Stiffness perception during pinching and dissection with teleoperated haptic forceps

We routinely have physical interactions with others, whether it be handing someone a glass of water or jointly moving a heavy object together. These sensorimotor interactions between humans typically rely on visual feedback and haptic feedback. Recent single-participant studies have highlighted that the unique noise and time delays of each sense must be considered to estimate the state, such as the position and velocity, of one's own movement. However, we know little about how visual feedback and haptic feedback are used to estimate the state of another person. Here, we tested how humans utilize visual feedback and haptic feedback to estimate the state of their partner during a collaborative sensorimotor task. Across two experiments, we show that visual feedback dominated haptic feedback during collaboration. Specifically, we found that visual feedback led to comparatively lower task-relevant movement variability, smoother collaborative movements, and faster trial completion times. We also developed an optimal feedback controller that considered the noise and time delays of both visual feedback and haptic feedback to estimate the state of a partner. This model was able to capture both lower task-relevant movement variability and smoother collaborative movements. Taken together, our empirical and modeling results support the idea that visual accuracy is more important than haptic speed to perform state estimation of a partner during collaboration.NEW & NOTEWORTHY Physical collaboration between two or more individuals involves both visual and haptic feedback. Here, we investigated how visual and haptic feedback is used to estimate the movements of a partner during a collaboration task. Our experimental and computational modeling results parsimoniously support the notion that greater visual accuracy is more important than faster yet noisier haptic feedback when estimating the state of a partner.

This research evaluated visual and haptic feedback for enhancing operator situational awareness during multitasking drone operations, investigating how task complexity influenced feedback effectiveness. Two virtual reality experiments were conducted: Study 1 assessed three types of visual feedback (Static, Blink, and Shake), while Study 2 compared visual, haptic, and visual-haptic multimodal feedback across varying task complexity levels determined by target density. Participants performed drone operation tasks requiring simultaneous obstacle avoidance and target counting. Results revealed that dynamic visual feedback (Shake) significantly improved primary task accuracy, reduced cognitive load, and was the preferred visual feedback type. Furthermore, haptic and visual-haptic feedback significantly shortened obstacle avoidance reaction times and decreased cognitive workload compared to visual feedback. Task complexity proved to be a critical factor: while visual feedback sufficed for low complexity scenarios, visual-haptic feedback offered distinct advantages in medium and high complexity tasks, providing insights for complexity-responsive drone interface design.

In this paper, we present a study that evaluates the effect of visual and haptic feedbacks and their relevance to human performance in a needle insertion task. A virtual needle insertion simulator with a four-layer tissue model (skin, fat, muscle, and bone) and haptic feedback is used for perceptual experiments. The task was to detect the puncture of a particular layer using haptic and visual cues provided by the simulation. The results show that the addition of force feedback reduces error in detection of transitions between tissue layers by at least 55%. The addition of real-time visual feedback (image overlay) improved user performance by at least 87% in scenarios without force feedback. Presentation of both force and visual feedback improved performance by at least 43% in comparison to scenarios without feedback. These results suggest that real-time image overlay provides greater improvement in performance than force feedback.

This chapter examines the use of haptic feedback in a multimedia simulation as a means of conveying information about physical science concepts. The case study presented herein investigates the effects of force feedback on children’s conceptions of gravity, mass, and related concepts following experimentation with a force-feedback-enabled simulation. Two groups of 17 children conducted experiments with the simulation; the experimental group used both visual and force feedback, and the control group used visual feedback only. Evidence of positive gains by the experimental group who used the simulation with force feedback is presented. Guidelines for applying these technologies effectively for educational purposes are discussed. This chapter adds to the limited research on the application of haptic feedback for conceptual learning and provides a basis for further research into the effects of computer-based haptic feedback on children’s cognition.

For educational purposes, virtual reality (VR) is often used to produce life-like experiences. However, the use of haptic feedback in educational practices for science and mathematics remained under-studied. Haptically-enabled science simulations (HESSs) enable students to physically experience the concepts being taught via haptic feedback. We present a study on the effect of a buoyancy HESS designed to aid in the understanding of basic physics concepts. We hypothesize that introducing both visual and haptic feedback of the underlying simulated forces will improve participants understanding. We investigate this hypothesis with a 2 (haptics: yes, no) × 2 (visuals: yes, no) between subjects design user study, where all participants were randomly assigned to one of the four conditions. Participants were given a pretest of buoyancy knowledge, then instructed to interact with the buoyancy simulation, then given a post-test of buoyancy knowledge. The present study is still in the process of data collection, with 40 out of 60 participants. Preliminary results highlight a significant improvement in performance of participants in the haptic-and-visual condition, while no significant differences were observed in other conditions.

Most prosthetic hand users are limited to visual feedback of movement performance. To characterize the benefit of vibrotactile feedback for a task that lacks haptic feedback, a virtual environment was used to experimentally manipulate visual, task-relevant haptic, and remote vibrotactile feedback on simple object manipulation for unimpaired subjects. The combination of visual and remote vibrotactile feedback was compared to visual feedback alone, and to simultaneous visual and direct haptic feedback to represent ideal performance. Visual and vibrotactile feedback resulted in improvement of most performance variables including difficulty ratings relative to visual feedback alone. However addition of sensory cues to visual feedback increased trial times and the increase was steeper for vibrotactile than for haptic feedback. Specifically, during vibrotactile feedback the velocity did not change, but the duration of execution increased due to improved performance, resulting in increased trial times. This result suggests future exploration of performance improvement and execution speed for augmented sensory feedback.

The focus of this research is on the perception and control of forces produced by the hand. It is known that the change in force that subjects can reliably discriminate is approximately 6%, and that subjects are able to match forces generated by two corresponding muscle groups with an accuracy of approximately 15%. The present study was concerned with measuring the ability to control finger force using only haptic feedback and both haptic and visual feedback. It was found that subjects were surprising good at controlling forces for up to 120 s using only haptic feedback with mean absolute errors of less than 0.3 N over a force range of 2–6 N. The variation in force averaged 10.5% when haptic feedback was available and decreased to 6% when visual feedback was also provided. These results provide a framework for specifying the characteristics of force-reflecting haptic interfaces that should optimize human perception.

Camera drones allow exploring remote scenes that are inaccessible or inappropriate to visit in person. However, these exploration experiences are often limited due to insufficient scene information provided by front cameras, where only 2D images or videos are supplied. Combining a camera drone vision with haptic feedback would augment users' spatial understandings of the remote environment. But such designs are usually difficult for users to learn and apply, due to the complexity of the system and unfluent UAV control. In this paper, we present a new telepresence system for remote environment exploration, with a drone agent controlled by a VR mid-air panel. The drone is capable of generating real-time location and landmark details using integrated Simultaneous Location and Mapping (SLAM). The SLAMs' point cloud generations are produced using RGB input, and the results are passed to a Generative Adversarial Network (GAN) to reconstruct 3D remote scenes in real-time. The reconstructed objects are taken advantage of by haptic devices which could improve user experience through haptic rendering. Capable of providing both visual and haptic feedback, our system allows users to examine and exploit remote areas without having to be physically present. An experiment has been conducted to verify the usability of 3D reconstruction result in haptic feedback rendering.

Controlling the motion of a prosthetic upper limb without visual feedback is extremely difficult because the wearer does not know the prosthesis' configuration. This paper describes an experiment designed to determine the relative importance of visual and haptic position feedback during targeted force-based motion by non-amputee human subjects as an analogy to prosthetic use. Subjects control the angle of a virtual proxy through an admittance relationship by generating torque at the MCP joint of the right index finger. During successive repetitions of a target acquisition task, the proxy's state is selectively conveyed to the user through graphical display, finger motion, and tactile stimulation. Performance metrics for each feedback condition will provide insights on the role of haptic position feedback and may help guide the development of future upper-limb prostheses

The perceptual deadband (PD) data reduction scheme allows for a significant reduction of network load in real-time haptic communication scenarios. Aiming to ascertain how the optimum PD data reduction parameter k is best determined, an experiment was conducted in which a possible interaction of PD data reduction and visual feedback on haptic feedback quality and task performance was investigated. The results show that when haptic feedback is complemented with visual feedback, haptic data reduction affects haptic feedback quality at a lower data reduction rate than it affects task performance. When visual feedback is missing, however, this effect is reversed. These results imply that the perception of haptic feedback quality is markedly influenced by visual sensory input as well as task requirements; hence, it is recommended to consider feedback quality and task performance in the optimization of PD reduction before such schemes may be applied to industrial telepresence and teleaction systems.

The ability to control index finger and elbow flexion forces was measured while subjects used either haptic feedback or both haptic and visual feedback to control the forces exerted. Over a 120-s time period subjects were able to control the finger forces ranging from 2 to 6 N to within 1 N using only haptic feedback, and elbow flexion forces to within 4.5 N over a force range of 10-30 N. At the same force amplitude there was no significant difference between the two muscle groups in the precision or accuracy with which the force could be controlled, suggesting that there is not a proximal to distal gradient in force control as has been found for the control of limb movement and position.

PurposeHaptic feedback could improve the efficiency of needle insertion procedures by providing surgeons with enhanced sensing and guiding capabilities. A framework has been developed to provide physicians with enhanced haptic feedback during CT-guided needle insertion procedures in oncology.MethodsThe physicians encountered needle-tissue interaction and guidance forces with visual feedback to accurately reach the tumor. The force feedback to users was enhanced by amplifying several parameters in the feedback model, such as tip forces and radial forces. The study evaluated the effect of multiple haptic and visual feedback algorithms on user performance in efficiently inserting the needle. In this experimental pilot study, 12 participants including three interventional radiologists engaged in five experimental scenarios simulating a needle insertion.ResultsThe results showed that enhanced force feedback for tumor perception reduced tumor targeting error and trajectory deviation, compared to natural force feedback. This was also the case when tumor perception and haptic guidance were both enhanced. Additionally, real-time visual feedback and enhanced force feedback for guidance reduced the duration to finish the task significantly. Participants still preferred real-time visual feedback over enhanced haptic feedback cues.ConclusionsOn average, small tumors (around 3mm in diameter) can be successfully targeted with enhanced haptic feedback in the radial and axial directions. Additionally, critical regions, such as veins within the liver, can be avoided more effectively as users maintain the desired trajectory with greater accuracy.

Stand-alone virtual environments (VEs) using haptic devices have proved useful for assembly/disassembly simulation of mechanical components. Nowadays, collaborative haptic virtual environments (CHVEs) are also emerging. A new peer-to-peer collaborative haptic assembly simulator (CHAS) has been developed whereby two users can simultaneously carry out assembly tasks using haptic devices. Two major challenges have been addressed: virtual scene synchronization (consistency) and the provision of a reliable and effective haptic feedback. A consistency-maintenance scheme has been designed to solve the challenge of achieving consistency. Results show that consistency is guaranteed. Furthermore, a force-smoothing algorithm has been developed which is shown to improve the quality of force feedback under adverse network conditions. A range of laboratory experiments and several real trials between Labein (Spain) and Queen's University Belfast (Northern Ireland) have verified that CHAS can provide an adequate haptic interaction when both users perform remote assemblies (assembly of one user's object with an object grasped by the other user). Moreover, when collisions between grasped objects occur (dependent collisions), the haptic feedback usually provides satisfactory haptic perception. Based on a qualitative study, it is shown that the haptic feedback obtained during remote assemblies with dependent collisions can continue to improve the sense of co-presence between users with regard to only visual feedback.

Upper limb amputees have no direct sense of the grip force applied by a prosthetic hand; thus, precise control of the applied grip force is difficult for amputees. Since there is little object deformation when rigid objects are grasped, it is difficult for amputees to visually gauge the applied grip force in this situation. To determine if the applied grip force from a prosthetic hand can be visually displayed and used to more efficaciously grasp objects. Experimental controlled trial. Force feedback is used in the control algorithm for the prosthetic hand and supplied visually to the user through a bicolor LED experimentally mounted to the thumb. Several experiments are performed by able-bodied test subjects to rate the usefulness of the additional visual feedback when manipulating a clearly visible, brittle object that can break if grasped too firmly. A hybrid force-velocity sliding mode controller is used with and without additional visual force feedback supplied to the operators. Subjective evaluations and success rates from the test subjects indicate a statistically significant reduction in breaking the grasped object when using the prosthesis with the extra visual feedback. The additional visual force feedback can effectively facilitate the manipulation of brittle objects. Clinical relevance The novel approach of this research is the implementation of a noninvasive, effective and economic technique to visually indicate the grip force applied by a prosthetic hand to upper limb amputees. This technique provides a statistically significant improvement when handling brittle objects.

Virtual reality can help to learn basic laparoscopic tasks. However, no haptic feedback, which alerts for tissue slippage, is provided by most simulators, although, it might be of influence for the decrease of errors. This study explored whether visual or tactile feedback can be used to alert the surgeon of tissue slippage. Twenty-four participants performed a laparoscopic grasping task and where provided with either visual or tactile feedback about tissue slippage. The reaction time with the visual feedback was compared to the reaction time with tactile feedback signal. The results showed that when tissue slippage is simulated, tactile feedback shows significant faster reaction times (269ms) than visual feedback signals (398ms).