Molecular robots have been fabricated by supramolecular chemists, chemical and biomolecular engineers, and nanotechnologists. This multi-disciplinary approach has led to the development of methods to let these robots interact and work together in swarming millions.
(Molecular robots in useful swarms)
Toward this end, researchers have made molecular robots with three key components: microtubules, single-stranded DNA, and a light-sensing chemical compound. The microtubules act as the molecular robot's motor, converting chemical energy into mechanical work. The DNA strands act as the information processor due to its incredible ability to store data and perform multiple functions simultaneously. The chemical compound, azobenzene derivative, is able to sense light, acting as the molecular robot's on/off switch...
A continuing challenge, though, is making separate groups of robots swarm at the same time, but in different patterns. This is needed to perform multiple tasks simultaneously. One group of scientists achieved this by designing one DNA signal for rigid robots, sending them into a unidirectional bundle-shaped swarm, and another DNA signal for flexible robots, which simultaneously rotated together in a ring-shaped swarm.
"Robot sizes have been scaled down from centimeters to nanometers, and the number of robots participating in a swarm has increased from 1,000 to millions," write the researchers.
Science fiction writer Stanislaw Lem imagined and described systems in which millions of minute robots swarmed in purposeful ways in his 1954 novel The Invincible:
I believe them to be very tiny pseudo insects that, if necessary, and for their common good, can unite to form a superordinate system. This is the course taken by the evolution of the mobile mechanisms."