5 ms·
Doesn’t a flywheel resist changes in direction like a gyroscope?
by erik_seaberg 4y ago
Doesn’t a flywheel resist changes in direction like a gyroscope?
- pfdietz 4y agoLess of a problem if the axis of the flywheel is vertical.
- ragebol 4y agoThen steering becomes more difficult.
- pfdietz 4y agoWhy would that happen? Rotation of the vehicle around an axis parallel to the axis of the flywheel will cause no gyroscopic effects.
- toxik 4y agoTo better understand the intuition here, imagine you spin a really heavy bike wheel on an axle held horizontally between your hands. It would be easy to spin the axle, which is the equivalent of turning the car here. To be clear I’m agreeing with you.
- userbinator 4y agoYes, although I'm not sure how much that effect would be noticeable in the systems discussed.
- omginternets 4y agoI imagine they’re placed parallel to the ground, which would have the additional benefit of reducing body roll during turns.
- JKCalhoun 4y agoHa ha, could cause you to nose down (or up) though. Rotational physics is weird.
- toxik 4y agoNo, if the rotation is coaxial the cross product is near zero. Torque T, ang vel w, ang acc a T = w cross a
- JKCalhoun 4y agoBut as the body attempts to roll going into the turn, the gyroscope will respond longitudinally I believe.
- toxik 4y agoThat’s right, but it wouldn’t be a very large torque, I don’t think. Especially since the roll is resisted by the spring damped suspension and the sway bar. The resulting force would pitch the car up/down depending on turn direction and flywheel direction.
- thfuran 4y agoOr you could slap a brake on it for instant left-hand turns.
- omginternets 4y agoPresumably you’d have two counter-rotating disks.
- thfuran 4y agoSo you can have instant right-hand turns too. Nice.
- omginternets 4y agoWell, no, since you have two equal masses rotating in opposite directions... EDIT: Oh, I see what you're saying. I thought you were talking about the oppsite direction: hit brakes, and car turns. You're instead talking about putting a caliper on each disk, and snapping the car left/right. Oh man, that would be fun ^^
- WalterBright 4y agoYes. That's why a flywheel car will stay level when ascending a hill.
- loa_in_ 4y agoSounds like a bonus, if only for axle to axle differential 4 wheel drive
- dredmorbius 4y agoTwinned counterrotating gyros cancel one another. Added weight and complexity. Another option is a gimbal mount, though that makes any mechanical coupling more difficult, and requires more space. For electrically driven / driving flywheels, it's an option however.
- qubex 4y agoA friend of mine built a small model vehicle that implemented dual gyroscopes as an energy storage medium for an electric vehicle as part of his PhD. One of the gyros seized and the whole thing flipped and slammed into the ground with tremendous force.
- dredmorbius 4y agoGyros offer interesting learning curves. Which are often tangential.
- radu_floricica 4y agoReading the article I guessed this is why they end up used in busses and other larger vehicles.