Traction feedback device?

**bogan** · 25th April 2009, 18:03

Ive been toying with the idea of an electronic training device to help riders learn the limits by displaying the amount of traction being used in any given situation.

What it does is takes sensor data from the bike and works out all the net forces acting on the bike, it also calculates the weight distribution on each wheel. Using the cornering g-force, acceleration/decelleration forces, weight distributions, crest/dip forces, etc, it calculates the percentage of traction currently being used for each wheel and displays the highest one.

The value it uses for this maximum amount of traction is calculated using a number of constants which are programmed into the system, these are programed for each bike it is on. They include weight, rider and bike, tyre profile and friction co-efficient (can be found with two sets of scales).

What it cant do is sense the road conditions, potholes gravel, oil, wet, camber, the rider is responsible to back off if the road is slippery.

The display is currently under review, an LED bargraph is used in the current prototype, which shows the percentage scale in realtime, and records the max percentage used round a corner which it then displays after the corner for rider review. Other suggestions have been to use a beeper, beeps faster the more traction you use, and also to do datalogging in conjunction with GPS data.

The working idea of it is that it provides riders with a measure of the upper limit of traction they have available, (kind of like an intense track day would do, only without the practical experience obviously). For example, if a rider did a quick stop in 70m thinking he was using most of the traction, then put this gismo on the bike and found he could use a lot more, when he next did an emergency stop he could stop in 55m, thus being safer. There would be similar benifits while cornering and accelerating. The bit where this doesnt work is when the road conditions are poor, if he tried getting close to the gizmos idea of traction he would lock up, so the rider is still responsible for noticing porr road conditions and adjusting speeds and stopping force.

There is also the possiblity of a brak test to find the available traction, this would mean the rider rides along and locks up the rear wheel, the gizmo would then examine the deceleration needed and work out the force required to lock it up, and thus calculate the current road friction co-efficient, but again this would still not solve the problem of potholes, gravel spots, and oil slicks, though it would take care of different road quality and wet roads.

Your thoughts on this idea?

**kiwifruit** · 25th April 2009, 18:10

Originally Posted by bogan

Ive been toying with the idea of an electronic training device to help riders learn the limits by displaying the amount of traction being used in any given situation.

Display is (currently) a bargraph and a warning light which fills up as you go faster and faster (and use more and more traction) while cornering.

So far ive got a computer simulation, and a prototype with a limited number of sensors.

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.

Your thoughts on this idea?

Sounds interesting but i can see a few problems, using it as a training device or a guide for riders.... especially new riders. One wouldn't want to be relying on a graph or a set of lights to determine how far one is from "the limit". There are so many variables outide the few inputs you speak of using. Speed and traction are not necessarily inversely proportional.

In saying that, it sounds like a cool idea, copyright it!

**bogan** · 25th April 2009, 18:26

opps, i forgot to mention, it 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 only major thing it doesnt measure is the road camber

**AllanB** · 25th April 2009, 18:48

Sounds like a fun toy. I don't want to bag it but it cannot take into account the most important variables such as road surface (damp spot, cow shit, gravel mid corner etc). Or tyre temp or tyre wear.

Lets face it if you are on a big lean you know about it!

Also the last thing I want to be looking at cranked over mid corner is a pretty graphic display. As an example some years ago on a former bike, I mounted one of those little vehicle angle spheres from a 4WD to the top of my instrument cluster.

It was cool.

So cool that one tended to chance a quick look at it mid corner.......suffice to say it did not stay mounted on the bike for long.

Now a Heads up display on my visor...........

Edit - as a instrument you can study after a ride it may be cool - download onto your computer and check out the lean angles.

**kiwifruit** · 25th April 2009, 18:51

Originally Posted by AllanB

Sounds like a fun toy. I don't want to bag it but it cannot take into account the most important variables such as road surface (damp spot, cow shit, gravel mid corner etc). Or tyre temp or tyre wear.

Lets face it if you are on a big lean you know about it!

Also the last thing I want to be looking at cranked over mid corner is a pretty graphic display. As an example some years ago on a former bike, I mounted one of those little vehicle angle spheres from a 4WD to the top of my instrument cluster.

It was cool.

So cool that one tended to chance a quick look at it mid corner.......suffice to say it did not stay mounted on the bike for long.

Now a Heads up display on my visor...........

Edit - as a instrument you can study after a ride it may be cool - download onto your computer and check out the lean angles.

yeah, wot he says

**cowpoos** · 25th April 2009, 19:04

Originally Posted by bogan

Ive been toying with the idea of an electronicing training device to help riders learn the limits by displaying the amount of traction being used in any given situation.

Display is (currently) a bargraph and a warning light which fills up as you go faster and faster (and use more and more traction) while cornering.

So far ive got a computer simulation, and a prototype with a limited number of sensors.

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.

Your thoughts on this idea?

EDIT :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 only major thing it doesnt measure is the road camber

It won't work...there is to much data missing.

**bogan** · 25th April 2009, 19:15

yeh i have thort of the whole looking at road during cornering, so it records the max traction usage and displays it for the next 5 secs after the corner.

As for the 4wd things, they measure the direction of net acceleration so would not be suitable for measureing lean angles anyway.

I realise it would be far more effective if it could see road hazards like gravel etc, but it is unrealisitc to try and sense these. The rider is responsible to realise if its wet, he should only use half the available traction

The idea behind it is the rider is able to learn the limit of traction on normal corners, so will have a better understanding of the bikes limits during emergency situations, such as avoiding hazards like oil slicks or gravel spots.

@Cowpoos, would you mind elaborating on the data it is missing?

**CookMySock** · 25th April 2009, 19:20

You could build a device, so that it watched how you were cornering, and if you gave it a fright it could stand the bike up for you - thereby saving you the bother. That would be easy to build, and you could have it err on the side of "safety" (sic).

Steve

**AllanB** · 25th April 2009, 19:30

Originally Posted by DangerousBastard

You could build a device, so that it watched how you were cornering, and if you gave it a fright it could stand the bike up for you - thereby saving you the bother. That would be easy to build, and you could have it err on the side of "safety" (sic).
Steve

Thats a piss take right Steve?

A computer that halfway around a corner decides you are hammering it over to far and stands you up, stands you up into the path of a oncoming 4WD.

Ah I'd say NO to that.

**CookMySock** · 25th April 2009, 19:40

Originally Posted by AllanB

Thats a piss take right Steve?

Damn, I'm busted!

edit: LOL our mate cowshit took my "good idea" literally (abusive red red - again.) Of course, I take this as a compliment - you never can tell if I am serious or not. Haha.

Steve

**BMWST?** · 25th April 2009, 20:01

a device that measures lateral acceleration is al that is required....lean angle is directly proportional to lateral forces.This way would be no more limited than the original..

**bogan** · 25th April 2009, 20:12

Originally Posted by BMWST?

a device that measures lateral acceleration is al that is required....lean angle is directly proportional to lateral forces.This way would be no more limited than the original..

this is correct for crude modeling (and is where the prototype system is currently up to), but it does not take into account speed, rider weight distribution, or incline changes, the final system i propose does.

**CookMySock** · 25th April 2009, 20:15

Three-axis Accelerometers are cheap and simple to use.

http://www.evilmadscientist.com/article.php/ADXL330

Steve

**cowpoos** · 25th April 2009, 20:19

Originally Posted by cowpoos

It won't work...there is to much data missing.

Originally Posted by bogan

@Cowpoos, would you mind elaborating on the data it is missing?

yep...read below

Originally Posted by DangerousBastard

Damn, I'm busted!

edit: LOL our mate cowshit took my "good idea" literally (abusive red red - again.) Of course, I take this as a compliment - you never can tell if I am serious or not. Haha.

Steve

Doubt it...being a dumb arse...you had no thought of consequence's when you opened your mouth [typed...whatever] and then realised how stupid you were a posted this rubbish!! you are a almighty cock...and a rather daft one!!

Originally Posted by BMWST?

a device that measures lateral acceleration is al that is required....lean angle is directly proportional to lateral forces.This way would be no more limited than the original..

What is not prepotional is avalible grip...there are differences between every single type of bike...the amount of available grip available and second mechanical grip created..and then tyre's...every one is different...and not to mention different rolling diameters at different speeds...

Then...there is the human factor...different riders balance different bikes in different ways...you have differing riding styles, which can create more grip that others...timid riders are stiff on a bike...and lessen grip because of...bad throttle control will alter grip massively...

You will have to be one mean physicist,with a lot of technical knowledge a world class suspension tech on speed dial, every manufactures spec's [the true ones no the brochure ones], be in the tyre manufactures back pocket and have incredible physic ability aswell.

I think that if a product could be made to do this...it would be a great 'Tool' but with so much data that is almost imposible to input into your model...you are on a hiding to nothing....

Great concept though

**FLYMO** · 25th April 2009, 20:21

maybe some training wheels that lock in position so when u get home ya can measure the angle u have been on and go wow
then again they would be heavy and chrome for most harleys