Moto-X data logger

[umka]

Just thinking of building a data logger for my motorcross bike (need a 4th year engineering project) but not sure what data I would want so am asking for opinions please.

Here are the things I am thinking of:

Lap time, with/without splits (can compare laps and spilt times between sessions)
RPM (optimise gearing)
Gear position (allows one to optimise gearing)
Throttle position (able to see how quickly one gets on the throttle after corners)
Acceleration/de-acceleration (optimise cornering)
Time in air (allows one to try minimize time in air)
Fork/shock travel (optimise suspension setup)

It will have a digital display and all data stored on an sd card. The display will only really be for checking data afterwards like average lap time and may display real time engine temp and rpm but I don’t think it is practical to put too much as one cant really look at is while riding or do you guys think it should have current lap times and stuff like that. It could have a shift light but again doesn’t seem practical to me.

Any input or suggestions would be much appreciated

[dammad1]

brake and clutch inputs?

[scott411]

the brake and clutch one is a good one, alot of mx guys drag their rear brakes, would be good to point it out,
tps is good idea
gear position indicator and gear change points (in regards to RPM),

[cowpoos]

better still...build a traction control system that works off a ignition cut...it would allow some wheel spin...maybe user dialed in???

[Bert]

Just thinking of building a data logger for my motorcross bike (need a 4th year engineering project) but not sure what data I would want so am asking for opinions please.

Here are the things I am thinking of:

Lap time, with/without splits (can compare laps and spilt times between sessions)
RPM (optimise gearing)
Gear position (allows one to optimise gearing)
Throttle position (able to see how quickly one gets on the throttle after corners)
Acceleration/de-acceleration (optimise cornering)
Time in air (allows one to try minimize time in air)
Fork/shock travel (optimise suspension setup)

It will have a digital display and all data stored on an sd card. The display will only really be for checking data afterwards like average lap time and may display real time engine temp and rpm but I don’t think it is practical to put too much as one cant really look at is while riding or do you guys think it should have current lap times and stuff like that. It could have a shift light but again doesn’t seem practical to me.

Any input or suggestions would be much appreciated

Cool idea, we've been playing around with similier concepts for our road race bikes for the last two years, (using a campbell datalogger). some of your concepts will be hard to measure, like gears and air time. but diff do-able.

if your are focus is on two strokes, air temp and humidity at the airbox would be usefull (and are very cheep), this enables jet matching to air temps / RPM etc. this being one the biggest downfalls with two strokes proformance. not so important with 4's.

another good one is wheel spin vs speed.

Good luck with your 4th year

Bert

[cheese]

Traction control is pretty simple (RMP controlled ones). I think that you need to make sure that the unit is water proof and back light is a nice to have too. If you really wanted to get flash you could add some wireless communications so that a pit crew could monitor the bike real time. I'd suggest using something like zigbee. You could even make it so that the unit is removable so the really weight conscience could have it all wired up and for a race they just pop it off.

[umka]

Ok these are good.

The gear sensor worries me because the mx bikes don’t have built in sensors so it would have to be external so doable but reliability would be a worry.

The air I was thinking of using two-axis accelerometer (g-meter) one for accelerations and other for airtime maybe in conjunction with the suspension sensor.

Air temp and humidity would be good and easy.

The traction control is a worry. I suppose you could measure front wheel speed and compared to rear and if >> than cut every second or so ignition pulse.

[k14]

What about exhaust gas temp and or cylinder pressure? They are both handy to know for jetting (seeing you are running a two stroke).

[NordieBoy]

Oil and water temp.
Air/fuel ratio.

[mbazza]

Any chance of building it to transmit data as you ride? Like the one in the pic below which is a timer transmitted to an on site reciever during motocross? Good luck with the project. Cheers.

[scott411]

not to sure if traction control is wanted, alot of the time you use wheel spin, it would not want to be to harsh when it kicked in
but exhaust temp is a good one,

[paturoa]

What about front / rear comparision of fork & shock / suspension deflection and temp.

I have no idea if they even should be similar but suspect that they should be. By factoring a delay for the speed you should be able produce a graph of the 2 overlayed to see what the difference is for compression and rebound.

This would also be challenging for you to get a fast enough sample rate and enough data collected to be able to effectively compare the damping rates.

It would also be interesting to do some transforms for different soil types off repeatable jumps etc.

edit: hmmm if you did some fft you could drive some led arrays that would indicate to the rider where the major differences are and the rider could remote the adjusters (similar to brake bias adjusters)

[sAsLEX]

Traction control is pretty simple (RMP controlled ones). I think that you need to make sure that the unit is water proof and back light is a nice to have too. If you really wanted to get flash you could add some wireless communications so that a pit crew could monitor the bike real time. I'd suggest using something like zigbee. You could even make it so that the unit is removable so the really weight conscience could have it all wired up and for a race they just pop it off.

Zigbee wouldn't have the range to allow constant coverage, could do a data dump once a lap.

[cowpoos]

not to sure if traction control is wanted, alot of the time you use wheel spin, it would not want to be to harsh when it kicked in
but exhaust temp is a good one,

yeah...thats what I ment about user being able to dial it in?

[umka]

ok so far good infomation would be

data loger:
RPM
Acceleration
lap/split time
throttle position %
brake %
clutch%
gear position

display real time(not data logged):
water temp
last lap time
average lap time
number of laps

i dont think it needs wireless comunication coz whats the differance if the pits can get the data real time or after the sesion. one can not change much while riding so with the sd card one can pull it out and put it straight into a pc and read it within seconds of being of the bike.

could possibly build in a programmable ignition curve (maybe multi map) and rev limiter.

any other thoughts on the data to log or display?