Hi there...
being a complete novice with autopilots and quadrocopters in general, I just got my stock 3DR kit completed and was able to fly.
Some observations that might help newcomers to get the stuff together:
- If you think you have checked everything - do it again. There's certainly something you missed.
- Getting the right motor connections to the PDB board is a nightmare. Even if you follow the instructions, you almost certainly end up with a wrong order of motors. Even if the CLI motor test works as per instruction, it might still be wrong. I had to switch front and back motors to make it work. The best test ist the "hand test" - hold the copter over your head and apply some throttle. Feel how the copter reacts to movements. Even if you never have done this before, you will feel when it is right. The copter will feel incredible stable in your hand. If it just does "something", then there's probably something wrong.
- To change the order of motors, instead of disassembling the frame and to resolder the PDB, I just swapped pins in the connector from the motor output of the APM to the PDB. Much easier.
- I had to reverse the pitch channel on my R/C. Don't know why, but when I pulled the stick, the back motors increased speed instead of the front motors.
- Definetly think about getting telemetry - flying the copter is so much fun, you will need the battery monitor ;)
So much for today - need to update the copters firmware ;)
Michael
Comments
I had the "shifting battery" issue as well. Putting some velcro to the battery seems to be the best solution - I was thinking about something more complex - sometimes you just don't see the obvious...
Regarding the frame weight - I'm glad it is as heavy as it is... Parallel to the 3DR frame, I built a self-made frame from 10mm aluminium tubes, with a KK controller. It flew as well. Once... With roughly the same motors as the 3DR it just skyrocketed into the air... Out of surprise, I cut the throttle and made a nice gravity assisted landing on a road nearby ;) I'll see that I make a picture of the (now) tricopter. The whole flight didn't last any longer than a few seconds, but the copter was already about 30m up in the air, disappearing behind the roof of our home.
Hello
Thank you opened this discussion
I also had problems with the connection of the motors, and after 3crashes I double checked all the connections again and I think Ifound the problem was the connection APM. When I made thefirst engine test rather than reverse the connections I havechanged the configuration of the RC (Graupner MX-20).
As soon as I have time I do another test.
I really like the sturdiness of the frame, even if it seems heavy.
I have another copter, JDrone, and the comparison of the weight is considerable.
I would like to contribute to the discussion with my experiences ...
See you soon
Garrick: You should stick some velcro on the battery, too, so the strap has something to grip onto.
I had similar confusion with the PDB orientation as well as having to reverse the pitch channel. I have a couple additional comments about the 3DR frame:
The velcro battery strap is not sufficient to hold the battery on its own. I've had several flights where I thought I was having drift issues, only to find out once I landed that the battery had slid an inch and greatly affected the center of gravity.
I've had drift issues that seem to be solved by isolating the APM from the frame with a combination of rubber and felt washers. I know vibration issues with the APM are common with most frames and what works for one person may not work for everyone, but I think some form of vibration isolation in frames designed for an APM would be helpful.
Thanks, that's helpful. I'll pass that on to the hardware team.
I am happy to follow that request. For me, one of the problems was that while the instructions say something like "this side should be mounted downwards". But at that step in the process you actually have the frame upside down - the PDB on top of the base board.So, should the PDB be mounted upside-down on top of the upside-down base board - or should it be upside-down when the frame is sitting in it's final orientation.
The other "problem" is that you don't know which connection belongs to which motor. Using motor numbers doesn't make thinks easier.
In my opinion, it would be incredibly helpful if next to the power and control connectors would be labels like "F/FR", "R/RB", etc. identifying the position of the motor. That way you could tell immediately in which orientation the board has to be mounted and which color of the APM connector corresponds to which motor.
Glad you got it running! Any specific feedback on the PDB assembly instructions and how they could be improved would be very welcome.