A shape-shifting chembot, also called a liquid robot or a chemical robot, is a mobile robot that can alter its shape and other physical characteristics to do things that it could not do in its normal form.
In late March 2007, DARPA submitted a request for proposal ( RFP ), seeking plans for a chembot. Their specifications: "soft, flexible, mobile objects that can identify and manoeuvre through openings smaller than their static structural dimensions."
Significant properties of chembots include the following:
- Flexibility in three dimensions
- The ability to break apart and reform
- Support of autonomous or remotely controlled modes
- Ability to withstand extremes of temperature, pressure, humidity and radiation
- Flexible external "skin" that can withstand stress without rupturing
- Backbone structure that allows reconstitution to original physical shape and dimensions
- Tactile sensing
- Ability to carry hard and soft payloads without damaging them or being damaged by them.
If realized, such a chembot could travel over considerable distances carrying an embedded payload , change shape and size as required, and then reconstitute to its original form. The DARPA document likens the proposed abilities of the chembot to characteristics already displayed in nature: "Many soft creatures, including mice, octopi, and insects, readily traverse openings barely larger than their largest 'hard' component." The branch of science involving technological developments that mimic natural phenomena is known as biomimetics .
Potential applications for chembots include space exploration, military operations and medical devices that can be implanted in the human body. Chembots might also prove useful for rescue operations in hostile environments such as subterranean or undersea mines and caves.