An engineering professor and a team of developers at the Oregon State University-Cascades have created a prototype of a hybrid engine for smaller unmanned aerial systems. This innovative development may change the way small drones are manufactured as well as improve their battery capacity.

Small drones are usually limited by their battery power, but with this new hybrid engine, the on board battery can now be recharged with gasoline allowing the vehicles to stay up for a longer period.  OSU-Cascades assistant professor, Chris Hagen and the team of developers scaled down the idea and opened up new potentials for hybrid engines that will weigh less than 55lbs.

Mark Peters, the research compliance coordinator at OSU stated that Dr. Hagen took a concept that is viable for larger drones and miniaturizes it for smaller drones. With this new technology, the functionality of small UAS can be extended for search and rescue as well as other activities that are limited by a drone’s battery power.

Previously, Dr. Hagen developed a natural gas-powered engine that could compress natural gas. This lead to the formation of Onboard Dynamics, a company that commercialized the project. Southern California Gas Co. partnered with Onboard Dynamics to manufacture the engine and promote it as a more efficient means of powering natural-gas-fueled school buses.

But this new development is in a league of its own. The research and development began two years ago, stated Hagen. Although the technology already existed in smaller component parts, the trick was to put it all together and make sense of it all.  Development was not easy and integration ended up being a lot more difficult than Hagen had expected. The team worked hard to integrate all the different parts that existed to use just the right amount of energy, as well as outputting the exact amount of power needed.

The team included a group of undergraduates, graduate students, and former colleagues. They bought a German-made engine (3W28i) usually used in radio-controlled aircraft. It is a small, one-cylinder, two-stroke engine that produced 2.75hp. The engine was used to power a generator, which charged the batteries that ran the electric motors connected to a drone’s propellers. Although the idea sounds simple, several attempts were made to get this to work before, Hagen said.

He also stated that they got the UAS to fly for over an hour and 3 minutes. Others who have made this claim do not have documented proof. The Oregon team has been working on this research for a few years now and have flown 5-6 times longer than the best battery powered drones.  Mark Peters stated that the hybrid system was displayed at the Oregon UAS Summit and Expo early last month in Bend and that it attracted the attention of several prospective users. The next possible action would be to get the interest of the National Science Foundation, the U.S. Defense Department or any other organizations that can help advance the technology, Peters said.