Soft materials for robotic fingers

Three potential problems exist in multifingered hands. The impact forces that result during each instant of grasping a rigid object can affect the functioning of the finger tip sensor. A hand with hard fingers cannot securely grasp objects that have uneven surfaces due to the poor conformability of the fingers. Repetitive strains are induced into the fingers throughout manipulation task. Carefully chosen materials-plastic, rubber sponge, a fine powder, a paste, and a gel-were experimentally compared for their ability to overcome these three problems. Results showed that sponge is the most suitable and plastic is the least suitable for the application. For practical reasons, however, the gel was a good compromise over the sponge. It is recommended that future robotic hands constitute a soft finger or at least fingers with soft tips, constructed out of carefully chosen materials.>