Contact sensing methodology based on propagation of interaction-induced deformation in elastic beams

Owing to the capability of environment perception, contact sensors are increasingly used in robotic systems to enhance their ability to interact with the environment. This paper proposes a simple contact sensing methodology based on the continuum mechanics of largely deformed beams. Slender elastic beams embedded with flexible strain gauges are employed as the sensing medium for contact perception. An explicit model characterizing the beam’s force-deflection behavior is established to map the local bending of strain gauges to the contact-induced global deformation. Thus, the exact status of contact positions and forces can be determined efficiently. A variety of experiments are conducted to validate the effectiveness of the developed contact sensor. In addition to contact perception, the elastic beam endows robotic systems with structural compliance for interactive manipulation. Hence, applications for object size identification, active control of contact force, and force-based collaboration are provided to exhibit the potential of the proposed contact sensing methodology in mobile robots.