[ODE] implementing sensors in ODE

[Stefan Castille]

Firstly i'd liek to thank those who have helped me in my previous problem.
It was indeed a too large stepsize that caused the crash. I thought 0.001
would be small enough but it wasn't :)

Anyway I'm now a bit further and need to implement 2 different sensors.
The first is a motion detector and i think i figured out how to do that.
I connect it to a body and measure the speed and angular rotation of the
body and use that to get a measure of motion for the sensor. I don't know
if there is a better way to do it but this seems to work fine for now.

The problem i have now is a pressure sensor. My robot has 8 pressure
sensors at the feet, 4 on each foot. I tried adding 4 small objects on
each foot and use dBodyGetForce(dBodyID) on each of the object to get some
measure of pressure but all i get are 0 0 0 vectors. Am i wrong in trying
to get a force this way and if so, can anyone give me an idea on how to
implement a pressure sensor?

A last question is this, what is the default measuring system for ode? Is
it meter/kg/secs or anything else? So if i put gravity on 9.81 will i have
earths gravity or should i use a different scale?

Stefan Castille