Traction feedback device?

[cowpoos]

by 90% functional, i assume you mean accuracy of +-10%, i think i could achieve this. For race applications +-10% is far too inaccurate, 1% is too inaccurate so i do not think it is feasable to develope a this system to the level required for racing.

as for the finer points you ask about, there are heaps and heaps of these, and i would have to outline the whole system on a public forum (i do want to make some cash form this idea if possible :P) to explain it to you, and those without a good grasp of physics probly wouldnt get it anyway.

1% is to inaccurate for a new rider....10% is fine for a racer...they usually have skills and it would be used as a gauge...aslong as it was reading consistantly...I'll give you an example...to get best use out of tyres your rear should have some slip...ie: 104-110% of traction otherwise heated dry rubber is not cleaned off the tyre, to allow moist, malleable
fresh rubber to be used.

If your device could measure in those parameters...then the rider could fish for different lines...and techs for different settings to allow the rider to make much better use of a tyre over race distance..

[bogan]

Mate IMO you are on very dangerous ground with this as good as the idea may be. Say I have one of your devices and are cornering 9% from the egde, but within the +_10%. I notice your gadget is telling me I can corner harder so I push it that extra 10% and have an off, are you prepared for the legalities that would follow?

"to explain it to you, and those without a good grasp of physics probly wouldnt get it anyway."
Yup we are all a pack of dumb arses here, so you didn't really want our opinions then?

actually, if i find the thing is 10% off, 90% of traction used, gets scaled to 100% of traction used, problem solved.

and what i meant was i want you opinion on the application of the idea, rather than the implementation.

@Usarka, i make the assumtion that a rider will start off not too hamfisted, and get more and more hamfisted as they push the limits, this system will apply that to the traction used, a ham fisted exit may use 90% of the traction, so next time (int theory) they will know not to ham it up even further

[cowpoos]

as for the finer points you ask about, there are heaps and heaps of these, and i would have to outline the whole system on a public forum (i do want to make some cash form this idea if possible :P) to explain it to you, and those without a good grasp of physics probly wouldnt get it anyway.

I believe...that if you don't explain the finer point...we can't give you rebuttal or positive feedback...


And I still think...you a seriously underestimating the amount of forces involved..I know your a physics student...but the amount of different forces involved in a motorcycle are huge...they are a very dynamic critter [machine]....especially the suspension!

BTW...is it sensing on both wheels??

[CookMySock]

Cornering is a balance between gravity and lateral forces so any forces measured would still be acting down through the centerline of the bike and it would be difficult to seperate the differing forces into their component vectors

Agreed. In fact, like an aircraft in a balanced turn, the only force remaining should be vertical with respect to the motorcycle, the z accelerometer plane, which should increase steadily as the angle of lean increases and the suspension compresses. The x accelerometer plane should show a tilt in, and then return to zero, and accelerometer y plane should show any power or braking applied.

Perhaps the x curve as the rider tilts in, could be examined afterwards to see how smooth it was, or maybe the device itself might sneer at the rider on occasion just to smoothen things out just a little more - a bit like a coach just asking a little more smoothness every now and then. Maybe all the curves could be examined in this fashion, and a "rider trainer" mode could be implemented.

The final product would (most likely) consist of a speed sensor on each wheel (like abs systems) a main electronics box to be rigidely mounted to the frame, and the indicator bargraph to be stuck anywhere in view.

If you did this, you could take the differential of each wheels' speed, and develop a basic traction auditing system. You would see quite a sharp spike in the differential if either wheel took a microscopic loss of traction. In fact, the smaller the slide, the larger the differential spike.

Even further, if you too the difference of the front differential and the rear differential and wound the gain up a bit, you might end up with some interesting data - probably a squiggly little erratic line, but if the rider had a little "oops" it would be very revealing to check the graph later on, as that squiggly little line may just have a nasty big snatch in it, indicating that said "oops" was a little to close for comfort. This could perhaps be used to light an idiot light on the panel (to remain lit for some hours) to warn said idiot that both wheels WHERE IN FACT doing completely different things just *then*. You might call this idiot light a "DONT DO THAT AGAIN, SON" light.

The device measures the cornering lean angle, as well as the g-force generated from going into a dip or over a crest, and also the bikes angle (uphil or downhill). The poll relates to the ideal realisation of the device, which would give a reliable measure of traction used, with the only exceptions being road surface and camber, which the rider is expected to see and adjust speed accordingly

If you have a front and rear accelerometer, you might be able to predict under what circumstances the bike will misbehave badly, such as entering a bad tank slapper, and again illuminate said idiot light should they have just got thiiiiiiiiis close to provoking one. "DONT DO THAT AGAIN, SON"

Yeah it could be a fun gadget, and I think it would increase safety. Sure, many racers have all this crap programmed into their brain, and they live on the bleeding edge of the slightest nuance of it, but we mere motals could do with a light on the dash.

disclaimer: don't rely on my maths.

Steve

[bogan]

1% is to inaccurate for a new rider....

how many new riders do you know that ride to within 1% of the limit?

For the racing applications, probably parts could be used but i think a differernt design (though using same principals) would be far better for them

[cowpoos]

how many new riders do you know that ride to within 1% of the limit?

For the racing applications, probably parts could be used but i think a differernt design (though using same principals) would be far better for them

In all honesty...I can see its use in racing....I don't see it for newbies.

I have seen newbies fall off at speeds so slow...physics wouldn;t be able to under stand it...They should stick with looking ahead and learning to feel the bike below them...not something telling them how much throttle to dial on..thats something that should be learnt from feel...not a device!! thats how skills are created!

[bogan]

I believe...that if you don't explain the finer point...we can't give you rebuttal or positive feedback...


And I still think...you a seriously underestimating the amount of forces involved..I know your a physics student...but the amount of different forces involved in a motorcycle are huge...they are a very dynamic critter [machine]....especially the suspension!

BTW...is it sensing on both wheels??

im not after a technical rebutal, rather one on the idea of the system, which so far im feeling is positive (after filtering out all the tech misgivings)

i realise the suspension does a lot of work, but its design is to keep the tyres providing an even amount of force to the ground at all times. In real world situations this force is not even of course but oscilates around the even value, but when a higher force is applied to the ground a higher amount of traction is also obtained, meaning the effect is largely (though not completely of course) negated.

[HDTboy]

I think it would be more of a gimmick than useful. Most learner riders aren't going to out-corner the traction limits of their tyres, and should be looking at where they want to go rather than a guage

[bogan]

Agreed. In fact, like an aircraft in a balanced turn, the only force remaining should be vertical with respect to the motorcycle, the z accelerometer plane, which should increase steadily as the angle of lean increases and the suspension compresses. The x accelerometer plane should show a tilt in, and then return to zero, and accelerometer y plane should show any power or braking applied.
...
disclaimer: don't rely on my maths.

Steve

thanks steve, yeh your reasoning there is sound, though it is possible to very accurately measure the cornering g-force of a leaned vehichle, that was the first problem i overcome for this project, the prototype for this part has been tested and results are good

[cowpoos]

Agreed. In fact, like an aircraft in a balanced turn, the only force remaining should be vertical with respect to the motorcycle, the z accelerometer plane, which should increase steadily as the angle of lean increases and the suspension compresses. The x accelerometer plane should show a tilt in, and then return to zero, and accelerometer y plane should show any power or braking applied

you will be missing a whole bunch of forces that a bike produces!!

[bogan]

I think it would be more of a gimmick than useful. Most learner riders aren't going to out-corner the traction limits of their tyres, and should be looking at where they want to go rather than a guage

Yeh i realise this, but sometimes it would be nice to know how much more force can be applied, my first off was an oil slick evasion at a yellow light, locked the front up before the slick as i didnt know how quickly i could actually stop, i think if id had one if these i would not have had a lock up

[CookMySock]

I have seen newbies fall off at speeds so slow...physics wouldn;t be able to under stand it...

You underestimate what modern digital signal processing can sense.

They [newbies] should stick with looking ahead and learning to feel the bike below them...not something telling them how much throttle to dial on..thats something that should be learnt from feel...not a device!! thats how skills are created!

But that is the hard part for newbies. Racers have that forever stamped on their brain, but newbies are completely feeling in the dark - they have no feel for, and no concept whatsoever of how far they can push it, and whether that little headshake or front-end slide they just had was safely ignorable, or whether it nearly took their life, or whether that little almost-jump they took nearly irretrievably tucked their suspension or not. A box that frowned and glared at them would be just the business.


Steve

[cowpoos]

i realise the suspension does a lot of work, but its design is to keep the tyres providing an even amount of force to the ground at all times. In real world situations this force is not even of course but oscilates around the even value, but when a higher force is applied to the ground a higher amount of traction is also obtained, meaning the effect is largely (though not completely of course) negated.

No...thats not just what suspension does...and add to that chassis geometry.
I does alot lot more...there are 500 page books avalible which will outline a fair bit of the info...but not all.

[cowpoos]

You underestimate what modern digital signal processing can sense.

You are probally right

But that is the hard part for newbies. Racers have that forever stamped on their brain, but newbies are completely feeling in the dark - they have no feel for, and no concept whatsoever of how far they can push it, and whether that little headshake or front-end slide they just had was safely ignorable, or whether it nearly took their life, or whether that little almost-jump they took nearly irretrievably tucked their suspension or not. A box that frowned and glared at them would be just the business.


Steve

I would like to reply to this properly...but it would take levels of motivation I don't have right now...I might tomorrow.

But generally...its around fear...and instinct. and how you use it...and it can be taught...with out huge amounts of drama and hassle!

[HDTboy]

hmm, i had not considered people misusing it. my thingy is not sposed to tell people if theres oil on the road, they have eyes for that!

my first off was an oil slick evasion at a yellow light, locked the front up before the slick as i didnt know how quickly i could actually stop,

By your own admission the system is useless.
ABS is already a factory option, and prevents tucking the front.

Not trying to rain on your parade, but I don't see the benefit