121–130 of 149 posts
The response could be a closer approximation of linear by using six tubes, two magnets each, with varying initial distances. As the stick compresses, additional magnets contribute force, but not all at once.
[+- +-> ===== As long as the open-wide distance is capped you should have a smoother distance-energy diagram.
Earlier quoted context omitted.
About as scary as my Tesla on autopilot going around a curve at 75mph. Every time I ask myself, what if there is a bug or if it turns off...
I know exactly what you mean. I will admit at 20mph over the speed limit going over a poorly maintained curve on the Mass Pike I usually just disengage for a moment and then switch it back on. It can take the curve, but it doesn’t feel good to let it. I’ve had it lose tracking on the highway. It just leaves the wheel in the last position and beeps very urgently to let you know to take over. I find autopilot helps me…
They factor how far a head you can see, and how much time you need to react. Lots of cars/bikes can obviously tear through them faster. But that means they are just taking much more risk.
That said, perhaps auto driving can respond quicker, but I’d imagine that doesn’t change most of those ratings give. The time needed to avoid accidents is largely due to physics not reaction speed.
> For the 4, 5 and 6 magnet stacks, the outermost gaps tended to be a bit larger than the inner gaps. Why? > As we add more magnets to the stack, the maximum pull force alternates up and down. If 2 magnets repel with some force, 3 is a little less, but 4 is a little more 3, but 5 is a little less than 4, etc. Why is this so? Shouldn't these guys have figured it out pretty easily? Both seem to be readily explained by…
You could try A BC D, AB CD, AB C DE and A BCD E.
Seems like electromagnets could help compensate for distance by drawing more current when far apart, and less when close together. A microcontroller could essentially make the force linear like a spring. Of course, then you need wires hooked up to your pogo, and that might be scary if the microcontroller has a bug (or somehow fails) since you are now essentially hopping onto a railgun.
Not only that, but you can adjust the “springiness” by having a variable spring constant.
If you really wanted to do this, I reckon the way would be to have one set of magnets on the moving shaft and another set surrounding it, so the the repulsion tends to keep the shaft centered. Then you make the shaft surround taper towards the top, so that the further the pole is pushed in, the closer together the magnets are forced. You should be able to achieve any force curve desired with this setup by making the…
I think you're making things too difficult and expensive if you're trying to magnetically suspend and stabilize the pogo stick in multiple/all directions.
Also, magnetic radial stabilization would be stable only in a rough sense. The pogo stick handle would still wobble and be disturbingly/unexpectedly unsteady. I think for pogo sticks you'd really want a mechanically confined, piston-like design. You could still have magnetic stops on both extremes.
I’ve often thought it might be interesting to replace the springs in a piano’s action with electromagnets so you could have control over the exact touch profile.
I don’t think pianos typically have any springs, everything is gravity powered with counterweights. The only springiness comes from striking the strings as far as I know. Only the really cheap electronic keyboards use springs. Even halfway decent electronic pianos still rely on counterweights.
Keys itself return into their normal position because of gravity, but part of key action mechanism was powered by a spring. I discovered it while trying to fix some keys which was too slow to "recharge", to return to a normal position after a soft note, so I was unable to make a sequence of a short duration soft notes from the same key. I fixed it by stretching springs long enough for a plastic deformation to occur. Loud notes worked ok, because their "recharge" was driven fully by springness of the strings.
Though it was just one piano, I do not know how different the mechanics can be between different pianos.
If you really wanted to do this, I reckon the way would be to have one set of magnets on the moving shaft and another set surrounding it, so the the repulsion tends to keep the shaft centered. Then you make the shaft surround taper towards the top, so that the further the pole is pushed in, the closer together the magnets are forced. You should be able to achieve any force curve desired with this setup by making the…
Just use current designs which, I would think, mechanically constrain the pogo stick except in one direction. Replace spring with powerful magnet (pair), and make sure there's a stop pin or something similar to keep the magnetic pogo stick from disassembling itself. I think you're making things too difficult and expensive if you're trying to magnetically suspend and stabilize the pogo stick in multiple/all directions…
Another advantage of my design is that it allows (requires, in fact) one to use many small magnets in place of a few large ones, which is safer and easier to engineer. But as for expense - I think that once you decide to replace springs with magnets in a pogo stick, you have left the path of economy anyway and might as well go for broke.
Unsurprisingly, an inverse-square mechanism can't replace a linear one over a wide working range.
I wonder if there’s a Fourier transform equivalent that’d let you stack up various inverse square curves to appropriate a linear curve?