Results of an Internet survey of myoelectric prosthetic hand users

The results of a survey of 54 persons with upper limb amputations who anonymously completed a questionnaire on an Internet homepage are presented. The survey ran for four years and the participants were divided into groups of females, males, and children. It was found that the most individuals employ their myoelectric hand prosthesis for 8 hours or more. However, the survey also revealed a high level of dissatisfaction with the weight and the grasping speed of the devices. Activities for which prostheses should be useful were stated to include handicrafts, personal hygiene, using cutlery, operation of electronic and domestic devices, and dressing/undressing. Moreover, additional functions, e.g., a force feedback system, independent movements of the thumb, the index finger, and the wrist, and a better glove material are priorities that were identified by the users as being important improvements the users would like to see in myoelectric prostheses.

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Functional benefit of an adaptive myoelectric prosthetic hand compared to a conventional myoelectric hand

Prosthetics and Orthotics International ◽

10.3109/03093649209164305 ◽

1992 ◽

Vol 16 (1) ◽

pp. 32-37 ◽

Cited By ~ 16

Author(s):

K. Bergman ◽

L. Örnholmer ◽

K. Zackrisson ◽

M. Thyberg

Keyword(s):

Upper Limb ◽

Grip Force ◽

Limb Amputation ◽

Prosthetic Hand ◽

Prosthetic Rehabilitation ◽

Myoelectric Prostheses ◽

Upper Limb Amputation ◽

Functional Benefit ◽

Function Test

Eight patients with a traumatic unilateral upper limb amputation, who used conventional myoelectric prostheses, were also fitted with a commercially available myoelectric prosthetic hand with an adaptive grip, in order to compare the functional benefit of the two types of prostheses. Comparisons were made regarding width of grip, force of grip, scores in a standardised grip function test and prosthesis preference. The conventional prosthesis showed significantly better results regarding these parameters. The adaptive hand does not appear to be fully developed for practical use in prosthetic rehabilitation.

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Enhanced visual feedback for slip prevention with a prosthetic hand

Prosthetics and Orthotics International ◽

10.1177/0309364612440077 ◽

2012 ◽

Vol 36 (4) ◽

pp. 423-429 ◽

Cited By ~ 23

Author(s):

Erik D Engeberg ◽

Sanford Meek

Keyword(s):

Visual Feedback ◽

Upper Limb ◽

Grip Force ◽

Force Feedback ◽

Sliding Mode ◽

Controlled Trial ◽

Prosthetic Hand ◽

Success Rates ◽

Precise Control ◽

Visual Force Feedback

Background: 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. Objectives: To determine if the applied grip force from a prosthetic hand can be visually displayed and used to more efficaciously grasp objects. Study Design: Experimental controlled trial. Methods: 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. Results: 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. Conclusions: 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.

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Surface EMG Based Guidance Force Feedback System for Muscle-Specific Upper Limb Training in Stroke Patients

10.1007/978-3-030-70316-5_140 ◽

2021 ◽

pp. 875-881

Author(s):

Sojung Lee ◽

Suncheol Kwon

Keyword(s):

Upper Limb ◽

Force Feedback ◽

Feedback System ◽

Surface Emg ◽

Stroke Patients ◽

Guidance Force

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Design of a 3D-printed hand prosthesis featuring articulated bio-inspired fingers

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411920980889 ◽

2020 ◽

pp. 095441192098088

Author(s):

Juan Sebastian Cuellar ◽

Dick Plettenburg ◽

Amir A Zadpoor ◽

Paul Breedveld ◽

Gerwin Smit

Keyword(s):

3D Printing ◽

Design Principles ◽

Prosthetic Hand ◽

Hand Prosthesis ◽

Fused Deposition ◽

Pinch Force ◽

Actuation System ◽

3D Printed ◽

Energy Dissipated ◽

Dual Material

Various upper-limb prostheses have been designed for 3D printing but only a few of them are based on bio-inspired design principles and many anatomical details are not typically incorporated even though 3D printing offers advantages that facilitate the application of such design principles. We therefore aimed to apply a bio-inspired approach to the design and fabrication of articulated fingers for a new type of 3D printed hand prosthesis that is body-powered and complies with basic user requirements. We first studied the biological structure of human fingers and their movement control mechanisms in order to devise the transmission and actuation system. A number of working principles were established and various simplifications were made to fabricate the hand prosthesis using a fused deposition modelling (FDM) 3D printer with dual material extrusion. We then evaluated the mechanical performance of the prosthetic device by measuring its ability to exert pinch forces and the energy dissipated during each operational cycle. We fabricated our prototypes using three polymeric materials including PLA, TPU, and Nylon. The total weight of the prosthesis was 92 g with a total material cost of 12 US dollars. The energy dissipated during each cycle was 0.380 Nm with a pinch force of ≈16 N corresponding to an input force of 100 N. The hand is actuated by a conventional pulling cable used in BP prostheses. It is connected to a shoulder strap at one end and to the coupling of the whiffle tree mechanism at the other end. The whiffle tree mechanism distributes the force to the four tendons, which bend all fingers simultaneously when pulled. The design described in this manuscript demonstrates several bio-inspired design features and is capable of performing different grasping patterns due to the adaptive grasping provided by the articulated fingers. The pinch force obtained is superior to other fully 3D printed body-powered hand prostheses, but still below that of conventional body powered hand prostheses. We present a 3D printed bio-inspired prosthetic hand that is body-powered and includes all of the following characteristics: adaptive grasping, articulated fingers, and minimized post-printing assembly. Additionally, the low cost and low weight make this prosthetic hand a worthy option mainly in locations where state-of-the-art prosthetic workshops are absent.

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Evaluation of Optimal Vibrotactile Feedback for Force-Controlled Upper Limb Myoelectric Prostheses

Sensors ◽

10.3390/s19235209 ◽

2019 ◽

Vol 19 (23) ◽

pp. 5209 ◽

Cited By ~ 1

Author(s):

Andrea Gonzalez-Rodriguez ◽

Jose L. Ramon ◽

Vicente Morell ◽

Gabriel J. Garcia ◽

Jorge Pomares ◽

...

Keyword(s):

Real Time ◽

Upper Limb ◽

Closed Loop ◽

Fine Tuning ◽

Vibrotactile Feedback ◽

Loop Control ◽

Myoelectric Prostheses ◽

Amplitude Level ◽

Real Time Application ◽

Selection Of

The main goal of this study is to evaluate how to optimally select the best vibrotactile pattern to be used in a closed loop control of upper limb myoelectric prostheses as a feedback of the exerted force. To that end, we assessed both the selection of actuation patterns and the effects of the selection of frequency and amplitude parameters to discriminate between different feedback levels. A single vibrotactile actuator has been used to deliver the vibrations to subjects participating in the experiments. The results show no difference between pattern shapes in terms of feedback perception. Similarly, changes in amplitude level do not reflect significant improvement compared to changes in frequency. However, decreasing the number of feedback levels increases the accuracy of feedback perception and subject-specific variations are high for particular participants, showing that a fine-tuning of the parameters is necessary in a real-time application to upper limb prosthetics. In future works, the effects of training, location, and number of actuators will be assessed. This optimized selection will be tested in a real-time proportional myocontrol of a prosthetic hand.

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Human Hand Anatomy-Based Prosthetic Hand

Sensors ◽

10.3390/s21010137 ◽

2020 ◽

Vol 21 (1) ◽

pp. 137

Author(s):

Larisa Dunai ◽

Martin Novak ◽

Carmen García Espert

Keyword(s):

3D Printing ◽

Degrees Of Freedom ◽

Use Of Force ◽

Hand Movements ◽

Human Hand ◽

Prosthetic Hand ◽

Object Surface ◽

Hand Phalanges ◽

High Level

The present paper describes the development of a prosthetic hand based on human hand anatomy. The hand phalanges are printed with 3D printing with Polylactic Acid material. One of the main contributions is the investigation on the prosthetic hand joins; the proposed design enables one to create personalized joins that provide the prosthetic hand a high level of movement by increasing the degrees of freedom of the fingers. Moreover, the driven wire tendons show a progressive grasping movement, being the friction of the tendons with the phalanges very low. Another important point is the use of force sensitive resistors (FSR) for simulating the hand touch pressure. These are used for the grasping stop simulating touch pressure of the fingers. Surface Electromyogram (EMG) sensors allow the user to control the prosthetic hand-grasping start. Their use may provide the prosthetic hand the possibility of the classification of the hand movements. The practical results included in the paper prove the importance of the soft joins for the object manipulation and to get adapted to the object surface. Finally, the force sensitive sensors allow the prosthesis to actuate more naturally by adding conditions and classifications to the Electromyogram sensor.

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Development and Testing of a Methodology for the Assessment of Acceptability of LKA Systems

Machines ◽

10.3390/machines8030047 ◽

2020 ◽

Vol 8 (3) ◽

pp. 47 ◽

Cited By ~ 1

Author(s):

Luca Salvati ◽

Matteo d’Amore ◽

Anita Fiorentino ◽

Arcangelo Pellegrino ◽

Pasquale Sena ◽

...

Keyword(s):

Force Feedback ◽

Feedback System ◽

Operating Conditions ◽

Experimental Methodology ◽

Driving Safety ◽

Steering Wheel ◽

Human In The Loop ◽

Automation Systems ◽

Driving Stability ◽

Lane Keeping

In recent years, driving simulators have been widely used by automotive manufacturers and researchers in human-in-the-loop experiments, because they can reduce time and prototyping costs, and provide unlimited parametrization, more safety, and higher repeatability. Simulators play an important role in studies about driver behavior in operating conditions or with unstable vehicles. The aim of the research is to study the effects that the force feedback (f.f.b.), provided to steering wheel by a lane-keeping-assist (LKA) system, has on a driver’s response in simulators. The steering’s force feedback system is tested by reproducing the conditions of criticality of the LKA system in order to minimize the distance required to recover the driving stability as a function of set f.f.b. intensity and speed. The results, obtained in three specific criticality conditions, show that the behaviour of the LKA system, reproduced in the simulator, is not immediately understood by the driver and, sometimes, it is in opposition with the interventions performed by the driver to ensure driving safety. The results also compare the performance of the subjects, either overall and classified into subgroups, with reference to the perception of the LKA system, evaluated by means of a questionnaire. The proposed experimental methodology is to be regarded as a contribution for the integration of acceptance tests in the evaluation of automation systems.

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