Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Analysis of compliant joints for planar legged robots
Submission Author:
Cristiane Tonetto , ES , Brazil
Co-Authors:
Cristiane Tonetto, Henrique Simas
Presenter: Cristiane Tonetto
doi://10.26678/ABCM.COBEM2021.COB2021-0862
Abstract
In the last years there was a considerable advance on mobile robotics. Wheeled robots found limitations while navigating on uneven or rough terrains. These limitations and the observed movements capacity of legged animals provide good insights for researchers looking for modeling and building bio-inspired legged robots. Bio-inspired robots should have some complacency during the movement of its structure while following the planned trajectory. The purpose of this article is to evaluate the behavior of a planar robot with three revolute joints with added compliant elements on its system. There should be external forces to the system, representing the body’s weight, in order to verify the system’s response regarding torques, keeping the system in static equilibrium, as well as regarding position/speeds. In order to achieve these results a procedure will be followed to couple the kinematics and statics. For the analysis development, screw theory and Davies method is going to be applied. The screw theory allows a simple and essential view of the behavior of bodies and joints, and it is possible to make parallels between instantaneous kinematics by one hand and statics by another. This way, it is possible to work on angular and linear velocities, forces and moments. Davies method is applied to static and kinematics analysis of the mechanism. The use of compliant elements will be made while applying kinematics targeting joints position, and the forces and moments are produced as a result for the compensations that holds the system equilibrium. The analysis of the results for compliant elements on joints will allow the evaluation of variable stiffness actuator, so that it will be possible to add complacent joints on structures that were primarily build with no complacency. Finally, as a work in progress, a systematic could be developed, with generalization for spatial robotic systems.
Keywords
legged robot, compliance, kinetostatic, Davies method
