Origami-inspired miniature manipulator for teleoperated microsurgery

Robot-assisted microsurgery promises high stability and accuracy for instance in eye- or neurosurgery applications. A new miniature robotics device, based on an origami-inspired design, can make complex 3D motions and reaches a precision of around 26 micrometres. The use of a structure with a remote fixed point around which a mechanism can rotate is called remote centre of motion (RCM). The technique is widely used in minimally invasive surgery to avoid excess force on the incision site during the robot's motion. Here we describe the design, fabrication and characterization of an origami-inspired miniature RCM manipulator for teleoperated microsurgery (the mini-RCM has mass 2.4 g and size 50 mm x 70 mm x 50 mm), which is actuated by three independently controlled linear actuators with concomitant sensing (each mini-LA has mass 0.41 g and size 28 mm x 7 mm x 3.6 mm). The mini-RCM has a payload capacity of approximately 27 mN and attains a positional precision of 26.4 mu m. We demonstrate its potential utility as a precise tool for teleoperated microsurgery by performing 0.5-mm-square tracing and micro-cannulation teleoperated microsurgical procedures under a microscope. Teleoperation using the mini-RCM reduced the deviation from the desired trajectory by 68% compared to manual operation. In addition, the mini-RCM allows gravity compensation and back drivability for safety. Its compact, simple structure facilitates manufacture.