
Drones require heavy batteries or lots of electrical components, which leaves little room for the actual payload. A Purdue University team came up with a method to use fluid power technology for autonomous vertical takeoff and landing (VTOL) vehicles.
The fluid power propulsion system uses hydrostatic transmission, a lighter-weight and more reliable option, to distribute engine power throughout the rotors, providing thrust for the aircraft and allowing the rotors to each spin at different speeds.