Self-assemble flying robots in flight.

Researchers at the University of Pennsylvania have developed a series of modular flying robots that can autonomously assemble themselves in midair and fly.

In the video above, the robots can be seen hovering near one another and then slowly moving close until magnets attached to each corner of a vehicle's cage quickly snaps them together.

The system, called ModQuad, is just in its early stage of development, but the researchers say they can imagine scenarios where much larger drone systems with such autonomous capability might actually be able to self-assemble over an impassable chasm and create a bridge, for example.

The system is modeled after biological systems like ant or bee colonies, where collective effort can accomplish goals like transporting material or building large structures. Think of army ants that can build bridges to overcome water hazards.