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This paper presents the design of an anthropomorphic 21 degree-of-freedom, 9 degree-of-actuation arm prosthesis for use by transhumeral amputees. The design leverages the power density of pneumatic actuation with the energy density of liquid propellants to obtain a self-powered dexterous prosthesis in which all of the requisite power, actuation, and sensing is packaged within the volumetric envelope of a normal human arm. Specifically, the arm utilizes a monopropellant as a gas generator to power nine pneumatictype actuators that drive an elbow, three wrist degrees-offreedom, and a 17 degree-of-freedom compliant hand. The design considerations discussed in this work include the design of compact, low-power servovalves; the choice of actuators based on energetic requirements of a normal arm; the design of compact elbow and wrist joints with integrated position and force sensing; and the components of the compliant hand design. The liquid-fueled prosthesis is expected to approach the dexterity of an anatomical arm and is projected to deliver half of the force and power output of an average human arm.

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Abstract²A simplified dynamic model of a household refrigerator incorporating a single evaporator, variable position air damper, and variable speed evaporator fan is constructed. It is shown that, with proper parametric values, the model can accurately recreate data measured from such a refrigerator. Using the model, a model reference adaptive controller is derived and executed on a physical plant. The new controller improves upon the temperature tracking accuracy of stock controllers and is shown to adapt to changing unit types, environmental conditions, and loading cases.