The proposed research will develop and pilot test new types of controls to simplify the operation of modern prosthetic wrist/terminal device systems that have multiple movement capabilities. Our approach will integrate common, inexpensive sensors such as accelerometers and gyroscopes into prosthetic components that will be utilized to implement "smart" control schemes selectable by the user. Smart controls will include autoleveling to keep a held object level during movement of the arm, selectable stiffness that allows the user to change the wrist stiffness from rigid to flexible, and smart coupling that will coordinate wrist movements with upper arm movements to simplify activities. The smart control modes will be informed, in part, by a motion study to understand the normal coupling action of the hand-wrist during everyday tasks and activities that we will perform. Our work will include several stages of human subjects testing to refine the design and to compare its utility to conventional myoelectric controls. At the end of the 3-year project period, we expect to have a strong prototype of the smart control systems ready for commercialization.

For military populations, this research will lead to an improved strategy to restore upper limb function for Wounded Warriors. As of July 1, 2011, 270 Wounded Warriors from conflicts in Iraq and Afghanistan had been treated in all U.S. Military facilities that had major upper extremity amputation. Our research has application to these and all other military, Veteran, and civilian upper limb amputees who will utilize a multi-degree of freedom wrist. Our smart control system will be usable with any terminal device and wrist provided that sufficient degrees of freedom and control sites are available. It will be usable by transradial amputees with our pattern recognition controls, but will also be usable by amputees with higher levels of limb loss who have undergone targeted muscle reinnervation surgery.

Although the state of the art in commercial upper-extremity prosthetics had been stagnant for decades, recently a commercially available EMG (electromyography) pattern recognition system has become available (COAPT, IL, USA). COAPT is implemented on embedded systems; however, the entire system is closed to researchers and clinicians, making the modification of the controller impossible. Therefore, we will develop an open and configurable embedded system to implement both voluntary controls and smart control modes. Our commitment to open source and the early usability testing by subjects with amputation means that the control systems that we develop will be compatible with other devices on the market and will be informed by user needs and preferences. The resulting controls system will be enable more function with less effort than other available products, thus dramatically improving the lives of amputee users.