A Conformable Force/Tactile Skin for Physical Human–Robot Interaction

In this letter, a new sensorized flexible skin has been used to enhance safety and intuitiveness of physical human-robot interaction (HRI) in applications where both intentional and unintentional contacts may occur. The new technological contribution with respect to other skin sensors consists of the capability of measuring both the position of the contact point and the three components of the applied force with high repeatability and accuracy. To show how this innovative technology enables the exploitation of control laws for intuitive HRI, two standard control strategies have been implemented to perform both manual guidance with multiple contact points and safe reaction in case of unintentional collision detection, at the same time. In both cases, an admittance control scheme with a second order kinematic control is adopted. A multipriority redundancy resolution strategy is implemented in the case of manual guidance. The experimental verification of the sensor capabilities is made using a patch of the skin installed on a link of a KUKA LWR4 robot.