Helicopters and slopes do not go well together. Blade strike is one unpleasant possibility and ground resonance—where the rotor develops severe vibration—is another hazard.
The US military’s Defence Advanced Research Projects Agency, (DARPA) recently gave an experimental demonstration of their Robotic Landing Gear for helicopters. The system consists of four articulated, jointed automated legs that fold up next to the helicopter’s fuselage while in flight. Each leg has an integrated force-sensitive contact sensor in its foot. During landing, each leg extends and the sensor determines in real time the appropriate angle to assume to ensure that the helicopter stays level without risking the rotor touching the landing area.
The Georgia Institute of Technology is developing the Robotic Landing Gear with funding from DARPA.
DARPA program manager Ashish Bagai says the demonstration flight indicated numerous potential benefits. This includes:
- Reduced risk of damage during hard landings, by as much as a factor of five compared to conventional landing gear.
- Stable landing and take-off on sloping terrain of up to 20 degrees (more than twice current limits), and on craggy, boulder-strewn or otherwise irregular terrain.
- Ship landings in violent sea states.
- Significant increase in capabilities with only a modest increase in landing gear weight.
More information on the robotic landing gear can be found on DARPAs website.