Browsing by Subject "hand prosthesis"

Now showing 1 - 11 of 11
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    ANALYSIS OF FINGER POSITION DURING TWO AND THREE-FINGERED GRASP: POSSIBLE IMPLICATIONS FOR TERMINAL DEVICE DESIGN
    (2008) Maitland, Murray E.; Epstein, Molly
    Analysis of human hand kinesiology has been used to justify the design characteristics of terminal devices. The human hand is a complex mechanical structure consisting of 15 articulations controlled by over 30 muscles for the 5 fingers. It functions as a communication, sensory, grasp and manipulation structure. Separating essential hand kinesiology that is linked with each hand function might allow for the efficient development of terminal devices where there is one primary function such as grasping. It follows that to develop an effective grasping mechanism for a terminal device there should be a clear understanding of hand motions as they relate directly to the grasping function. The conceptual framework used to characterize grasping functions will most likely influence the development of terminal devices. There is a growing body of literature that is refining the way we think of grasping activities, and may impact the design of terminal devices. For example, researchers have described the simplified coordination of hand motions during grasp as “synergies” or “virtual fingers”, where there are predictable dependencies of one finger on another. Using conceptual approaches such as the “virtual fingers” concept will reduce the complexity of the description of the hand/object/task interaction
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    Cable Driven Multi-Articulating Fingers, Providing Compliant Grasp For The Partial Hand Amputee.
    (2008) Mikosz, Matthew J.
    This article will describe a new concept in fitting the partial hand amputee to offer them enhanced grasp and improve their overall functional ability with the prosthesis. The concept is to activate the mechanical fingers through existing wrist motion to provide active grasp that is compliant to any object.
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    Compliant Hands: The Next Evolution of the Prosthetic Hand
    (2008) Miguelez, John M.
    While the last 10 years have brought significant advancements to the upper extremity prosthetic patient population, the function of prosthetic terminal devices has been limited by their inability to mimic the myriad grasping patterns of the human hand. Recently, several groups have made considerable progress in the development of terminal devices that offer more anatomical articulation while retaining the aesthetics of a human hand.
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    DESIGN AND PRELIMINARY EXPERIENCE WITH FLUIDHAND MK III
    (2008) Schulz, Stefan; Pylatiuk, Christian; Kargov, Artem; Werner, Tino; Gaiser, Immanuel; Reischl, Markus; Oberle, Reinhold
    The third generation of the fluidic hand currently is in the process of clinical trial. The new hand combines functionality and cosmesis. It has the natural shape of a human hand and multiple new functions. The grasping operation is built in an adaptive way according to the biological example. This means that objects are enclosed with positive locking. The big contact area and soft passive elements considerably reduce the grasping force required to hold an object securely. Starting from a natural basic hand position, all actuators can be controlled individually by two myoelectrodes in the socket. The software allows for a quick selection of the most important grasping patterns. Besides the multifunctional control, features of the new hand like the force feedback system which gives the patient a sense of feeling and operation of a (computer) keyboard with the index will be depicted.
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    ELECTRONIC PROSTHESIS FOR THE PARTIAL HAND AMPUTEE
    (2002) Miguelez, John M.
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    Experience with Electric Prostheses for the Partial Hand Presentation
    (2008) Lake, Chris
    Limb deficiency distal to the wrist represents a common presentation, yet a difficult level to treat with a functional prosthesis. (1) Historically, prosthetic treatment has been limited due to the lack of acceptable electric prosthetic options. Poor results were attributed to challenges including functional limitations of prosthetic technology, patient discomfort, cosmetics and absence of tactile sensation. (2) Until the late 1990s, the lack of acceptable electric prosthetic options as well as concise treatment parameters limited prosthetic treatment. John Michael, M Ed, CPO, FAAOP in the early 90s precisely described the challenge when stating, “The dilemma facing physicians and prosthetists is to determine when our admittedly limited prosthetic armamentarium will add a measure of function to diminish the substantial loss faced by the partial-hand amputee.” (3) As the specialty of upper limb prosthetics realizes the attention of many different research endeavors, advances in upper limb technology once only found in the research laboratory or in the minds of idealists are beginning to evolve toward commercial availability. These current and future additions to the prosthetic field create a challenge. With the renewed focus on the partial hand level, variables such as residual limb presentation, surgical results, and anatomical stability point to the need for concise treatment parameters.
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    Grip Force Feedback in an Electric Hand - Preliminary Results
    (2008) Sears, H.; Iversen, E.; Archer, S.; Linder, J.; Hays, K.
    Feedback of sensation has long been the dream of developers (and wearers) of prosthetic hands, and many earlier efforts have made progress, but never a practical commercially-available system. Although grip force feedback (GFF) is an obvious shortcoming in a hand prosthesis, it has been slow to develop because of the innate difficulties of providing consistent and accurate feedback information to the wearer of an electric hand. A truly useful GFF system must provide, 1) true clinical relevance (we feel it should demonstrably improve control of grip force, contribute to a more natural feel, and represent an acceptable ratio of cost to benefits provided), and 2) technically provide a practical system which can operate for months reliably, and be small enough to install into a cosmetic-looking prosthesis.
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    Michelangelo 03 - A versatile hand prosthesis, featuring superb controllability and sophisticated bio mimicry
    (2008) Puchhammer, Gregor
    Rapid progress has been made recently in all components of upper limb myoelectric prosthetics, and revolutionary new concepts in controlling these devices are part of ongoing R&D activities. Nevertheless there is a need for new prosthetic hands capable of providing a whole new set of functions.
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    Multi-articulating Hands & Fingers – Technical Strategies for Improved Patient Function and Myoelectric Uptake
    (2008) Newman, Phil
    Since the commercial release of the i-LIMB Hand in September 2007, and the subsequent R&D release of ProDigits for partial hand users, there has been much interest from clinical professionals – to date (18 March 2008), more than 160 patients worldwide have been fitted with the i-LIMB Hand.
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    Neurofuzzy Logic as a Control Algorithm for an Externally Powered Multifunctional Hand Prosthesis
    (2002) Ajiboye, Abidemi Bolu; Weir, Richard F.; Heckathorne, Craig W.; Childress, Dudley S.
    We propose an algorithm based upon neurofuzzy technology. We believe that because of the inherent “fuzziness” of human activity, a control algorithm based on fuzzy logic may have advantages for multifunctional prosthesis control. We seek an acceptable compromise between the number of electrode sites used and processing complexity, and thereby desire not more than three to four control sites to control three to four DOF. This approach delivers more information to the system and, by using fuzzy logic, reduces the complexity of the processing.
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    THE WILMER PASSIVE HAND PROSTHESIS FOR TODDLERS
    (2008) Plettenburg, Dick H.
    The WILMER Passive Hand Prosthesis is developed for children aged one through five years. This harnessless hand prosthesis aims primarily at giving the child two arms of equal length. The hand features an easy to control passive prehension function. The movements of the fingers are mechanically coupled to the movements of the thumb. By pressing an object against the fingertips, the hand opens. By slightly tilting the object, it can be grasped. The hand prosthesis can be mounted in a passive friction wrist rotation prosthesis, available in different outer diameters. The hand features a low mass construction, which proved to be very robust and reliable in clinical tests. For the age group mentioned the WILMER Passive Hand Prosthesis is one of the very few available with a prehensile function. It stands out in functionality and in cosmetics as compared to other passive hand prostheses on the market.