[ODE] All Terrain Robot

[Abheek Bose]

Hi,

My name is Abheek and I am trying to simulate an all terrain robot. The
problem is that the robot is unable to turn on the spot (probably due to
massive friction on the wheels) However, we have a few real robots (similar
in shape) which can turn on the spot. Has anyone had any experience with
this?
The robot has 6 powered wheels and one castor wheel
(passive) at the back... the powered wheels are on vertical bars(legs u
can say)which are capable of moving up and down only.. i will try to put a
picture somewhere soon!
Is there any major difference in having an AMotor Joint
instead of a hinge on the wheels?  I tried attaching an AMotor Joint but it
does not clamp the wheels to the axis for some reason (do i need to use a
hinge AND an AMotorJoint?). Using only the hinge on the other hand works
fine.... but is it "real" ?
One final question... when i set a velocity to a hinge joint and a max
torque,is the torque on the wheel ALWAYS the max torque? if not is
there anyway to
determine what torque is acting on the joint?

thanx!

abheek