Force estimation via physical properties of air cushion for the control of a human-cooperative robot: basic experiments

For the control of a human-cooperative robot (HCR) using a soft material, we aim to verify, in this study, the usefulness of force estimation via physical properties of an air cushion. First, the physical model of the air cushion was represented by an air cylinder with a piston, which is subject to constraint by nonlinear elasticity. Second, the elastic properties of the air cushion were examined under the assumption that it can be formulated by a function of pneumatic pressure. The force applied to the air cushion was next estimated on the basis of the physical model, and the HCR was successfully controlled according to the estimated force. Graphical Abstract