Telemetry

I am looking a picking up a data logger for myself for autocross use. The advice I have received from others generally boils down to: “check out the post processing software for these devices before you buy” so I went ahead and installed a couple of these programs on my computer to test drive them.

The three I have been contemplating are:

Gtech RR - $299 http://www.gtechpro.com/rr.html

This box seems to be oriented towards the drag racer. Yes, I am talking about the RR (road racer) version. The PASS software that comes with this box is the most polished and easiest to use of the three, but it has the fewest features (for the auto crosser). While in the “Road Racer” mode: The plots seem to be limited to lateral Gs Longitudinal Gs and engine rpm, which it claims it can read through the cig lighter. It doesn’t seem to allow the plotting of speed vs time. The device itself may be the limiting factor here, Since it is based on accelerometers and doesn’t incorporate GPS I am suspicious that for an autocross or a road race, the error in speed would build up to unacceptable levels rather quickly. Thus they don’t incorporate it into the results for road race mode.

The Performance Box - $462 http://www.performancebox.co.uk/overview.html

I had the opportunity to borrow one of these from a friend at my local club. The software was slightly less polished than the Gtech software, but it was far more capable. I could generate plots of lateral Gs, longitudinal Gs, speed, and other stuff vs distance or time. I found the interface with the software to be ok, but it seemed as if it was easy to get it to accidentally do stuff you didn’t intend it to do, this would probably disappear with familiarity but it is annoying.

The MQGPS-Quantum 20hz - $499 http://maxqdata.com/Quantum.htm

This seems to be the most capable of the bunch. It’s also the most expensive. The autoalign feature (which helped to align the start of the runs) was nice and handy. The “chart” software seemed to have all of the charting ability of the performance box software. The fact that it animates the runs was also pretty darned cool. If I read the marketing fluff correctly I can also sink external video up with the run data after the fact. Though I did notice the marketing for the “VeQtr” system seemed to bleed over into this area (I think that system is designed to capture and sync the video in real-time)

The only real criticism I can level at the software is that it has the “look and feel” of a windows 3.1 application. Not all of the functions and menu options were labeled as clearly as I would like (it makes learning the software harder than is should). It also didn’t have any help features that would pop up if you hovered over a particular function with the cursor. Considering the cost the crudity of the software is a bit disappointing. I also didn’t get a chance to check out the “flight” software which is supposed to run on a smart phone of palmtop computer.

so finally my questions... sorry for the long post

Are there any other data acquisition devises out there that I should consider? I don’t really want to pay more that $500 for a device. What do the folks at GRM use when testing their projects? Does anyone have any experience with the above devices?

We usually use a Traqmate.

I have a MaxQData complete with pocket PC. Both myself and the previous owner decided that it's a great autocross device, but a little too "fiddly" for track day stuff (I couldn't program segment times while driving, maybe others can). He went to a Traqmate, I'll probably head the same way. PM me if you're interested in the Max.

I'm interested in the Max.

E-

Oh, and this thread should be called data aquisition, not telemetry- since you are not actually going to broadcast live the car data to a stationary computer.

For me, I'm planning on two things- one to make the driver better- basic g's + GPS tracking info, and two- to record engine information so I can make it run better. I may even use some arm position stuff to make the car handle better, but job 1) make driver better, 2) make engine run better.

I've also checked into Race Technology system, too. http://www.race-technology.com/home_8.html

Eric

I have MaxQ high def (10hz) it has been good for autocross, you can easially call up and review data.

the other plus is that you can just turn it on and it will log the data to review later without having to fool with it between runs if you dont want to.

biggest problems involve the PDA, mine freezes on occasion

wow, The traqmate is expen$ive. Its probably out of my price range.

Yes Alphadriver your right... It should be data aquisition... dammit...

Apexcarver what kind of pda to you use?

Wait for Iphone software 3.0

I can just see it. The day after I buy some fancy expensive Data aquisition system apple will roll out some shiny new app for $10...

Some of the apps I have seen already come perioulsly close to what I need.

The dynolicious guys already have LogBox: http://www.bunsentech.com/projects/dynolicious-log-box/

Capt Slow wrote: Apexcarver what kind of pda to you use?

HP IPAQ

Interesting, Tim. Has anybody actually used this Log Box, yet? I may give it a shot for the price. My only question would be what I could use for analysis tools (that can import the CSV data). Looks like I'd be getting the same inputs as one gets from a MaxQData, so with a good analyzer, you could save hundreds.

I don't know anything about logbox but it looks interesting. Any spreadsheet can open csv files

I spent the weekend playing with this FREE! datalogger

I'm using a $6 ebay bluetooth USB hookup on the laptop, a $40 GPS puck (ebay again) and a Nintendo Wii remote as the accelerometer. It can also log OBD2 data and will output the data in a format that can be used in TrackVision

It's a little clunky compared with the commercial offerings, but for the price - it's great!

Tim Baxter wrote: I don't know anything about logbox but it looks interesting. Any spreadsheet can open csv files

You can also convert GPS data between formats with this: http://www.gpsbabel.org/

fifty, that looks really cool, and at the price, is definitley grassroots. Well done.

I've got another vote for TraqMate. I do like the idea of the "free" data-logger, but when I'm scrambling to get the last pieces of my "track kit" together before I leave, get checked in, go through the driver's meeting and make it onto grid in time, I'd prefer not to have a half dozen additional things to think about before the green flag drops...

At $699 for TraqMate basic, it's probably the most feature rich and cost affordable gps based data acquisition system I can find.

WoW the log box is pretty amazing... I have thus far avoided assimilation by the iphone collective. Does this mean resistance is futile?

fifty, nice find. I had long toyed with the idea of a DIY daq system but integrating it seemed a bit daunting. (I was thinking of using an old copy of labview I have left over from college) hmm more food for thought...

Capt Slow wrote: fifty, nice find. I had long toyed with the idea of a DIY daq system but integrating it seemed a bit daunting

MaxQData has a DIY option also: http://www.maxqdata.com/DIY.htm

fifty, I also have to say that system is pretty cool. Pretty much exactly what I'm looking for, too.

It will be interesting to find some software that integrates the GPS and the accelerometer data really well. Some of the high end software does it pretty well, but it's not easy.

For an oldy, but goodie- I've got an old MELD system that we used to tune our challenge car. It's core problem is with the frequency counter- it counts pulses between X time instead of counting time between pulses- so getting a decent rpm signal is difficult. This is for basic analog logging- which is half my issue right now- just getting the car to run well.

I'll have to monitor the message board over there to see if anyone is trying to "enhance" the obd function by replacing it with a simple bluetooth data logger.

But. Then again. That darned iPhone. (I found a trick heart rate monitor/bike app that is going to become a jogging app- I'm SO close to getting one)

Eric

alfadriver wrote: But. Then again. That darned iPhone.

What's the refresh rate on the iPhone GPS? If it's 1Hz (ie 1 GPS data point per second), that's pretty much useless.

fifty wrote:

alfadriver wrote: But. Then again. That darned iPhone.

What's the refresh rate on the iPhone GPS? If it's 1Hz (ie 1 GPS data point per second), that's pretty much useless.

For the dyno program to work as well as it does (which uses both GPS AND the accelerometers), it's apparent that it's capable of doing the job.

Yea, a 20hz GPS would be better, but if you can make what you have work very accurately, nothing wrong with that. Especially when you consider the accuracy of public GPS systems- 20hz is probably not much better than 5hz.

It's all about how it's used more than anything else.

Eric

It appears that the GPS is 1hz but the accelerometers can be polled at at 100 hz.

Would GPS at 1hz be sufficient to correct the drift that accumulates with the accelerometers? The sample data (for the log box, its on their website) has both GPS and accelerometer data. I will have some "real" data to work with soon enough.

I was talking about this stuff to a friend yesterday. What I didn't realize is that he was headed off to infineon for a track day today. Bastard busted out his iphone and downloaded the app right then and there. He was pretty stoked to suddenly have a data aquisition system for a grand total of $2.99

I am glad I am not in the business of selling the Data Aquisition systems...

I just tried the chronogps thing. It froze up my PDA. not cool. Very not cool.

Eric

hmmm I just got a look at the data my friend collected while at a track day at infineon with the log box...

So far I am a bit dissapointed. I will see if I can secure his permission to post some of the data... but the GPS accuracy column never read better than 46M! The speed column never read more or less than zero. And when I tried to view the data set on google maps only one data point was actually on the track...