3D haptic handling of microspheres

In this paper, a fully teleoperated 3D micro assembly task with haptic feedback is presented. Microspheres (diameter: 4-6μm) are manipulated by pick-and-place. The setup is composed of a dual-tip gripper controlled through a haptic interface. To grasp the spheres, the tips must be correctly positioned with respect to the objects. The approach proposed to align the gripper is based on a user-driven exploration of the to-be-manipulated object. During this step, the haptic feedback is based on amplitude measurements from cantilevers in dynamic mode. Hence, the operator perceives the contact while freely exploring the manipulation area. A virtual guide is generated to pull the user to the optimum contact point, allowing correct positioning of dual tips. For the pick-and-place operation, the haptic feedback provides the user with information about the microscale interactions occurring during the operation. As experimental validation, a two-layer pyramid composed of four nylon microspheres is built in ambient conditions.