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Surgical robots have had clinical use since the mid 1990s. Robot-assisted surgeries offer many benefits over the conventional approach including lower risk of infection and blood loss, shorter recovery, and an overall safer procedure for patients. The past few decades have shown many emerging surgical robotic platforms that can work in complex and confined channels of the internal human organs and improve the cognitive and physical skills of the surgeons during the operation. Advanced technologies for sensing, actuation, and intelligent control have enabled multiple surgical devices to simultaneously operate within the human body at low cost and with more efficiency. Despite advances, current surgical intervention systems are not able to execute autonomous tasks and make cognitive decisions that are analogous to that of humans. This paper will overview a historical development of surgery from conventional open to robotic-assisted approaches with discussion on the capabilities of advanced intelligent systems and devices that are currently implemented in existing surgical robotic systems. It will also revisit available autonomous surgical platforms with comments on the essential technologies, existing challenges, and suggestions for the future development of intelligent robotic-assisted surgical systems towards the achievement of fully autonomous operation., Comment: 76 pages, 23 figures, 1 table

In this study, a new position control scheme for the tendon-sheath mechanism (TSM) which is used in flexible medical devices is presented. TSM is widely used in dexterous robotic applications because it can flexibly work in limited space, in constrained environments, and provides efficient power transmission from the external actuator to the distal joint. However, nonlinearities from friction and backlash hysteresis between the tendon and the sheath pose challenges in achieving precise position controls of the end effector. Previous studies on the TSM only address the control problem under the assumptions of known tendon-sheath configuration and known model parameters of the backlash hysteresis nonlinearity. These approaches can have adverse impact and limitations on the overall system performances and practical implementation. This paper presents a new approach to model and control the TSM-driven flexible robotic systems. The designed controller does not require exact knowledge of nonlinear friction and backlash hysteresis parameters, only their bounds are online estimated. Simulation and experimental validation results show that the proposed control scheme can significantly improve the tracking performances without the presence of the exact knowledge of the model parameters and the sheath configuration., Comment: 8 pages, 11 figures

Flexible tendon sheath mechanism is commonly used in NOTES systems because it offers high flexibility, light weight, and easy transmission. Due to the size constraints and sterilization problems, traditional sensors like force/torque sensor are extremely difficult to place at the tool tips of surgical arms. In addition, nonlinear dynamic friction and backlash cause challenges to provide haptic feedback to the surgeons when the robotic arms are inside the patient's body. Hence, it is extremely difficult to provide the force information to haptic devices and subsequently to the surgeons. To deal with these problems, in this paper we propose a new approach of friction model in the tendon-sheath mechanism to provide the force at distal end of endoscopic system. In comparison with current approaches in the literature, the proposed model is able to provide force information at zero velocity and it is smooth. In addition, the model is independent configuration and able to capture friction force with any complex sheath shapes. A suitable experimental setup is established to validate the proposed approach using the two degrees of freedom Master-Slave system. The validity of the proposed approach is confirmed with a good agreement between the estimated model and real experimental data. Finally, a force feedback structure is also given for use in flexible endoscopic systems., Comment: 12 pages, 10 figures