Shape Localization and Recognition Using a Magnetorheological-Fluid Haptic Display

Enhancing the Localization of Uterine Leiomyomas Through Cutaneous Softness Rendering for Robot-Assisted Surgical Palpation Applications

Integrating tactile feedback for lump localization in Robot-assisted Minimally Invasive Surgery (RMIS) represents an open research issue, which is still far to be solved. Main reasons for this are related e.g. to the need for a transparent connection with the teleoperating console, and an intuitive decoding of the delivered information. In this article, we focus on the specific case of RMIS treatment of uterine leiomyomas or fibroids, where little has been done in haptics to improve the outcomes of robotics-enabled palpation tasks. In this article, we propose the usage of a wearable haptic interface for softness rendering as a lump display. The device was integrated in a teleoperation architecture that simulates a robot-assisted surgical palpation task of leiomyomas. This article moved from an ex-vivo sample characterization of uterine tissues to show the effectiveness of our interface in conveying meaningful softness information. We extensively tested our system with gynecologic surgeons in palpation tasks with silicone specimens, which replicated the characteristics of uterine tissues with embedded leyomiomas. Results show that our system enables a softness-based discrimination of the embedded fibroids comparable to the one that physicians would achieve using directly their fingers in palpation tasks. Furthermore, the feedback provided by the haptic interface was perceived as comfortable, intuitive, and highly useful for fibroid localization.

Haptic Actuation Plate for Multi-Layered In-Vehicle Control Panel

High-fidelity localized feedback has the potential of providing new and unique levels of interaction with a given device. Achieving this in a cost-effective reproducible manner has been a challenge in modern technology. Past experiments have shown that by using the principles of constructive wave interference introduced by time offsets it is possible to achieve a position of increased vibration displacement at any given location. As new interface form factors increasingly incorporate curved surfaces, we now show that these same techniques can successfully be applied and mechanically coupled with a universal actuation plate.

Haptic Intracorporeal Palpation Using a Cable-Driven Parallel Robot: A User Study

OBJECTIVE

Intraoperative palpation is a surgical gesture jeopardized by the lack of haptic feedback which affects robotic minimally invasive surgery. Restoring the force reflection in teleoperated systems may improve both surgeons' performance and procedures' outcome.

METHODS

A force-based sensing approach was developed, based on a cable-driven parallel manipulator with anticipated seamless and low-cost integration capabilities in teleoperated robotic surgery. No force sensor on the end-effector is used, but tissue probing forces are estimated from measured cable tensions. A user study involving surgical trainees (n = 22) was conducted to experimentally evaluate the platform in two palpation-based test-cases on silicone phantoms. Two modalities were compared: visual feedback alone and both visual + haptic feedbacks available at the master site.

RESULTS

Surgical trainees' preference for the modality providing both visual and haptic feedback is corroborated by both quantitative and qualitative metrics. Hard nodules detection sensitivity improves (94.35 ± 9.1% vs 76.09 ± 19.15% for visual feedback alone), while also exerting smaller forces (4.13 ± 1.02 N vs 4.82 ± 0.81 N for visual feedback alone) on the phantom tissues. At the same time, the subjective perceived workload decreases.

CONCLUSION

Tissue-probe contact forces are estimated in a low cost and unique way, without the need of force sensors on the end-effector. Haptics demonstrated an improvement in the tumor detection rate, a reduction of the probing forces, and a decrease in the perceived workload for the trainees.

SIGNIFICANCE

Relevant benefits are demonstrated from the usage of combined cable-driven parallel manipulators and haptics during robotic minimally invasive procedures. The translation of robotic intraoperative palpation to clinical practice could improve the detection and dissection of cancer nodules.

Healable Thermoplastic for Kinesthetic Feedback in Wearable Haptic Devices

The word "haptics" refers to technologies designed to stimulate the tactile and kinesthetic senses. Kinesthesia-the sense of motion-is triggered by imposing forces upon the joints, tendons, and muscles to recreate the geometry and stiffness of objects, as may be useful in physical therapy or virtual reality. Here, we introduce a form of kinesthetic feedback by manipulating the mechanical properties of spandex impregnated with a thermoplastic polymer. Heating or cooling this textile-thermoplastic composite just above or below its glass transition temperature (T g) dramatically changes its mechanical properties (corresponding to a decrease in storage modulus from 36 MPa to 0.55 MPa). In the form of a glove, the composite can also be healed after inadvertent overextension in its stiffened state by heating it above its T g. When fitted with thermoelectric devices for active heating and cooling, the flexible or stiffened state of a glove can be perceived by human subjects. As an example of a human-machine interface, the glove is used to control a robotic finger. When the robotic finger makes contact with a wall, a signal is sent to thermoelectric devices in the glove to cool (stiffen the finger) and thus provide kinesthetic feedback to the user.