Complicated enough it seems where they can’t agree. Yep… crashing on the ice though was due to trying to turn. As a young experienced ice cyclist myself I can say a person doesn’t just wipeout the instant you run across a patch of ice. An endless pastime of mine was riding my bike with no hands, one can turn slightly or adjust by tilting the body. In fact you are better off if you went fairly fast with no hands into the ice. Ever try to ride a bike slow? Why does speed make it easier? Why riding without your hands and going faster seem better at stability with gravel or curbs if it isn’t resisting change?
Sure get out there and experiment yourselves on going slow or trying to turn on ice. Just remember, only one thing hurts more than falling on ice and that is getting the horizontal bar in the nuts. Go ahead but just remember let it all out; howl at the moon from the pain down in the warm the cockles of your gonads.
Landgraf Karl von Hessen-Kassel
Moderator: scott
re: Landgraf Karl von Hessen-Kassel
What goes around, comes around.
re: Landgraf Karl von Hessen-Kassel
"Ice-biking", was multiple decades ago... never attempted (*cough* dared) the no-hands variant on ice.
"Ever try to ride a bike slow? Why does speed make it easier?" - I suspect that that putting it in low-gear, and paddle a bit faster makes it easier and faster to compensate your own reverse-pendulum effect... ?
--
Here's another rotation currently under investigation, nice and dry..
Not sure yet if it relates to bicycle tires or has other "uses of interest".
Dzhanibekov motion.
https://www.youtube.com/watch?v=r-TnCMZF3fA
A T-shape rotates slightly off-center around the horizontal X-axis.
Avoiding the common formula's (see wiki). I hypothesize that off-center rotation causes a centrifugally induced force on the axis of rotation.
Because rotation is off-center, there is no opposite to provide a centripetal force to keep a rotating weight at the distance from the rotational axis.
As a result this centrifugal give a moment-force around the CoM perpendicular to the axis of rotation. Like adding force to a balance-lever. This results in a torque on the system. This 'flip'-rotation ramps up until it rotates around its smallest Moment of Inertia while this T-shape is at its maximum flip. Then this 'flip'-torque reverses and slows 'flip'-rotation while this T-shape moves to the other side.
This is just preliminary: I have yet to correlated this result with the standard equations - but I'm happy it shows the flip-effect when just considering Centrifugal.
See also: https://en.wikipedia.org/wiki/Tennis_racket_theorem
"Ever try to ride a bike slow? Why does speed make it easier?" - I suspect that that putting it in low-gear, and paddle a bit faster makes it easier and faster to compensate your own reverse-pendulum effect... ?
--
Here's another rotation currently under investigation, nice and dry..
Not sure yet if it relates to bicycle tires or has other "uses of interest".
Dzhanibekov motion.
https://www.youtube.com/watch?v=r-TnCMZF3fA
A T-shape rotates slightly off-center around the horizontal X-axis.
Avoiding the common formula's (see wiki). I hypothesize that off-center rotation causes a centrifugally induced force on the axis of rotation.
Because rotation is off-center, there is no opposite to provide a centripetal force to keep a rotating weight at the distance from the rotational axis.
As a result this centrifugal give a moment-force around the CoM perpendicular to the axis of rotation. Like adding force to a balance-lever. This results in a torque on the system. This 'flip'-rotation ramps up until it rotates around its smallest Moment of Inertia while this T-shape is at its maximum flip. Then this 'flip'-torque reverses and slows 'flip'-rotation while this T-shape moves to the other side.
This is just preliminary: I have yet to correlated this result with the standard equations - but I'm happy it shows the flip-effect when just considering Centrifugal.
See also: https://en.wikipedia.org/wiki/Tennis_racket_theorem
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Marchello E.
-- May the force lift you up. In case it doesn't, try something else.---
-- May the force lift you up. In case it doesn't, try something else.---
re: Landgraf Karl von Hessen-Kassel
What goes around, comes around.
re: Landgraf Karl von Hessen-Kassel
Hey dax .. seems pretty clear to me ;) A little gyroscopic force but not much influence. That can be taken out of the equation with counter rotating wheels on a floor motorised roller system so that the bike is stationary but wheels are turning fast.
The trail keeps the wheel turning in the direction of lean (lowered CoM) which then 'bites' and the bike and riders inertia kicks it upright again (inertia). This can be done with riderless bikes as well.
Overall I would wager that when a bike leans over lowering its CoM, and the wheel turns, and tire friction bites, and the CoM rises again, that the linear bike speed (KE) is reduced by the same amount that the CoM is raised in GPE. So each correction leads to a bleeding of speed.
Begs the question tho. If we lean over and the CoM drops and then we autocorrect to raise the CoM then this is like a pendulum with no net loss of GPE. But we do get frictional heat losses from tire and road, moving parts, and windage etc.
The trail keeps the wheel turning in the direction of lean (lowered CoM) which then 'bites' and the bike and riders inertia kicks it upright again (inertia). This can be done with riderless bikes as well.
Overall I would wager that when a bike leans over lowering its CoM, and the wheel turns, and tire friction bites, and the CoM rises again, that the linear bike speed (KE) is reduced by the same amount that the CoM is raised in GPE. So each correction leads to a bleeding of speed.
Begs the question tho. If we lean over and the CoM drops and then we autocorrect to raise the CoM then this is like a pendulum with no net loss of GPE. But we do get frictional heat losses from tire and road, moving parts, and windage etc.
re: Landgraf Karl von Hessen-Kassel
Yes, I believe you are right Fletcher myself. I would really like to get on the stationary bike to see if I notice any difference in effect than riding a real bike.
https://www.youtube.com/watch?v=Sm9j0S_dCZ0
https://www.youtube.com/watch?v=Sm9j0S_dCZ0
What goes around, comes around.
re: Landgraf Karl von Hessen-Kassel
What goes around, comes around.
re: Landgraf Karl von Hessen-Kassel
Perhaps indeed more difficult than it looks... :-)
Video of the Delft-investigation by the co-author of the paper, saying that they removed the trail [8:50] : https://www.youtube.com/watch?v=2Y4mbT3ozcA
While twiddling with a disc, here my evolved new-and-improved hypothesis:
I was thinking that a rolling disc on itself is reasonably self-stabilizing too: a disc could be a flat iron disc - basically (or almost) countering my earlier friction-talk.
When a disc steers sideways from its current path then the translational momentum of the disc still tries to keep this thing moving in the original direction. What will happen is that a turned disc seems to look oval-shaped when the axis of rotation points slightly in the direction of motion. With the bottom of the disc on its edge, the top of the disc keeps moving (translationally) and moves ahead of the center of mass. With the center of mass no longer above the point of contact, the disc (while rotating) tries to drop to the ground, but in the opposite direction of that initial steering direction (like a coin running circles) and thereby turning upright again --I still think friction helps enormously here as a thicker disc is simply more stable (you need to raise the CoM for unbalance) than an thinner disc no matter what Moments of Inertia--
Yet with more weight as a whole, like an attached bike-frame and the rider, there's simply more linear momentum to push the wheel back in the direction of motion and so improves that stabilization process and keep a straight path, especially when there's another wheel (behind) in the direction of motion to keep things moving.
Without enough speed the amount of momentum is not enough to make a wheel fall over its center of mass and therefore keeps dropping in the turned direction. So there should be a minimum speed where you can lean-steer a bike ... and live.
Video of the Delft-investigation by the co-author of the paper, saying that they removed the trail [8:50] : https://www.youtube.com/watch?v=2Y4mbT3ozcA
While twiddling with a disc, here my evolved new-and-improved hypothesis:
I was thinking that a rolling disc on itself is reasonably self-stabilizing too: a disc could be a flat iron disc - basically (or almost) countering my earlier friction-talk.
When a disc steers sideways from its current path then the translational momentum of the disc still tries to keep this thing moving in the original direction. What will happen is that a turned disc seems to look oval-shaped when the axis of rotation points slightly in the direction of motion. With the bottom of the disc on its edge, the top of the disc keeps moving (translationally) and moves ahead of the center of mass. With the center of mass no longer above the point of contact, the disc (while rotating) tries to drop to the ground, but in the opposite direction of that initial steering direction (like a coin running circles) and thereby turning upright again --I still think friction helps enormously here as a thicker disc is simply more stable (you need to raise the CoM for unbalance) than an thinner disc no matter what Moments of Inertia--
Yet with more weight as a whole, like an attached bike-frame and the rider, there's simply more linear momentum to push the wheel back in the direction of motion and so improves that stabilization process and keep a straight path, especially when there's another wheel (behind) in the direction of motion to keep things moving.
Without enough speed the amount of momentum is not enough to make a wheel fall over its center of mass and therefore keeps dropping in the turned direction. So there should be a minimum speed where you can lean-steer a bike ... and live.
Marchello E.
-- May the force lift you up. In case it doesn't, try something else.---
-- May the force lift you up. In case it doesn't, try something else.---
re: Landgraf Karl von Hessen-Kassel
Yeah ME .. rolling coins and hoops are good examples of staying upright without trailing etc (still need friction). I kinda like your new improved theory. Sounds a lot like a spinning top explanation to me. I'm still guessing that any drop in CoM from a lean will bleed translation KE from the disk when auto-uprighting takes place balancing the sums ?
I wonder if there are vids around showing disks etc near the transition speed when a coin or hoop starts to wobble and turn but still auto-corrects to upright ? That boundary condition might shed some light.
I wonder if there are vids around showing disks etc near the transition speed when a coin or hoop starts to wobble and turn but still auto-corrects to upright ? That boundary condition might shed some light.
-
Georg Künstler
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re: Landgraf Karl von Hessen-Kassel
why not ? think on a segway.
https://de.wikipedia.org/wiki/Segway_Pe ... ransporter
Auto correction by software, to fail not forward.
As I said, the software and mathematics is there, it is used in the wrong way.
In the Segway it serves for stabilization.
We need exactly the opposit for our wheel.
see also:
https://science.howstuffworks.com/trans ... inger1.htm
https://de.wikipedia.org/wiki/Segway_Pe ... ransporter
Auto correction by software, to fail not forward.
As I said, the software and mathematics is there, it is used in the wrong way.
In the Segway it serves for stabilization.
We need exactly the opposit for our wheel.
see also:
https://science.howstuffworks.com/trans ... inger1.htm
Best regards
Georg
Georg
re: Landgraf Karl von Hessen-Kassel
Sure, such idea may totally replace daxwc's (I presume, I don't know) amazing multi-million-dollar handlebar-technology for NON Cirque-du-Soleil clowns.
Who would have thought Perpetual motion is exorcized by an incantation in the form of a mathematical sign-issue, and easily circumvented by flipping a logical bit?
Unfortunately, any kind of (already commonly used) motorized reverse-pendulum mono/solo/uni-cycle, which is able to do the balancing-trick without human control, still needs a source of energy to enable such control! Software may be great, but is not *that* great. (A recurring overlooked nuisance so it seems).
The mathematics of physics may seem to look like a trick sometimes, and tricky otherwise. Yet no-one is stopping you from simply ignoring those "rules of engagement" when you're going to build your stuff. The maths are simply there to make life and communication easier - not more restrict: But ignoring it shouldn't result in a Universe which suddenly works/acts differently -- Perhaps it does, who knows.
The fun is in wondering about the how&why of bare wheels and bikes going with enough speed and to be able to balance by their own intrinsic nature, and then hope to discover some benefits.
The disappointment is when one therefore expects that the seat of an unicycle will be balanced along with it... and discover reality only after the leap.
I really hope those handle bars are also able to handle these kinds of pain.
Rolling discs:
https://www.youtube.com/watch?v=o5m7bNziVLg
Who would have thought Perpetual motion is exorcized by an incantation in the form of a mathematical sign-issue, and easily circumvented by flipping a logical bit?
Unfortunately, any kind of (already commonly used) motorized reverse-pendulum mono/solo/uni-cycle, which is able to do the balancing-trick without human control, still needs a source of energy to enable such control! Software may be great, but is not *that* great. (A recurring overlooked nuisance so it seems).
The mathematics of physics may seem to look like a trick sometimes, and tricky otherwise. Yet no-one is stopping you from simply ignoring those "rules of engagement" when you're going to build your stuff. The maths are simply there to make life and communication easier - not more restrict: But ignoring it shouldn't result in a Universe which suddenly works/acts differently -- Perhaps it does, who knows.
The fun is in wondering about the how&why of bare wheels and bikes going with enough speed and to be able to balance by their own intrinsic nature, and then hope to discover some benefits.
The disappointment is when one therefore expects that the seat of an unicycle will be balanced along with it... and discover reality only after the leap.
I really hope those handle bars are also able to handle these kinds of pain.
Rolling discs:
https://www.youtube.com/watch?v=o5m7bNziVLg
Marchello E.
-- May the force lift you up. In case it doesn't, try something else.---
-- May the force lift you up. In case it doesn't, try something else.---
re: Landgraf Karl von Hessen-Kassel
LOL; joking aside although when I think about turning a bike at a fair speed
a person doesn’t just yank the handle bars over to pull out of it, you move your COM back. The slower the bike is going the more effort it takes to do that, but I don’t see a crumb of free energy there because speed on exit decreases also the energy needed to accerate to that speed in the first place. I can’t see that effect ever having enough power of Bessler’s wheel. Just my opinion though I was wrong a couple of times before while trying to get in that clown car at the rodeo.
a person doesn’t just yank the handle bars over to pull out of it, you move your COM back. The slower the bike is going the more effort it takes to do that, but I don’t see a crumb of free energy there because speed on exit decreases also the energy needed to accerate to that speed in the first place. I can’t see that effect ever having enough power of Bessler’s wheel. Just my opinion though I was wrong a couple of times before while trying to get in that clown car at the rodeo.
What goes around, comes around.