Most man-made vehicles today travel on wheels and for good reason: wheels are much easier to construct and control. In today's economy, they also tend to be much cheaper than their legged counterparts. However legs have distinct advantages over wheels. The biggest advantage is in transversability and efficiency. Legged robots have a unique ability to:
Isolate their body from terrain irregularities
-Avoid undesirable footholds
-Regulate their stability
-Achieve energy efficiency : Features : These advantages are very desirable in modern robotics, and therefore a lot of research is being put into creating robots that can walk. The most challenging task in designing a legged robot is to create a system that can generate the proper gait
A system on four legs is another walking scheme found readily in nature. Four legged robots have the advantage of being statically stable when not moving, but require dynamic walking control. There are many different ways for a four legged robot to walk including alternating pairs and opposite pairs as in six legged robots. However these techniques now cease to be statically stable and thus require dynamic control.$ Disclaimer : Product colour may slightly vary due to photographic lighting sources
