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Nearly every kind of surface vehicle in common use has wheels. While the earliest known vehicles had skids, and some of these designs are still in use today, wheels are so ubiquitous that little or no thought is given to the modern corollary of wheels, namely, paved roads.
This is a complex economic issue. Roads that last a long time, providing a smooth enough surface for comfortable and rapid vehicular movement, are enormously expensive. The only other kind of useful alternative today are tracks, often enough made of steel, whose construction and maintenance is also enormously expensive.
However, there is an obvious alternative to wheels, which is to mimic nature. Apart from the locomotion of very tiny creatures, that move by flexing their bodies, all larger creatures that move on land use legs. The singular major exception to this rule is snakes.
Pedal vehicles, vehicles with legs, have been, in the last couple of decades, a really well known art object. Pioneered by the Dutch artist Theo Janssen Theo Jansen - Wikipedia, the family of Strandbeest have been entertaining and intriguing visitors for years. Many are wind powered, some use feedback sensors, such as the presence of water, to decide the direction of travel.
Another potential use is for exoplanetary land rovers, given the uncertainty of potential terrain to explore. And Boston Dynamics, an American R&D venture Boston Dynamics | Boston Dynamics, has developed several very high performance robotic vehicles (extremely expensive, though), that emphasise the use of legs (and, in some cases, hands).
Is there scope for the construction of practical commonplace human or load carriers that use legs instead of wheels?
What are the main considerations that dictate a successful design?
What are the potential power sources?
What modern materials lend themselves to creating such vehicles?
What other questions need to be asked while venturing on creating such designs, not just for a Maker Lab, but for production?
In the HBCSE Maker Lab, one vehicle was built a couple of years back, whose leg mobility followed the Theo Janssen model. In fact, there are several web sites that offer reasonably well described blueprints for making such devices, which can be found with videos on YouTube as well as in text.
Further thought has distilled some practical ideas for drive mechanisms, using commonplace materials. They will be developed in the near future. More ideas are welcome.