How you steer your rover will have a big impact on its maneuverability.
Some methods of steering are better for high speeds on smooth
roads, others for slow speeds and rough terrain. You will
need to decide which of the steering patterns below is the best match
for your rover.
Car-type steering
Car-type steering is where the wheels can be
turned to point in the direction you want to steer. They
require more complicated mechanics and have a relatively wide
turning radius. They are better on smooth surfaces than other
types of steering.
Front wheel steering (cars and trucks)
Rear wheel steering (forklift)
Skid steering
Skid steering is where the wheels or tracks on one side
stand still while the wheels or tracks on the other side move.
This causes the vehicle to "skid" to one side or the other,
turning it around. Even tighter turns are possible when the
wheels or tracks move opposite directions, allowing the vehicle to turn
around without moving forward or backward.
With tracks: (bulldozer &
tank)
With wheels: (skip loader)
With legs: (robot walker)
Differential drive
Steering with a differential drive is similar to
skid
steering. There are two wheels, each of which is powered
independently by its own motor. One or two non-powered wheels
provide stability and are free to swivel in any direction.
Advantages:
Easy to build, easy to control, and very
maneuverable. A popular choice for Lego rovers.
Disadvantages:
Not as good on rough terrain. It's harder to
get the center of gravity in the right place for maximum power.
Swather
Mindstorms robot
Other methods
Synchro drive (see Building
Robots
with Lego
Mindstorms for an example)