Application of pneumatic parallel manipulator as haptic human interface

When humans and robots implement a cooperative task, information (intention) transfer between them is an important problem as the task becomes complicated. In the paper, a haptic interface using a pneumatic parallel manipulator is developed to realize "information transfer by means of contact". The contact information given by the human, namely contact force vector and contact point on the manipulator, is detected by the interface itself and such information is transferred to the robot by being connected with some reference signal. The pneumatic parallel manipulator works as a kind of elastic body even when its position is controlled owing to the air compressibility. Focusing on this characteristic and introducing an idea of compliance center with a spherical shell, contact force vector and contact point are detected without a force sensor. The validity of the proposed method is confirmed through some experiments.