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8/6/2019 DAQ Article

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Data Acquisition Systems for Track Day Use

Jefferson Raley

What can it do for me?

A DAQ isn’t the first tool you should buy, it is probably the third. First get a lap timer to drive consistency

and give immediate feedback. Then get a camera and study your sessions. Make sure that you’re using

really working the car through turns and hitting your turn-in, apex and track-out points within inches

every time. It takes most people 30-40 weekends to reach that point. Once you’re there a Data

Acquisition System ( DAQ) can be a big help to find those last fractions of a second. I find it very useful

for:

Testing the effect of different lines, such as

? Is it faster to go through Ricochet at full throttle, versus a confidence lift to settle the car? (no)? Is it faster to track out over the old track at TWS turns 3 and 9? (yes)

? Is the tight line through Horseshoe at MSR Clockwise really faster? (yes)

Identifying and testing the effect of techniques such as

? Trail braking – I bet you’re using it more than you think

? Where is threshold braking worthwhile?

? Can I go faster in certain turns with a little left foot brake?

Identifying general areas to work on

? Look for variance. In my case, apex and exit are always the same, but corner entry varies. That is

what I need to work on.

? Identify low cornering values, sometimes that means you can go faster. Sometimes it means the

road has bad camber or low grip. This is most useful when you’re driving a new track.

Making cool videos

? Many DAQs have the ability to overlay a data dashboard on the video. For those that don’t, you

can buy third party software at www.trackvision.net that allows you to do it

? You can see my sample videos by searching for “SORX7” on Google Video

What won’t it do for me?

The DAQ can’t tell you how fast a corner could be taken, or how late you can brake. It can only show you

how your performance compares to other data. If you never go through a sector in under 10 seconds,

there is no way for the DAQ to know that you could. Similarly, the DAQ can tell you that you’re

generating 1.2g of cornering force at the apex of a particular corner. But the DAQ doesn’t know whether

1.3g is possible.



I also don’t find DAQs very useful for setting up my own car. Sure, it can tell me if the car is oversteering

or understeering. But I already know that because I was the one driving the car. However, it can tell you

if a change made the car faster through certain sectors. Some changes, especially firmer suspensions,

can feel faster to the driver when they are actually slower.

Which one should I buy?There are a few main types of DAQs.

? Legacy systems such as Stack, Race Logic, MoTec and Pi Research. These are used in professional

race cars and tend not to have any built-in sensors. Most of these can be used to drive LCD dash

displays. These are not ideal for a track day enthusiast.

? Real-time video overlay systems such as AIM’s DaVid, Stack’s Overlay Video Logger and the

Multiview 8000 XG. These systems cost thousands of dollars once you add on cameras,

recording devices and sensors. They are also not as good for analyzing data.

? GPS-Based DAQs such as the Race Techology DL-1, RacePak G2X and Traqmate. These have

integrated GPS receivers and accelerometers. They can easily be moved from car to car and aredesigned for analyzing performance in the paddock. As mentioned above, all can be used with

Trackvision to overlay data onto video. This article focuses on these DAQs.

Race Technology DL1

This is a very popular unit, and the one that I chose for my own track car. It records data to a Compact

Flash card for later analysis on your PC. As with all DAQs in this category, it contains dual accelerometers

to measure cornering, braking and accelerating forces. It also contains a GPS receiver for computing

speed and drawing track maps. The DL1 costs about $1150.

Inputs:

The unit accepts the following inputs:

? Three 12v analog inputs (brake on/off, etc)

? Four 5v analog inputs (TPS, oil temp, water temp, oil pressure, steering angle, etc)? Four frequency inputs (for ABS wheel speed sensors)

? RPM signal from your coil or ECU

You can capture data from your car’s existing sensors, or Race technology sells a wide array of sensors.

The most useful of these is a string pot for capturing steering inputs. I’ve connected most of these in my

car, and never use them. The built-in GPS and accelerometers are sufficient for most analysis.



Software:

Software is the most important differentiator in DAQs. All of the units in this comparison have similar

features and capabilities. What matters most is how easily you can turn all of that data into useable

knowledge. Race Technology’s software analysis far ahead of the other products. Some of the useful

features are:

? Playback – this is like the “dot race” as baseball games. You can show multiple laps racing

around the track with G-force vector displays. This is extremely useful for seeing where you are

gaining and losing time on one lap versus another.

? Tabbed Layout – You can customize the screen layout, and save up to 10 different layouts for

the analysis you typically perform. I have layouts for playback, sector charts, sector values and

friction circle.

? Lap and sector comparison – By default the software shows everything in terms of laps and

sectors. This makes it easy to compare the 5 fastest times through a sector, and determine what

you did different each time.

? GG Circle – This is the standard friction circle that everyone has talked about since MarkDonohue showed us how to think about driving. It is very useful for diagnosing your use of trail

braking, among other things.



Seriously, this is the reason I bought a DL1. I downloaded and tested the competitive software in

preparation for this article, and couldn’t believe how bad they are. That said, don’t expect the

intuitiveness or quality of a multi-billion dollar Microsoft product. This isn’t MS Office, and you will find

bugs and annoyances. You can download and test Race Technology’s analysis software at

http://www.race-technology.com/software_10_1095.html

Display

The biggest drawback of the DL1 is that it does not come with a dash display, so it can’t show you lap

times while you’re driving. This means you have to use a separate lap timer, or pay another $675 for

their Dash1 display.

Racepak G2X

This is a very complete system, and includes a very nice dash display at the lowest price in this

comparison. It records data to a Compact Flash card for later analysis on your PC. As with all DAQs in this

category, it contains dual accelerometers to measure cornering, braking and accelerating forces. It also

contains a GPS receiver for computing speed and drawing track maps. The G2X costs about $950.

Inputs:

One nice feature is that, for an additional $350, you can buy a module to connect the G2X directly to

several popular types of fuel injection computers, including Accel, Autronic, FAST and AEM. A majordrawback is that you have to buy one of their $119 Vnet modules for each sensor you add, or buy the

sensors from them.

Software:

The G2X uses a software program called DataLink. Some notable points are:

? Track mapping – As with all of these tools, the software use GPS information to draw an

accurate track map.

? GG Plot – The software has a standard selection for showing the friction circle, which makes it

easier to show this data than on the DL1, which requires some configuration.

? Interface – This is painfully cumbersome. While none of these tools are each to use, I simply

don’t see how you could get valuable knowledge out of this software. Really, I tried to think of

something nice to say. I failed.



The analysis software is critically important to getting the most from your investment. I highly

recommend downloading and testing it for yourself, rather than simply relying on this article. You candownload it for free at http://www.g2xtreme.com/downloads.htm.

Display

As mentioned above, the G2X comes with the best display of any compared in this article. The dash can

be configured to show RPM, speed, lap time, lap counter, lap time difference, lateral G, longitudinal G or

values from external sensors. It also contains programmable shift lights. If you are looking for an

inexpensive dash display, the G2X is the best product. However, if you want to analyze your data in the

paddock, the G2X may not be optimal.



Traqmate Complete

As with the Racepak G2X, the Traqmate comes with a dash mounted display. This is very useful while

you are on track, and eliminates the need for a separate lap time system. Unlike the other 2 systems,

Traqmate stores data internally. A USB cable is used to transfer the data from the display to your PC for

analysis. The Traqmate costs about $1000.

Inputs:

For an addition $129, you can buy the TraqData adaptor. This unit accepts the following inputs:

? Four 12v analog inputs (TPS, water temp, oil pressure, steering angle, etc)

? 2 Digital inputs (brake on/off, etc)

? RPM signal from your coil or ECU

These should provide enough inputs for all but the most extreme data loggers.

Software:The Traqmate uses a software program called TraqView. Some notable points are:

? Playback – As with the DL1, the software can show a “dot race” of your day. This is the default

mode for TraqView, and a very useful tool.

? GG Plot – The software automatically shows friction circles for each driver.

? Interface – This is the easiest software to use, and very professionally designed. However, it has

significantly less functionality that the DL1 analysis package.



Unfortunately Traqmate no longer makes the software available for download and testing. However,

you can download the manual and access screenshots through their website.

Display

The Traqmate comes with an attractive and simple LCD display that can show lap time, compass, speed

(from GPS) or a clock (also from the GPD signal.) The display unit also provides memory for the system.

To download your data, simply plug the display into your PC.

Overall Recommendations

A DAQ can be a very useful tool for improving lap times. In the first year, I was able to reduce lap times

by a second every time I visited a track. However, the DAQ is most useful once you are trying to wring

the last fractions of a second from your lap times.

This article compared three different DAQs that are targeted for serious amateurs. The tools each have

different strengths and weaknesses. If in-depth data analysis is your goal, then the Race Technology DL1

will tend to be the best choice. If in-car timing and simplicity are more important, then the Traqmate is

an excellent tool. Finally, while the Racepak G2X has an excellent dash, the analysis software is simply

not strong enough to make it a serious DAQ solution.



Feature Comparison Chart

MakeRace

Technology RacePak Traqmate

Model DL1 G2X Complete

Price $1150 $943 $1,000

Hardware

Display $675 Included IncludedSensor Ports 12 Unknown 7Cost to addsensors None

$119 persensor $129

Media Compact Flash Compact Flash Internal

GPS Yes Yes Yes

Accelerometers Two Two Two

Software

Playback Yes NA Yes

Tabbed Layout Yes NA N

Compare Laps Yes NA N

Friction Cicle Yes NA Yes

Usefullness Very High Low Moderate

Ease of Use Moderate Difficult Easy

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