A Novel Haptic Master Manipulator With a Pneumatic-Electric Mechanism for Natural Orifice Transluminal Endoscopic Surgery

In robot-assisted natural orifice transluminal endoscopic surgery (NOTES), the surgeon adopts a master manipulator to perform complex and delicate operations. In NOTES, the position and orientation adjustment generally require 5 degrees of freedom (DoFs): 3 DoFs for rotation, 1 DoF for translation, and 1 DoF for gripping. However, commercial master manipulators are developed without a focus on the requirement of the NOTES system. Hence, most master manipulator prototypes for NOTES developed by academic researchers lack force feedback. To resolve this problem, we aim to develop a specialized master manipulator with force feedback for NOTES, which has 5 DoFs, performing deflection, rotation, translation, and gripping motions. The pneumatic actuator was innovatively developed to serve as force feedback units, and a pneumatic (airbag brake)-electric (torque motor) mechanism was designed to realize real-time force feedback for each controlled DoF. From the measurement results, the airbag brake exhibits good dynamic response characteristics (the average response time is 530.7 ms), and the airbag brake can provide a 6.0 N output force. We also evaluate the performance of the system for master–slave operation. Experimental results demonstrate the effectiveness of force feedback and indicate the potential of applying the presented haptic master manipulator for NOTES.