[miker]

I'm trying to convert one of the basic brushed quads like this one:
https://www.amazon.com/WLtoys-V929-Beetle-Quadcopter-Dexterous/dp/B008RL18SM

With:
CC3D Atom
DJI Phantom PPM receiver
ReadymadeRC quad brushed ESC - http://www.readytoflyquads.com/brushed-motor-driver

So far the PPM input is working fine, and the motors basically work.  From reading other threads, the motor controller is a "pure" PWM - it runs directly on the duty cycle, not a scaled 1000-2000us RC PWM.

I have my motor outputs configured at for 0-2000us @ 500Hz, and when I tweak each one individually I seem to get full power.

My problem comes when I try to "fly" it.  When I throttle up, one one or two of the motors will spin up and it wont have nearly enough thrust to get off the ground, but if I pick it up and tilt it, the appropriate motors kick in and will push hard to try to level it.

If I put in any other command - pitch, roll, or yaw - then the motors will spin up.  Why is it so sluggish responding to throttle?

Another issue I'm having, and I'm not sure if its related, is that none of the arming options work - low throttle, and left yaw, or full forward etc. don't arm it.

I've attached the .uav file, if that helps.

[miker]

OK, so after more reading, my arming problem may be due to the config warning.  Here's my problem - it tells me I have set up a GPS mode (but I don't think I have) to go to "GPS Navigation" in "config->attitude" which isn't there, and a stabilised mode is using a wrong thrust mode, but they are all using Manual.

[hwh]

The message is just examples of the type of thing that could be wrong.

The problem is your first flight mode is "Land" mode.  Change it to stablilized1.

[miker]

I fixed that after I made the last post, but forgot to upload the new .uav.  Even with that on "Stabilised" instead it gives me the same warning, wont arm, and still misbehaves w.r.t. throttle.

[hwh]

The throttle may be because of the settings you're using, take a look at https://forum.librepilot.org/index.php?topic=1597.msg11639#msg11639

The warning goes away on my system when I change land to stabilized1.   Are you sure the change is being saved to the board?  Because of the odd output settings I couldn't get the change to upload to the board.  I had to edit your uav file with a text editor and change land to stabilized1, do an upgrade and erase, and then load the edited uav file back in.

[miker]

OK, will check.  Seems odd that the motors do seem to be fully responsive to anything other than throttle.

[miker]

It's alive!

The motor problems were due to my mistake.  I initially had the motors running off the 5V step-up converter, but they'd brown out the receiver.  In my infinite wisdom, I attached a second battery directly to the motor controller ... but didn't couple the ground to the rest of the system (the controller inputs are single wires from the PWM outputs.

I reckon that's what was causing the odd behaviour. Once I rewired that, all the motors spun in sync.

You were right about the flight mode - for some reason my getting rid of "Land" mode hadn't stuck before.  When I booted it up tonight, it had changed to "Manual", so I set it back to "Stabilised" and it would let me arm.

Took it outside, and it FLIES!!!

I need to find a bigger space to do some proper testing, but the little bit of flying I did was very promising, even with the generic PIDs!

Thanks for the help.

In "Scope" is there a way to monitor the RC inputs?  I can't see it.

[jinp]

Hi
How do you have motor outputs configured at for 0-2000us @ 500Hz? I can only set minimum motor output to 500us, and update rate only have 270Hz. 330Hz, 490Hz...

[miker]

If you go through the "System" tab, you can change all the parameters directly without being constrained by the GUI.  Remember you need to change the frequency for the second "bank" of outputs.

Once you do it, you can no longer use the output tab to adjust anything else.