2008

Quadrotor

If you look in Google Trends, no one searched for the word “quadrotor” prior to 2007. In 2007 there is a little blip. And then people start searching for it in earnest in 2008. This documents the birth of the quadrotor—a four-rotor helicopter—in public consciousness.

The modern quadrotor is made possible by a set of engineering advancements in the model airplane industry. Small, powerful neodymium magnet motors are essential to quadrotors. So are lightweight, inexpensive lithium polymer batteries, and precise motor controllers that feed battery power to the motors. And then there is the computer control system plus the new sensors that automatically stabilize the four-propeller platform.

Those elements all came together around 2008. Then, in 2010, the Parrot Company in France engineered a model priced at $300 that allowed for mass consumption of quadrotors when it appeared on the cover of Brookstone’s catalog.

The quadrotor represents a major engineering reconceptualization of the helicopter, which had remained nearly unchanged in any major aspect since its invention in the 1930s. Instead of a single engine with rotor and swash plate plus a tail boom, the quadrotor uses four motors and four static propellers. The relative speed of the four motors controls the platform’s motion.

Quadrotor control systems rely on inexpensive solid-state gyros, three-axis accelerometers, and clever software engineering. With these sensors, the vehicle can tell when it starts to spin, tip, and wobble—then it automatically corrects things to keep the platform stable. A human tells the stable platform where to go. Or, a computer-controlled quadrotor can have its own GPS unit and fly to a specific position, hover over a known point on earth, or fly from waypoint to waypoint.

Six- or eight-rotor vehicles are possible, allowing for large payloads like studio-quality cameras. An octorotor with camera can replace a helicopter with cameraman, dramatically lowering the cost of aerial shots. These vehicles are also useful for aerial surveillance, emergency response, etc.

Quadrotors are a perfect example of how advancement in several engineering disciplines can come together to create a reconceptualization. The next step will be full human-size vehicles with sixteen or more rotors.

SEE ALSO Helicopter (1944), Neodymium Magnet (1982), Lithium Ion Battery (1991), Global Positioning System (GPS) (1994).

Photo of a Dji Phantom with GoPro in flight taking aerial photos February 09, 2014 in Miami, Florida, USA.