Monthly Archives: March 2014

Version 19 is out!

Posted on by Dirk

19As the title says, we just released version 19. What happened to 18? Well, occasionally we ship small bug fixes that fix just one or two critical issues that made it through our filters. We don’t want to make a big deal of every little bug fix we ship, so there was no announcement for it. It’s a shame, really, because we had a great picture lined up for version 18…

Anyways, version 19 is a collection of smaller fixes, most of which suggested by you guys:

  • Code signing on Mac and Windows. For you, this means there are no longer any nasty warnings when you install the software, and on Mac, you don’t have to change your security settings anymore to install Off Camber Data.
  • The names of drivers, tracks, and cars/karts are now case-insensitive.
  • The graph now saves and restores its settings across restarts, and also when you switch away from it (to look at split times or min/max values).
  • A few GPS related fixes:
    • On the UniGo, the GPS data has a delay of about a quarter of a second. The software now recognizes this and corrects for it.
    • When the GPS signal drops, the software now automatically detects this while importing the files, and switches to the speed sensor to produce accurate delta graphs and distance graphs. If the automatic detection gets it wrong, or if you already have imported files with problematic GPS data, you can fix it. Right-click on a run, click “Edit run”, and select or deselect “Prefer GPS Distance”.
    • There were a few crashes related to broken GPS data. To our knowledge, we fixed all of them.
  • Driver names are now editable. They always should have been.
  • When you export channels, the channels are now in alphabetical order. Also, there are two new buttons to quickly select all channels, or none of them.
  • We now correctly import the battery voltage from the Unipro 6003 (together with all other channels, of course).

To get version 19, head over to the downloads page!

As always, please let us know about feedback, either directly here on the blog, or at feedback@offcamberdata.com.

Formula 1 start of the season

Posted on by Dirk

To celebrate the start of the Formula 1 season, here is an interesting picture of the new Red Bull:

In front of the wheel, in front of the slats, you can see a little bulge. That bulge houses the tire temperature sensors.

In front of the wheel, in front of the slats, you can see a little bulge. That bulge houses the tire temperature sensors. My guess is that they’re infrared. We’ll hear more about these temperatures throughout the season. In fact, it was already the focus of a discussion Hamilton had with his engineer over team radio in qualifying.

 

What is slip?

Posted on by Dirk

When configured for karting, the Off Camber Data software will show “Slip” as one of the channels that can be graphed. In this article, I will briefly explain what the slip graph is and how to use it.

Slip compares the speed of the wheels with the real speed of the kart. When the speed of the wheels is higher than the speed of the kart, that means there is too much throttle, and the tires are spinning. When the speed of the wheels is lower than the speed of the kart, that means the driver pushing the brakes, maybe a little too hard. When slip goes to zero, it means that the tires are locked.

A lot of the time, slip will be mostly constant. When braking, it will dip down. When accelerating, it will tend upwards. This is especially true in the rain, when the driver can get a lot more wheel spin than in the dry.

Slip Graph Illustration

This graph shows RPM, Slip, and Speed together.

Consider the graph above. The interesting part is the right half, after the main straight. Once the driver hits the brakes, RPM jumps down, but speed takes a while to catch up. As a result, the slip graph dips down. You’ll notice that at first, it dips down sharply, but then goes back up a little, staying below its normal level for a while longer. That shape is the hallmark of skillful brake application. Of course, the true way to judge brake application is to use a graph for longitudinal acceleration, which is not shown here.

After the braking maneuver, you see two large spikes. This happens when the kart jumps over the curbs. The rear wheels are getting unloaded, or even leave the ground altogether, while the driver keeps his foot firmly planted on the gas pedal. The wheels start spinning, and you can see that as two sharp spikes in the data.

In the current version of Off Camber Data, this channel only makes sense for karts, and only if the sensors are configured correctly. In particular, to measure the real speed of the kart, it uses the speed sensor on the front wheels. To estimate the speed of the tires, it uses the RPM sensor on the engine. This method only works if the speed sensor is on the front wheels, not on the rear wheels. Also, both brakes and engine have to act only on the rear wheels. Finally, it does not work on shifter karts.

With time, we will overcome these limitations. Please leave a comment or email us if it is important to you that we fix this sooner rather than later. We are always available at feedback@offcamberdata.com.

Version 17 is out!

Posted on by Dirk

17You might be wondering, what happened to versions 1 through 16? Well, they have all been released as well, but I’ve been grossly remiss in posting updates about that to the blog. No more! From now on, we’ll be announcing every update on the blog.

Without further ado, here is what’s new in 17:

  • Tracks, drivers, and karts/cars can now be renamed.
  • The import dialog used to show a progress bar while moving from file to file. That’s confusing, because people thought it was still importing, when really it was waiting for user input. We rearranged the import window and removed the progress bar, to make it clearer what’s happening.
  • We now automatically select the best lap of a run if no other lap is selected.
  • Sample data! A fresh install now comes with three pre-imported runs, so you can play with the program before you drive.
  • Added a button to manually check for updates. Usually the update check happens automatically in the background, and it prompts you to update when the program exits. Now, you can also trigger the update check by going into the “About” dialog and pressing the update button there.
  • OCD export/import. You can now export runs into the OCD format, and then import them again later. This is useful if you want to send data to your friends and colleagues, and if you want to have the same data on multiple computers.
  • Full-screen mode
  • Made the export dialog show only relevant channels
  • Channel Management had some confusing issues. Many of them have been cleared up, but some still remain. We had to leave something to version 18 🙂
  • Fixed problems with broken or truncated files, which can happen when the lap timer freezes, or a sensor dies or loses signal during a run
  • Cosmetic improvements

To get this tasty new version, head over to the downloads page!

As always, please let us know about feedback, either directly here on the blog, or at feedback@offcamberdata.com.