The coolest thing about Transformers, of course, is that they can take two completely different shapes. Most can be bipedal robots or working vehicles. Some can instead transform into weapons or electronic devices. A Transformer's two forms have vastly different strengths and capabilities.
This is completely different from most real robots, which are usually only good at performing one task or a few related tasks. The Mars Exploration Rovers, for example, can do the following:
An Exploration Rover wouldn't be very good at tasks that don't fit into these categories. It can't, for example, assemble a bridge, fit into very small spaces or build other robots. In other words, it would make a lousy search-and-rescue robot, and it wouldn't fit in at all in an automated factory.
That's why engineers are developing reconfiguring robots. Like Transformers, these robots can change their shape to fit the task at hand. But instead of changing from one shape to one other shape, like a bipedal robot to a tractor-trailer, reconfiguring robots can take many shapes. They're much smaller than real Transformers would be; some reconfiguring robot modules are small enough to fit in a person's hand.
A module is essentially a small, relatively simple robot or piece of a robot. Modular robots are made of lots of these small, identical modules. A modular robot can consist of a few modules or many, depending on the robot's design and the task it needs to perform. Some modular robots currently exist only as computer simulations; others are still in the early stages of development. But they all operate on the same basic principle - lots of little robots can combine to create one big one.
Modules can't do much by themselves. A reconfiguring system also has to have:
- Connections between the modules
- Systems that govern how the modules move in relation to one another
Most modular, reconfiguring robots fit into one of three categories: chain, lattice and modular configuration. Chain robots are long chains that can connect to one another at specific points. Depending on the number of chains and where they connect, these robots can resemble snakes or spiders. They can also become rolling loops or bipedal, walking robots. A set of modular chains could navigate an obstacle course by crawling through a tunnel as a snake, crossing rocky terrain as a spider and riding a tricycle across a bridge as a biped.
Examples of chain robots are Palo Alto Research Center's (PARC) Polybot and Polypod and NASA's Snakebot. Most need a human or, in theory, another robot, to manually secure the connections with screws.