BigQuad - All fine, just M1 is lazy

[Konstantin]

Hey Bitcraze-Team,

The BigQuad Deck is absolutely fascinating! I bought some big parts and build a big copter (couldn't name it crazyflie anymore, it's rather Crazybird). Everything connected (cf without battery, bigquad attached and connected to the escs), firmware modified and flashed. Well, as I give some thrust, the Motors (without props) run strong and fast - expect M1. This Motor seems shy, it doesn't move. I changed the connections at the BigQuad (M1< --> M2), M2 was silent after that and M1 was running.

So: escs, Motors: Check!
The Problem seems to be at the M1 connection of the Board. I checked the Connections with a Voltmeter and there were some differences, which I'm going to post later. Firmwarecode is an untouched one, expect BigQuad modifikations described in the Wiki + change from 400 hz--> 1kHz, cause escs are running with 1khz. I'll post this change in the code later, too.

Does anyone have a first idea, what might cause the issue, or what to do for troubleshooting?
Thanks in advance to everyone, who might deal with this!

[Konstantin]

Here are the values given by the voltometer:

Seems like the values of the M1 connection doesn't change during startup..

[Konstantin]

I had a closer look at the board and hit on something, showed in the red circle. Does these soldered point should be unused/free?

[Konstantin]

Okay, i solved the problem! I noticed, that the soldered point on the CF board had an unstable/broken connection to the connector. I fixed it by soldering and now it's flying! Well, the PID values seems to need some adjustment, but hurray, it works!!

[tobias]

Great troubleshooting! (A bit worrying this passed production tests though as there are tests for this...)

The unmounted capacitor (C2) is for optional current monitoring low pass filter. The schematics is here.

As for tuning you currently have to hard code the changes in the pid.h file. In the future the idea is to save them in the 1-wire memory so it will automatically use them when the CF2 is connected to the BQ deck.