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Lessening resistance on wheelchair brakes
#1
Hi - I am working on a wheelchair rather than a bicycle however it does have caliper brakes on both back wheels which are controlled by regular brake levers located on the wheelchair hand grasps (at the back). I want to control the brake levers remotely via two servo motors. I need to move the location of the brake levers so that someone can still push the wheel chair and that the servo motors won't be in the way of the users hands.

I need the resistance on the brake lever to be as 'light' as possible so that the servo motors can have the torque to open/close the brake lever incrementally. I know that friction can be caused by dirty cables and rusting calipers but the brake calipers and cables seem clean and rust free. Since I moved one of the brake levers down to the lower part of the wheelchair (see image attached) the lever resistance seems greater. There is no kink in the cable but I was wondering is there a link between brake friction and excess cable and/or the brake cable not being fixed at all times to the tubular steel ? I also read that the shorter the cable the more efficient the pulling mechanism is....would it be worth cutting the cables as short as possible and placing the motors as close as possible to the caliper or would this make any difference ?

Any advice would be great.

http://imageshack.com/a/img923/6131/9EYAXb.jpg
http://imageshack.com/a/img924/3600/EI7VBw.jpg
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#2
Attach the servo motors directly to the brakes, getting rid of the cables altogether for the motors.  Leave the cables and levers in place only for emergency manual actuation.
Nigel
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