Design of a MagneticallyDriven Untethered MicroGripper for Drug Delivery Microgrippers have great potential to be used in robotassisted surgery. They can go through small vessels and natural orifice, which makes them a good choice for drug delivery or treatment. Magnetic field can exert forces and torques that cross nonmetallic substances and has no harm to organism. As a result, magneticallydriven microgripper can be a good candidate for clinical practice. In order to apply these advantages to drug delivery, a magneticallydriven controllable untethered microgripper is designed. Two small permanent magnets are assembled together with a certain angle to response the magnetic fields. Based on the principle that the magnetic fields exert torques and forces, we set up a control model of the microgripper. In opening and closing experiment, the current version of microgripper can open about 20xe2x97xa6 in a 18mT magnetic fields generated by 11A current in our coil system. Moreover, we achieve the move control of the microgripper. The orientation and movement can be controlled by controlling of the external magnetic field. In the movement experiment and the drug delivery experiment, the microgripper has shown a good performance. This study give a new research on microgripper used to drug delivery.

Magnetically Driven Wireless Capsule Robot with Targeting Biopsy Function In this work, we present a novel magnetically actuated wireless capsule robot with biopsy function based on the principle of magnetic torsion spring (MTS). MTS is a simple device consisting of two ringshape permanent magnets inside the capsule. It can be remotely controlled by an external uniform magnetic field so that the biopsy tool can be extended from the capsule to perform biopsy sampling operations. The energy required for biopsy is all provided by the external magnetic driving system without the need to consume the battery energy of the capsule itself. Magnetic finite element analysis is conducted to design MTS. Kinematics and force analysis of the biopsy tools is also provided. Finally, a pillshape prototype of capsule robot is manufactured with dimension of 14 mm in diameter and 32 mm in length. In vitro experiments were carried out with this prototype to verify the feasibility of the biopsy module mechanism design and to test the ability for active locomotion.