Soft Magnetic Fingertip With Particle-Jamming Structure for Tactile Perception and Grasping

Typically, the fingertips of a dexterous robotic hand are designed to be rigid and equipped with a variety of sensors to provide tactile perception. However, this design scheme renders the grasping of small objects difficult, because rigid fingertips usually have a small contact area with the objects. In this article, we propose a novel fingertip design that combines soft tactile skin and a particle-jamming structure. Benefiting from the particle-jamming structure, the soft skin and fluid-state jamming particle material ensure that the fingertip encloses the object as much as possible when in contact with it. Then, the application of a vacuum turns the particle material into a high-stiffness solid-state, allowing it to hold objects. Soft tactile skin integrated with permanent magnetic particles estimates contact information between the fingertip and objects. Thus, utilizing the soft tactile skin and particle-jamming structure the fingertip can perceive and grasp objects simultaneously. The proposed soft fingertip module is fabricated by molding, which reduces the processing cycle time and cost. In addition, a series of experiments are conducted to demonstrate the performance of this novel fingertip design. The results validate that the proposed robotic fingertip can grasp tiny objects while perceiving contact position and force information.