How To Compare Your Racing Laps Using Google Earth

If you compare your racing laps, either against yourself or a teammate, it is a great way to improve your understanding and your lap-times as a racing driver.

Luckily there are plenty of tools to help you compare your racing laps. Many people run data loggers (such as the AIM Solo, VBox or Race Technology DL1) with GPS and other sensors able to show you all manor of precision information.

The issue is that data logging systems are tricky for people to use. They are engineering-grade bits of kit, with software to match and the resulting data they give you needs a lot of interpretation.

Comparing laps with video

Many people focus on using video instead. It is easier to capture, quicker to access and very intuitive to understand.

The benefits are that it more easily enables a discussion on say different racing lines, braking points and even highlights any obvious areas where the driver could use more (or less!) of the track.

When using video it is also clear when another racing car may have influenced the lap time, either by blocking or assisting progress.

Video alone though is quite a crude approach to use to compare your racing laps.

This is especially true when you are trying to find the last few tenths of a second and when maybe there is a choice of corner approaches, gears and good looking racing lines.

Data loggers do pretty much hold the answers but even when combined with the video, they still require knowledgable interpretation.

It is also fairly slow plus many people, in my experience, are just not that comfortable translating squiggly lines into something meaningful they can put into action on the track.

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Intuitive Data Visualisation

What would be better is to have a way of presenting the more precision and detailed data logging data in a more easily digestible way.

By having say lap time comparisons visualised more intuitively for people, it should enable racers to get more value from their data logger investments ensuring they become more than just expensive lap timers …

A few years ago I was doing some work with a professional Le Mans race team. They had a wealthy owner-driver who was not comfortable with reading race data logging analysis charts.

We, therefore, came up with an idea of presenting lap comparisons using a path displayed on Google Earth. Not only does this allow interaction with a familiar map style interface, but the path could also have “features” to make it even easier to understand.

Features include numbered labels, colours and a path height based off the data.

Recently I saw a post someone had put on a racers Facebook group showing their paths around Google Earth. I thought I’d share my version here to compliment that and explain how you can do compare your racing laps like this too.

Compare Your Racing Laps Data in Google Earth

Below is a video showing you the challenge described above and the outcome we are aiming for. Hopefully, you will see that it is quite an impactful way to compare your racing lap data.

Video notes: To avoid confusion, here is some information to help you understand the visual:

• The video shows the data from a slow lap compared to a faster lap.
• The slow lap was [1:18].65
• The fast lap was [1:18].02
• The difference between them is therefore 0.63 seconds
• The question is: “How and where were the 0.63 seconds lost.”
• Whilst the 0.63 seconds is “lost” in the visual this is shown as a positive number.
• When the path rises, it shows where the slow lap was losing time verses the fast lap.
• When the path descends, it shows where the slow lap was gaining time verses the fast lap.
• This may be the inverse to what you’re expecting (or not!) but I’ve had some comments thought so best to clarify.
• Ignore the colours red and blue. They should show the gain or loss but something doesn’t work on this towards the end so just ignore them.

Below is a quick step-by-step guide to help you create this yourself.

Note: I use the Race Technology DL1 data logger so the data export example is for that system.

Step 1: Data Export

• In your data logging software select the laps of interest with the reference for the “time slip” or “lap delta” comparison channel.
• With Race Technology, this is done by selecting the reference lap (by clicking the circle next to the lap time) and then selecting one other lap to compare that against (by clicking on the lap time itself).
• You should have one lap’s worth of data displayed with the time slip channel comparing against your reference lap:

• Select “File -> Export as data” or the equivalent.
• You’re likely to have some options here.
• Choose export to CSV. You don’t need the data at more than 10Hz frequency given that it is just a visual.
• In Race Technology this involves changing the number in the “Sample time for exported data box from “0.01” to “0.1”. In other systems you may be able to select the Hz directly.
• In Race Technology you then choose “Export Highlighted Section” and click OK.

• Choose the folder directory and give the file an appropriate name to save it as.

Step 2: Data Clean-up

• Google Earth Pro likes the data in a simple table format. This means the top row should have the header information for the column of numbers below it.

• The Race Technology CSV export has the first 5 rows for some general information about the CSV. These need to be removed. I do this in a spreadsheet by selecting the rows we don’t need, right-click and then selecting “Delete”.
• The CSV file also has a large number of columns of data we are not interested.
• The only ones we want are “GPS Lat”, “GPS Long” & “Time Slip” or their equivalents in your system.
• Remove all the channels you don’t want by selecting the columns in a spreadsheet, right-clicking and then selecting “Delete” as you did for the rows.

• Save it as another CSV file.

Step 3: Import into Google Earth Pro

• When you have cleaned up your CSV import the data into Google Earth Pro.
• Open Google Earth Pro then select “File -> Import …”
• Select the CSV file you just cleaned up and click Open.
• If you have ever imported a CSV into a spreadsheet this next bit will be familiar.
• Look at the preview of the data in the panel at the bottom. If the columns are appropriately split then press “Next”.
• Note: In the file below I also imported the “Speed” channel to see what that looked like too. I’m also using a Mac but the process is the same on Windows.

• If not then adjust the delimiter settings until the columns have separate Lat, Long and Time slip columns.
• If need be go back and to step 2 to create a more cleaned up CSV file – remembering each column needs a header label in the top row of the file.
• Next select which columns relate to the Latitude and Longitude fields.

• Click “Next” and double-check the field types are correct for each of the columns. They should all be of type “Floating point” which basically means they are decimal numbers.

• Click “Finish”

Step 4: Apply a style template

• When prompted, click “Yes” you do want to apply style template. This will enable you to specify the “features” that can add to the pure path data.

• Click Ok to “Create new template”.

• If you have done one already click “Use existing template” I discovered that when you do this, you also get another option to edit the existing template which is useful if you just want to make minor tweaks.

• In the template you can now select how to present the data for four areas: “Name”, “Color”, “Icon” & “Height”
• Name is like the label you want to be put at each point.
• Select the “Time Split” column in your data from the drop-down box.

• Color is the colour of the bars you and icons you see.
• Again you can select a field, to use a single colour, or random colours (!)
• Icon is the icon shown at each point.
• This can be useful I imagine for showing progression and again you can set this from a field if you like.
• Height sets the height from the ground of the path.
• This is really the key one. Select “Set height from field” and choose “Time Slip”.
• Choose “Continuous” and then adjust the scaling factor. In my example, I tuned it so that the maximum was 100m high.

• Click OK and your path should appear!

Bonus Step: Create “Tour” to share with others

• If you want to create a “Tour” like in the video have a look at this link.
• It is quite easy but you need good mouse skills (better than mine!)

Summary – Compare your racing laps in Google Earth

Motorsports data logging data and video systems do tend to hold all the information and more that you need to compare your racing laps. However, they are time-consuming to work with and the end results are not always easy to interpret.

Whilst getting the logged data into Google Earth is clearly another step, the benefit is that once it is in, I feel that the visualisation is really very powerful. By comparing your racing lap GPS data with the time slip, even the more subtle the gains and losses are straight forward and clear to see and understand.

In our case the simply action plan resulting from this analysis is:

1. Have a bit more bravery into the left-hander at the end of the straight “Rocket”.
2. Try second gear at “rocket” if needed in the race.
3. Make sure to brake a little less hard through the downhill corkscrew section.

As the driver, you just need to execute on the plan by combining all that and there might be even more time to be had.

By no means the definitive solution but hopefully a useful approach to try with your own data.

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Want to take the guesswork out of setting your tyre pressures? Try this article including a free calculator: https://www.yourdatadriven.com/how-to-set-your-racing-car-tyre-pressures-perfectly-every-time/

Wondering what the tyres are actually doing? This article should help your visualisation:https://www.yourdatadriven.com/tyre-slip-angle-explained/