A 3D-Printed Centimeter-Scale Pneumatically Actuated Robotic Manipulator for Micro-Manipulations

This paper presents a centimeter-scale robotic manipulator fabricated using 3D printing technology. It consists of three mechanisms: a grasping mechanism, an RCM (remote center of motion) function mechanism, and a rotational mechanism, actuated by bellows-driven soft pneumatic actuators. Thus, the robotic manipulator enables the grasping of tools for micro-manipulations and the 2-DOF orientation adjustment of the tools, including the rotation around the axis of the rotational mechanism (0° - 45°) and the rotation around an RCM (−10° - 10°). Finally, one 5-DOF robotic manipulation system consisting of the 2-DOF rotational centimeter-scale robotic manipulator and one 3-DOF translational external manipulator (moving speed ~ 500 μm/s) was used to conduct micro-manipulations, in which a printed needle was grasped to carve the desired trajectory on the agar (gel strength ~ 650 g/cm
²
) resembling biological tissues. the external manipulator controlled the displacement of the needle while the robotic manipulator adjusted the orientation of the needle insertion into the agar. Results showed that the 5-DOF robotic manipulation system had mechanical stability while achieving micron-level accuracy (200 μm) in the micro-manipulation task.