Quadrotor Drones

Note: The fleet of drones was not given a specific name so I just called it Quadrotor drones.

Searching lost hikers in the middle of thick forest can be very challenging and may cause further danger to rescuers. These drones can address those challenges and can save lives. These were developed by researchers from the Massachusets Institute of Technology (MIT) in collaboration with the NASA Langley Research Center.

The drones collaboratively search for lost hikers without the need for GPS. They can explore terrain or thick canopies using wireless communication.

Each autonomous quadrotor drone is equipped with laser-range finders for position estimation, localization, and path planning. As the drone flies around, it creates an individual 3-D map of the terrain. Algorithms help it recognize unexplored and already-searched spots, so it knows when it’s fully mapped an area.
_{[Source: Product page]}

Watch this video to see how it works: