Wrist-Squeezing Force Feedback Improves Accuracy and Speed in Robotic Surgery Training

Current robotic minimally invasive surgery (RMIS) platforms provide surgeons with no haptic feedback of the robot's physical interactions. This limitation forces surgeons to rely heavily on visual feedback and can make it challenging for surgical trainees to manipulate tissue gently. Prior research has demonstrated that haptic feedback can increase task accuracy in RMIS training. However, it remains unclear whether these improvements represent a fundamental improvement in skill, or if they simply stem from re-prioritizing accuracy over task completion time. In this study, we provide haptic feedback of the force applied by the surgical instruments using custom wrist-squeezing devices. We hypothesize that individuals receiving haptic feedback will increase accuracy (produce less force) while increasing their task completion time, compared to a control group receiving no haptic feedback. To test this hypothesis, N=21 novice participants were asked to repeatedly complete a ring rollercoaster surgical training task as quickly as possible. Results show that participants receiving haptic feedback apply significantly less force (0.67 N) than the control group, and they complete the task no faster or slower than the control group after twelve repetitions. Furthermore, participants in the feedback group decreased their task completion times significantly faster (7.68%) than participants in the control group (5.26%). This form of haptic feedback, therefore, has the potential to help trainees improve their technical accuracy without compromising speed.Comment: 6 figures, 8 page

Dual-Modality Haptic Feedback Improves Dexterous Task Execution with Virtual EMG-Controlled Gripper

Upper-extremity amputees who use myoelectric prostheses currently lack the haptic sensory information needed to perform dexterous activities of daily living. While considerable research has focused on restoring this haptic information, these approaches often rely on single-modality feedback schemes which are necessary but insufficient for the feedforward and feedback control strategies employed by the central nervous system. Multi-modality feedback approaches have been gaining attention in several application domains, however, the utility for myoelectric prosthesis use remains unclear. In this study, we investigated the utility of dual-modality haptic feedback in a virtual EMG-controlled grasp-and-hold task with a brittle object and variable load force. We recruited N=20 non-amputee participants to perform the task in four conditions: no feedback, vibration feedback of incipient slip, squeezing feedback of grip force, and dual (vibration + squeezing) feedback of incipient slip and grip force. Results suggest that receiving any feedback is better than receiving none, however, dual-modality feedback is far superior to either single-modality feedback approach in terms of preventing the object from breaking or dropping, even after it started slipping. Control with dual-modality feedback was also seen as more intuitive than with either of the single-modality feedback approaches

Handheld Devices for Laparoscopic Surgery

Despite the well-known benefits of minimally invasive surgery (MIS) to the patients, this surgical technique implies some technical challenges for surgeons. These technical limitations are increased with the introduction of laparoendoscopic single-site (LESS) surgery. In order to overcome some of these technical difficulties, new handheld devices have been developed, providing improved functionalities along with precision-driven and articulating instrument tips. In this chapter, we will review the current status of handheld devices for laparoscopy and LESS surgery. Devices that provide additional and innovative functionalities in comparison with conventional surgical instruments will be considered. Results will be based on studies published in the scientific literature and our experience. These surgical devices will be organized into two main groups, mechanical devices and robotic-driven devices. In general, these instruments intend to simulate the dexterity of movements of a human wrist. Mechanical devices are cheaper and easier to develop, so most of the available handheld instruments fall into this category. The majority of the robotic-driven devices are needle holders with an articulating tip, controlled by an interface implemented on the instrument handle. In general, these handheld devices claim to offer an enhancement of dexterity, precision, and ergonomics

A robotic microsurgical forceps for transoral laser microsurgery

Purpose: In transoral laser microsurgery (TLM), the close curved cylindrical structure of the laryngeal region offers functional challenges to surgeons who operate on its malignancies with rigid, single degree-of-freedom (DOF) forceps. These challenges include surgeon hand tremors, poor reachability, poor tissue surface perception, and reduced ergonomy in design. The integrated robotic microsurgical forceps presented here is capable of addressing the above challenges through tele-operated tissue manipulation in TLM. Methods: The proposed device is designed in compliance with the spatial constraints in TLM. It incorporates a novel 2-DOF motorized microsurgical forceps end-effector, which is integrated with a commercial 6-DOF serial robotic manipulator. The integrated device is tele-operated through the haptic master interface, Omega.7. The device is augmented with a force sensor to measure tissue gripping force. The device is called RMF-2F, i.e. robotic microsurgical forceps with 2-DOF end-effector and force sensing. RMF-2F is evaluated through validation trials and pick-n-place experiments with subjects. Furthermore, the device is trialled with expert surgeons through preliminary tasks in a simulated surgical scenario. Results: RMF-2F shows a motion tracking error of less than 400 μm. User trials demonstrate the device’s accuracy in task completion and ease of manoeuvrability using the Omega.7 through improved trajectory following and execution times. The tissue gripping force shows better regulation with haptic feedback (1.624 N) than without haptic feedback (2.116 N). Surgeons positively evaluated the device with appreciation for improved access in the larynx and gripping force feedback. Conclusions: RMF-2F offers an ergonomic and intuitive interface for intraoperative tissue manipulation in TLM. The device performance, usability, and haptic feedback capability were positively evaluated by users as well as expert surgeons. RMF-2F introduces the benefits of robotic teleoperation including, (i) overcoming hand tremors and wrist excursions, (ii) improved reachability and accuracy, and (iii) tissue gripping feedback for safe tissue manipulation

Effects of Haptic Feedback on the Wrist during Virtual Manipulation

As an alternative to thimble devices for the fingertips, we investigate haptic systems that apply stimulus to the user's forearm. Our aim is to provide effective interaction with virtual objects, despite the lack of co-location of virtual and real-world contacts, while taking advantage of relatively large skin area and ease of mounting on the forearm. We developed prototype wearable haptic devices that provide skin deformation in the normal and shear directions, and performed a user study to determine the effects of haptic feedback in different directions and at different locations near the wrist during virtual manipulation. Participants performed significantly better while discriminating stiffness values of virtual objects with normal forces compared to shear forces. We found no differences in performance or participant preferences with regard to stimulus on the dorsal, ventral, or both sides of the forearm.Comment: 7 pages, submitted conference paper for IEEE Haptics Symposium 202

Effects of Haptic Feedback on the Wrist during Virtual Manipulation

We propose a haptic system for virtual manipulation to provide feedback on the user's forearm instead of the fingertips. In addition to visual rendering of the manipulation with virtual fingertips, we employ a device to deliver normal or shear skin-stretch at multiple points near the wrist. To understand how design parameters influence the experience, we investigated the effect of the number and location of sensory feedback on stiffness perception. Participants compared stiffness values of virtual objects, while the haptic bracelet provided interaction feedback on the dorsal, ventral, or both sides of the wrist. Stiffness discrimination judgments and duration, as well as qualitative results collected verbally, indicate no significant difference in stiffness perception with stimulation at different and multiple locations.Comment: 2 pages, work-in-progress paper on haptics symposium, 202