In the paper I give some detailed geometric analysis of Mecanum wheels and work out natural parametrizations of
the roll surface (Eq. (4)) and its meridian curve (Eq. (5)). The result can be used for manufacturing the rolls precisely.
Alternatively I investigate suitable approximations of the roll surface by torus patches (Section 3).
Moreover I show that the instantaneous contact point C of a roll moves from one side of the Mecanum wheel to the
opposite as the wheel rotates. This is neglected in the standard literature which might be a reason for deviations between
the real and the predicted motion of a vehicle on such wheels. I develop the differential equation ruling the connection
between the vehicle velocity and the angular velocity of the wheel (Eq. (15)). This could be the starting point for some
more accurate analysis of the kinematics of Mecanum wheel vehicles in future research work. As a drawback the formula
requires the knowledge of the rotation angle function u = u(t) of the wheel which may not be available in practice.
Finally, by returning to the simplified equation between the vehicle and wheel velocities, I deliver some nice geometric
characterization of singular wheel constellations (Theorem 2)
Some investigations were made into the system and it quickly became apparent
that movement about the free axis was completely undesirable as it would allow the
sides of the hub to foul the ground. Movement of this form would also affect the
motion of the Mecanum wheel, as the sideways force vector generated would work
directly against the ‘‘suspension’’. When the wheel pivoted it would alter the current
contact patch, thus altering the dynamics of the system. Early testing of the platform
using the prototype driver board found this temporary solution unsuitable as it
collapsed after only a short period of operation. The robot was to be used on level