4 ms·
Two reasons. First, surface area. For an equivalent surface area, one rotor results in a much smaller craft than 4 rotors. Second, precision machining. It i
by jackpirate 14y ago
Two reasons. First, surface area. For an equivalent surface area, one rotor results in a much smaller craft than 4 rotors.
Second, precision machining. It is much easier to balance 1 set of rotors weighing hundreds of pounds than it would be to balance 4 of them. I'm guessing your typical quadcopter is too small right now for this to be a real concern.
- Ao7bei3s 14y agoBalancing props is a very real concern, but for another reason than efficiency: unbalanced props cause more vibration and lead to reduced image/video quality due to the rolling shutter effect (image looks wobbly). That being said, many people don't bother with propeller balancing. Size of the aircraft is a very important point, but there are other reasons besides the two you mentioned. Generally, larger motors are more efficient than smaller ones. Larger, slower, props are more efficient than smaller, faster, ones, because Thrust ~ Rotor Speed^2 but Power ~ Rotor Speed ^ 3. Why? I don't recall, sorry. I'm more interested in the software. (If you do figure it out though, let me know.)
- sopooneo 14y agoBecause KE is proportional to v^2, and then you get another factor of v since the volume (and thus mass) of air through the rotors per unit time is proportional to how fast the air is moving. At least that's my guess. And if I'm right, it's also why, to a first approximation, the power generated by a windmill is proportional to the cube of the wind speed.