A Two-DOF Impact Actuator for Haptic Interaction

This paper presents a new actuator mechanism that can create a planar two-DOF impact and vibrotactile stimuli with wide frequency bandwidth. The proposed device utilizes one permanent magnet and two different sets of solenoids, direction controlling solenoids and a central solenoid. The direction controlling solenoids are two sets of facing solenoid pair, which attract the permanent magnet from a neutral position toward the housing, to create an impact. The central solenoid increases the magnet’s potential energy, resulting in a faster movement toward the outside of the neutral position and thus increasing the amount of impact. The central solenoid can be utilized to create an attractive force to move the magnet back to the neutral position after the impact. When creating an impact in an arbitrary orientation, two sets of solenoid pair are used to decide the initial force direction, which is parallel to the magnet’s trajectory until an impact. The actuator can be used as a tactor by controlling the impact cycle.