at the Laboratoire des Sciences du Numérique de Nantes (LS2N). In this article, we present the forces induced on the motors under locomotion using a dynamic analysis. With the help of the recursive Newton-Euler algorithm, the torques generated on the motor under locomotion have been identified which ensures the stability of the system while moving inside pipes.