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CHAPTER 34
FIG. 247.
with a complete lesion below
€5,
while the other patient, a tetraplegic below €4 with
paralysis of all muscles of both upper limbs, controls the device by breath. Recently,
Mr A.Dudley, an engineer, working in co-operation with my successor Dr JJ.Walsh,
has continued research on the Zimmer's Power Drive chair and the A.C. Cars Ltd
'Epic' chair, Mark 2 (Model 102). He designed an electric simulator consisting of a compact
box with a multi-pin socket fitted at each end into which the operating control is plugged.
The simulator contains its own power source in the form of a P.P.4 battery. Controls for
arm, chin, head and breath are available according to the tetraplegic's individual handi
cap. Dudley's device has recently been accepted by the Ministry, as its price is low, for
electrically powered wheelchairs issued by the National Health Service. However, it
has not yet proportional speed control, but research to achieve this is in progress.
HAND AND POWER CONTROLLED TRICYCLES
Hand-propelled tricycles for severely disabled people have been in use for hundreds of
years. As an example Fig. 248 demonstrates a tricycle for propulsion by hand-operated
pedals which a German paralysed watch-maker from Niirnburg constructed himself
in 1652, and Fig. 249 shows a tricycle with worm-drive control of Connt of Gruyere
