Building a quadcopter – Electronics

This is how my Workspace looks after a few hours of debugging 🙂

I did some work on quadcopter-frames in the past, so inspired by the NG-UAVP-Project i decided to build my own quadcopter.

Since those guys offer blank PCBs i ordered some and build a Flight-Controller (hw0.24-mini-r2) and a Quad-Brushless-Controller (ngblc-r2). After some trouble with customs/taxes and missing parts i was finally able to assemble and test both boards. As always not everything works out of the box (soldering errors, missing parts, …).

• Make sure to populate R68/R69. Those are current-limiting resistors for the backup battery for the Venus-GPS and the RTC. I left them open in the first place sind i didnt populate the battery. However, the Venus-GPS needs power at the Vbat-Pin to work. I spend about 3 hours searching for errors in the serial-communication :/
• Check the supply voltages of each chip. The coil in the the LC-Filter for the MPU-Accellerometer was broken; however the MPU somehow still worked (eg got some supply current over clamping diodes), but did not answer SPI-requests correctly.
• Cabeling is also an issue. The picoblade connectors are nice and small, but sometimes dont give good contact. I had some issues with the external-i2c-sensor bus because one pin didnt provide good contact.

There are still some open issues:

• The LIS3L-Accelerometer wont get recognized on the SPI-Bus
• On the ngblc there seems to be at least on misplaced part. On of the supply-voltages drops down because of overcurrent. I am still investigating this.

As next steps i will finish the mechanical setup. Mount the motors to the frame and do some wiring.