Putting the Brakes Back On

I had convinced myself along the way that because the wheel gearboxes used a worm drive, they couldn't be driven by the wheels.

Turns out that's a load of crap. If the machine is on a slope and in motion and the controllers drop out (so there's no motor braking) the machine will keep on rolling. That explains this thing on the other end of the input shaft of the wheel gearbox:

Which takes what I guess would be called a brake disk:

Then a friction disk thing goes on top:

And then a pressure plate:

A later pic with the gearbox back on the machine - there's a spring each side to apply pressure:

And the cover plate goes on over the whole lot:

This mild braking action improves manoeuvring as it stops an un-driven wheel from freewheeling, however at high speed it tends to get rather hot, and I'm not convinced it will apply complete braking action on a steep incline - it's certainly something to be improved down the track.