Re:The Death and Life of Helicopter Commuting [video]
by sp332 on Friday September 01, 2017 @10:55AM
(#15148811)
Well I don't really know how much torque a helicopter would need. The only number I was able to find was that a 35-foot rotor could spin about 550 RPM. Even with a smaller rotor that would spin somewhat faster, I was guessing that a reasonable gear ratio would give an electric motor plenty of torque at those speeds.
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Re:The Death and Life of Helicopter Commuting [video]
by Gravityloss on Friday September 01, 2017 @11:41AM
(#15149403)
And we are back at square one where the whole point was to go multirotor to avoid the gearbox and cyclic pitch complexity.
In a car, it's a bit similar thing. With a combustion engine it optimizes to a single engine with fixed + variable ratio and shafts to the wheels and things like differentials. Lots of places to have oil, to maintain, to break, being heavy too. Tesla has 1-2 electric motors with a fixed gear ratio of about 10. Some concept vehicles have a direct drive motor near each wheel or even inside the wheel.
The electric motor has different characteristics than a turbine or a piston engine. Hence it can affect the whole machine design.