example, if the connection to a ground station is lost, an airborne
UAV needs a system to safely land and shut down without causing any damage or injury. The capacity for autonomous decision
making is something that can only be provided by some sort of
The case for onboard computing is not purely safety-driven.
With the ability to make decisions on its own, or even simply
follow a pre-programmed course using an autopilot algorithm,
autonomous UAVs remove the need for human intervention and
participation in what are otherwise costly and labor-intensive
tasks. As examples, UAVs have been successfully used for crop dusting and for effectively
and safely fighting forest fires, eliminating some
of the cost and safety risks incurred by using
The ability to create intelligent swarms of
UAVs is particularly important, especially in
applications, such as fighting forest fires, due to
the need to lift heavy cargo (water, in this case).
While it is difficult for one UAV to carry heavy
cargo, distributing it over many UAVs is a robust
solution with some serious software requirements. Peer-to-peer, intra-swarm communication
via networked, onboard computers offers better
performance and makes swarms more adaptable
to new situations and challenges than requiring
all UAVs to communicate via a base station.
In any case, all UAVs ultimately require communications capability in order to reach a ground
station and receive instructions.
For long distance applications this is best
achieved using technologies like radio or satellite,
but when working at short range, ubiquitous
technologies like Wi-Fi and Bluetooth are a convenient choice. Small form factor computers are
available with Wi-Fi, Bluetooth, and high-speed
cellular modems built in — making communication between a computer on the ground and a
computer in the air a relatively simple task.
With these communications in place, some of
the very intensive computing tasks can be moved
completely off the UAV onto the ground station
computer, where resources are not as constrained.
Matching onboard demands to onboard resources
Owing to their small size, the resources available on a UAV are
generally constrained. This is significant to onboard computing
for two reasons: very little power is available for a computer to
use because of the battery size on a UAV, and the size of the computer need to be as small as possible in order to conserve power
by minimizing weight. Power electronics, in particular, can be
Kilobot is a thousand robot swarm developed at
Harvard University. (Photo credit: Asuscreative)