1,720,998 research outputs found
Sensory subtraction in robot-assisted surgery: fingertip skin deformation feedback to ensure safety and improve transparency in bimanual haptic interaction
No full textThis study presents a novel approach to force feedback in robot-assisted surgery. It consists of substituting haptic stimuli, composed of a kinesthetic component and a skin deformation, with cutaneous stimuli only. The force generated can then be thought as a subtraction between the complete haptic interaction, cutaneous, and kinesthetic, and the kinesthetic part of it. For this reason, we refer to this approach as sensory subtraction. Sensory subtraction aims at outperforming other nonkinesthetic feedback techniques in teleoperation (e.g., sensory substitution) while guaranteeing the stability and safety of the system. We tested the proposed approach in a challenging 7-DoF bimanual teleoperation task, similar to the Pegboard experiment of the da Vinci Skills Simulator. Sensory subtraction showed improved performance in terms of completion time, force exerted, and total displacement of the rings with respect to two popular sensory substitution techniques. Moreover, it guaranteed a stable interaction in the presence of a communication delay in the haptic loop
Cutaneous feedback of fingertip deformation and vibration for palpation in robotic surgery
No full textDespite its expected clinical benefits, current teleoperated surgical robots do not provide the surgeon with haptic feedback largely because grounded forces can destabilize the system's closed-loop controller. This paper presents an alternative approach that enables the surgeon to feel fingertip contact deformations and vibrations while guaranteeing the teleoperator's stability. We implemented our cutaneous feedback solution on an Intuitive Surgical da Vinci Standard robot by mounting a SynTouch BioTac tactile sensor to the distal end of a surgical instrument and a custom cutaneous display to the corresponding master controller. As the user probes the remote environment, the contact deformations, dc pressure, and ac pressure (vibrations) sensed by the BioTac are directly mapped to input commands for the cutaneous device's motors using a model-free algorithm based on look-up tables. The cutaneous display continually moves, tilts, and vibrates a flat plate at the operator's fingertip to optimally reproduce the tactile sensations experienced by the BioTac. We tested the proposed approach by having eighteen subjects use the augmented da Vinci robot to palpate a heart model with no haptic feedback, only deformation feedback, and deformation plus vibration feedback. Fingertip deformation feedback significantly improved palpation performance by reducing the task completion time, the pressure exerted on the heart model, and the subject's absolute error in detecting the orientation of the embedded plastic stick. Vibration feedback significantly improved palpation performance only for the seven subjects who dragged the BioTac across the model, rather than pressing straight into it
Improving Transparency in Teleoperation by Means of Cutaneous Tactile Force Feedback
No full textA study on the role of cutaneous and kinesthetic force feedback in teleoperation is presented. Cutaneous cues provide less transparency than kinesthetic force, but they do not affect the stability of the teleoperation system. On the other hand, kinesthesia provides a compelling illusion of telepresence but affects the stability of the haptic loop. However, when employing common grounded haptic interfaces, it is not possible to independently control the cutaneous and kinesthetic components of the interaction. For this reason, many control techniques ensure a stable interaction by scaling down both kinesthetic and cutaneous force feedback, even though acting on the cutaneous channel is not necessary.
We discuss here the feasibility of a novel approach. It aims at improving the realism of the haptic rendering, while preserving its stability, by modulating cutaneous force to compensate for a lack of kinesthesia. We carried out two teleoperation experiments, evaluating (1) the role of cutaneous stimuli when reducing kinesthesia and (2) the extent to which an overactuation of the cutaneous channel can fully compensate for a lack of kinesthetic force feedback. Results showed that, to some extent, it is possible to compensate for a lack of kinesthesia with the aforementioned technique, without significant performance degradation. Moreover, users showed a high comfort level in using the proposed system
Cutaneous haptic feedback to ensure the stability of robotic teleoperation systems
No full textCutaneous haptic feedback can be used to enhance the performance of robotic teleoperation systems while guaranteeing their safety. Delivering ungrounded cutaneous cues to the human operator conveys in fact information about the forces exerted at the slave side and does not affect the stability of the control loop. In this work we analyze the feasibility, effectiveness, and implications of providing solely cutaneous feedback in robotic teleoperation. We carried out two peg-in-hole experiments, both in a virtual environment and in a real (teleoperated) environment. Two novel 3-degree-of-freedom fingertip cutaneous displays deliver a suitable amount of cutaneous feedback at the thumb and index fingers. Results assessed the feasibility and effectiveness of the proposed approach. Cutaneous feedback was outperformed by full haptic feedback provided by grounded haptic interfaces, but it outperformed conditions providing no force feedback at all. Moreover, cutaneous feedback always kept the system stable, even in the presence of destabilizing factors such as communication delays and hard contacts
Touch the virtual reality: using the leap motion controller for hand tracking and wearable tactile devices for immersive haptic rendering
No full textThe complexity of the world around us is creating a demand for novel interfaces that will simplify and enhance the way we interact with the environment. The recently unveiled Android Wear operating system addresses this demand by providing a modern system for all those companies that are now developing wearable devices, also known as "wearables". Wearability of robotic devices will enable novel forms of human intention recognition through haptic signals and novel forms of communication between humans and robots. Specifically, wearable haptics will enable devices to communicate with humans during their interaction with the environment they share. Wearable haptic technology have been introduced in our everyday life by Sony. In 1997 its DualShock controller for PlayStation revolutionized the gaming industry by introducing a simple but effective vibrotactile feedback. More recently, Apple unveiled the Apple Watch, which embeds a linear actuator that can make the watch vibrate. It is used whenever the wearer receives an alert or notification, or to communicate with other Apple Watch owners
RemoTouch: A System for Remote Touch Experience
Full text linkThis paper presents some preliminary results on RemoTouch, a system allowing to perform experiences of remote touch. The system consists of an avatar equipped with an instrumented glove and a user wearing tactile displays allowing to feel the remote tactile interaction. The main features of RemoTouch are that it is a wearable system and that a human avatar is used to collect remote tactile interaction data. New paradigms of tactile communication can be designed around the RemoTouch system. Two simple experiences are reported to show the potential of the proposed remote touch architecture
Wearable haptics and hand tracking via an RGB-D camera for immersive tactile experiences
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Teleoperation of steerable flexible needles by combining kinesthetic and vibratory feedback
Full text linkNeedle insertion in soft-tissue is a minimally invasive surgical procedure that demands high accuracy. In this respect, robotic systems with autonomous control algorithms have been exploited as the main tool to achieve high accuracy and reliability. However, for reasons of safety and responsibility, autonomous robotic control is often not desirable. Therefore, it is necessary to focus also on techniques enabling clinicians to directly control the motion of the surgical tools. In this work, we address that challenge and present a novel teleoperated robotic system able to steer flexible needles. The proposed system tracks the position of the needle using an ultrasound imaging system and computes needle’s ideal position and orientation to reach a given target. The master haptic interface then provides the clinician with mixed kinesthetic-vibratory navigation cues to guide the needle toward the computed ideal position and orientation. Twenty participants carried out an experiment of teleoperated needle insertion into a soft-tissue phantom, considering four different experimental conditions. Participants were provided with either mixed kinesthetic-vibratory feedback or mixed kinesthetic-visual feedback. Moreover, we considered two different ways of computing ideal position and orientation of the needle: with or without set-points. Vibratory feedback was found more effective than visual feedback in conveying navigation cues, with a mean targeting error of 0.72 mm when using set-points, and of 1.10 mm without set-points
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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