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Cycler Presentation Robot - designed and constructed by David Buckley
Height 48inch, (121cm)
Weight 32.5Kg (71.65lb) including batteries and covers
Speed in Slow-mode ~25cm/sec, in Fast-mode ~50cm/sec
Starts in Slow-mode and automatically switches to Fast-mode after ~5seconds

Stability and Load tests.

Stability tests.

Shelley maximum stable tip angles - Back 15deg. Forward 15deg. Side 20deg.
(The ADA recommended slope for commercial and public access wheelchair ramps is 5 degree incline, see list below)

Forces necessary to tip Shelley

All measured horizontally at Shelley's neck level, 39inch (1m) with Shelley on a flat floor.
Measured with all covers on unlike the photographs.
All measured with a spring-balance which only goes up to 14lb.
Forward - well over 14lb, maybe 20 - 25lb
Sideways -a lot more than 14lb, maybe 30+ lb
Backwards - 7lb going up to 11lb as soon as the rear 'trolley wheels' hit the ground.
Diagonally - a lot more.

Load tests.

Shelley carrying 5.5Kg at maximum forward extension for stability.
Note - This is approximately equivalent to 14Kg at beyond arms reach for a normal sized human. (Or 28Kg at arms reach!)

Shelley carrying 56lb (~25.5Kg) at maximum forward and backward extensions for stability.
Note Shelley weighs 32.5Kg with batteries and covers and so is carrying over 3/4 of its weight.

Front ~9.25inch, Back ~5.75inch from body centre line

Wheelchair ramps
A guide to the sort of slopes likely to be encountered in domestic and office environments.

1:12 Slope (Or 8.3%, 5 degree incline)

1:8 Slope (Or 12.5%, 7 degree incline)

2:12 Slope (Or 16.7%, 9.5 degree incline)

3:12 Slope (Or 25%, 14.5 degree incline)

Data from