Congestion Control for Network-Aware Telehaptic Communication

Telehaptic applications involve delay-sensitive multimedia communication between remote locations with distinct Quality of Service (QoS) requirements for different media components. These QoS constraints pose a variety of challenges, especially when the communication occurs over a shared network, with unknown and time-varying cross-traffic. In this work, we propose a transport layer congestion control protocol for telehaptic applications operating over shared networks, termed as dynamic packetization module (DPM). DPM is a lossless, network-aware protocol which tunes the telehaptic packetization rate based on the level of congestion in the network. To monitor the network congestion, we devise a novel network feedback module, which communicates the end-to-end delays encountered by the telehaptic packets to the respective transmitters with negligible overhead. Via extensive simulations, we show that DPM meets the QoS requirements of telehaptic applications over a wide range of network cross-traffic conditions. We also report qualitative results of a real-time telepottery experiment with several human subjects, which reveal that DPM preserves the quality of telehaptic activity even under heavily congested network scenarios. Finally, we compare the performance of DPM with several previously proposed telehaptic communication protocols and demonstrate that DPM outperforms these protocols.Comment: 25 pages, 19 figure

Perception of delay in haptic telepresence systems

Time delay is recognized as an important issue in haptic telepresence systems as it is inherent to long-distance data transmission. What factors influence haptic delay perception in a time-delayed environment are, however, largely unknown. In this article, we examine the impact of manual movement frequency and amplitude in a sinusoidal exploratory movement as well as the stiffness of the haptic environment on the detection threshold for delay in haptic feedback. The results suggest that the detection of delay in force feedback depends on the movement frequency and amplitude, while variation of the absolute feedback force level does not influence the detection threshold. A model based on the exploration movement is proposed and guidelines for system design with respect to the time delay in haptic feedback are provided

Temporal perception of visual-haptic events in multimodal telepresence system

Book synopsis: Haptic interfaces are divided into two main categories: force feedback and tactile. Force feedback interfaces are used to explore and modify remote/virtual objects in three physical dimensions in applications including computer-aided design, computer-assisted surgery, and computer-aided assembly. Tactile interfaces deal with surface properties such as roughness, smoothness, and temperature. Haptic research is intrinsically multi-disciplinary, incorporating computer science/engineering, control, robotics, psychophysics, and human motor control. By extending the scope of research in haptics, advances can be achieved in existing applications such as computer-aided design (CAD), tele-surgery, rehabilitation, scientific visualization, robot-assisted surgery, authentication, and graphical user interfaces (GUI), to name a few. Advances in Haptics presents a number of recent contributions to the field of haptics. Authors from around the world present the results of their research on various issues in the field of haptics

Sensory Manipulation as a Countermeasure to Robot Teleoperation Delays: System and Evidence

In the field of robotics, robot teleoperation for remote or hazardous environments has become increasingly vital. A major challenge is the lag between command and action, negatively affecting operator awareness, performance, and mental strain. Even with advanced technology, mitigating these delays, especially in long-distance operations, remains challenging. Current solutions largely focus on machine-based adjustments. Yet, there's a gap in using human perceptions to improve the teleoperation experience. This paper presents a unique method of sensory manipulation to help humans adapt to such delays. Drawing from motor learning principles, it suggests that modifying sensory stimuli can lessen the perception of these delays. Instead of introducing new skills, the approach uses existing motor coordination knowledge. The aim is to minimize the need for extensive training or complex automation. A study with 41 participants explored the effects of altered haptic cues in delayed teleoperations. These cues were sourced from advanced physics engines and robot sensors. Results highlighted benefits like reduced task time and improved perceptions of visual delays. Real-time haptic feedback significantly contributed to reduced mental strain and increased confidence. This research emphasizes human adaptation as a key element in robot teleoperation, advocating for improved teleoperation efficiency via swift human adaptation, rather than solely optimizing robots for delay adjustment.Comment: Submitted to Scientific Report

Delayed action does not always require the ventral stream : A study on a patient with visual form agnosia

Acknowledgements The authors would like to thank D.F. for participating in all our experiments with great patience. We also would like to thank Dr David Carey for his very helpful and insightful comments on an earlier draft of this manuscript. This work was partly funded by a post-doctoral research fellowship awarded to Constanze Hesse by the German Research Council (DFG/HE 6011/1-1).Peer reviewedPostprin

Method to Estimate Human Inattention in Teleoperation of Mobile Robots

In teleoperation of mobile robots the operator is remotely located. As a result, generally the human perception of the remote environment is distorted affecting the mission negatively. Visual information can be degraded because of video images bandwith, time lags, frame rates, point of view and motion effects among other reasons. Although many researchers have proposed a variety of methods for measuring perception, just a few can be used in control closed loop systems. This paper aims to provide a novel metric to the human visual inattention upon risk for a remotely navigated mobile robot. We present both qualitative and quantitative guidelines for designing the metric in a teleoperation of a mobile robot. The method allows to incorporate the metric in a control closed loop system, and task consists in guiding the robot from an initial point to a final one as quick as possible, considering the constraint of avoiding collisions. Furthermore, a haptic cue based on the metric is proposed in order to help the human to avoid collisions. A system stability analysis considering time varying delays is proposed. Additionally, we present a human in the loop experiment of a teleoperation of a 3D mobile robot simulator in order to remark the advantages of using human factors in the controller.Fil: Penizzotto Bacha, Franco Victor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: Mut, Vicente Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: Slawiñski, Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; Argentin