Haptic proprioception in a virtual locomotor task

Karunakaran, Kiran K.; Abbruzzese, Kevin; Xu, Hao; Ehrenberg, Naphtaly; Foulds, Richard

doi:10.1109/embc.2014.6944400

Cited by 6 publications

(6 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…That study included 18 subjects controlling virtual feet using hand movements to produce gait trajectories in a virtual environment. Our results indicated that users, provided with haptic through a physical link, and visual feedback (both sensations felt by the hands and visual observation), produced hand and virtual foot trajectories similar to biological gait trajectories (Karunakaran et al, 2014(Karunakaran et al, , 2017. We showed that for this to be a viable exoskeleton control method, the hands must be haptically connected either contralaterally or ipsilaterally to the feet.…”

Section: Introductionmentioning

confidence: 68%

“…Similar to those efforts, the long-term objective of our work is to allow users to intuitively express their desired gait kinematics and dynamics using their arms and hands as sensory and motor alternatives to their legs and feet. Our prior lower extremity research (Karunakaran et al, 2014(Karunakaran et al, , 2017 evaluated the feedback conditions required by the hand to produce gait kinematics. That study included 18 subjects controlling virtual feet using hand movements to produce gait trajectories in a virtual environment.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A Novel User Control for Lower Extremity Rehabilitation Exoskeletons

et al. 2020

Self Cite

View full text Add to dashboard Cite

Lower extremity exoskeletons offer the potential to restore ambulation to individuals with paraplegia due to spinal cord injury. However, they often rely on preprogrammed gait, initiated by switches, sensors, and/or EEG triggers. Users can exercise only limited independent control over the trajectory of the feet, the speed of walking, and the placement of feet to avoid obstacles. In this paper, we introduce and evaluate a novel approach that naturally decodes a neuromuscular surrogate for a user's neutrally planned foot control, uses the exoskeleton's motors to move the user's legs in real-time, and provides sensory feedback to the user allowing real-time sensation and path correction resulting in gait similar to biological ambulation. Users express their desired gait by applying Cartesian forces via their hands to rigid trekking poles that are connected to the exoskeleton feet through multi-axis force sensors. Using admittance control, the forces applied by the hands are converted into desired foot positions, every 10 milliseconds (ms), to which the exoskeleton is moved by its motors. As the trekking poles reflect the resulting foot movement, users receive sensory feedback of foot kinematics and ground contact that allows on-the-fly force corrections to maintain the desired foot behavior. We present preliminary results showing that our novel control can allow users to produce biologically similar exoskeleton gait.

show abstract

Section: Introductionmentioning

confidence: 68%

Section: Introductionmentioning

confidence: 99%

A Novel User Control for Lower Extremity Rehabilitation Exoskeletons

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Studies have shown that teleoperation is effective in applications for upper-limb prostheses [32], in robot-assisted surgical systems [33], [34], and for rehabilitation, with information crossing between limbs [35]. Teleoperation of lower-limb exoskeletons has been investigated, but only in a virtual environment [36]. We propose to use a wrist exoskeleton to both teleoperate and receive sensory feedback about the state of a prosthetic ankle while walking ( Figure 1).…”

Section: Introductionmentioning

confidence: 99%

Teleoperation of an ankle-foot prosthesis with a wrist exoskeleton

Welker

Chiu

Voloshina

et al. 2020

Preprint

View full text Add to dashboard Cite

Objective: We aimed to develop a system for people with amputation that non-invasively restores missing control and sensory information for an ankle-foot prosthesis. Methods: In our approach, a wrist exoskeleton allows people with amputation to control and receive feedback from their prosthetic ankle via teleoperation. We implemented a position control scheme and torque control scheme, both of which provide haptic feedback at the wrist. We also investigated two low-level position controllers, and measured tracking error and frequency response for each system component. To demonstrate feasibility and evaluate system performance, we conducted an experiment in which one participant with a transtibial amputation tracked desired wrist trajectories during walking, while we measured wrist and ankle response. Results: Benchtop testing demonstrated that for relevant walking frequencies, system error was below human perception error. During the walking experiment, the participant was able to voluntarily follow different wrist trajectories with an average RMS error of 1.55° after training. A position control scheme using feedforward control with iterative learning and haptic feedback at the wrist resulted in the most accurate ankle tracking (RMS error = 0.8°). The torque control scheme achieved an ankle torque RMS error of 8.3 N·m. Conclusion: We present a system that allows a user with amputation to control an ankle-foot prosthesis and receive feedback about its state using a wrist exoskeleton with accuracy comparable to biological neuromotor control. Significance: This bilateral teleoperation system enables novel prosthesis control and feedback strategies that could result in improved prosthesis control and aid motor learning.

show abstract

“…Only a few studies have investigated the application of sensory feedback in wearable exoskeletons [ 25 – 28 ]. And only in the study of De Castro [ 27 ], a limited number of SCI subjects were involved, who could use the feedback and walk without continuously looking at their legs.…”

Section: Introductionmentioning

confidence: 99%

“…And only in the study of De Castro [ 27 ], a limited number of SCI subjects were involved, who could use the feedback and walk without continuously looking at their legs. Similar to the lower-limb prostheses, the stimulation methods in the various studies varied (pressure cuff [ 25 ], electrostimulation [ 26 , 27 ] or haptic force feedback [ 28 ]) as well as the feedback parameters (knee torque [ 25 ], knee angle [ 25 ], hip angle [ 26 ], swing phase [ 27 ] and force under the feet [ 28 ]). There is a clear need for sensory feedback in wearable exoskeletons, but it is not clear which stimulation methods and which feedback parameters should be used.…”

Section: Introductionmentioning

confidence: 99%

Questionnaire results of user experiences with wearable exoskeletons and their preferences for sensory feedback

Muijzer-Witteveen

Sibum

Dijsseldonk

et al. 2018

J NeuroEngineering Rehabil

View full text Add to dashboard Cite

BackgroundWearable exoskeletons can be a powerful tool for the facilitation of ambulation of complete Spinal Cord Injury (SCI) subjects, which has several psychological and physical advantages. However, exoskeleton control is difficult for this group of users and requires a long period of training. People with SCI not only lack the motor control, but also miss the sensory information from below the level of the lesion, which is for example very important in their perception of body posture and makes balancing with an exoskeleton difficult.It is hypothesized that through sensory substitution part of the missing sensory information can be provided and might thereby improve the control of an exoskeleton. However, it is not known which information would be most important to receive while using an exoskeleton and how this feedback should be provided.MethodsTo investigate the preferences of users of an exoskeleton, a questionnaire was filled out by 10 SCI subjects who underwent a training program with a commercial exoskeleton (ReWalk).The questionnaire consisted of questions about the use of the exoskeleton to identify which information is missing and which instructions from the therapists were needed to be able to control the exoskeleton. The second part of the questionnaire focused on the possibilities of sensory feedback and preferences for stimulation methods (auditory, vibrotactile or visual) and feedback timing (discrete or continuous) were investigated. Furthermore, six options for feedback parameters (step initiation, continuous and discrete gait phases, foot position and mediolateral and anteroposterior weight shift) were proposed and the respondents were asked to indicate their preferences.ResultsThree feedback parameters (feedback about mediolateral and anteroposterior weight shift and feedback about step initiation) were considered as possibly helpful by the respondents. Furthermore, there were slight preferences for the use of vibrotactile (over auditory and visual) and discrete (over continuous) feedback.ConclusionsThe answers of the respondents on the optimal feedback parameters were rather variable and therefore it is recommended to let the users choose their preferred feedback system during a training session with several feedback options. However, there are slight preferences for the use of vibrotactile stimulation provided in a discrete way.Electronic supplementary materialThe online version of this article (10.1186/s12984-018-0445-0) contains supplementary material, which is available to authorized users.

show abstract

Haptic proprioception in a virtual locomotor task

Cited by 6 publications

References 11 publications

A Novel User Control for Lower Extremity Rehabilitation Exoskeletons

A Novel User Control for Lower Extremity Rehabilitation Exoskeletons

Teleoperation of an ankle-foot prosthesis with a wrist exoskeleton

Questionnaire results of user experiences with wearable exoskeletons and their preferences for sensory feedback

Contact Info

Product

Resources

About