Quad Update #2

I’ve spent a bit more time with both Paparazzi and the KroozSD board, so these are a few more observations.

NB these ONLY apply to the KroozSD board 🙂

Configuration

After a good look through I changed the settings to match my configuration, tweaked a few to what I hoped would be more appropriate values and rebuilt. The ESC’s now make the correct noises and the telemetry looks good. The battery voltage being shown is that supplied via the BEC built into the ESC‘s, which is essentially 5V, so I had to adjust the battery warning levels to prevent the constant warnings. I’ll need to add a battery sensor to address this.

USB

When powered up, plugging in a USB lead doesn’t provide any information. Powering the board with a USB cable attached does provide a connection to the bootloader, as expected, but the lack of connection from the board when powered struck me as odd. Thinking about it more, there is no reason why the board should power the USB when it’s going to be as far away from a computer as it is! It’s possible to build a firmware that does have a USB connection when powered, but it would only really be useful for testing.
Having built such a firmware and loaded it I found that my next attempt to flash firmware failed as the USB connection was being made with the running firmware and not the bootloader. Watching the board more closely I found that LED 1 would be solid red when the bootloader was connected and ready for new firmware to be uploaded.

Calibration

The configuration file includes some default calibration values, but these need to be replaced by values for the my own board, so time to look at calibration. Prior to doing this I had a look at the PFD (Primary Flight Display) tab on the Paparazzi ground station to see how good/bad the initial values were. The result was it showed the board in a climbing left hand turn, but the right way up. Moving the board also showed the expected responses.
Calibrating the accelerometers is the first step and proved to be quite simple, though I’d suggest reading the “Basic procedure” description and generating a log file a few times before using trying the actual calibrations.

Accelerometers

Put the board in the correct orinetation, hold for 10 seconds, move to next one… Relatively easy to accomplish once you figure out the order of the orinetations as shown in the supplied image (below).

Reading the text and comparing it with the image made things clearer but the image could be better. I did the tests with the board secured in the quad as it made moving it around easier and allowed me to reinforce that I had it correct way round!

Once complete, I ran the script and had some new calibration values. Once the configuration file was updated, firmware built and uploaded the PFD showed level wings and nose – exactly as expected.

Magnetometer

I’ll do this over the next few days, but ran out of time yesterday.

Gyroscopes

I’m sure this would give much improved results, but the procedure outlined looks…complex! I’d be interested to know hos much improvement it makes?