scholarly journals Human-Inspired Reflex to Autonomously Prevent Slip of Grasped Objects Rotated with a Prosthetic Hand

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Zachary Ray ◽  
Erik D. Engeberg
Keyword(s):  
Grip Force ◽  
Performance Metrics ◽  
Human Subjects ◽  
Sorting Task ◽  
Prosthetic Hand ◽  
The Novel ◽  
Prosthetic Hands ◽  
Cognitive Distraction ◽  
Human Experiments ◽  
Object Sorting

Autonomously preventing grasped objects from slipping out of prosthetic hands is an important feature for limb-absent people since they cannot directly feel the grip force applied to grasped objects. Oftentimes, a satisfactory grip force in one situation will be inadequate in different situations, such as when the object is rotated or transported. Over time, people develop a grip reflex to prevent slip of grasped objects when they are rotated with respect to gravity by their natural hands. However, this reflexive trait is absent in commercially available prosthetic hands. This paper explores a human-inspired grasp reflex controller for prosthetic hands to prevent slip of objects when they are rotated. This novel human-inspired grasped object slip prevention controller is evaluated with 6 different objects in benchtop tests and by 12 able-bodied subjects during human experiments replicating realistic tasks of daily life. An analysis of variance showed highly significant improvement in the number of successfully completed cycles for both the benchtop and human tests when the slip prevention reflex was active. An object sorting task, which was designed to serve as a cognitive distraction for the human subjects while controlling the prosthetic hand, had a significant impact on many of the performance metrics. However, assistance from the novel slip prevention reflex mitigated the effects of the distraction, offering an effective method for reducing both object slip and the required cognitive load from the prosthetic hand user.

Design of a Motor-Driven Mechanism to Conduct Experiments to Determine the Passive Joint Properties of the Human Index Finger

2011 ◽  
Author(s):  
Pei-Hsin Kuo ◽  
Jerod Hayes ◽  
Ashish D. Deshpande
Keyword(s):  
Index Finger ◽  
Human Subjects ◽  
Human Hand ◽  
The Novel ◽  
Prosthetic Hands ◽  
Joint Properties ◽  
Driven System ◽  
New Generation ◽  
Novel Design

Our long term goal is to develop a new generation of robotic-prosthetic hands that will incorporate key anatomical features of the human hand, especially, the passive dynamics defined by the joint stifftness and damping properties. This paper presents a design of a mechanism that can measure the passive moment of the human hand joint. We designed a motor-driven system, integrating a noninvasive and infrared motion capture system, that can control and record the angle, angular velocity and passive forces of the metacarpophalangeal (MCP) joint in the index finger. A total of 19 subjects participated in the experiments. We conducted two experiments to estimate the total passive moments of the MCP joint from the human subjects. The results showed that the novel design of the mechanism collected the precise passive moments and kinematic data, thus allowing us to develop a comprehensive understanding of the passive properties of the human hand joints.

scholarly journals Recent Advances in Myoelectric Control for Finger Prostheses for Multiple Finger Loss

2021 ◽  
Vol 11 (10) ◽  
pp. 4464
Author(s):  
Viritpon Srimaneepong ◽  
Artak Heboyan ◽  
Azeem Ul Yaqin Syed ◽  
Hai Anh Trinh ◽  
Pokpong Amornvit ◽  
...  
Keyword(s):  
Web Of Science ◽  
Myoelectric Control ◽  
Original Research ◽  
Prosthetic Hand ◽  
Precise Control ◽  
Prosthetic Hands ◽  
Prosthesis Retention ◽  
Finger Prosthesis ◽  
Artificial Hand

The loss of one or multiple fingers can lead to psychological problems as well as functional impairment. Various options exist for replacement and restoration after hand or finger loss. Prosthetic hand or finger prostheses improve esthetic outcomes and the quality of life for patients. Myoelectrically controlled hand prostheses have been used to attempt to produce different movements. The available articles (original research articles and review articles) on myoelectrically controlled finger/hand prostheses from January 1922 to February 2021 in English were reviewed using MEDLINE/PubMed, Web of Science, and ScienceDirect resources. The articles were searched using the keywords “finger/hand loss”, “finger prosthesis”, “myoelectric control”, and “prostheses” and relevant articles were selected. Myoelectric or electromyography (EMG) signals are read by myoelectrodes and the signals are amplified, from which the muscle’s naturally generated electricity can be measured. The control of the myoelectric (prosthetic) hands or fingers is important for artificial hand or finger movement; however, the precise control of prosthetic hands or fingers remains a problem. Rehabilitation after multiple finger loss is challenging. Implants in finger prostheses after multiple finger loss offer better finger prosthesis retention. This article presents an overview of myoelectric control regarding finger prosthesis for patients with finger implants following multiple finger loss.

Hand Prosthetic Design for Transradial Amputee by Using 3D Printing Technology to Enhance Life Quality

2021 ◽  
Vol 14 (2) ◽  
pp. 87-94
Author(s):  
Triwiyanto Triwiyanto ◽  
Torib Hamzah ◽  
Sari Luthfiyah ◽  
Bedjo Utomo
Keyword(s):  
3D Printing ◽  
Life Quality ◽  
Monitoring And Evaluation ◽  
Banana Peel ◽  
Physical Parameters ◽  
Prosthetic Hand ◽  
Printing Technology ◽  
3D Printing Technology ◽  
Glucose Levels ◽  
Prosthetic Hands

The target for this community service program is a resident of Jl. Parikesit RT 05 RW 03 Dusun Picis, Balongdowo Village, Candi District, Sidoarjo Regency. He had a work accident in one of the industries in the city of Sidoarjo in 2010 on the left wrist up to the fingers, so the doctor suggested amputation. He is actually still in his productive age (36 years old) but because of this situation, he is unable to carry out activities in the world of work and has decreased confidence in himself and avoids socializing in society. The purpose of this community partnership program (PKM) activity is to apply 3d printing technology in the manufacture of prosthetic hands for people who have transradial amputations as an effort to improve the quality of life. The implementation methods used are: a) the measurement of several physical parameters on the amputee such as the diameter of the arm circumference, the length of the amputated part, weight and height. In addition to physical parameters, we also carry out medical measurements, including obtaining information on health conditions such as blood pressure, heart health and blood glucose levels, b) designing prosthetic hands using 3D application programs and 3D printers, c) mechanical and functional testing for perform basic movements in the form of opening and closing the palms, d) monitoring and evaluation of the use of prosthetic hands. The results obtained from this activity are that the patient can use the prosthetic hand to assist with activities in carrying out daily activities. In this PKM activity, amputees have been tested, namely the movement of holding a mineral water bottle, holding a banana, peeling a banana peel and driving a two-wheeled motorized vehicle. Monitoring shows that patients need regular exercise in using prosthetic hands so that they are able to control and condition their use. In the future, several developments can be made, including in terms of control and size of the prosthetic hand so that patients can feel the benefits of a prosthetic hand that functions like a normal hand.

scholarly journals Objective Evaluation of Deep Uncertainty Predictions for COVID-19 Detection

2021 ◽  
Author(s):  
Hamzeh Asgharnezhad ◽  
Afshar Shamsi ◽  
Roohallah Alizadehsani ◽  
Abbas Khosravi ◽  
Saeid Nahavandi ◽  
...  
Keyword(s):  
Uncertainty Quantification ◽  
Performance Metrics ◽  
Confusion Matrix ◽  
Objective Evaluation ◽  
X Rays ◽  
The Novel ◽  
X Ray ◽  
Uncertainty Estimates ◽  
Chest X Ray ◽  
Novel Concept

Abstract Deep neural networks (DNNs) have been widely applied for detecting COVID-19 in medical images. Existing studies mainly apply transfer learning and other data representation strategies to generate accurate point estimates. The generalization power of these networks is always questionable due to being developed using small datasets and failing to report their predictive confidence. Quantifying uncertainties associated with DNN predictions is a prerequisite for their trusted deployment in medical settings. Here we apply and evaluate three uncertainty quantification techniques for COVID-19 detection using chest X-Ray (CXR) images. The novel concept of uncertainty confusion matrix is proposed and new performance metrics for the objective evaluation of uncertainty estimates are introduced. Through comprehensive experiments, it is shown that networks pertained on CXR images outperform networks pretrained on natural image datasets such as ImageNet. Qualitatively and quantitatively evaluations also reveal that the predictive uncertainty estimates are statistically higher for erroneous predictions than correct predictions. Accordingly, uncertainty quantification methods are capable of flagging risky predictions with high uncertainty estimates. We also observe that ensemble methods more reliably capture uncertainties during the inference. DNN-based solutions for COVID-19 detection have been mainly proposed without any principled mechanism for risk mitigation. Previous studies have mainly focused on on generating single-valued predictions using pretrained DNNs. In this paper, we comprehensively apply and comparatively evaluate three uncertainty quantification techniques for COVID-19 detection using chest X-Ray images. The novel concept of uncertainty confusion matrix is proposed and new performance metrics for the objective evaluation of uncertainty estimates are introduced for the first time. Using these new uncertainty performance metrics, we quantitatively demonstrate where and when we could trust DNN predictions for COVID-19 detection from chest X-rays. It is important to note the proposed novel uncertainty evaluation metrics are generic and could be applied for evaluation of probabilistic forecasts in all classification problems.

Sensory system integration of the designed mechatronics Touch Hand

Sensor Review ◽  
2016 ◽  
Vol 36 (2) ◽  
pp. 158-168 ◽  
Author(s):  
Drew van der Riet ◽  
Riaan Stopforth ◽  
Glen Bright ◽  
Olaf Diegel
Keyword(s):  
Haptic Feedback ◽  
Low Cost ◽  
Pressure Sensors ◽  
Sensory System ◽  
Prosthetic Hand ◽  
Prototype System ◽  
Lower Income ◽  
Content Type ◽  
Prosthetic Hands ◽  
Lower Income Countries

Purpose This paper aims to explore the electronic design of the Touch Hand: a low-cost electrically powered prosthetic hand. The hand is equipped with an array of sensors allowing for position control and haptic sensation. Pressure sensors are used on the fingertips to detect grip force. A temperature sensor placed in the fingertip is used to measure the contact temperature of objects. Investigations are made into the use of cantilever vibration sensors to detect surface texture and object slippage. The hand is capable of performing a lateral grip of 3.7 N, a power grip of 19.5 N and to passively hold a weight of up to 8 kg with a hook grip. The hand is also tested on an amputee and used to perform basic tasks. The amputee took 30 min to learn how to operate the hands basic gripping functions. Design/methodology/approach Problems of previous prosthetic hands were investigated, followed by ways to improve or have similar capabilities, yet keeping in mind to reduce the price. The hand was then designed, simulated, developed and then tested. The hand was then displayed to public and tested with an amputee. Findings The Touch Hand’s capabilities with the usage of the low-cost materials, components and sensory system was obtained in the tests that were conducted. The results are shown in this paper to identify the appropriateness of the sensors for a usage while the costs are reduced. Furthermore, models were developed from the results obtained to take into account factors such as the non-slip material. Research limitations/implications The research was restricted to a US$1,000 budget to allow the availability of a low-cost prosthetic hand. Practical implications The Touch Hand had to have the ability to supply the amputee with haptic feedback while allowing the basic grasping of objects. The commercial value is the availability of an affordable prosthetic hand that can be used by amputees in Africa and other Lower-Income countries, yet allowing a more advanced control system compared to the pure mechanical systems currently available. Social implications The Touch Hand has the ability to give amputees affected in war situations the ability to grasp objects in a more affordable manner compared to the current available options. Feedback from amputees about the current features of the Touch Hand was very positive and it proves to be a way to improve society in Lower-Income countries in the near future. A sponsorship program is being developed to assist amputees with the costs of the Touch Hand. Originality/value The contributions of this research is a low-cost prototype system than can be commercialized to allow amputees in the Lower-Income countries to have the ability of a prosthetic hand. A sensory system in the hand is also explained which other low-cost prosthetic hands do not have, which includes temperature, force and vibration. Models of the sensors used that are developed and calibrated to the design of the hand are also described.

Design, Build, and Test of a Permanently Implanted Prosthetic Hand

2002 ◽  
Author(s):  
Matthew Williams ◽  
Wayne Walter
Keyword(s):  
Range Of Motion ◽  
Grip Force ◽  
Point Of View ◽  
Neural Interface ◽  
Normal Operation ◽  
Human Model ◽  
Prosthetic Hand ◽  
Robotic Hand ◽  
Laminin 5 ◽  
Implant Length

The feasibility of a permanently implanted prosthetic hand was evaluated from both an internal biocompatibility and exterior mechanics point of view. A literature review of the issues involved in permanent implantation of a percutanious device was performed in the areas of bone interaction and fixation and neural interface control. A theoretical implant was designed for a 90th percentile male, using a HA-G-Ti composite material to provide a permanent base to which the hand could attach. Using a radial implant length of 1.87 inches and an ulna implant length of 1.32 inches, the simulated implant could withstand a push out force of 10.260 pounds. Using nerve guidance channels and microelectrode arrays, a Regenerative Neural Interface was postulated to control the implant. The use of Laminin-5 was suggested as a method of preventing the lack of wound closure observed in percutanious devices. The exterior portion of a permanent artificial hand was analyzed by the construction of a robotic hand optimized for weight, size, grip force and wrist torque, power consumption and range of motion. Using a novel dual drive system, each finger was equipped with both joint position servos as well as a tendon. Fine grip shape was formed using the servos, while the tendon was pulled taunt when grasping an object. Control of the prosthetic hand was performed using a distributed network of micro-controllers. Each finger’s behavior was governed by a master/slave system where input from a control glove was processed by a master controller with joint servo and tendon instructions passed to lower-level controllers for management of hand actuators. The final weight of the prototype was 3.85 pounds and was approximately 25% larger than the 90th percentile male hand it was based on. Grip force was between 1.25 and 2 pounds per finger, depending on amount of finger flexion with a wrist lifting torque of 1.2 pounds at the center of the palm. The device had an average current draw of 3 amps in both normal operation and tight grasping. Range of motion was similar to that of the human model. Overall feasibility of the device is examined and factors involved in industrial implementation are discussed.

scholarly journals Intraneural sensory feedback restores grip force control and motor coordination while using a prosthetic hand

2019 ◽  
Vol 16 (2) ◽  
pp. 026034 ◽  
Author(s):  
Francesco Clemente ◽  
Giacomo Valle ◽  
Marco Controzzi ◽  
Ivo Strauss ◽  
Francesco Iberite ◽  
...  
Keyword(s):  
Force Control ◽  
Sensory Feedback ◽  
Grip Force ◽  
Motor Coordination ◽  
Prosthetic Hand ◽  
Grip Force Control

scholarly journals Modeling and Analysis of a Visual Feedback System to Support Efficient Object Grasping of an EMG-Controlled Prosthetic Hand

2019 ◽  
Vol 5 (1) ◽  
pp. 207-210
Author(s):  
Tolgay Kara ◽  
Ahmad Soliman Masri
Keyword(s):  
Visual Feedback ◽  
Low Cost ◽  
Feedback System ◽  
Hand Gesture ◽  
Human Hand ◽  
Prosthetic Hand ◽  
Modeling And Analysis ◽  
Prosthetic Hands ◽  
Prosthetic Limbs ◽  
Computer Environment

AbstractMillions of people around the world have lost their upper limbs mainly due to accidents and wars. Recently in the Middle East, the demand for prosthetic limbs has increased dramatically due to ongoing wars in the region. Commercially available prosthetic limbs are expensive while the most economical method available for controlling prosthetic limbs is the Electromyography (EMG). Researchers on EMG-controlled prosthetic limbs are facing several challenges, which include efficiency problems in terms of functionality especially in prosthetic hands. A major issue that needs to be solved is the fact that currently available low-cost EMG-controlled prosthetic hands cannot enable the user to grasp various types of objects in various shapes, and cannot provide the efficient use of the object by deciding the necessary hand gesture. In this paper, a computer vision-based mechanism is proposed with the purpose of detecting and recognizing objects and applying optimal hand gesture through visual feedback. The objects are classified into groups and the optimal hand gesture to grasp and use the targeted object that is most efficient for the user is implemented. A simulation model of the human hand kinematics is developed for simulation tests to reveal the efficacy of the proposed method. 80 different types of objects are detected, recognized, and classified for simulation tests, which can be realized by using two electrodes supplying the input to perform the action. Simulation results reveal the performance of proposed EMG-controlled prosthetic hand in maintaining optimal hand gestures in computer environment. Results are promising to help disabled people handle and use objects more efficiently without higher costs.

A custom, functional and lifelike passive prosthetic hand for infants and small toddlers: Clinical note

2020 ◽  
Vol 44 (3) ◽  
pp. 180-184
Author(s):  
Arezoo Eshraghi ◽  
Jaeeun Yoo ◽  
James Klein ◽  
Ian Mckenzie ◽  
Gabrielle Sebaldt ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Upper Limb ◽  
Low Cost ◽  
Prosthetic Hand ◽  
Functional Requirements ◽  
Infants And Toddlers ◽  
Clinical Note ◽  
Alloy Wire ◽  
Prosthetic Hands ◽  
Limb Deficiencies

Background and Aim: For infants and small toddlers with congenital upper limb deficiencies, terminal devices mainly provide either cosmesis or functionality. We report a clinical note about fitting a child with a low-cost passive hand targeting both functionality and cosmesis. Technique: An elastomeric, alloy-wire-reinforced hand was fabricated using additive manufacturing to allow independent positioning of the digits. A clinical pilot in-home evaluation was conducted on a child with upper limb loss. Discussion: The fabricated hand met the functional requirements but required a cover for cosmesis due to a poor surface finish associated with the fabrication technique. The participant child was comfortable using the prosthesis for various tasks. The parents were satisfied with the hand’s function and cosmesis when covered with a cosmetic glove. This work demonstrated a new design and process that may in the future improve the utilization of prosthetic hands to promote early prosthesis use and a child’s development. Clinical relevance Early prosthesis use is important for infants and toddlers. Additive manufacturing may enable the fabrication of custom passive prosthetic hands that provide both cosmesis and functionality.

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