PX4 Pixhawk Lite - GoodLuckBuy

[Hands0n]

As the title states, this is about the PX4 Pixhawk Lite from GoodLuckBuy.

See --> http://www.goodluckbuy.com/px4-pixhawk-lite-v2-4-5-32bits-open-source-based-pixhawk-compatible-pixhawk.html

The package sent consists of what you see in the picture below (click picture to see larger a version)




Two versions exist, hopefully no one gets the V1 that had some "quaint" wiring of the Power Module port that would likely result in magic smoke!  That has been corrected in the V2 that is now shipping.



I went for this FC to fit into a 300 folding frame from makeitbuildit.co.uk, the plan being to build a travel friendly camera ship.  A scaled down Pixhawk seemed most appropriate to my needs and experience.

Along with the Pixhawk Lite I also ordered an M8 GPS unit.   Here';s where the trouble started.  The GPS cable is made up for [possibly] APM and needed some re-jigging to get it working with the Pixhawk Lite.

Magnetometer
The blue and white Mag wires that hook up to the i2c port are reversed, SDA and SCL.  So you need to carefully remove the two wires and reverse them in the plug. 

GPS
These wires in the plug are completely wrong.  How I didn';t get magic smoke I don';t know.  The power wires (red and black on this cable) need to be reversed. The GPS puck got warm but thankfully did not commit suicide!

The TX/RX data wires are also incorrectly wired for the Pixhawk Lite, connecting by default to the Telemetry pins of the multi-function socket on the Lite. You need to remove them from the plug and shift them up two places...

Topside of Pixhawk Lite


Note that if you are also going to use GPS2 that the pinout on that port should be carefully checked against your GPS to ensure no problems.

Underside of Pixhawk Lite



Signal Connections
The only other thing to note is that the pins for the Input and Output are wired up so that the Signal pin is at the top, with 5v in the middle and Ground at the bottom pin.

[attachimg=1]

Software
I have loaded up the current version of ArduCopter, that being 3.2.1 and it has configured okay, calibrations for Accelerometer and Magnetometer(s) were trivial as usual. 

There was some talk on RCG about this FC having an issue with 3.2.1 but that has not manifested on the V2 board that I have here.

A review on RCG said the following:

First note is that it came loaded with 3.3 Dev firmware. I found this curious because the current stable release is 3.2.1 not 3.3. It appeared to work fine though. I then loaded 3.2.1 and rebooted. I got a bad gyro health message on the HUD. I proceeded to do an accelerometer calibration and a compass calibration without issue. But the Bad Gyro Health message remained and the updates in Mission Planner were quite slow, abnormally so.

I then installed beta firmware 3.3 rc4 and rebooted. No bad gyro health message. I then did the calibrations and the board seemed fine. To verify the test I returned the board to 3.2.1 and the bad health message returned. Then back to 3.3.rc4 and it was gone.

My conclusion is that the board needs something fixed in 3.3 and that is why they delivered it with a beta version of the firmware.

Citation: http://www.rcgroups.com/forums/showthread.php?t=2418029

I did not experience this at all, so mention it here so that anyone reading this may be aware.  If you see odd behavior then update to 3.3 beta - or the full version of 3.3 if it is released by the time you are reading this.

Ready to go?
I think so. Everything checks out as it should.  The next steps are to mount the FC and power train in the 300 and get it maidened. 

[JeremyE]

Ah interesting, I went for the mini Pixhawk. I need the 2nd telemetry port for some GPS gimbal tracking. I will have to double check all the wires that come with it though so that I can avoid any magic smoke!

[Hands0n]

Ah interesting, I went for the mini Pixhawk. I need the 2nd telemetry port for some GPS gimbal tracking. ...

This one (the PX4 Pixhawk Lite) also sports two Telemetry and GPS [combination] ports.  I';m not sure about the Mini Pixhawk (or is it Pixhawk Mini ) but the Lite has omitted a few bits, the buzzer being the one thing I actually regret not being there.

I will be attempting to use the i2c to fit a remote LED which is going to be very useful to be able to observe the FCs various status while in nearby flight (similar to Naza FCs).  Otherwise, once airborne, there will be no visual indication of the FCs status.