Data Logging Through Driverstation

[OwenDotCode]

We have considered both of those, but our issue if will those still work if the robot loses power?

[OwenDotCode]

Also we are using Java

[bobbysq]

Originally Posted by OwenDotCode

We have considered both of those, but our issue if will those still work if the robot loses power?

If you log to something like a CSV as the data is collected, power loss shouldn't affect it since it'll only add one line at a time and it's a plain text file.

[phurley67]

Try it now (sorry about that, the repo was not supposed to be private).

[OwenDotCode]

Quote:
Originally Posted by OwenDotCode
We have considered both of those, but our issue if will those still work if the robot loses power?

So would the CSV file be saved every time another line is added?

Thanks for the like to the Valkyrie, I will talk to my team about it at our next meeting.

[phurley67]

Our code will create a new file (with a new header record) every time the robot code restarts -- if it due to power loss, redeploy, or restart. It is pretty trivial to join a couple csv files either using bash script or in an editor.

Right now we are using sequential numbering, as we did all our off season testing using the qdriverstation and the date/time on the rio was not getting set. Probably going to change that, but it works as it (plus if the date is set the file's timestamps will be accurate).

[Greg McKaskle]

There are a number of good suggestions in this thread, but let me add a few points.

The OS and other utilities log things to the roboRIO flash all the time. A team is running with user privileges It should be pretty easy to look at your log file design, estimate usage, and determine whether a USB stick or RIO flash is the right approach. Also, if needed, you may want to disable buffering to on file open to better deal with power loss.

If you find that your CSV file is too large, binary files are often much smaller, typically a factor of five to ten.

Depending on the rate you want to log at, you may also want to consider network table logging. This logs the data at more like 10 Hz, but it automatically logs every variable update and it is built into the default DB. It is possible to build a custom DB and log faster if you wish.

I highly encourage you to log data, though. I love it when teams have data to understand what their robot is doing.

Greg McKaskle