Wheel with integrated suspension

[manchild]

This is about something I’ve patented about a year ago. I have offered it to major car manufacturers who analyzed/tested it, confirmed functionality but said that they can’t apply it on current products/passenger cars having in mind overall financial & production issues (Daimler-Chrysler, V.A.G, GM, Renault, PSA, BMW…).

The reason I’m posting it here is to get opinions about possibility to apply this design on F1 and other racing cars. Also, I’d like to hear opinions and suggestions regarding materials.

I know that there are synthetic non-metallic fiber springs and obviously rest of the wheel could be made of exotic materials? What about rim, magnesium or could it be CF reinforced with Kevlar? Any suggestion for material for connecting axles, steel or possibly something synthetic?
...
Here is the presentation;




1.Rim
2.Spring
3.Central element
4.Bearing
5.Connecting axle
6.Shock absorber & spring pole
7.Shock absorber

Pole that consist form shock absorber & spring are connecting rim with the central element by connecting axles on both of their ends.

This enables the change of angle of poles and functioning of shock absorbers and springs (stretching-compressing).

Maximal change of poles angle is limited by stiffness of springs or by dimension of openings in central element.

Ability of the rim of the wheel to change its position in relation to the central element that is mounted on vehicles axle, enables 360 degrees absorption and amortization.

First of all it enables equal absorption of bumps and impacts regardless on angle or direction of obstacle - 360 degrees!



All conventional suspensions are usually designed only for single direction force absorption, while all other impacts are transmitted to vehicles tires, bearings, chassis and bodywork without any absorption.



Secondary advantages of this invention come from its genuine design. Due to specific position and connection between its elements, two completely opposite but highly desirable functions come to life.

During starts and accelerations, inner elements of this wheel act partly as typical ASR system, absorbing torque trough springs and dampers which prevents wheel from sliding in absence of proper grip.



Other function comes also from same elements as the first one.
This time only, during braking, rim of the wheel transmits input torque coming from vehicles inertia to shock absorbers and springs, preventing blocking of the wheel in certain amount and therefore acting partly as typical ABS system.



Basic design of this wheel consists from three-pole system and can be upgraded with as many poles as necessary, depending on vehicles demands and purpose. It can be used with elements of conventional suspensions or without them. In this second case, axle on which the wheel is mounted is attached to the chassis of the vehicle without any elements of conventional suspension. This wheel can be produced as rim-only without any rubber layer, with solid rubber layer or as conventional rim designed for pneumatics.

Y shaped pipeline could be implemented to connect the cylinders of shock absorbers and provide smoother rotation by equalizing the pressure. Simplest way to avoid use of hydraulic or gas shock absorbers could be use of simple bump rubbers where the short suspension travel is necessary or in cases where this design would be used simply to replace pneumatics.

[DaveKillens]

I like it, the principles seem valid.
But ... all these parts are integrated into the actual wheel. I see three major problems. First off, all those suspension parts are much more exposed than if they were located in the traditional position, in the bodywork. Much higher risk of damage or just exposure to dirt and other crap. And if one wheel is broken, the costs would be much higher.
Secondly, this is a lot of extra unsprung weight. That would definitely have a negative effect on the vehicle suspension characteristics. Although, on a true active suspension, this obstacle can be overcome.
Additionally, I suggest it would be a very difficult task to quickly change wheels with this design.
Third, this principle may already be copyright, because in principle, it is very similar to the Mars rover wheels. There are spiral "spokes" and the spaces between the "spokes" are filled with an elastic material.
http://hobbiton.thisside.net/rovermanual/
[img]Side%20view%20of%20Rocker-Bogie%20suspension%20system%20on%20MER[/img]

[DaveKillens]

Addditionally, the torque, from either braking or acceleration will wind the shocks full open or closed. That would be catastrophic, especially under braking conditions.

[manchild]

First off, all those suspension parts are much more exposed than if they were located in the traditional position, in the bodywork. Much higher risk of damage or just exposure to dirt and other crap. And if one wheel is broken, the costs would be much higher.

The outer side of the wheel can be covered up to 100% while the inner side can be covered too partly not fully. I didn’t draw wheel covers for they’re irrelevant for patent application.

Secondly, this is a lot of extra unsprung weight. That would definitely have a negative effect on the vehicle suspension characteristics. Although, on a true active suspension, this obstacle can be overcome.

Weight depends on materials that would be used for its production and if pneumatics would be used on it or just a solid rubber layer. That is why I posted this here, to get opinion and suggestion about materials that can be used to reduce the weight of the wheel to minimum.

Additionally, I suggest it would be a very difficult task to quickly change wheels with this design.

Why?! The openings for bolts aren’t shown on the drawings for they’re also irrelevant for patent application. There could be one single opening for mono bolt in the middle of central element or 3 or more of them in usual circular pattern. The drawing is not a scale model but only showing principle of design. Replacement is the least problem…

Third, this principle may already be copyright, because in principle, it is very similar to the Mars rover wheels. There are spiral “spokes” and the spaces between the “spokes” are filled with an elastic material.

There are couple other designs registered worldwide but the most similar one has 18 elements more that mine. I think that simplicity is very important.

Addditionally, the torque, from either braking or acceleration will wind the shocks full open or closed. That would be catastrophic, especially under braking conditions.

You obviously haven’t checked the drawings carefully and read the description. This system works, I have written confirmations from patent office and from research labs of biggest car manufacturers...

Torque wouldn't open shock absorbers fully for their stretching is limited by openings in central element. When the torque reaches its peek shock absorber’s cylinder leans on widest position of opening of central element and that prevents torque to open up shock absorber fully.

Just as it is done at conventional suspensions simple rubber element can be added to absorb the impact (when the suspension is fully stressed/beyond its capabilities) either on shock absorber cylinder or on each side of openings in central element on which the suspension/shock absorber would lean against ones it reaches maximum angle or rotation.

Once again I have to mention that these rubber elements aren’t shown on drawings also because just as the previous ones they’re irrelevant for patent application.

Don’t forget also that the wheel is loaded with vehicles weight so that also limits motion/rotation of the shock absorber/spring poles.

Perhaps I should mention that spring on unloaded wheel wouldn’t “dance” up and down the shock absorber but they’d be under pressure – made longer than what is the maximal space between their bearings when the shock absorber is fully opened.

[RH1300S]

It's great to see interesting ideas! First, I'm no engineer - so forgive my observations if I miss something obvious to someone with better (any!) training.

Un-sprung weight and rotational intertia were the first things to spring to mind (of course you save the mass of the tyre sitting a long way out from the centre of rotation).

Would the centrifugal force (is it centrifugal or centripetal?) affect the way the damper works, so far damper engineers have not had to think about that problem!

Does the wheel rate depend on spring/damper position? I.e. if a spring/damper is facing directly down, does this imply a different rate to that produced when at an angle (I can't figure out the relationship between the other springs sharing the load).

Would it not be hard to separate bump & rebound damping for chassis tuning as the damper rods are always moving at the same speed relative to each other and are inter-related.

Obviously the wheel diameter limits the potential travel - but this would not be a problem with most vehicles.

How about side loads, how will the dampers deal with these as they seem to be bearing all the side loads in cornering. This puts quite subtantial bending loads into the dampers. Also, even something as simple as adding wheel camber would add some bending load. Like motorbike forks these could cause the dampers to bind under high load, maybe needing very thick tubes and specialist bearing design - but you don't have much damper length inside the wheel to spread out this bending load by letting the tube sit deep in the damper body.

Surely the potential wind-up during acceleration/braking would remove some directness of response from the driver and like bump/rebound damping it would be hard to separate the needs of acceleration/braking to optimise the potential benefits. Also, (sorry to keep thinking of problems!) you would then have the dilemma of whether to tune your springs/dampers to do the suspension duty or control the wind up (this would surely vary dramatically with a car's power to weight ratio/downforce etc.).

Also, how does the "tyre" work now? Is it not true that some of the tyres' ability to grip give feedback is down to the way the carcass allows the contact patch to deform & twist? Obviously the rubber could deform at it's surface, but this seems to me to create the potential for a very "sudden" break away.

I hope you don't think I have just destroyed your idea - it's genuinely interesting....but you did ask

This could be a great idea for off road vehicles..............

[Steven]

I have to agree with RH1300S by noting that this would be the most interesting for off road vehicles.

For motorsports like F1 I think there are a few problems:
- The rules possible do not permit it :p
- There is probably a lack of durability for these things. Note that with this design every spring of the "suspension" extracts and is compressed one during each rotation of the wheel. This may become a real problem compared to current suspension systems where the suspension only moves with a bump or something (whether it be a slow or fast bump doesn't matter).
- Compensation of torque as you describe it will possibly cause problems. Having an engine with great torque and lots of grip there is a need of very very strong inner elements to those springs so that they will not bend off (and eventually break). Current spring and shock absorbers in a suspension do not have to cope with that, only lateral forces on them (so again extra weight).

However as RH1300S said it may well be interesting to see an implementation in some kind of an off road vehicle...

[DaveKillens]

I'm sorry, I cannot visualize nothing but complete disaster in hard braking situations. I visualise the front wheels and it's components. Under hard braking, a tremendous torque is exerted. The "shocks" extend or compress to their allowed travel........ minor bumps occur, and the wheels cannot follow the path along the road surface. Wheel hop, flat spots, definitely very reduced braking ability.
Does anyone know how much torque an F1 brake and wheel assembly can generate? I suspect it is over 1,000 ft/lbs at it's max.
The suspension travel and torque effects of braking or acceleration are not separated in this design, the same components are affected by these forces.
As fas as wheel change problems, I was thinking of a race situation, where time is of the essence, and this wheel assembly has to weigh more than the current models. It's just much more difficult to manhandle.

[RH1300S]

I'm sorry - I think there may be another problem.

The means of attaching the hubs to the chassis......... Currently, the suspension arms can be quite light as some of the work done is being transmitted to the on-board springs/dampers. All they have to do is transmit side force into the chassis and resist the hub rotating as braking loads are fed into it.

With your system, the arms would need to be very stiff is resisting additional vertical loads (right now they can move and the suspension does the work) otherwise the arms become un-damped parts of the suspension as they flex. I can sort of envisage a triangulated structure a bit like a push rod setup; but don't quite see how this would be able to be lighter than now.

Again, this might be less of a problem with something like an off road car; but with F1 you might need a structure that blocks critical air-flow to the rear of the car.

[manchild]

Would the centrifugal force (is it centrifugal or centripetal?) affect the way the damper works, so far damper engineers have not had to think about that problem!

Not for gas dampers I think, hydraulic are out of the question. Did I already mention that damper might consist form nothing more but couple of bump rubbers if used on racing cars?

Does the wheel rate depend on spring/damper position? I.e. if a spring/damper is facing directly down, does this imply a different rate to that produced when at an angle (I can't figure out the relationship between the other springs sharing the load).

Poles are always dealing with forced equally; they compress and stretch, compress and stretch, compress and stretch in circles. When a single pole faces down it will have to compress more than when two poles are down and one pole up…

Would it not be hard to separate bump & rebound damping for chassis tuning as the damper rods are always moving at the same speed relative to each other and are inter-related.

That is up to damper designers and engineers. The true question is how much RPM rotation could this system withstand?

How about side loads, how will the dampers deal with these as they seem to be bearing all the side loads in cornering. This puts quite subtantial bending loads into the dampers. Also, even something as simple as adding wheel camber would add some bending load. Like motorbike forks these could cause the dampers to bind under high load, maybe needing very thick tubes and specialist bearing design - but you don't have much damper length inside the wheel to spread out this bending load by letting the tube sit deep in the damper body.

3 poles is minimum. I was considering that perhaps they’d need to be doubled transversally one next to another.

Surely the potential wind-up during acceleration/braking would remove some directness of response from the driver and like bump/rebound damping it would be hard to separate the needs of acceleration/braking to optimise the potential benefits. Also, (sorry to keep thinking of problems!) you would then have the dilemma of whether to tune your springs/dampers to do the suspension duty or control the wind up (this would surely vary dramatically with a car's power to weight ratio/downforce etc.).

Nobody’s perfect, not even the double wishbones with pushrod

Also, how does the "tyre" work now? Is it not true that some of the tyres' ability to grip give feedback is down to the way the carcass allows the contact patch to deform & twist? Obviously the rubber could deform at it's surface, but this seems to me to create the potential for a very "sudden" break away.

It can be used with elements of conventional suspensions or without them. In this second case, axle on which the wheel is mounted is attached to the chassis of the vehicle without any elements of conventional suspension. This wheel can be produced as rim-only without any rubber layer, with solid rubber layer or as conventional rim designed for pneumatics. .

This means that there are several combinations possible:
1.This wheel with rubber layer only (without pneumatic) on unsuspended/fixed axle
2. This wheel with pneumatic on unsuspended/fixed axle
3. This wheel rubber layer only (without pneumatic) on classic suspension
4. This wheel with pneumatic on classic suspension

I hope you don't think I have just destroyed your idea - it's genuinely interesting....but you did ask This could be a great idea for off road vehicles.............. .

Did send it to Schlesser. No reply yet. I wrote (among other things) – “Imagine Paris-Dakar rally without a puncture..”

I'm sorry, I cannot visualize nothing but complete disaster in hard braking situations. I visualise the front wheels and it's components. Under hard braking, a tremendous torque is exerted. The "shocks" extend or compress to their allowed travel........ minor bumps occur, and the wheels cannot follow the path along the road surface. Wheel hop, flat spots, definitely very reduced braking ability.
Does anyone know how much torque an F1 brake and wheel assembly can generate? I suspect it is over 1,000 ft/lbs at it's max.

No need to appolgize Dave, we’re just debating. Now about extreme breaking situations when the springs are already compressed fully and the bump occurs…

As long as the ABS works properly the springs couldn’t reach the absolute stuck position, they’d have to be pre-calculated for that. Where there is no ABS, s..t would happen but same goes for any conventional suspension. However have in mind that I’m not insisting on single version for all types of vehicles (see quote of my post to RH1300S).

The suspension travel and torque effects of braking or acceleration are not separated in this design, the same components are affected by these forces.

Yes but I believe that this could be advantage - having all unified.

As fas as wheel change problems, I was thinking of a race situation, where time is of the essence, and this wheel assembly has to weigh more than the current models. It's just much more difficult to manhandle.

I imagine F1 car with this system, possibly no pneumatic and absolutely no elements of conventional suspension. Car would weight less and wheels probably a bit more. Regs. Don’t allow this nowadays but ones those to guys leave.. who knows.

The means of attaching the hubs to the chassis......... Currently, the suspension arms can be quite light as some of the work done is being transmitted to the on-board springs/dampers. All they have to do is transmit side force into the chassis and resist the hub rotating as braking loads are fed into it.

Have in mind that I’m not insisting on single version for all types of vehicles (see quote of my post to RH1300S).

With your system, the arms would need to be very stiff is resisting additional vertical loads (right now they can move and the suspension does the work) otherwise the arms become un-damped parts of the suspension as they flex. I can sort of envisage a triangulated structure a bit like a push rod setup; but don't quite see how this would be able to be lighter than now.

Again, this might be less of a problem with something like an off road car; but with F1 you might need a structure that blocks critical air-flow to the rear of the car.

Just as my aero designs this one also need calculations and practical testing by pros and that is something I can’t do on my own.

BTW, I was originaly inquiring about materials, any suggestions?

[RH1300S]

My understanding of gas dampers is that they still have damper fluid (oil) and the gas is used to pressurise the damper - partly as a form of secondary progressive spring and also to reduce aeration of the damper oil.

You can't dismiss the bump/rebound thing as a problem for suspension engineers - your system forces the two to be the same rate. As I see it, there is no way to separate bump from rebound. Damper settings are crucial for making a car behave properly in it's transient responses and to help use the tyres properly.

I see the RPM question as secondary - not the "True Question" (like my comments about damper centrifugal effects really) - these are matters that may or may not be solvable, but don't impact the validity of the concept; which I think the bump/rebound issue may..............

If you overcome the side load problem by adding mass you reduce the potential benefit of the system.

I can see that the un-sprung weight issue changes (may even be quite low?) as the wheel & hub is not moving up and down - just the rim; but also the moving parts of the dampers are moving (all of them in one direction or another).

The rotating mass will go up; and this is a more serious matter as any weight added to a rotating mass (such as wheels/flywheels) has more inertia and takes more energy to accelerate/stop - this would potentially make the car slower. There is an old saying that "a kilo saved on a rotating part is worth ten on the car".

For this reason I don't buy your argument about the overall car weight being the same - just shifting weight to the wheels. What you are doing is shift weight to just exactly where you don't want it. Also I would expect this to increase the polar moment of inertia of the vehicle, just when most F1 designers seem to be doing all they can to reduce it.

The off-road application low performance - like farm/military use would make many of the negatives I have mentioned much less of a problem.

What Dave means (I think I understand him) is that when your dampers lock against the hub in braking/acceleration you no longer have any suspension movement - which is something the tyre does not like and is likely to loose grip over bumps; also the weight transfer to that wheel will be instantaneous (like hitting the bump stops) making the car a bitch to drive on the limit. With a conventional system these things can happen, but you have more control options (ARB's/3rd spring (on some F1 cars)/spring/damper settings/anti dive/squat geometry).

I havn't ignored the fact that you say that your wheel could work with classic suspension - of course it could. It just seems to me that you negate some of the benefits of the scheme - and this time you would add substantial un-sprung weight (again maybe OK for off roaders). In fact this wheel with conventional suspension could give great articulation. How about if the rim between the struts was flexible, you could have an enormous contact patch to climb out of mud holes with (be very odd on the road 'though )

You know, some of the best designs are simple - er.....like the wheel for example - or Colin Chapman using the skin of the car to make a tub as a big bracket in the Lotus 25

[manchild]

The weight is unknown and I agree that using classic materials is out of the question (rotating mass problem). I'm simply imagining 3 shock absorbers cylinders made of synthetic materials including the springs that already can be found made of fiber connected with a rim and central element made of also something exotic CF reinforced with some alloy. The main problem when it matters weight would probably come from connecting axles and rods/inner walls of cylynders in shock absorbers.

Regarding bump and rebound (and the weight too), I see this as a potential problem too but on high RPM, perhaps this can be solved using what Renault introduced in F1 back in the ‘80s – pneumatic valve actuation which would in my case mean use of pressured cylinder instead of spring too (much less weight) . Having a separate pipeline connecting these cylinders to make them have equal pressure. The weight is unknown and I agree that using classic materials is out of the question (rotating mass problem). I'm simply imagining 3 shock absorbers cylinders made of synthetic materials including the springs that already can be found made of fiber connected with a rim and central element made of also something exotic CF reinforced with some alloy. The main problem when it matters weight would probably come from connecting axles and rods/pistons in shock absorbers.

Regarding bump and rebound (and the weight too), I see this as a potential problem too but on high RPM, perhaps this can be solved using what Renault introduced in F1 back in the ‘80s – pneumatic valve actuation which would in my case mean use of pressured cylinder instead of spring too (much less weight) . Having a separate pipeline connecting these cylinders to make them have equal pressure.

I know that there’s some oil to in gas dampers but they are not the same as hydraulic dampers just because of that fact. Gas dampers react much quicker, both ways.

I’m also aiming to simplicity; this wheel is intended to replace the pneumatic, classic suspension, reduce weight of the car, increase free space on chassis and enable 360 degree impact absorption - all in one.

BTW, Monstro – What do you think about aeronautical use? Naturally, I’m thinking on use of my design only as replacement for pneumatics when it matters aeronautics – conventional suspension stays. Can you give us some hints about materials and weight of wheels on passenger airplanes? Weight, dimensions, materials etc. What are the RPM that wheels reach during takeoff/landing? Could this one actually reduce the diameter of the wheel on passenger airplanes for the function of pneumatics would be replaced by shock absorbers and springs (pressured cylinder).

I’m thinking … “no puncture possibility = safety”

[BendR]

First up I love this idea.

It seems similar in concept to the Tweel by Michelin, in my opinion anyway.

I'm wondering if it is possible to have a common gas/fluid reservoir/valve for all the shocks allowing a limiting to the overall speed and sensitivity for the entire system, Similar to Audi's DRC

I agree with most people in that it seems better suited to off roading rather than F1.

[manchild]

I'm wondering if it is possible to have a common gas/fluid reservoir/valve for all the shocks allowing a limiting to the overall speed and sensitivity for the entire system...

Thanks,

I did have that in mind when I mentioned Y shaped pipeline that would connect cylinders and equalize pressures. This pipeline could actually be the reservoir you're mentioning. Pressure could also probably be remotely controlled increased/reduced (added, loosed) if this wheel would be connected to compressor like it is done nowadays.

[RH1300S]

I admit I was thinking as if it was a passive system.

If this system was fully active and, lets say, the moving parts were some form of linear bearing I can imagine it could be made to work.

Pity the poor programmer....but if the dampers were position (where they are relative to the rotation of the wheel) it should be possible to let the system let the car body move to control the vehicle response. I suppose it would need massive processing power, but really that would only be an issue that needs solving rather than a killer for the idea.

[manchild]

Does anyone know how much F1 pneumatics and wheels weight (separate data if possible)?