Dntlift

Firstly, I have no clue where this belongs, move it if it needs to be moved. I guess at some point this could become a how to.

But since, correct me if I am wrong, but your an electrical engineer, no?

I had/have an idea and I want your thoughts on it.

Basically, I was thinking what if we made a common lap timer?
I know that there are certain lap timers that work with some sort of infared signal, throw the source on a tripod behind the concrete barrier near s/f and have some sort of receiver in car that will trip a clock? Each car using it would run its own clock, no need for individual signals, ect. I know its possible cause Ive seen a system very similar to this in use before, but what would we need on the car side to receive this data, and turn it into laptimes? Is this at all do-able or do I just have my head stuck up my ***?

Edit: something like this actually, http://www.sumomoto.com/bestlap.htm?...FQ5T7Aod12SnLg

Track

We can, but there is plenty of them available and they are cheap I think. Its really just like a remote control, but rather than working on a button press, it just sends a signal very frequently to catch you as you come by. depending on frequency will be your accuracy/precision.

Its pretty doable, but then again, why make a IR based one when you can make an MCU with an Accelerometer and GPS unit for ~$90 and have plenty of outputs and inputs for other random sensors?

Dntlift

Yeah, I didnt realize how cheap they were until I looked at that one...

MCU? Also, accelerometer would be nice, GPS could work. I feel like they are a little less accurate, but Im certainly not at the level where that matters yet. What kind of inputs were you thinking of?

Track

Here is my whole Data acquistion idea:

To start with:
GPS
Accelerometer
Steering Angle
Throttle position
Tire Temps

Add-on:
Suspension displacement
Wheel speeds
Tire PSI
Engine RPMs
Gear


Possibilities:
Brake temps
Oil Temp
Water Temp
Differential/Transmission Temp.
And a series of other indications.

For the purposes of improving as a driver, I think the basics are whats needed:
-GPS will plot out your location on the track
-Accelerometer will tell you Gs, show you the traction circle and where you are not using it fully.
-Throttle position and steering angle will show you smooth-ness, tracking out, and where you could try to add more throttle and remove some steering (ex. turn 1 RA, turn 7, turn 12).
-Tire temps is basic, are you overheating your tires on track? Are you getting them up to optimal temps at the PSI you run?

The rest are all additives to make sure everything is running well. At some point in the future with an OS Giken and some electronics you could make a VERY advanced traction control system if you wanted to (wheel speed, steering angle, throttle position).

Track

Btw, I looked into the IR stuff, not sure how clean it will work (we will need to do quite a bit of testing before taking it to the track), but its not very expensive.

IR Transmitter: 55c each, lets say we do an array of 3-5 to guarantee signal strength and angle, so thats at most $3
IR Receiver: $2 each, we will need 1 each.

Lastly, there will be some minor electronics to use, specifically we need to PWM the transmitters to 40khz/56khz depending on the receiver. and a MCU to act as a timer and read in the receiver pulses.

I would estimate mass-production costs for the two together at no more than $10 (probably more like $6 if you optimize costs as much as possible). for me and you, it will be around $25 each person.

Dntlift

That sounds pretty awesome!

I like everything you have on the first list. I would move suspension up to the first list, but only really to determine other things, such as setup.

As far a possibilities, I dont really need those, cause I can datalog those through the MS. But I can see why you would want them.

If we can get this to work, 15 bucks a person is phenomenal! my only thing is, I still dont know what a MCU is and what it does, like what kind of data would we be seeing? memcard storing the data? Display that pops up times. I know you were talking about having a memorycard being rather simple to do. If it comes down to that, I could try to read a bit more into programming and come up with something to display the data. tis always a possibility.

Track

MCU is a microcontroller. At this point in time, I would output to a SD card, you can write up a quick data point plotter and grapher in python and run it on the file. It will graph the GPS coordinates on the blank slate which will look like the track. You will also be able to see a graph of the data points. Ideally you would be able to scroll through the data points one at time and see your position on track +/- the GPS accuracy.

Its simple and not simple. I personally don't have the time to write up all the code for everything, so its not really a one man job to be done in a reasonable time. But I think that I can work on it in my spare time and see how it does by testing it on track. The data box's biggest difficult is mounting the tire temp sensors and how to locate the steering rack position. On our old car we had an extension past the splines with a notch in it and thats where the sensor went. On these cars, its not possible so some sort of string and spring system will need to be used.

Ultimately, I think integration with a MS system would be great. full functionality of reading things like EGTs, boost, AFRs, throttle, and logging EVERYTHING together would be amazing. And over kill. Tbh, the MCU I am looking at is 72MHz+, which is beefy enough to do 25hz+ on the sensors and run a car engine. If I am not mistaken the original MS was 8 mhz, the MSII is 24mhz, and I think the MS3 is 50mhz. I don't really know, this stuff needs a lot of design, so take the running a car engine with a grain of salt here. With that said, a Beagleboard is $140 and is 600Mhz, with every ------- peripheral you would ever need on it (include HDMI video out for a display and optical audio output for made BASS).

Anyways, I see need to find another programmer to get me motivated. hahaha lazy ----, I just do this all day so there is not a strong appeal to do this in my spare time...bbut I find myself looking at MCUs more frequently and shopping for sensors, so its only a matter of time before I say ---- it and start to dig in.

Dntlift

I agree that logging everything would be overkill, 100%. All I was saying is that logging those things would not necessarily be needed, seeing as my MS could log most of it cause that is half of what it does. (not really but you get the point)

I feel ya on the programming, which is kinda where I want to be a part. Ive taken a very basic visual basic class, so I understand the basics of programming and computer logic. Unfortunately that is about it, but depending on various factors, I would be interested in giving it a shot!

Send me some links to some of these sensors you had in mind for steering input, ect. and ill see if I cant figure out some way to make it work.

tbh the simpler the better imho, while cool as ----, I dont feel like we need to know every ounce of data that can be retrieved from our cars.

Track

We will talk more about this in private then. If you are serious about working on Visual Basic, this makes things much more plausible to me.

Dntlift

Sounds like a plan! Im serious, cause Id like to learn a bit more programming.
But school and a few other things come first, so it wont be quick. well talk