Dexterous vibrationless micromanipulation by magnetic-field driven micro-gripper

High-speed motion will cause vibration of micromanipulators constructed by liner stages and liner motors, which affects the stability and precision of micromanipulation a lot. In this paper, we proposed a dexterous vibrationless two-finger micro-gripper driven by magnetic field. The system included one fixed micropipette and the other active micropipette with the ferromagnetic beads inside which will force the micropipette as a cantilever to deform in the magnetic field generated by the electromagnet. The applied current and the protrusion length of the micropipette were utilized to control the movement of the active micropipette tip and the grasping/releasing motion of the micro-gripper. We also proposed an active release method of the micro-object through driving the active micropipette to vibrate at a high speed for overcoming the adhesion force between the targets and the micropipette tips. The experimental results show that the micropipette driven by the magnetic-field can move stably at an extreme high speed without any extra vibration due to the magnetic driven force used in the micromanipulation system, and the proposed micro-gripper can realize dexterous grasping and releasing of the microbeads in micro scale. Besides the proposed active release method can release the microbeads that stick on the micropipette tip successfully in micro scale.