Development of Force Sensing Techniques for Robot-Assisted Laparoscopic Surgery: A Review

Robot-assisted laparoscopic surgery (RALS) has been widely investigated and developed as a routine and preferred minimally invasive surgery (MIS) because of enhanced operational precision and dexterity, improved visualization, and reduced surgeon stress and fatigue. However, the lack of force feedback poses challenges to accurate interaction force perception, lowered surgical errors, improved patient safety, and upgraded surgical outcomes. The solutions to force sensing can empower surgeons with a more intuitive and natural surgical experience with accurate perception capacity of interaction forces, efficient motor skill acquisition, enhanced surgical quality, and support the development of high-level techniques for surgical intelligence and autonomy. Although extensive research has been investigated in this field, effective and solid solutions are still unavailable for actual surgical scenarios. This review provides a comprehensive investigation from starting implementations to recent advances in emerging techniques for physical force sensors in laparoscopic surgery and RALS and focuses on the following categories: strain gauge-based, capacitive-based, and optical fiber-based principles. The design of force-sensitive structures from the mechanism perspective has been emphasized to provide possible and valuable design guidance for force sensor implementations with expected performance. Merits and limitations of existing technologies and prospects of new technologies are also discussed.