. Such an arrangement needs a two degree-of-freedom (DOF) suspension for the
vertical and lateral tilting motion of the wheel. In this paper modeling, simulation, design and
experimentation with a three-wheeled mobile robot, with torus-shaped wheels and a novel
two DOF suspension allowing independent lateral tilt and vertical motion, is presented. The suspension
is based on a four-bar mechanism and is called the double four-bar (D4Bar) suspension.
Numerical simulations show that the three-wheeled mobile robot can traverse uneven terrain
with low wheel slip. Experiments with a prototype three-wheeled mobile robot moving on a constructed
uneven terrain along a straight line, a circular arc and a path representing a lane change,
also illustrate the low slip capability of the three-wheeled mobile robot with the D4Bar
suspension.