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[morepower]

How are you going to measure torque?

The problem is your system is re-active, not pro-active. The bike is already spinning and sliding before it starts to work. If you cut power once the back has stepped out then it could be highside city

The problem is your system is re-active, not pro-active. The bike is already spinning and sliding before it starts to work. If you cut power once the back has stepped out then it could be highside city

Wheel speed system is also re-active. The same applies. You wouldnt want to cut power, just soften it in proportion to the amount of spin and feed it back in gradually as the bike straightens up.

It's reactive to the wheel spinning but it reduces power to prevent a slide. You system needs the bike to slide.

Sorry if I get this slightly wrong R1Ninja.. I picked your posts in the order they came up ...

But R1Ninja is right with all of these. The system has to be pro-active not re-active. The system has to know what is happening at the time it happens it has to know how to act so as not to cause more problems than it solves. The sensors will work with the ECU and traction control software so that once it starts to wheel spin or slide it can act in a way so it doesn't spin more and have to sort out the problem it has to be working as soon as it happens so you need to know the wheel speed of both wheels as well as suspansion travel so that if the bike wheelies it knows what is happening and doesn't kill power until the wheel speed catches up and then picks up the front wheel again instantly as the front wheel speed catches up as soon as the front wheel hits the ground. The wheels sliding or just spinning up is corrected more gradually so power can be applied more in a smoother action. The system has to know if one or both wheels are on the ground and how to work in either case. It needs multiple sensors and some complex set up to really work. The Ducati system will possibly not work as well as it could by just turning it on but adjust the way it works and it could be brilliant. But that is the problem...Getting it set up as what works for me will probably not be the same for anyone else....

Again sorry R1Ninja if didn't pick up what you meant... But it seems you work with stuff that works at a similar level or greater and know the system has to know what to do in several situations and not just sort it out when it could already be too late.

[jamma10566]

Surely for a system to be pro-active, you'd need to set it up within certain parameters that allow for different levels of grip so that the system would know what amount of power can be applied for a given angle of lean and then never allow the bike to exceed that. If so, then to work effectively, and prevent slides, it would have to be set up for the least grippy corner when the tyres are at their least effective.
Any other way of doing it is surely re-active. The bike needs to react to the various sensor inputs and soften power accordingly. ie, react to a difference in wheel speeds. It cant do anything until it has something to react to. If the wheel speeds are different then a slide has already started and needs to be corrected.

[morepower]

Surely for a system to be pro-active, you'd need to set it up within certain parameters that allow for different levels of grip so that the system would know what amount of power can be applied for a given angle of lean and then never allow the bike to exceed that. If so, then to work effectively, and prevent slides, it would have to be set up for the least grippy corner when the tyres are at their least effective.
Any other way of doing it is surely re-active. The bike needs to react to the various sensor inputs and soften power accordingly. ie, react to a difference in wheel speeds. It cant do anything until it has something to react to. If the wheel speeds are different then a slide has already started and needs to be corrected.

True and this is where the suspension travel sensors come into play as well as wheel speed sensors front and rear even using a gyro helps with more data. The more data they can measure and record the more they can look over it and see how a bike reacts just as the traction control is needed. The software is the really clever part and I would love to spend a week seeing first hand how they make it all work. They can like you say work out how it would react in the worst conditions but for racing it needs to be on the edge of the limits all the time and it really gets complex getting the ECU to work. The sensors are easy but making it work is the problem.

[r1ninja]

That's why motogp now use gps so that the bike knows exactly where it is on the track  and the T.C is adjusted to the individual grip of the corner.

Cars have a massive advantage here as full race distance simulations can be run on the suspension with the car sitting on a jig.

[jamma10566]

That's why motogp now use gps so that the bike knows exactly where it is on the track  and the T.C is adjusted to the individual grip of the corner.


But how does it adjust itself to the tyres going off?

[r1ninja]

Not sure that it does adjust itself to the tyre going off but certainly as the race goes on then the mapping is altered so that the bikes don't run out of fuel, so the power delivery will be less fierce.

[morepower]

Not sure that it does adjust itself to the tyre going off but certainly as the race goes on then the mapping is altered so that the bikes don't run out of fuel, so the power delivery will be less fierce.

The system does allow for wheel spin of up to a pre set percentage over the front wheel, so even when a tyre has gone off it will not spin more than the preset amount. But there will be an even softer setting for later in the race. The pro-active part is knowing from a gear, speed, RPM and throttle position the odds of getting the bike to spin up quicker than the ECU can compensate for... As I said I only know a bit about how it works...If I knew a lot more I could charge a shed load for setting up traction control......

[jamma10566]

So then surely the "pro-active" part of the system is just there to compensate for REALLY ham fisted riders. Racers would know when the odds of a slide are high and temper their throttle hand to suit.
Apart from that, the system is re-active to wheel speed difference, and like you said, the wheel has to spin to give the system something to react to. It cant be set to cut in at a very small difference because wheel speeds will change in relation to each other as soon as the bike is leant over because of the change in rolling radius.
So therefore, with a conventional system, the bike will have to slide a certain amount before the TC will correct it.

[r1ninja]

Nah it can pick up that the wheels have broken traction before the bike slides. The same as top notch ABS never allows the wheels to lock.

[truescot]

as i mentioned before, if there is a strain gauge somewhere around the rear sprocket you could tell instantly that traction is lost as the amount of resistance reduces massively when the wheel starts to spin, combine that with throttle position and revs and you have a traction control system that wont let the wheel spin more than half a turn, not giving it anywhere near enuff time to slide out.

[morepower]

The problem with catching the wheel spin and stopping it all together is that it is not the best way to go fast. Even at close to top speed there is some wheel spin on your bike when you are accelerating.. OK not a lot but there is some. The bike wants some spin anyway as I said between 5 and 10% is normal so you have to allow for that......

[jamma10566]

as i mentioned before, if there is a strain gauge somewhere around the rear sprocket you could tell instantly that traction is lost as the amount of resistance reduces massively when the wheel starts to spin, combine that with throttle position and revs and you have a traction control system that wont let the wheel spin more than half a turn, not giving it anywhere near enuff time to slide out.

When I first read this my thoughts were "nah, wont work" because the strain on the swingarm would be constantly changing as you rolled on and off the throttle and you wouldnt want the tc cutting in just because you rolled off the throttle. But combined with a throttle position input it might just work. Its all very well saying "This is what they use now so anything different wont work" but if we all thought like that, we'd still be riding horses. Strain guage wouldnt necessarily need to be near the rear spindle. A finite element analysis of the swingarm would show up where the highest strain concencentration under compression would be and this would be the best place for the strain guage to be for maximum sensitivity.I like your thinking.

[truescot]

The problem with catching the wheel spin and stopping it all together is that it is not the best way to go fast. Even at close to top speed there is some wheel spin on your bike when you are accelerating.. OK not a lot but there is some. The bike wants some spin anyway as I said between 5 and 10% is normal so you have to allow for that......

i would guess with a strain gauge you could set it to how much of a drop off of resistance it would take to activate, i'm not getting into rear wheel steering here of course but generally the little slip there is would be easily discounted from the system plus its easilly adjusted for a specific riders prefference

plus of course the other things u mentioned like wheel speed etc, the only thing with it is the more sensors you add the more complex it gets to get the right settings for each of them, but i know quite a few games programmers who i am sre could knock up the kind of start off point pretty easily

[r1ninja]

So then surely the "pro-active" part of the system is just there to compensate for REALLY ham fisted riders. Racers would know when the odds of a slide are high and temper their throttle hand to suit.

Yep, precisely why Lorenzo highsided himself a few times last season. TC isn't totally foolproof.  If it was then you'd seriously hamper the power of the bike.

[jamma10566]

Lorenzo is a VERY talented guy. Probably putting too much faith in in his electronics caused his problems. Good argument for banning all rider aids, let the real talent shine through.