I am looking for a way to accurately detect a wheeling on a motorcycle. It means that I am searching a sensor to exactly detect when the front wheel leaves the ground. I have to consider the suspension dynamics so I think measure the pitch with an IMU will be not enough accurate.
Maybe use laser sensors attached to the lower part of the fork (front unsprung masse) could be a solution but I am not able to find an accurate sensor with affordable price.
Do you have other ideas?
my thoughts: i'd suggest a reedswitch to detect the forks on maximum extension PLUS hard acceleration (which you could measure with an accelerometer) occurring together. the reason you need both is that the forks could be on maximum extension dropping in a hole/off a gutter etc... not really a wheelie
my thoughts: i'd suggest a reedswitch to detect the forks on maximum extension PLUS hard acceleration (which you could measure with an accelerometer) occurring together. the reason you need both is that the forks could be on maximum extension dropping in a hole/off a gutter etc... not really a wheelie
Interesting but I din't understand how I will be able to see the difference between a hole and a wheeling with the accelero? Where did you think that it should be installed?
What about an IMU fixed on the lower part of the fork? A wheeling stays a rotational motion centered on the contact point between rear wheel and the ground. So I wonder if I will be able to detect when front wheel will leave the ground by regarding the pitch angle.
how I will be able to see the difference between a hole and a wheeling with the accelero?
well the best way i can describe it is by asking you: how often are your forks at full extension? on a road bike my guess the answer would be hardly ever. that is unless you a doing a wheelie and for that you'd have to be accelerating hard.
Where did you think that it should be installed?
i think you are asking about the accelerometer and the answer is as far from anything ferro-magnetic as possible, so on a bike thats pretty difficult, but maybe a fair attempt would get you a workable result
well the best way i can describe it is by asking you: how often are your forks at full extension? on a road bike my guess the answer would be hardly ever. that is unless you a doing a wheelie and for that you'd have to be accelerating hard.
Very hard to know when suspensions are in full extension position.
Some words about the objective. This little project aims to identify the gravity center position of the whole rider + bike. The identification algorithm is based on the load transfer and the equation admits a solution when front or rear wheel leaves the ground (all the load is on one wheel). I think it is easier to study wheeling.
So it is just for one test and not a permanent solution. To begin I have to choose a flat road without any hole or irregularities.
I'm reminded of several things - not sure if any of them help...
To detect wheelspin, test linear speed at the rear wheel - higher than the front? (allowing for rolling radius)
To test for clutch slip compare rear wheel rotation against engine speed (with drivetrain ratio calculated)
Chains add a suprising amount of lag to it all.
Testing for a wheelie could involve front/rear wheelspeed analysis but the differential is too slight, unless your front brake is dragging and the F wheel slows as soon as it leaves the tarmac?
Wheelie schools use the angle of the frame against the tarmac, adjusting trip switches for the average weight of rider and rear suspension compression - using two switches dragging on the ground at the rear, cutting one HTcoil then both (inline four running 2 coils). Too fierce for your application probably, But you could play with that concept easily enough?
My own tiny attempts at motorsport ( Hoghton Sprint ) taught me how tiny the difference is. Sitting only 5mm too far forward I wasn't able to correct weight distribution enough to avoid losing the rear wheel completely.
I was paranoid about popping the front up to high, and even the wheelie school didn't change that.
If I'd had software to keep the front wheel no more than say six inches off and reduce the power SMOOTHLY any higher than that maybe I'd have been less afraid, helping me pit against quicker riders who were simply better than me? I don't think it would need to be any fancier than that, personally?
Good luck with it all, a lot of fun to be had along the way methinks?
If tyres were much better conductors a capacitive sensor on the front wheel would work, but you'd have to
electrically isolate the wheel from the forks (tricky).
I might be over-complicating your question, but can you tell us what you want to do with the sensor's output?
If you want to do something real-time, eg moderate engine power , then we all need to be contemplating something accurate, complex and potentially analog rather than yes/no?
Whereas if you just wanted to light a bulb up, or you were looking at a line of recorded data after a run and wanted to know at which point in the records the front wheel lifted up, then something more crude and less life-threatening might help you?
