4. Leverhulme Hand

The devices have separate motions of fingers and thumb. They are able to achieve both precision and power grips. The fingers curl continuously from fully extended to fully flexed. They fit within advanced silicone external gloves which give them a very natural static appearance. The dynamic appearance is enhanced by the finger design and motion control. The electronics are designed to run for up to 12 hours on a single charge of the Lithium-Ion batteries. The hands are adult small to medium in size so they can be used by a wide range of users. The design specification was derived from a survey of users in the Oxford region [7], the details of the specification and design concepts are detailed in [8].

An advanced system as embodied in the Leverhulme hand allows for the hand to be flexible to the needs of the user and well as to provide additional information concerning the status of the hand. In addition to the technical details provided in [8], the microprocessor has a serial link that conforms to the RS232 standards. This link can therefore provide information to an external computer about the inputs to the hand and its state. The link then inputs to a PC-based computer and a program can display the data on the screen. This information can be used for calibration and training. Two forms of display are used.

Figure 1 An example of the Leverhulme Hand mounted upon a socket for wearing by a person with a below elbow absence. The complete system would be covered with a cosmetic external glove .