Version 2.5 of the ArduCopter code is now available in the AP Mission Planner and in the downloads area!
The default PIDs are optimized for a 3DR/Jdrones quad with 850 motors and 10" props. If you're using more powerful motors/props, start by turning down Rate Roll P in 25% steps.
While some testers have reported very good flights with the default PIDs, some have reported that this release is a little "sharper" due to the DCM improvements and have found they needed to:
reduce stabilize P by 10% (i.e. 4.5 -> 4.2)
reduce stabilize D by 30% (i.e. 0.15 -> 0.10)
increase rate D from 0 to 0.001
Tuning loiter can be tricky. Refer to the discussions which will appear below for more community feedback on what parameters work best.
Please post your feedback in this discussion. For enhancement requests and bug report, please add them to the arducopter issues list. When possible please include logs (tlog and/or dataflash) and tell us whether you're using APM1 or APM2 and what version of the software you're using (presumably 2.5 but tell us anyway!).
Thanks for this release go to the developers (both in the core team but also those who have provided bug fixes through the issues list) and also the community members who participated in the previous release thread and provided some great detailed information in the form of issue reports and logs which allowed us to nail some bugs!
I noticed I nicked on of the wires as they come out of the motor from one of my many crashes, a very slight tear in the heat-shrink where the motor winding is soldered to the wire as it compressed between mother earth and the quad's arm.
Left alone, this would have intermittently shorted against the frame.
Might you have the same thing? Could it be a short where your motor wires are soldered to the ESC wires and a spike of solder is poking through the heat-shrink and shorting them out?
Is it quad of hex? definitely seems like a hardware problem Mike
ive looked over the wiring pretty close and dont see anything like that but thanks.
it is a quad, i think i agree with you.
I am new to DIY drone and need some advise.
Thanks to all dev , I have been able to fly stab mode with this version 2.5.3.
My config is a quad :
Frame :Black crow (Epoxy 46cm motor to motor)
Motors:Dualsky 2826CA-18 980 rpm/V
Spectrum DX8 & AR6210
I am having the following problems
In stab mode the copter will shift always on theright side even after multiple calibation in MP or field éàsec Yaw left ( I can correct this triming on the reverse side then field calibration) power off /on with trim to zero) which is almost ok in stab mode but when switching to Alt hold or loiter the copter goes badly on the left side.
Here log & parameters
Thanks for any good suggestion
Calibration on APM2 . help needed
I did not get much help on my previous post, anyway now Altitude hold and loiter work very well.
The remaining problem is a strong drift on the right side and forward in stabilize mode even after calibration either in MP or in the field (Yaw left 20 secs.) with a level.
Is it possible to overcome this problem with a better setting of parameters ??
How is your APM 2 mounted? v2.5+ has changed up the DCM to better handle vibration induced noise, but some vibe isolation is still recommended. Is your APM 2 isolated well? You can enable raw data on the log file and see what your accels are doing during flight. When I was noisy, there would be +/- 3-5 gs on x,y,z. I was amazed it even flew!
My APM2 is suspended on the 4 corners with rubbers as recommended in several posts , props are balanced ,I now how and where to get log. files in the CLI MP.How do you enable raw data ?
Tomorrow ,I will look today's flight data.
You can go into the CLI menu, setup, logging, and "enable raw" .
I have mine suspended as well with no issues as you describe. The drift issue for me was pretty much solved with the v2.5 and the suspension. It still drifts slightly from time to time, but I blame that on a frame that has seen one two many crashes.
Have you checked for any bent motors shafts or mounts?
I have not been able to look at the accel because I could't dowload log files because they are all tlog or rlog. I will see if there is a post on that or re-read the wiki.
I don't think that the problem is coming from vibration ,it would also pertubes the loiter which is not the case and I have also tried on an other frame with the same leaning problem on the right side and forward.
In fact this morning , after a field calibration I flew for 2 to 3 mn without drift then it started again (No wind)
Altitude hold and loiter work ok altitude within +- 50 cm loiter within a radius of 2 meters.
Below the parameters file:
Im in two minds about mounting on rubber rings and particularly if it allows the board to wobble even ever so slightly . Any movement at all of the board relative to the crafts frame I suspect will cause oscillation and probably jitters during quick maneuvers. . I'm more in favor of adding vibration dampening pads to the arms and frame rather than suspending the AMP board. Take for example if the motors are causing a horizontal circular vibration from the motors and this circular rotation is say clockwise, then this is without doubt is going to affect the yaw if the board is moving differently to the frames yaw. So if anything I feel the oring idea is in some cases more counter productive than what its trying to achieve. The APM board in my view must be rock solid fixed to the frame to be able to quickly and accurately read what the aircraft is doing. Any compromise even if only very minute will without doubt affect the stability of the aircraft. We have to realise that if the board can be so easily affected from such small amounts of vibration and it is so sensitive, then the idea of APM board suspension mounts possibly is not a good idea
I feel some of the people having trouble with the PID tuning could be because their boards are moving and are not firmly fixed the the frames.
One method I have used to dampen vibration is to wrap a metal rod in some soft rubber and then slid this into the arm tube just under the motor. The rod floating in the rubber wrap takes quite a bit of the high frequency vibration out of the arms.
Just my thought on this.
One particular issue I read on the forum that made me aware of this was the altitude bouncing problem some people had. When I read that post I was wondering if the board was on rubbers and if it was also bouncing up and down relative to the aircraft frame. If it is then it seems obvious to me the reaction would then cause bouncy flight in quick accents and descents at least. I think trying to tune that out using the PIDs would be nearly impossible