Effect of backlash on surgical robotic task proficiency

Teleoperated surgical robot designs, particularly those utilizing cable drive mechanisms, often exhibit motion backlash. This paper presents an experiment that investigates how backlash affects proficiency in basic surgical skills. Backlash was added to the Laprotek surgical robot using software, and subjects completed three Fundamentals of Laparoscopic Surgery (FLS) tasks. Three subjects performed the tasks under five different levels of system backlash (1, 5, 10, 15, and 20 mm). Subjects were able to complete the tasks with all levels of backlash. A linear relationship was observed between the amount of backlash in the system and task completion time. On average, completion times increased by 5% for every 1 mm of additional backlash in the system.