Liquid-fueled actuation for an anthropomorphic upper extremity prosthesis.
This paper describes the design of a 21 degree-of-freedom, nine degree-of-actuation, gas-actuated arm prosthesis for transhumeral amputees. The arm incorporates a direct-drive elbow and three degree-of-freedom wrist, in addition to a 17 degree-of-freedom underactuated hand effected by five actuators. The anthropomorphic device includes full position and force sensing capability for each actuated degree of freedom and integrates a monopropellant-powered gas generator to provide on-board power for untethered operation. Design considerations addressed in this paper include the sizing of pneumatic actuators based on the requisite output energy at each joint; the development of small low-power servovalves for use with hot/cold gases; the design of compact joints with integrated position sensing; and the packaging of the actuators, on-board power, and skeletal structure within the volumetric envelope of a normal human forearm and elbow. The resulting arm prototype approaches the dexterous manipulation capabilities of its anatomical counterpart while delivering approximately 50% of the force and power output of an average human arm.
Fite
Kevin B
KB
Vanderbilt University, Nashville, TN 37265, USA. kevin.fite@vanderbilt.edu
Withrow
Thomas J
TJ
Wait
Keith W
KW
Goldfarb
Michael
M
D000886:Anthropometry; D001132:Arm; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D004551:Elbow Joint / Q000033:anatomy & histology / Q000473:pathology; D004581:Electronics; D004867:Equipment Design; D006225:Hand; D006801:Humans; D007596:Joints; D008953:Models, Anatomic; D018482:Muscle, Skeletal / Q000473:pathology; D011474:Prosthesis Design; D034941:Upper Extremity / Q000473:pathology*; D014953:Wrist / Q000033:anatomy & histology / Q000473:pathology