Sinclair Harding Navigation Clock :

The Spine robot was an original concept by Volvo apprentices in the early 80’s.They were asked to complete a production project by management and derived the idea when one of apprentices noticed how a blade of grass bent when in a breeze.

The robots were only used for paint spraying as axis accuracy was only +/- 1 mm which owing to nature of the design was a remarkable feat in its own right! (industrial robots used for welding and manipulating usually have a repeat accuracy of 0.02mm or 2 microns).

When the Spine company was eventually established 25 of these robots were only ever made .Volvo had 15 , Volkswagon had 5 and JCB had 2.JCB then bought a further 3 in component form when Spine went into receivership being a victim of its own success .The company tried to fulfil to many orders at the same time ,involving a massive outlay of capital ,only to see some orders cancelled due to the 80’s recession and were left with massive tooling costs and development debts.

I  had the pleasure of building one of these robots that was in component form at JCB and always thought it would be a superb machine to try and replicate in Meccano .The originals were about 12 feet high at full stretch and my model dwarfs in 18 inches only.

The original robot had seven axis of movement, two in the lower arm, two in the upper arm, and three axis of movement in the wrist (roll, pitch and yaw).

Due to size and weight I have decided to model just the four arm axis. X and Y are the two upper arm axis (the closest to the base) and Z and B axis are the lower arm (think of a human arm).

The original was powered by hydraulics and servo valves for movement , with positional feedback being potentiometers driven by pulleys and wire .Also strain gauges were used to calculate offset movement due to load due to gravity or collision.

This being only an experimental model is driven by a simple 4 axis controller…..I may build a bigger unit and hook it up to a computer later!