I'm working on a design project and am trying to power spherical wheels to make them move in all directions. it also could do with being a fairly small set up if possible. can anyone help?
I assume you mean any direction on a surface? A hemispherical cap fitted to the top of the spherical wheel, with two sets of drive motors embedded in the cap might do it. You'd have to set the drive motors on gimbals so they could be rotated in a plane tangent to the sphere, and there you'd have it!
It's tough to do without pictures, but maybe I was clear enough to get you started?
It's tough to do without pictures, but maybe I was clear enough to get you started?
I think one spherical drive wheel set in a hemispherical hub, with one cylindrical power wheel would do it. Just make the power wheel capable of lifting off the surface of the drive wheel, rotating at least 90° and reversing direction.
Uhhh? What would hold the wheel in the cap? (other than gravity)
One good bump and the cap rebounds up and off of the wheel.
One good bump and the cap rebounds up and off of the wheel.
QUOTE (paul h+Feb 28 2008, 04:49 PM)
Uhhh? What would hold the wheel in the cap? (other than gravity)
One good bump and the cap rebounds up and off of the wheel.
Make the cap slightly more spherical than a hemisphere, as with all other such devices. (I have a book light that works that way.)
One good bump and the cap rebounds up and off of the wheel.
Make the cap slightly more spherical than a hemisphere, as with all other such devices. (I have a book light that works that way.)
Got it. 
Take the rollers out of a mouse and replace them with motors. It's a simple design that can be modified and scaled up if needed. For instance in a larger set up, you'll probably want a main ball that weighs less than the vehicle...
Whatever design you choose, remember that just like an old mouse, dust/dirt is your worst enemy.
Whatever design you choose, remember that just like an old mouse, dust/dirt is your worst enemy.
Gerbils. But remember to put air holes in the spheres.
QUOTE (Corvidae+Feb 28 2008, 07:15 PM)
Whatever design you choose, remember that just like an old mouse, dust/dirt is your worst enemy.
That's partially why I mentioned a mechanism to raise/lower the power wheel, and to use only one power wheel which rotates, rather than two.
You can seal off the mechanism which controls the power wheel easier that way, and you can make the friction between it and the drive wheel much stronger, so the drive wheel can only spin in the direction of desired travel, instead of freely along whatever axis wasn't being used, currently.
I'm getting ideas about this... It's an idea I've thought of myself, but never really looked into... I could draw up some specs in autocad, and test out the physics (not very well, but well enough I think for a proof of concept) in 3ds.
I can do the maths needed for engineering the device well enough for a proof of concept too, I think...
g_cameron, are you interested in that kind of help?
That's partially why I mentioned a mechanism to raise/lower the power wheel, and to use only one power wheel which rotates, rather than two.
You can seal off the mechanism which controls the power wheel easier that way, and you can make the friction between it and the drive wheel much stronger, so the drive wheel can only spin in the direction of desired travel, instead of freely along whatever axis wasn't being used, currently.
I'm getting ideas about this... It's an idea I've thought of myself, but never really looked into... I could draw up some specs in autocad, and test out the physics (not very well, but well enough I think for a proof of concept) in 3ds.
I can do the maths needed for engineering the device well enough for a proof of concept too, I think...
g_cameron, are you interested in that kind of help?
I'm a new guy, so I need to learn the ropes, but I do have a question.
It's a neat idea, but where would it be used? Or is that the secret part you're not going to tell us?
Caner
It's a neat idea, but where would it be used? Or is that the secret part you're not going to tell us?
Caner
QUOTE (Resha Caner+Feb 29 2008, 06:23 PM)
I'm a new guy, so I need to learn the ropes, but I do have a question.
It's a neat idea, but where would it be used? Or is that the secret part you're not going to tell us?
Caner
On the bottom of a vehicle.
It's a neat idea, but where would it be used? Or is that the secret part you're not going to tell us?
Caner
On the bottom of a vehicle.
Aren't you funny.
There's the "gee, that's cool" aspect for techno-geeks. But what advantage does it have over that stone wheel discovered by cave men?
I mean, we're living a cliche' here: reinventing the wheel.
There's the "gee, that's cool" aspect for techno-geeks. But what advantage does it have over that stone wheel discovered by cave men?
I mean, we're living a cliche' here: reinventing the wheel.
I played with this idea a long time ago. The problem is braking. Without positive braking from speed you have no hope. Sorry.
By the way, my initial concept used compressed air to hold the shell(and vehicle) up AND to propell the spheres in any direction. With modern control mechanisms it would work quite well. The spherical "tires" would have a pronounced tread to help the compressed air gain traction. But without a positive way to stop quickly... no hope.
Sorry, pal.
By the way, my initial concept used compressed air to hold the shell(and vehicle) up AND to propell the spheres in any direction. With modern control mechanisms it would work quite well. The spherical "tires" would have a pronounced tread to help the compressed air gain traction. But without a positive way to stop quickly... no hope.
Sorry, pal.
Braking is not a problem.
The brakes make contact with the drive wheel (the spherical one), through the use of a standard hydrolic system. Instead of squeezing a pad, it simply compresses portions of the inner walls of the housing around the drive wheel.
I'm going to go ahead and draw something up in autocad, then post screenshots. It might take me a few days, though.
Almost all of the same advantages that a car tire has over "that stone wheel."
Plus the advantage of almost never loosing traction, no matter how the vehicle tilts, turns or spins.
The brakes make contact with the drive wheel (the spherical one), through the use of a standard hydrolic system. Instead of squeezing a pad, it simply compresses portions of the inner walls of the housing around the drive wheel.
I'm going to go ahead and draw something up in autocad, then post screenshots. It might take me a few days, though.
QUOTE
But what advantage does it have over that stone wheel discovered by cave men?
Almost all of the same advantages that a car tire has over "that stone wheel."
Plus the advantage of almost never loosing traction, no matter how the vehicle tilts, turns or spins.
While Spherical Wheels may not be so good for automotive applications due to difficulties in absorbing shock moments of rough road surfaces at high speeds, I think they would be great for tunnel crawlers or in the micro world to navigate through the blood stream.
QUOTE (paul h+Mar 2 2008, 01:05 PM)
While Spherical Wheels may not be so good for automotive applications due to difficulties in absorbing shock moments of rough road surfaces at high speeds, I think they would be great for tunnel crawlers or in the micro world to navigate through the blood stream.
That's actually the problem he's going to run in to if he takes this full size.
At full vehicle size the tires will have to be extremely squishy to deal with road shock at high speed, they'll also need to be very rigid in order to be grabbed by any kind of braking system.
It's a built in contradiction that's really hard to work around. Small scale stuff can get around this by not caring about shock or quick stops. Once you get up to a one ton plus vehicle, things aren't so forgiving.
That's actually the problem he's going to run in to if he takes this full size.
At full vehicle size the tires will have to be extremely squishy to deal with road shock at high speed, they'll also need to be very rigid in order to be grabbed by any kind of braking system.
It's a built in contradiction that's really hard to work around. Small scale stuff can get around this by not caring about shock or quick stops. Once you get up to a one ton plus vehicle, things aren't so forgiving.
QUOTE (Corvidae+Mar 3 2008, 09:38 AM)
At full vehicle size the tires will have to be extremely squishy to deal with road shock at high speed, they'll also need to be very rigid in order to be grabbed by any kind of braking system.
That was an issue with the normal wheel, as well.
The same solution would apply to a spherical wheel as to a cylindrical one.
The solution is to mount the entire assembly on a spring/strut & damper assembly.
That was an issue with the normal wheel, as well.
The same solution would apply to a spherical wheel as to a cylindrical one.
The solution is to mount the entire assembly on a spring/strut & damper assembly.
BDM,
>The solution is to mount the entire assembly on a spring/strut & damper assembly.
Yes for sure but, there is an over abundance of engineering problems with high speed Spherical Wheels. "Squishy" tires must be used to maintain road traction but, how to mount them to a rim? Without a rim a semi-ridged tire would have to be too stiff to absorb road shocks or if soft enough to absorb micro moments and inertia changes it will deform too much and cause overloading of the wheel support rollers (bearings) This will lead to a problem with friction/ware,, Not having a conventional cone/cup bearing the shock moments will not pass thru to the shock absorbers easily but will spike in the wheel support socket and will cause un-wanted drag and ware on the tires. balancing the wheel is another problem altogether. Tread design is also a problem. the tire must have some type of tread design to reduce the chance of a hydroplane. But how to orient the tread pattern when the omni-directional nature of a Spherical Wheel will change with every turn or change of direction. tread design may not be so much of a problem but the grooves will carry dirt and road crud up into the wheel socket. Now should we discuss brakes? Magnets under the rubber tire and windings in the socket to make an electro magnetic brake would be the only way to prevent excessive ware on the tires from friction. But this goes back to how to mount the tire on a round rim.
Most all of these problems may be over come with a magnetic levitation / propulsion / braking design.
>The solution is to mount the entire assembly on a spring/strut & damper assembly.
Yes for sure but, there is an over abundance of engineering problems with high speed Spherical Wheels. "Squishy" tires must be used to maintain road traction but, how to mount them to a rim? Without a rim a semi-ridged tire would have to be too stiff to absorb road shocks or if soft enough to absorb micro moments and inertia changes it will deform too much and cause overloading of the wheel support rollers (bearings) This will lead to a problem with friction/ware,, Not having a conventional cone/cup bearing the shock moments will not pass thru to the shock absorbers easily but will spike in the wheel support socket and will cause un-wanted drag and ware on the tires. balancing the wheel is another problem altogether. Tread design is also a problem. the tire must have some type of tread design to reduce the chance of a hydroplane. But how to orient the tread pattern when the omni-directional nature of a Spherical Wheel will change with every turn or change of direction. tread design may not be so much of a problem but the grooves will carry dirt and road crud up into the wheel socket. Now should we discuss brakes? Magnets under the rubber tire and windings in the socket to make an electro magnetic brake would be the only way to prevent excessive ware on the tires from friction. But this goes back to how to mount the tire on a round rim.
Most all of these problems may be over come with a magnetic levitation / propulsion / braking design.
QUOTE (paul h+Mar 4 2008, 09:29 AM)
BDM,
>The solution is to mount the entire assembly on a spring/strut & damper assembly.
Yes for sure but, there is an over abundance of engineering problems with high speed Spherical Wheels. "Squishy" tires must be used to maintain road traction but, how to mount them to a rim? Without a rim a semi-ridged tire would have to be too stiff to absorb road shocks or if soft enough to absorb micro moments and inertia changes it will deform too much and cause overloading of the wheel support rollers (bearings) This will lead to a problem with friction/ware,, Not having a conventional cone/cup bearing the shock moments will not pass thru to the shock absorbers easily but will spike in the wheel support socket and will cause un-wanted drag and ware on the tires. balancing the wheel is another problem altogether. Tread design is also a problem. the tire must have some type of tread design to reduce the chance of a hydroplane. But how to orient the tread pattern when the omni-directional nature of a Spherical Wheel will change with every turn or change of direction. tread design may not be so much of a problem but the grooves will carry dirt and road crud up into the wheel socket. Now should we discuss brakes? Magnets under the rubber tire and windings in the socket to make an electro magnetic brake would be the only way to prevent excessive ware on the tires from friction. But this goes back to how to mount the tire on a round rim.
Most all of these problems may be over come with a magnetic levitation / propulsion / braking design.
Good point...
Mounting the tire to a rim would not be difficult... There are currently available foams which take the place of pressurized air inside a tire, thus allowing the manufacture of tires which are "married" to the rims... This would be expensive, but definitely do-able.
The issue would come with the warping of the flexible tire, which could cause lock-ups, if it compressed too much. I suppose the only real solution to that issue would be to find the right balance of "squshiness" and rigidity, while keeping the housing at just the right size to prevent lock-ups from a compressed tire, while still holding the spherical wheel in place. I don't know that this proper balance could be found, but it seems to me like such is possible...
Tread wouldn't be too much of an issue, provided the power wheel was encased to prevent dirt and debris from jamming up it's workings... Same with the brakes, which would be a bit trickier. (Come to think of it, there would be an issue with the braking system I described, if the tires were too soft. But once again, the trick is in finding the right balance.) The tread pattern could be a simple diamond pattern, similar to that on tractor tires, but symmetrical (as opposed to the elongated tread of tractor tires.)
It seems to me like the shock absorption system of the entire wheel assembly would account for much of the bumpiness of the ride, which in turn would make finding the balance between soft & rigid tires possible, but I haven't done enough math to know for sure. I'll be doing some work on the design tonight, so I should have some drawings and math to post tomorrow, if all goes well.
I'm not convinced that it's possible. I AM convinced that it's worth looking into.
Keep thinking of problems, please It makes my job so much easier, not having to figure them out or discover them unexpectedly myself 
>The solution is to mount the entire assembly on a spring/strut & damper assembly.
Yes for sure but, there is an over abundance of engineering problems with high speed Spherical Wheels. "Squishy" tires must be used to maintain road traction but, how to mount them to a rim? Without a rim a semi-ridged tire would have to be too stiff to absorb road shocks or if soft enough to absorb micro moments and inertia changes it will deform too much and cause overloading of the wheel support rollers (bearings) This will lead to a problem with friction/ware,, Not having a conventional cone/cup bearing the shock moments will not pass thru to the shock absorbers easily but will spike in the wheel support socket and will cause un-wanted drag and ware on the tires. balancing the wheel is another problem altogether. Tread design is also a problem. the tire must have some type of tread design to reduce the chance of a hydroplane. But how to orient the tread pattern when the omni-directional nature of a Spherical Wheel will change with every turn or change of direction. tread design may not be so much of a problem but the grooves will carry dirt and road crud up into the wheel socket. Now should we discuss brakes? Magnets under the rubber tire and windings in the socket to make an electro magnetic brake would be the only way to prevent excessive ware on the tires from friction. But this goes back to how to mount the tire on a round rim.
Most all of these problems may be over come with a magnetic levitation / propulsion / braking design.
Good point...
Mounting the tire to a rim would not be difficult... There are currently available foams which take the place of pressurized air inside a tire, thus allowing the manufacture of tires which are "married" to the rims... This would be expensive, but definitely do-able.
The issue would come with the warping of the flexible tire, which could cause lock-ups, if it compressed too much. I suppose the only real solution to that issue would be to find the right balance of "squshiness" and rigidity, while keeping the housing at just the right size to prevent lock-ups from a compressed tire, while still holding the spherical wheel in place. I don't know that this proper balance could be found, but it seems to me like such is possible...
Tread wouldn't be too much of an issue, provided the power wheel was encased to prevent dirt and debris from jamming up it's workings... Same with the brakes, which would be a bit trickier. (Come to think of it, there would be an issue with the braking system I described, if the tires were too soft. But once again, the trick is in finding the right balance.) The tread pattern could be a simple diamond pattern, similar to that on tractor tires, but symmetrical (as opposed to the elongated tread of tractor tires.)
It seems to me like the shock absorption system of the entire wheel assembly would account for much of the bumpiness of the ride, which in turn would make finding the balance between soft & rigid tires possible, but I haven't done enough math to know for sure. I'll be doing some work on the design tonight, so I should have some drawings and math to post tomorrow, if all goes well.
I'm not convinced that it's possible. I AM convinced that it's worth looking into.
Keep thinking of problems, please
It makes my job so much easier, not having to figure them out or discover them unexpectedly myself
Hi All, BDW, Paul,
I would see 2 prob's right off. First, isn't more surface area just more drag?
And, with the way people drive now, do we really want that kind of bumper car control on a highway!
Peace,
Ron
I would see 2 prob's right off. First, isn't more surface area just more drag?
And, with the way people drive now, do we really want that kind of bumper car control on a highway!
Peace,
Ron
BDW,
Something to think about:
Strut angle and length. If these two could be adjusted on the fly, you could for example move the center of gravity of the unit in a curve to a more desirable location. IE: in a sharp left hand curve the struts could move the body over to the left and lower on that side. Slower speed the body could raise higher with a narrower foot print. Higher speed the body could be lower and have a wide foot print.
No coments about the magnetic levitation / propulsion / braking design?
Something to think about:
Strut angle and length. If these two could be adjusted on the fly, you could for example move the center of gravity of the unit in a curve to a more desirable location. IE: in a sharp left hand curve the struts could move the body over to the left and lower on that side. Slower speed the body could raise higher with a narrower foot print. Higher speed the body could be lower and have a wide foot print.
No coments about the magnetic levitation / propulsion / braking design?
QUOTE (Ron+Mar 4 2008, 01:37 PM)
Hi All, BDW, Paul,
I would see 2 prob's right off. First, isn't more surface area just more drag?
And, with the way people drive now, do we really want that kind of bumper car control on a highway!
Peace,
Ron
Ron,
You are right,, this is an engineering nightmare.
(for the application discussed here) But sure it could be done, Would it be better or worse? I don't know but I do know that it would be far more expensive.
I would see 2 prob's right off. First, isn't more surface area just more drag?
And, with the way people drive now, do we really want that kind of bumper car control on a highway!
Peace,
Ron
Ron,
You are right,, this is an engineering nightmare.
(for the application discussed here) But sure it could be done, Would it be better or worse? I don't know but I do know that it would be far more expensive.
QUOTE (paul h+Mar 4 2008, 01:53 PM)
BDW,
Something to think about:
Strut angle and length. If these two could be adjusted on the fly, you could for example move the center of gravity of the unit in a curve to a more desirable location. IE: in a sharp left hand curve the struts could move the body over to the left and lower on that side. Slower speed the body could raise higher with a narrower foot print. Higher speed the body could be lower and have a wide foot print.
No coments about the magnetic levitation / propulsion / braking design?
I hadn't thought of that, but it's a damn good idea. You could even use the struts to aid in braking (the momentum as they moved forward would slightly slow down the momentum of the vehicle) provided they weighed enough.
As for the magnetic propulsion, braking, levitation idea: It's a good idea, but do you think we could generate the kind of power needed to get useful results from a power supply that could be mounted on the vehicle? It seems to me like the power needed to do everything magnetically would simply make the whole project too expensive (or perhaps even impossible, I don't know.) to be feasible.
Something to think about:
Strut angle and length. If these two could be adjusted on the fly, you could for example move the center of gravity of the unit in a curve to a more desirable location. IE: in a sharp left hand curve the struts could move the body over to the left and lower on that side. Slower speed the body could raise higher with a narrower foot print. Higher speed the body could be lower and have a wide foot print.
No coments about the magnetic levitation / propulsion / braking design?
I hadn't thought of that, but it's a damn good idea. You could even use the struts to aid in braking (the momentum as they moved forward would slightly slow down the momentum of the vehicle) provided they weighed enough.
As for the magnetic propulsion, braking, levitation idea: It's a good idea, but do you think we could generate the kind of power needed to get useful results from a power supply that could be mounted on the vehicle? It seems to me like the power needed to do everything magnetically would simply make the whole project too expensive (or perhaps even impossible, I don't know.) to be feasible.
but do you think we could generate the kind of power needed to get useful results from a power supply that could be mounted on the vehicle?
no,,, but only because we haven't invented it yet,,,
(How,s that for positive thinking)?
no,,, but only because we haven't invented it yet,,,
(How,s that for positive thinking)?
alright guys all this advice is great. I wouldnt even of known where to start.
The whole spherical drive wheel thing is just part of what im needing to do so if anyone can help with the rest it would be great.
I'm designing a set of tables which slide underneath one and other. there would be one table which would remain static then two tables which slide underneath. What i'd ideally like to happen is have the two smaller tables with the motors in them. Then they would be pulled out and used as side tables for a cup of coffee etc. After the cup, for example, is removed from the surface the tables would then begin to slowly move back together and slide back underneath the static table.
i dont know if i've bitten off more than i can chew. i've got someone that says they can help with programming but i need help with the components. Any advice anyone can offer will be greatly appreciated.
cheers
The whole spherical drive wheel thing is just part of what im needing to do so if anyone can help with the rest it would be great.
I'm designing a set of tables which slide underneath one and other. there would be one table which would remain static then two tables which slide underneath. What i'd ideally like to happen is have the two smaller tables with the motors in them. Then they would be pulled out and used as side tables for a cup of coffee etc. After the cup, for example, is removed from the surface the tables would then begin to slowly move back together and slide back underneath the static table.
i dont know if i've bitten off more than i can chew. i've got someone that says they can help with programming but i need help with the components. Any advice anyone can offer will be greatly appreciated.
cheers
In that case, why use wheels at all? Drawer slides and linear actuators are off-the-shelf stuff now, no need to reinvent the wheel... 
yeah but im talking about them being moved to the other side of the room and not necessarily being in line with the static table.
Ah, I thought you were talking car sized or highway speeds for those wheels. Coffee table sized is a lot more doable. You could use something like a racquetball with a miniature pool ball inside of it for the wheels and some off the shelf electric motors to drive it. Braking is as simple as stopping the motors, and once the table is in place it could simply tighten a band around the wheels to lock them in place.
The subject spherical wheels reminds me of something I was thinking about 10 years ago. That was a sphere with tyre read with a 360 by 360 degree spinning motor with a remote control device. The device starts rolling in whatever direction you remote control it. The tyer-tread spherical motor works by rolling in the opposite direction to the angular inertia spin of the accelerating mass of the motor in the center. A billiard ball size version of the device could perform some impossible billiards maneuvers on the table with a giggling prankster remote controlling it.
I have idea. A Spherical Wheel propped by normal wheel on top that can rotate on a axis. By rotating the normal the wheel to point in different direction spherical wheel will spin in defferant direction. Traction is issue .
But wounld be better to just have wheels that each rotate in 360 dergees.
Are you starting with the nopower kind and go from there?
But wounld be better to just have wheels that each rotate in 360 dergees.
Are you starting with the nopower kind and go from there?
QUOTE (thunder8+Mar 29 2008, 04:55 PM)
I have idea. A Spherical Wheel propped by normal wheel on top that can rotate on a axis. By rotating the normal the wheel to point in different direction spherical wheel will spin in defferant direction. Traction is issue .
But wounld be better to just have wheels that each rotate in 360 dergees.
Are you starting with the nopower kind and go from there?
Looks like you were a little late...
But wounld be better to just have wheels that each rotate in 360 dergees.
Are you starting with the nopower kind and go from there?
Looks like you were a little late...
QUOTE (BIGDUMBWEIRDO+)
I think one spherical drive wheel set in a hemispherical hub, with one cylindrical power wheel would do it. Just make the power wheel capable of lifting off the surface of the drive wheel, rotating at least 90° and reversing direction.
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