Re: New technique: three position piston control

In lugnet.technic, Mark Bellis wrote:

<snip>
>
> Interesting stuff!  Should make walkers move more smoothly, with the possibility
> of more groups of legs.  The trick will then be reversing all the groups, since
> it was easier with just two, using two polarity reversers.
>
> I have a centre-stop mechanism for pneumatic steering for a JCB.  It's not part
> of an automatic system though, since I don't yet have an application for that.

Was this single or dual piston?

>
> Does your centre stop cylinder stop accurately in the same place every time,
> even under different pressure conditions?  I thought if you put a lot of source
> pressure into the cylinder it might overshoot the mid-point, whereas with low
> pressure it would creep up to it.  Accurate repeatable positioning is one of the
> challenges of this scheme.
>
> Mark

Kevin