Dynamic modeling of three-finger micro-tweezers for grasping microparticles

For regenerative medicine and tissue engineering to advance, it has been necessary to develop technologies to handle microscopic biological samples such as cells and spheroids. One popular method for manipulating such samples in the fields of nano and biotechnology is the use of micro and nano-tweezers. This paper discusses the design and dynamic modeling of three-finger microtweezers, which are a type of nano-wire manufactured electromechanical tweezers. The article introduces an innovative technique for operating tweezers, which involves using high-frequency alternation to achieve symmetrical deformation of the arms. Due to the complexity of the technique, especially for an odd number of fingers, an analytical solution is not feasible, and a simplified simulation is presented instead. The system, crucially, is shown to seamlessly integrate with the COMSOL Multiphysics interfaces, a critical aspect that helps to generalize, stabilize, and streamline the implementation process. The simulation results are validated by comparing them with the available experimental data. Subsequently, the impact of geometric parameters on dynamic behavior is investigated. Finally, the behavior of the proposed nano-tweezers is compared to that of conventional two-armed tweezers.