Discussion about "how do I ride a bike" on the "bicycle design and engineering" LinkedIn group.
Andrew Dressel
How Do I Ride a Bike?
Solid-state gyroscopes and position sensors are part of a lot of phones and E-pads of various sorts. A suitable app for such a device might generate signals comparable to the information from the semi-circular canals of the inner ear.
What is needed is some way to send the information to the brain, possibly by small electrodes or vibrating pads on the earlobes or the scalp.
It does depend, of course, on whether the balance problem originates with the semi-circular canals or with the part of the brain that processes the inputs.
If the processing is okay, the brain should adapt quite quickly to signals from another source. A lot of balance information already comes from other sources, such as our feet and our vision, so we are not asking the brain to do something unprecedented.1 day ago
Innovative solution John for using a alternate reference source!
I have experienced vertigo when flying over the sea at night and the visual reference to aircraft's Artificial Horizon was enough to re-establish my positional orientation. The concept of using an alternate reference source to confirm or establish stability has merit.20 hours agoThe artificial horizon is a great example, Carl.
When I am holding the bike still, such as when preparing for a steep and rutted descent, even holding a thin outer branch of a tree can help because I can feel any lateral movement through my fingers faster than through other senses.14 hours agoJohn....I have also had that same experience. I would guess it is one of the reason many people use canes to walk because it provides that same type of tactile reference.
10 hours agoYes, indeed, Carl.
Another point I am making, though, with both the adjustable-resistance bankable sidecar and with the external reference source, is that it is reasonable to expect some recovery of balance; and that we can assist that recovery, rather than entirely substitute for whatever ability remains.8 hours ago
Get a 20" Strider which is light and purely simple to redevelope your balance again.
44 minutes ago
As attractive as it may first appear, it is not clear that adding additional wheels in some way (either with a trike, sidecar, or training wheels) might be able to facilitate the ability to "ride, maybe race, a conventional bicycle."
To do so, a three-or-more-wheel design would have to still allow and require countersteering, just less so, perhaps with slower response times and/or lower gains.
On one end of the spectrum, with additional wheels rigidly attached, countersteering simply does not work, of course, and so such a contraption should be expected to facilitate no improvement in the ability to ride a bicycle.
On the other end of the spectrum, with additional wheels spring-loaded so as to perfectly counter the roll moment created by gravity acting on the leaning mass, turning simply does not work. See ruina.tam.cornell.edu/research/topics/bicycle_mechanics/brike_paper18.pdf
So then the trick is to find or create a design that allows for countersteering but that somehow has lower requirements for it. Can anyone point to such a design that already exists?
My own experience with adjusting the a semi-stable a tilting trike (www.jetrike.com) is that riders are confused by the combination of mechanically enforced stability and the continued requirement to countersteer. Perhaps we just didn't find the sweet spot.36 minutes ago- Like(0)
- Delete
One approach that I don't think we've touched on yet is steer-by-wire. I know of at least one steer-by-wire bicycle, at TU Delft, but haven't yet read if they've looked into whether it can help someone who is unable to balance a conventional bicycle.
Anyone else have an information on this angle?
(Oh, and I meant to write "my own experience with adjusting the semi-stabilty of a tilting trike...." above)25 minutes ago- Like(0)
- Delete
I don't think this last solution would help in balancing the bike...
The gyrobike is instead really interesting!
Maybe coupled with a fatbike or a 27+ is a good compromise between fun to drive and helping driving10 minutes agoVery interesting, Andrew. Thanks for digging it up.
I have long wondered about the steering of the old Renault Dauphine that used spring pressure to assist in centring the steering. Seemed to me it would feel weird. Has anyone driven one, and can comment?
As the authors point out, however, "The arguments precluding control are heavily dependent on the linearity of the system, and the non-linear inverted pendulum in zero gravity seems to be controllable." I was not thinking of spring systems linear to the pull of gravity so I think the answer remains inconclusive.7 minutes ago
Bill Semenoff
Andy Ruina
Hi:
After June 13 or so I'd be happy to Skype with anyone who wants to about these things. I have no quick
easy response to the posting below.
From:
"st...@googlegroups.com" <st...@googlegroups.com> on behalf of Bill Semenoff <billse...@gmail.com>
Reply-To: "st...@googlegroups.com" <st...@googlegroups.com>
Date: Wednesday, May 31, 2017 at 4:42 PM
To: "st...@googlegroups.com" <st...@googlegroups.com>
Subject: [stvdy] Re: Discussion about "how do I ride a bike" on the "bicycle design and engineering" LinkedIn group.
I'm working on a design similar to the Brike. I have to confess it's been a few years since I did any coursework in control theory, but my thoughts after reading the paper are that the assumption of a sinusoidal springback response being optimal was never really questioned. Also that the Whipple model is an oversimplification for this problem. It would be interesting if someone developed a more realistic bicycle model by adding one or more hinges to account for the ability to trackstand (or lack of that ability if I understand the original poster's problem).
We know (anecdotally) how this is done with modern conventional bikes and wouldn't it seem to require an additional hinge at the wrists ?
Robert
On Monday, July 6, 2015 at 8:20:14 AM UTC-7, Andrew Dressel wrote:
I don't know of a good way to connect these two groups, but thought this discussion taking place there might be thought provoking here.
Mark Harrison likes this
See previous comments
·
Solid-state gyroscopes and position sensors are part of a lot of phones and E-pads of various sorts. A suitable app for such a device might generate signals comparable to the information from the semi-circular canals of the inner ear.
What is needed is some way to send the information to the brain, possibly by small electrodes or vibrating pads on the earlobes or the scalp.
It does depend, of course, on whether the balance problem originates with the semi-circular canals or with the part of the brain that processes the inputs.
If the processing is okay, the brain should adapt quite quickly to signals from another source. A lot of balance information already comes from other sources, such as our feet and our vision, so we are not asking the brain to do something unprecedented.1 day ago
·
Innovative solution John for using a alternate reference source!
I have experienced vertigo when flying over the sea at night and the visual reference to aircraft's Artificial Horizon was enough to re-establish my positional orientation. The concept of using an alternate reference source to confirm or establish stability has merit.20 hours ago
·
The artificial horizon is a great example, Carl.
When I am holding the bike still, such as when preparing for a steep and rutted descent, even holding a thin outer branch of a tree can help because I can feel any lateral movement through my fingers faster than through other senses.14 hours ago
·
John....I have also had that same experience. I would guess it is one of the reason many people use canes to walk because it provides that same type of tactile reference.
10 hours ago
·
Yes, indeed, Carl.
Another point I am making, though, with both the adjustable-resistance bankable sidecar and with the external reference source, is that it is reasonable to expect some recovery of balance; and that we can assist that recovery, rather than entirely substitute for whatever ability remains.8 hours ago
·
Get a 20" Strider which is light and purely simple to redevelope your balance again.
44 minutes ago
·
As attractive as it may first appear, it is not clear that adding additional wheels in some way (either with a trike, sidecar, or training wheels) might be able to facilitate the ability to "ride, maybe race, a conventional bicycle."
To do so, a three-or-more-wheel design would have to still allow and require countersteering, just less so, perhaps with slower response times and/or lower gains.
On one end of the spectrum, with additional wheels rigidly attached, countersteering simply does not work, of course, and so such a contraption should be expected to facilitate no improvement in the ability to ride a bicycle.
On the other end of the spectrum, with additional wheels spring-loaded so as to perfectly counter the roll moment created by gravity acting on the leaning mass, turning simply does not work. See ruina.tam.cornell.edu/research/topics/bicycle_mechanics/brike_paper18.pdf
So then the trick is to find or create a design that allows for countersteering but that somehow has lower requirements for it. Can anyone point to such a design that already exists?
My own experience with adjusting the a semi-stable a tilting trike (www.jetrike.com) is that riders are confused by the combination of mechanically enforced stability and the continued requirement to countersteer. Perhaps we just didn't find the sweet spot.36 minutes ago
o Like(0)
o Delete
·
One approach that I don't think we've touched on yet is steer-by-wire. I know of at least one steer-by-wire bicycle, at TU Delft, but haven't yet read if they've looked into whether it can help someone who is unable to balance a conventional bicycle.
Anyone else have an information on this angle?
(Oh, and I meant to write "my own experience with adjusting the semi-stabilty of a tilting trike...." above)25 minutes ago
o Like(0)
o Delete
·
I don't think this last solution would help in balancing the bike...
The gyrobike is instead really interesting!
Maybe coupled with a fatbike or a 27+ is a good compromise between fun to drive and helping driving10 minutes ago
·
Very interesting, Andrew. Thanks for digging it up.
I have long wondered about the steering of the old Renault Dauphine that used spring pressure to assist in centring the steering. Seemed to me it would feel weird. Has anyone driven one, and can comment?
As the authors point out, however, "The arguments precluding control are heavily dependent on the linearity of the system, and the non-linear inverted pendulum in zero gravity seems to be controllable." I was not thinking of spring systems linear to the pull of gravity so I think the answer remains inconclusive.7 minutes ago
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It was actually the clarity from the Modelling Mick exercise that made me foolhardy enough to attempt the Naro.
Damian
Andy Ruina
Damian:
I don't know who you are or where you are so don't know how to write to you. Might you chat on Zoom with me
some time? You can write to me outside the group.
— Andy Ruina, Mechanical Engineering, Cornell
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