A low-stress and low temperature gradient microgripper for biomedical applications

Microelectromechanical systems based micro gripper is one of the major focuses for many medical applications such as microsurgery, micro assembling and testing of micro components, and measuring properties of biological cells as well as small-scale tissue manipulation. This paper presents an electrostatically actuated micro gripper. Different materials sets (Si/SiO₂ and polysilicon/Si₃N₄) were investigated to design electrostatic comb drive micro gripper. The main characteristics of the micro gripper were analyzed using a finite element model (ANSYS software). These characteristics include; the maximum displacement of gripper arms, stresses in the micro gripper, the gripping force, and heat generated from joule heating. It is demonstrated that the proposed design will produce negligible increase in temperature and stresses developed during operation because of applying the actuation voltage.