Ok. For Paul, here is a vague attempt at showing the internal workings of the Big Blue laddie. If I get the chance, and the covering comes off, I will take some more informative pics. Here's some clues though, for starters.
View of arm control mech.Notice the upper arm is held on a swivel which can be pulled to make the arm raise sideways. The whole assembly is on a 1 3/4" aluminium tube through some pillow block bearings. Through the tube runs a 1" steel bar running on oilite brgs, which is the control for the forearm.
Another view of same
Look very carefully. This is looking from behind the head (which isn't there), forwards and down. You can see the swivel that houses the "neck" - 1" bar in oilite again. Below that you can clearly see the tubes carrying the arms, the levers on the inside of the 1" bar, and the ally levers welded to the tubes. There are no ropes on at this point. If there were, you'd see them passing down to the wheels.
Here you can see big wheels and small, and ropes attached. Look in the centre at two ropes heading up at 11 o'clock. They are RHS arm, upper and lower control. LHS ropes are hidden. The lower ropes are heading to the legs. Notice also a load of ropes attached to a tube welded to the frame, below the wheels. These are actually bungees (shock cord), used to stop over-run of the wheels, or to create tension to ensure the ropes pulled by the puppeteers (which are led to the big wheels), stay taught on the wheels, as if those ropes go slack, they can come off! This took lots of experiment to get right.
There are also ropes attached to that tube which go down into the legs and act as ligaments to control toe movement when he walks.
This is how we get him up and down off his "bed", ready to be hooked onto the handler. Lots of pulleys (down behind his feet), four puppeteers to haul up on rope. A Petzl Grigri to let him down though, nice and gentle. His legs are sitting on custom PU foam supports. Lots of fun pouring rapidly expanding, and very hot foam, into gaffa taped up tyvek bags. (there was a roll lying about saying "use me")
The carrier plate, also showing control ropes.
Carrier plate swivel. This is currently fixed in position as I never found the time to fit an actuator.