Precise and High-Load Capacity Miniature 6-DOF Manipulator for Microsurgery

Miniaturized manipulators are invaluable for microsurgery; however, they often face limitations in precision, load capacity, and Degrees of Freedom (DOFs) due to size and weight constraints. In this article, we introduce a 6-DOF mini manipulator designed to address these challenges. Powered by cost-effective stepper linear motion modules, the proposed device incorporates a dual-plane mechanism for 4-DOF
XY
motion. We also innovatively integrated a compliant 2-DOF rod drive system for
Z
-axis rotation and translation. The manipulator's forward/inverse and remote center of motion kinematics models are provided. Furthermore, we developed a microsurgical platform equipped with microvision sensing and remote-control functions. This manipulator, which weighs less than 72 g, enables precise 6-DOF control for tools with diameters less than 0.5 mm. It delivers more than 3 N of thrust force along the compliant rod drive axis, achieving at least 10
μ
m motion resolution and a 9 N maximum output force per DOF. Rigorous testing was performed, demonstrating the system's ability to successfully perform puncture and drilling operations on porcine skin and bone. Additionally, we showed its effectiveness in ocular surgeries, demonstrating its potential for use as a cost-effective, portable device in minimally invasive procedures.