Benchmarking of Comfort and Learnability of a New Soft Robotic Tool for Key-hole Surgery

Laparoscopic surgery requires precise and time consuming procedures to be performed. These procedures involve awkward poses in the upper body as well as the hands and fingers of the surgeons. STIFF-FLOP is an ongoing EU FP7 project that proposes the creation of a stiffness controllable soft robotic manipulator for laparoscopic surgery. The manipulator is proposed to help laparoscopic surgeons and their patients by simplifying the tasks involved and reducing risk of errors. This paper reports on a series of tests performed as part of a study into the new soft manipulator’s ease of use and level of required effort as well as learnability. The study was performed on a limited prototype of the manipulator. Surface EMG of the forearm muscles was used to benchmark effort and comfort and questionnaires were provided for subjective assessment. Participants (n=25) were timed and their muscles activities recorded for comparison. Results show that the average rms EMG levels were 25.9% less with the STIFF-FLOP manipulator when compared with conventional laparoscopic tools. On a second attempt with the STIFF-FLOP manipulator participants spent an average of 32.1% less time, showing the manipulator’s learnability and ease of adaptation. Further details and analysis of results are provided within the paper. Keywords— minimally invasive surgery, electromyography, comfort, learnability, benchmarking, robotic surgery