Haptics in Robot-Assisted Surgery: Challenges and Benefits

Robotic surgery is transforming the current surgical practice, not only by improving the conventional surgical methods but also by introducing innovative robot-enhanced approaches that broaden the capabilities of clinicians. Being mainly of man-machine collaborative type, surgical robots are seen as media that transfer pre- and intra-operative information to the operator and reproduce his/her motion, with appropriate filtering, scaling, or limitation, to physically interact with the patient. The field, however, is far from maturity and, more critically, is still a subject of controversy in medical communities. Limited or absent haptic feedback is reputed to be among reasons that impede further spread of surgical robots. In this paper objectives and challenges of deploying haptic technologies in surgical robotics is discussed and a systematic review is performed on works that have studied the effects of providing haptic information to the users in major branches of robotic surgery. It has been tried to encompass both classical works and the state of the art approaches, aiming at delivering a comprehensive and balanced survey both for researchers starting their work in this field and for the experts

Evaluation of sensor configurations for robotic surgical instruments

Designing surgical instruments for robotic-assisted minimally-invasive surgery (RAMIS) is challenging due to constraints on the number and type of sensors imposed by considerations such as space or the need for sterilization. A new method for evaluating the usability of virtual teleoperated surgical instruments based on virtual sensors is presented. This method uses virtual prototyping of the surgical instrument with a dual physical interaction, which allows testing of different sensor configurations in a real environment. Moreover, the proposed approach has been applied to the evaluation of prototypes of a two-finger grasper for lump detection by remote pinching. In this example, the usability of a set of five different sensor configurations, with a different number of force sensors, is evaluated in terms of quantitative and qualitative measures in clinical experiments with 23 volunteers. As a result, the smallest number of force sensors needed in the surgical instrument that ensures the usability of the device can be determined. The details of the experimental setup are also included

Tactile feedback display with spatial and temporal resolutions.

We report the electronic recording of the touch contact and pressure using an active matrix pressure sensor array made of transparent zinc oxide thin-film transistors and tactile feedback display using an array of diaphragm actuators made of an interpenetrating polymer elastomer network. Digital replay, editing and manipulation of the recorded touch events were demonstrated with both spatial and temporal resolutions. Analog reproduction of the force is also shown possible using the polymer actuators, despite of the high driving voltage. The ability to record, store, edit, and replay touch information adds an additional dimension to digital technologies and extends the capabilities of modern information exchange with the potential to revolutionize physical learning, social networking, e-commerce, robotics, gaming, medical and military applications

Incipient slip detection and grasping automation for robotic surgery

Robotic minimally invasive surgery provides multiple improvements over traditional laparoscopic procedures, but one significant issue still encountered is their limited force control during the grasping and retraction of tissue, as the surgeon is separated from the instrument, and therefore denuded of their sense of touch and the applied forces. Prior solutions have largely looked towards haptic feedback to resolve this issue, but an alternative approach is to detect and monitor the occurrence of tissue slip events. This would allow the force to be automatically adjusted to prevent slip, minimising the clamp force used to maintain control, thus reducing the probability of tissue trauma. The aim of this work is to develop a method for the early detection and mitigation of tissue slip during robotic surgical manipulation tasks, helping to reduce tissue trauma and minimise tissue slip events. Initial investigations into literature, and evaluation of the slip mechanics when grasping soft, lubricated, deformable materials, indicated that small localised slips occur before the onset of macro slip. Two phenomena were identified in the slip mechanics investigation that could be employed to induce these slip in a measurable and repeatable manner. Firstly through using the tissue's deformable properties to create slip differentials between the front and rear of the grasper face, and secondly through using a curved surface to create a variation in the normal force, and thus frictional force, across the surface. Two instrumented grasper faces were developed, based on each of these phenomena, that were capable of monitoring the occurrence of localised tissue slip through monitoring the displacement of a series of independent movable islands that made up the grasper face. These were then demonstrated to be capable of automatically detecting slip events for a range of test conditions with tissue simulants, before being utilised to automatically control the grasping forces during a tissue retraction task. Both sensor systems provided similar levels of tissue control to one which utilised the maximum clamp force throughout the task, whilst applying lower forces during the early stages of retraction, reducing the probability of tissue damage. In addition the normal force based method, with the curved grasper face, was demonstrated to be effective for the early detection of slip when grasping porcine liver tissue, successfully detecting incipient slip in 77% of cases. This work provides a strong basis for further development of incipient slip sensing for surgical applications. It provides novel contributions in the understanding of slip mechanics of soft tissues, as well as presenting two separate novel sensing approaches for the automatic detection and mitigation of slip events, offering an opportunity for reducing the occurrence of tissue slip events whilst minimising tissue trauma, as well as surgeon fatigue

Kinesthetic Feedback for Robot-Assisted Minimally Invasive Surgery (Da Vinci) with Two Fingers Exoskeleton

Minimally Invasive Surgery and, in particular, Robotic Minimally Invasive Surgery may benefit from the integration of Haptic device: here we propose a preliminary study on a two-finger exoskeleton for kinesthetic feed-back of surgeon thumb and index finger while controlling a Da Vinci Robotic Device through its Master Tool Manipulator (MTM). Simulation of contact be-tween rigid and soft objects with the Patient Side Manipulator (PSM) are inte-grated with Force Feedback on the MTM coupled with the exoskeleton