Computational approaches to decode grasping force and velocity level in upper limb amputee from intraneural peripheral signals

There are several opensource or commercially available software platforms widely used for the development of dynamic simulations of movement. While computational approaches to calculating the dynamics of a musculoskeletal model are conceptually similar across platforms, differences in implementation may influence simulation output. To understand predictions made using simulation, it is important to understand differences that may result from the choice of model or platform. Our aims were to 1) develop a musculoskeletal model of the upper limb suitable for dynamic simulation and 2) evaluate the influence of the choice between SIMM-SD/Fast and OpenSim simulation platforms on gravity- and EMG-driven simulations of movement.

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Vibrotactile grasping force and hand aperture feedback for myoelectric forearm prosthesis users

Prosthetics and Orthotics International ◽

10.1177/0309364614522260 ◽

2014 ◽

Vol 39 (3) ◽

pp. 204-212 ◽

Cited By ~ 37

Author(s):

Heidi JB Witteveen ◽

Hans S Rietman ◽

Peter H Veltink

Keyword(s):

Upper Limb ◽

Force Feedback ◽

Feedback Condition ◽

Limb Loss ◽

Vibrotactile Stimulation ◽

Vibrotactile Feedback ◽

Task Durations ◽

Grasping Force ◽

Additional Value ◽

Virtual Grasping

Background: User feedback about grasping force and hand aperture is very important in object handling with myoelectric forearm prostheses but is lacking in current prostheses. Vibrotactile feedback increases the performance of healthy subjects in virtual grasping tasks, but no extensive validation on potential users has been performed. Objectives: Investigate the performance of upper-limb loss subjects in grasping tasks with vibrotactile stimulation, providing hand aperture, and grasping force feedback. Study design: Cross-over trial. Methods: A total of 10 subjects with upper-limb loss performed virtual grasping tasks while perceiving vibrotactile feedback. Hand aperture feedback was provided through an array of coin motors and grasping force feedback through a single miniature stimulator or an array of coin motors. Objects with varying sizes and weights had to be grasped by a virtual hand. Results: Percentages correctly applied hand apertures and correct grasping force levels were all higher for the vibrotactile feedback condition compared to the no-feedback condition. With visual feedback, the results were always better compared to the vibrotactile feedback condition. Task durations were comparable for all feedback conditions. Conclusion: Vibrotactile grasping force and hand aperture feedback improves grasping performance of subjects with upper-limb loss. However, it should be investigated whether this is of additional value in daily-life tasks. Clinical relevance This study is a first step toward the implementation of sensory vibrotactile feedback for users of myoelectric forearm prostheses. Grasping force feedback is crucial for optimal object handling, and hand aperture feedback is essential for reduction of required visual attention. Grasping performance with feedback is evaluated for the potential users.

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Survey on Main Drive Methods Used in Humanoid Robotic Upper Limbs

Cyborg and Bionic Systems ◽

10.34133/2021/9817487 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Yiwei Wang ◽

Wenyang Li ◽

Shunta Togo ◽

Hiroshi Yokoi ◽

Yinlai Jiang

Keyword(s):

Upper Limb ◽

Structural Features ◽

Drive System ◽

Robotic Hand ◽

Light Weight ◽

Upper Limbs ◽

Factors Affecting ◽

Advantages And Disadvantages ◽

Grasping Force ◽

Tendon Drive

Humanoid robotic upper limbs including the robotic hand and robotic arm are widely studied as the important parts of a humanoid robot. A robotic upper limb with light weight and high output can perform more tasks. The drive system is one of the main factors affecting the weight and output of the robotic upper limb, and therefore, the main purpose of this study is to compare and analyze the effects of the different drive methods on the overall structure. In this paper, we first introduce the advantages and disadvantages of the main drive methods such as tendon, gear, link, fluid (hydraulic and pneumatic), belt, chain, and screw drives. The design of the drive system is an essential factor to allow the humanoid robotic upper limb to exhibit the structural features and functions of the human upper limb. Therefore, the specific applications of each drive method on the humanoid robotic limbs are illustrated and briefly analyzed. Meanwhile, we compared the differences in the weight and payload (or grasping force) of the robotic hands and robotic arms with different drive methods. The results showed that the tendon drive system is easier to achieve light weight due to its simple structure, while the gear drive system can achieve a larger torque ratio, which results in a larger output torque. Further, the weight of the actuator accounts for a larger proportion of the total weight, and a reasonable external placement of the actuator is also beneficial to achieve light weight.

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Reflex Responses in Upper Limb Muscles to Cutaneous Stimuli

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100048174 ◽

1993 ◽

Vol 20 (04) ◽

pp. 271-278 ◽

Cited By ~ 30

Author(s):

R. Chen

Keyword(s):

Stimulus Intensity ◽

Upper Limb ◽

Healthy Subjects ◽

Voluntary Contraction ◽

Cutaneous Reflexes ◽

Focal Lesions ◽

Normal Ranges ◽

Conduction Velocities ◽

Limb Muscles ◽

Biphasic Responses

ABSTRACT:Cutaneous reflexes in the upper limb were elicited by stimulating digital nerves and recorded by averaging rectified EMG from proximal and distal upper limb muscles during voluntary contraction. Distal muscles often showed a triphasic response: an inhibition with onset about 50 ms (Il) followed by a facilitation with onset about 60 ms (E2) followed by another inhibition with onset about 80 ms (12). Proximal muscles generally showed biphasic responses beginning with facilitation or inhibition with onset at about 40 ms. Normal ranges for the amplitude of these components were established from recordings on 22 arms of 11 healthy subjects. An attempt was made to determine the alterent fibers responsible for the various components by varying the stimulus intensity, by causing ischemic block of larger fibers and by estimating the afferent conduction velocities. The central pathways mediating these reflexes were examined by estimating central delays and by studying patients with focal lesions

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