Wheeled robots are robots that move on the ground with the use of their wheels. This design is frequently preferred because it is much simpler than legged designs and design, production and programming processes for moving on flat terrain is easier. Another advantage of wheeled robots is their being easy to control than other robot types. These robots cannot pass obstacles and this is the main disadvantage of this type. Because of that these robots are almost useless in terrains that are not flat and have low friction coefficient. Wheeled robots can have various numbers of wheels, but for static and dynamic stability, three wheels are enough.
The main reason for preferring a wheeled robot design is its simple locomotion mechanism. Wheeled robots can use different locomotion methods depending on their number of wheels. Generally two wheeled robots control their heading by differential steering method. This method is applicable to not only three wheeled, but also four wheeled robots. Besides differential steering method, four wheeled robots can implement car like steering methods. Similar to four wheeled robots, multi wheeled robots can implement both differential steering and car like steering methods.
Omni wheeled robots and single wheeled robots act like unicycles or balls have their own locomotion methods.