Desmopan aliphatic thermoplastic polyurethane (TPU) was selected by TRS for use on the gripping surface of its high-performance Grip 3 prosthetic prehensor
Childress and his laboratory developed many important rehabilitation technologies, including the first self-contained electromyography-controlled prosthetic arm, the sip-and-puff wheelchair controller, and the synergetic prehensor
. Childress also published more than 130 publications that helped to broaden the knowledge base in the areas of prosthetics, orthotics, assistive technology, and human walking.
Several groups have tried to design a body-powered prehensor that provides both VO and VC modes.
Finally, we perform a pilot study in which persons (five with intact arm and two with amputation) performed the SHAP with this TD using four prehensor configurations: VO or VC (assigned in random order), the alternative mode, the mode they preferred for the task (VO or VC), and the non-preferred mode.
One of the main causes of abandonment is the limited function of the prehensor , especially when compared with an intact contralateral hand.
A choice must accordingly be made on how the active force generated by the user and transferred via the cable should be used, i.e., whether the cable force should open or close the prehensor. In a voluntary closing (VC) device, the user actively closes the device and some passive element, such as a spring, returns the prehensor to the default open state.
When we would add a cosmetic covering to such a device, this would considerably increase the total required work of the prehensor
. Devices that have a more complex mechanism, with more joints and transmissions, require much more work than relatively simple mechanisms.
Pioneering work by Dudley Childress on synergetic prehension  led to the development of multiple upper-limb prosthetic devices, including the Hosmer Synergetic Prehensor
and the Otto Bock Electrohand for Children.
Comparison of three myoelectrically controlled prehensors
and the voluntary-opening split hook.
TRS Inc., a Pittsburgh company dedicated to the design of body-powered prosthetic devices, has announced "new generation of prosthetic prehensors
(hands)." Said to offer a "more realistic, user-friendly" prosthetic option, the Grip 3 features a soft-grip texture that is provided by Desmopan aliphatic thermoplastic urethane (TPU) from Bayer Polymers, which is used to mold the device's gripping surface.
measured several VO and VC child-size prehensors
These technologies range from the highly advanced, such as myoelectric-controlled prosthetic arms or stair-climbing wheelchairs (http://www.independencenow.com/ ibot/index.html), to the simple, such as manual wheelchairs or mechanical hook prehensors
. Many factors affect user acceptance of such devices, including cost, simplicity, aesthetics, maintenance, and ease of control.