Data Acquisition, fact or fiction, requirement for any car, or advanced.

[clarkspeed]

Post #3 – Lots and lots of data on the cheap

Now I am breaking into something new, a device that automatically and electronically records data for you.  Something that takes samples at least 5 times a second of additional parameters you cannot see easily with the human eye.  75 years of electronics development has given us tons of options to look at our race cars in different ways that were only a dream in the 1950’s.  And stuff has gotten so cheap, most everyone uses something more than a tire pressure gauge and pyrometer these days to analyze performance. 

 

First up let’s talk cameras, both still and motion.  Cary has posted on this subject many times in this forum and I think it deserves its own section here.  I am going to consider this really the first step into electronic data analysis.  There is just so much knowledge that can be gained with so little money.  From Cary:

 

“It also important to get pictures from the event where you can see your car loaded up in a corner as well as those that are faster than you or in the same class.  There's a lot that can be learned from these photos.  And ideally have someone take video of the same cars and if possible use a tripod so you can tell what are and are not trying to see if the car is hopping or the camera operator (phone owner) had too many lattes.  These days almost everyone has a camera and most of these also capture video and those get shared on social media, which makes it easy to collect this info.  “

 

I will also add, you don’t need any fancy equipment here.  Obviously phones can do this well,  everyone has one, they process the video immediately, and have big screens to review, but they do tend to be expensive and can be tricky to mount. Go-Pros are nice since they are hi-def, image stabilized, auto correct sound levels, etc.  If making high quality social media posts and movies, these are the best, but for extracting basic info they are kind of overkill and they are also expensive.  There are many Go-Pro clones out there and mini video cameras that are super cheap. Especially on the used market.  And 720p resolution is fine for most analysis. Over the years I have collected a small box full of video cameras that I use in various applications. Many are in the $25-30 range and I don’t care if they get destroyed in action. Some have small display screens so you can review the video immediately.

 

These are some examples of analyzing video:

 

1.     Facing the front you can analyze your racing line and track conditions. By freezing the frames you can look at distances to objects and the sound can indicate shift points and lifting points.

2.     Facing the dash you can record all the gauge readouts.  Minimum speed, maximum speed, RPM, shift points, etc.

3.     Facing the driver you can analyze how the 4 inputs are used.  Gas, brake, steering, and shifting.  Also eye placement.

4.     Under the hood you can look for leaks, smoke, strange sounds, vibrations.

5.     Aimed at suspension you can look at displacement, roll angles, shock travel, binding, vibration. Some distance markings or a ruler in the background for reference helps. I drop these videos into PowerPoint and create reference lines on top of video to scale.

6.     Aimed out back you can get a different perspective on the racing line and understand what happened when other drivers pass or attempted to pass. Also look for smoke!

 

And the list can go on.  Sometimes you can angle a camera to pick up multiple views. Or you can use a software like RaceRender to synchronize multiple videos together. About the only difficult thing is the more cameras you use, the more you need to plan ahead for.

 

1.     Making sure all cameras are fully charged and have memory capacity

2.     Making sure they are aimed in desired location

3.     Turning them all on at the proper time.  For a big race I have my crew person do a walk around before I go to grid.

4.     Turning them all off and extracting memory cards after the run.

5.     Downloading and then finding time to review the data.

 

Once you start collecting electronic data you will find it is easy to collect way more than you need.  Same with cameras.  They are so cheap and easy, I always run at least 1.  For big races I will run 2 or 3.  If only using cameras, it is best to think about what you want to gain from reviewing.  Have a plan before you go out.  Once you start reviewing it is easy to get hypnotized by the fun you were having. 

 

Enough for now.  Data systems next.  Tons of good stuff already posted by you guys so I don't need to write much.

Clark

[jhm]

On the topic of data logging tools, has anyone had any first- or second-hand experience with the Racebox Pro?  (I didn't know this, but it's produced in Bulgaria.)

 

Seems to have a lot of organic features not inherent in many other data devices.  The biggest weak point I've come across is the app apparently, but the company seems to be improving it and releasing new updates regularly.  Overall, looks like a lot of capability for the money ($279 on Amazon).

 

https://www.racebox.pro/

[tube80z]

18 hours ago, jhm said:

On the topic of data logging tools, has anyone had any first- or second-hand experience with the Racebox Pro?  (I didn't know this, but it's produced in Bulgaria.)

 

Seems to have a lot of organic features not inherent in many other data devices.  The biggest weak point I've come across is the app apparently, but the company seems to be improving it and releasing new updates regularly.  Overall, looks like a lot of capability for the money ($279 on Amazon).

 

https://www.racebox.pro/

 

I'd personally avoid this one as the software doesn't provide a desktop app.  Solostorm is probably a much better option and if you have any engine data from a swap then you'd possibly want to use an AIM solo DL or the racecapture logger.  It depends on what you need from it.  If you want something basic and lap timing Harry's laptimer is probably about as good as this.  

 

Cary

[jhm]

Yeah, I noticed that as well.  But it does offer the ability to export the data in a couple different format to allow analysis using other software tools.

 

https://www.racebox.pro/info/session-export

 

Personally, I’ve been using Harry’s and TrackAddict; but am looking to incorporate more sophisticated data logging/analysis capabilities this year.  Clark gave me a great deal on a DL1, and I’ve only just begun to scratch the surface with it.  Always on the lookout for new and interesting capabilities, and this one caught my eye. 
r/John

[clarkspeed]

Post #4 – Basic data systems, keeping it simple. 

 

 Now I will talk about something that can record data at least 20 times a second and allow you to review the data with a graph or chart.  Real analysis.  But what kind of system do you need? There is a wide-open field of devices that can do just about anything and new stuff being released all the time.  Electronics have gotten so cheap that even the most complex systems are affordable to a small racing program.  To start I will list the most basic data you will probably want to analyze performance. 

 

Lap time (segment times)

Speed vs. Distance graph

G-G graph.

Track Map

 

Many people are intimidated by this stuff.  But I think even the most tech adverse people can understand these 4 basics.  And I think most every data system available can provide this info.  Maybe you just need to watch a few YouTube videos on how to display this info.  Or ask a friend. You may never go any farther than this, but anyone with a data system should at least be able to analyze these 4 things.

 

I will briefly explain how I use these 4 basic data streams.  Lap times are the #1 measurement of motorsports.  Most competitions have some sort of feedback on everyone’s lap times so that is usually covered.   The nice thing about a data system is your times are recorded for you and can be reviewed right after you come off the track. There might be some programming required to set up for this.  Maybe it is pushing a button at the start and again at the finish.  Maybe it is downloading the appropriate track program that automatically brings in the start/finish line or it could be adding markers on a track screen.  Again, watch a video if unsure.  So how do you improve your lap times?  This should be obvious, it is going to take some experimentation..  A different approach to a corner, shift point, different tires, whatever you try needs to be backed up by a better or worse lap time.  So you will need to become a test driver and this is important. My term is ABE, Always Be Experimenting. The best drivers are experimenting all the time.  And they have a good “feel” for what works without waiting for the lap time.  They use other inputs and senses for this, not really a “butt dyno”.  Often it can be just checking the RPM you hit at the end of a straight or checking your location on track at your shift point.  Either way, you will need to record what you change, when you changed it, and what the results were. Along with any extenuating circumstances like passing another car.  Adding Segment times take this a lot farther and allows you to break things down.  It is much easier to look at a specific segment and keep all the other things that happen in a full lap out of your focus. Keep in mind though, track conditions can change.  The lap times you ran a month ago may be different now.

 

Next I will talk about Speed vs. Distance graph.  This really simple graphic can often tell you everything you need to know.  It is extremely powerful and by far the most used analysis technique and as far as I know, every system will provide it.  But the first problem you will run into is what are you going to compare your data to?  If you have the luxury of sharing data with others, this can be a great advantage.  Another approach is to share the same car with others.  The pro’s do this all the time with other team members.   Just overlay multiple data streams you can immediately see what the fastest approach to any given corner should be.   But this approach is not always available.  So I will go into some more detail on analysis techniques when comparing yourself to yourself since that is often the case.

 

An easy thing to say is maximize the speed on the graph.  Even better way to think of it as maximizing the area under the curve between point A and B.  Any line with a higher speed is reducing lap time. But you need to look at the big picture.  A higher speed trace going down a straight is most always a faster lap section.  A higher trace before a turn or in between 2 turns may not be the fastest way.

 

If just comparing data to yourself, look for Inconsistencies.  Good drivers lay down repeatable laps over and over again within a few tenths.  Think about why you are doing something different in a corner lap to lap.  What are you struggling with?  Could a change to the car make things better? Do you need a better reference point to focus on?  Are you focused on the right things?

 

You can also look for loss of traction or oversteer.  They tend to show up as a downward blip in the acceleration that is not due to gear change.  Look for blips between the apex and track out point.

 

Analyze braking carefully.  Transition from full throttle to full braking should happen very quickly and at the same point each time.  Speed should scrub off quickly and then level out as you transition into the corner.  Braking too late can cause the minimum cornering speed to drop off.  Braking too early can lead to soft pedaling the car and lost time.  Also look for “coasting” up to the brake point.

 

Early Apex or understeer will often show up as a longer time in the corner.  Full throttle acceleration happens later as you feather the throttle trying not to run off the track.

 

Other things can be seen in the chart like shift points, missed shifts, and loss of power. 

 

Next up is the G-G graph.  It is not nearly as revealing as the speed vs. distance graph, but can point to some time left on the table. 

 

A desired friction circle should “push” out the 2 upper legs of the triangle to more of a curve.  This is shown in the picture.  My feeling is the time between turn in and apex is the “magic” part of driving.  There is so much going on here and much time can be gained or lost.  The goal is to transition from full braking G’s to full cornering G’s while utilizing 100% traction.  Most drivers can corner at maximum G’s and know that feeling of slip angles being generated.  And maximum braking can be learned just by doing it over and over again and getting a feeling for what the car will give you.  But to ease off the brakes, while turning the wheel is a scary feeling.  It takes commitment that the car will hook up immediately as opposed to slowing down, turning, and the bringing up the cornering load slowly which feels natural and safe. The better you transition and will almost always lead to lower lap times.  

In addition, G’s are a direct measurement of the grip you have.  This can be a huge benefit when making changes to your car.  

 

And finally the track map trace.  This is pretty self explanatory but make sure you have good accuracy with your system when studying the lines.  And old data often does not overlay with new data so be careful when comparing over multiple dates.  Look at turn in, apex, and trackout.  Also consistency. And of course the sacrifice one corner for another corner type decisions. One of my favorites is to look for the shortest distance tradeoff.  Releasing the car to track to the outside of a wide turn covers a longer distance.  Especially big open turns.  Sometimes generating more G’s and maintaining a tighter turn will cover less distance and result in a quicker time. Same applies to going wide to set up for a turn in on a wide track.  It is also a big advantage to have the track map shown at the same time as the G-G Graph and the Speed vs. Distance graph.

 

Next (and last) post I will list out some of the options available and things to think about before purchasing.

[clarkspeed]

POST #5 and last. Advanced Data Collection and Analysis

 

If you want to go beyond the barebone basics then you have some tough decisions to make.  Especially if you are not familiar with this kind of analysis.  Before you go out and purchase something, you should think about what your requirements are.  I put together a list of some  options I am aware of.

 

1.     Does the software allow you to easily look at what you want to see?  Does it automatically  generate graphs you need?  Does it easily let you drill down in details? Do you need a configurable screen overlay? Do you want to create custom ways to look at your data?

2.     Do you need to download to excel? Time is money here.  The simple systems should spit out something you can use quickly if at an Autocross, and the most complex systems should have the ability to develop you own analysis screens so you can make decisions quickly based on complex data.

3.     Do you want to primarily analyze the driver inputs, monitor vehicle parameters, improve car performance or a combination of all 3?

4.     How do you want to display and interact with the data?

a.      Standalone box that records and displays data via. phone or built in screen.  Think about how quick you will need to access the data.

b.     Box that records data and downloads it over Bluetooth or Wi-Fi.

c.      Box that has a memory card you must remove and transfer into a laptop.  A little archaic and cumbersome.

d.     Box that transmits real time data over cell phone network (telemetry).  This is really nice for endurance racing.

5.     What is the “total” Price – software, connections, sensors

6.     Will you be sharing data with other people? 

7.     Do you want to combine with vehicle OBD II data?

8.     Do you have future expansion needs or are the basics enough?

9.     Do you want to combine with a dash readout?

10.   Does the system have the resolution and accuracy you need?

11.   Does the system have the ability to use at the location of your events. Is power available for a laptop?  Is the GPS accurate enough? Durable enough for desert racing? Boat racing?

12.   Do you want live driver in the loop feedback? I will talk more about this later.

 

Personally I think systems fall into 3 catagories. 

 

Beginner level stuff is usually cheaper and limited on what you can record and how fast you can record, typically 5-50Hz  Stand alone units like AIM SoloII, Garmin, and RaceBox have some great products.  They don’t allow additional sensors, but catch all the basics, are accurate, easy to use, and fairly priced.  Phone apps are also in this level and are a great place to start if you want to get a feel for the potential advantages of collecting data can do. But phones are more limited in analysis and the sensors are not as accurate.  Price < $1000.

 

Mid-level units are one step above. Usually record multiple channels and can interface with your CAN system.  50-100Hz is the normal sample rate here.  They have great software programs that can be simple or customized.  And math channels that can calculate your own variables. Typically interface with sensors you choose.  Most can be upgraded to something very close to a top level system.  Price $1000-$4000.

 

The top level pro systems are fully customizable and are suited to mate with pro level sensors and measure just about anything you can dream up.  1000Hz sampling rates are common.  They have multiple complex filtering options, telemetry options, dash, engine control, on and on.  $4000+

 

The hardware boxes themselves are fairly simple.  Usually only a few connections and if you are using external sensors, most systems provide plug and play capability.  High end automotive sensors can be expensive but as mentioned earlier, cheaper substitutes can be put together using simple materials like load cells and potentiometers.  String pots are a good universal sensor for movement and can be purchased used.  Even if using custom sensors or adapting OEM sensors they are usually only 2 or 3 wire connections (+/-/Signal).  Most all boxes have accurate GPS location and high-fidelity G sensors.  This usually requires a flat mounting near center of car.  Some even include a yaw sensor.  The main differences are how many sensors it can monitor (channels), how many samples does it take per second, and does it have a CAN interface to monitor vehicle functions already available. 

 

The higher up the ladder you go, the more technical the systems become.  Most all can be used at a basic level, but to fully utilize the software usually requires an engineering degree.  The analysis software is a very important interface. 

 

If pure driver improvement is your goal, then one of the best features you can get is a way to provide direct driver feedback. Think about a coach sitting next to you telling you to brake later or carry more speed here.  And as I mentioned in an earlier post, by far the largest component of faster lap times is driver dependent.  I became addicted on this technology while driving iRacing sims during the pandemic.  iRacing provides a live readout of slip time to your best lap and more importantly, a bar graph of the slip rate.  The slip rate is how fast you are losing/gaining time to your best lap. An example would be if you spin the tires on corner exit and lost 0.5 second quickly.  You would see the red bar max out the graph for a moment.  As you gather the car up and accelerate down the next straight you would see the bar graph just very slightly in the red zone as you lose a small amount of time all the way down the straight.  If you perform a sequence better than your fastest lap, you get a green bar. Simple and very effective.

 

I believe all the higher end systems provide this feature sometimes depending on also having their display.  On the low end one of the more innovative systems is RaceBox.  Just a simple red/green bar graph is the only output.  But complex programming runs in the background to filter out the noise and make it as accurate as possible.  Another interesting unit is the Garmin Catalyst.  It provides an audio instruction on where and how to go faster.  The Garmin has it’s own screen and quick drill down graphs to show the time differences.  There used to be another stand alone audio coach unit but I could not find it on a search.    

[Mikelly]

Been a while since I have posted on HZ.  I ran into Jon (JHM) at Dominion yesterday. I've been coaching and instructing with a number of groups, and I've got approximately 6 regular clients I coach, and a handful who pay me periodically to review their data and footage.  Some of the tools and systems I use:

 

Harry's Lap timer (still a good and cheap product that incorporates your phone's camera) - Limited data based on your accelerometer and GPS.  Down side is no sensor driven data.

Traqmate - Still a great option, if you can find a working traqdash, even better - Down side is they're out of business and have been for a long time.

AIM - The best and most comprehensive system I've used and I've got two in two racecars IN HOUSE - Down side is cost and complexity of the software.  Tons of help, but it requires commitment to learn to use and isn't "easy" out of the box.

Garmin Catalyst - The best "beginner" device going right now, but honestly, it's a fancy tablet based "Harry's lap timer" with some limited coaching functions in a tablet form.  Us instructors like it because we can share data and build profiles for multiple users on the same device and then compare the data among drivers.  It's still "not" cheap at about $800 to get all in with camera/wiring harness/tablet and mount.

Racebox - I've used this one time only, and it seemed like a competent device. We ran it against Harry's lap timer and both read identical data. It's limited and the mount was a little finicky.  For the money, I'd just use Harry's lap timer.

 

Of course, cameras are a part of the mix, and you can spend a small fortune integrating a system to utilize the data overlays for the cameras (I'm looking at you, AIM). One of the things that Garmin does well is integrate the data and video together for easy review and uploads to SM.  For those still using go-pros (I am one), Racerender is a nice way to stitch the data together with the video, if you are patient and have the desire.  The instructions can be a little clunky and if importing AIM data, you need to convert the channels to CSV first. 

 

With, even the most season'ed racers, I've found many people only want a few bits of data.  I log 14 channels on my 968 powered 951 racecar, and we log 8 on the 944Spec.  Most people want RPM, Brake, Acceleration, speed and lap time.  If you're going to use your data logger to diagnose problems (like I used to on Sasha Grey) then you'll really want more than just the basics.  OIl Pressure, oil temp, coolant temp, Amp or Volt, EGR, AFRs all can go a long way towards helping you keep your given platform in check.

 

 

Do you want to learn how to read data? 

I recommend to my clients to get iRacing and VirtualRacingSchool.com.  Then Use both in tandem to learn a given track in a given platform.  ALL of this data directly translates to reading data and comparing your laps and data to your coach's.  I've found this translates into real life with most of the more popular systems out there.  Happy to help, or weigh in further, but I'm best reached through email as I'm never on here anymore.  dat74z At Yahoo.com

Edited November 12, 2023 by Mikelly

[clarkspeed]

Thanks Mike!  Glad you are still lurking around!

[tube80z]

13 hours ago, Mikelly said:

Of course, cameras are a part of the mix, and you can spend a small fortune integrating a system to utilize the data overlays for the cameras (I'm looking at you, AIM). One of the things that Garmin does well is integrate the data and video together for easy review and uploads to SM.  For those still using go-pros (I am one), Racerender is a nice way to stitch the data together with the video, if you are patient and have the desire.  The instructions can be a little clunky and if importing AIM data, you need to convert the channels to CSV first. 

 

Hey Mike, great to hear from you.  I'd also take a look at https://www.race-technology.com/gb/gopro software for pulling data on most newer gopro cameras.  And if you want to be able to mix and match data Track Attack is nice software to use.  It also can integrate most action cameras into a feed with overlaid data.

 

Cary