1,721,023 research outputs found
Controlling a prosthetic arm with a throat microphone
No full textThe aim of the present paper is to illustrate the phases of design and application of an innovative input source for an EMG upper limb prosthetic arm: a laryngophone, otherwise called throat microphone (t - mic). In the last years several different input sources were explored, from the implantable myoelectric sensors to the mechanomyographic sensors. The idea of controlling a prosthesis with vocal commands is quite recent but seems to be promising in helping users to better control their devices, improving the quality of their life
Applicazioni Di Riconoscimento Vocale per Protesi Mioelettriche di Arto Superiore
No full textUna protesi mioelettrica è comandata dal paziente tramite contrazioni muscolari rilevate dai sensori elettromiografici. Eseguire movimenti complessi con tale ausilio, specie per pazienti con amputazioni prossime al livello della spalla, comporta dunque l’esecuzione di una notevole sequenza di movimenti. Considerando poi che spesso una protesi è gestita con un comando circolare dei motori (l’utente comanda, a rotazione e con opportuna selezione, prima il motore della mano, poi quello del polso, poi quello del gomito e di nuovo quello della mano) è comprensibile come un’azione apparentemente semplice quale quella di portare un bicchiere alla bocca possa risultare difficoltosa per chi non può utilizzare entrambi gli arti sani.
A questo proposito si è pensato di dotare la protesi mioelettrica del centro protesi INAIL di Vigorso (Bo) di alcune funzionalità a comando vocale.
In questo modo all’utente basterà pronunciare determinate parole chiave e la protesi svolgerà autonomamente movimenti complessi che comportano la sequenza di più azioni
Analisi delle strategie di controllo per protesi di arto superiore in pazienti con amputazioni transomerali o disarticolati di spalla
No full textQuesto articolo presenta uno studio condotto su un campione di dieci pazienti del Centro Protesi INAIL (Istituto Nazionale Assicurazione Invalidi sul Lavoro) di Vigorso di Budrio (Bo), per valutare l’efficienza e le potenzialità della protesi di arto superiore, attualmente in uso presso tale centro, in soggetti con amputazioni transomerali o disarticolati di spalla. Lo studio presenterà l’analisi dei segnali elettromiografici utilizzati per il controllo della protesi e misurati direttamente sui pazienti in esame, e le strategie di controllo implementate nel sistema. Verranno quindi messi in evidenza punti di forza e punti deboli della attuale generazione di protesi, proponendo poi possibili soluzioni agli eventuali problemi riscontrati
How to transform an upper limb prosthetic arm in a wheelchair arm
No full textA myoelectric upper limp prosthetic arm is an aid with several degrees of freedom, designed to allow a patient to perform several movements (typically opening-closing the hand, rotating the wrist clockwise and counter clockwise, flexing-extending the elbow). The new version of the INAIL (Istituto Nazionale Assicurazioni Infortuni sul Lavoro, i.e. Italian National Assurance Institute for work accidents) prosthetic arm includes also a shoulder unit, able to perform two movements (abduction/rotation). Seeing this aid from another point of view, overturning the idea of prosthetic arm, it can be obtained a robotic arm that can be installed on a wheelchair, using the same motors, the same structure, the same electronic and mechanical components. This device is already able to perform task such as reaching /manipulating objects, and can be used to assist the tasks of eating and interacting with the environment. Of course the device must be a little bit adapted (a grip with a real hand shape is not appropriate!) , and its purposes, when mounted on a wheelchair, are different from the ones related to an amputee patient. Anyway, even if it cannot have the same performance of a Manus® arm, the INAIL prosthetic arm is cheaper and overall is already funded by the Italian National Health Service, which is a very good start point for this project. The aim of the paper is then to investigate the possibility of this transformation and to illustrate the capability of the first prototype in term of range of movement, usability and versatility
A CAN-based distributed Control System for Upper Limb Myoelectric Prosthesis
No full textThe paper presents the definition of a Prosthetic Protocol, specifing an application profile based on CAN Bus standard. Aim of this definition is to realize an upper limb prosthesis control oriented bus, which grant an efficient sensors and actuators management, with the possibility both of centralized and distributed control, through the transmission and reception of high level commands and data. The enlarge possibility and reconfigurability of the system will be necessary aspects on following discussion
DESIGN OF A NEW EMG SENSOR FOR UPPER LIMB PROSTHETIC CONTROL AND REAL TIME FREQUENCY ANALYSIS
No full textMyoelectric prosthesis are aids that try to give back to patients a bit of autonomy and
indipendence in their life. Several control techniques were explored in the past, but still the
electromyographic (EMG) control remains the most widely used method. Most of the
commercial EMG electrodes for prosthetic control available on the market modify the
acquired signal acting a heavy frequency filtering, making the signal more clear and better
suitable for prosthetic control even if the information related to its frequency behaviour are
lost. This information instead would be precious for a frequency analysis, to face and solve
the problem of musclular fatigue, an effect that arises in case both of repetitive movements
and sustained isometric contraction, as literature reports, causing an amplitude increasing and
a spectrum shift toward lower frequencies of the EMG signal. This, in turn, can cause
problems in the control of myoelectric prostheses [1]. The aim of this work is hence to
illustrate the design of a new EMG electrode suitable both for prosthetic control and
frequency analisys, taking into account the problem of muscular fatigue
How accurate is the estimation of elbow kinematics using ISB recommended joint coordinate systems ?
No full textExperimental Evaluation of the Mechanical Efficiency of One-Degree of Freedom Mechanisms by a Low-cost Test Bench
No full textA method to experimentally estimate the mechanical efficiency of one degree of freedom mechanisms actuated with DC motors has been developed and is outlined here. Global efficiency of an electromechanical system is introduced as the ratio between the output mechanical energy provided by the mechanism and the electrical energy supplied to the motor during given load cycles. Global electrical and global mechanical efficiency are the factors of the global efficiency relative to the motor performance and the kinematic chain performance respectively. The method requires the use of a cheap test bench which must measure the signals of voltage and current supplied to the DC motor as well as the instantaneous position of the motor shaft. The method has been applied to estimate the global mechanical efficiency of two prosthetic mechanisms and some preliminary results are reported here
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