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!
How I must programm the 3DR 20A ESCs with the original 850KV motors an APM2??
Cut Off mode??
I would leave all on default except timing. Default timing is low (according to documentation with ESC's) - make it medium.Improved stability for me.
Other defaults are:
Battery type default is LiPO (I assume you're using LiPO? )
Cutoff is Soft
Cutoff Threshold is medium as far as I remember. You could make this high for maximum battery protection I suppose.
Configuration used by me in my octoquad, 8x850kv turnigy 10 apm bat lipo 2650 10x4.5
battery: nixx. increases the flight duration of the battery, drop. alarm. visual and auditory
cutoff type. soft cut
cut off volt: low
start mode: normal
govermor mode: off
Words taken from rc grup. http://www.rcgroups.com/forums/showthread.php?t=1097355
applies to practically all multicopter with programmable esc.
For multicopter use and good performance the standard ESC's must have a manually configurable throttle range calibration for the best performance. Do not use ESCs that have "auto-throttle calibration". They will not work well on multicopters and will cause excessive drift, uneven motor startups and unequal power.
Set the standard ESCs for brake and governor mode off, LVC off if available, start = normal, soft cut-off, NiMh, low voltage. *Yes you did read it correctly Set NiMh even though we use lipos! Reason: http://www.rcgroups.com/forums/showp...postcount=1411 andhttp://www.rcgroups.com/forums/showp...8&postcount=32).The caution to keep in mind even when you set NiMh is that it does a voltage test when you first power on, so you must always use a full lipo or it can still cutoff if it drops below the calculated percentage of power on voltage. The best practice is to use the FCB's built-in alarm if it has one or separate lipo balance charge connector type alarm and then set your Tx to alarm two minutes before the lipo alarm sounds that you can carefully find out during a low hover battery flight test. The reason is you want to have at least enough reserve power for a safe landing. It takes a lot of power to arrest a descent, especially if you have a heavy model. When a lipo alarm sounds it can sometimes mean "land now!". Older and weaker lipos should be retired early from being used in expensive multicopter builds. For motor timing, you won't notice a huge difference between low, medium and high timing as this setting is for motor efficiency. If your motors stutter when starting or click excessively, and the motor timing is set to high, then drop it to medium or low. Most leave it on medium timing with good results. A few ESCs have another setting called PWM Frequency such as the AEO ESCs, Mystery Blue and Red Series and YGE ESCs that can be set to 16khz vs.the typical 8Khz. The 16Khz setting on ESC's will eliminate the ringing that annoys most Gents at the 8Khz setting. Be absolutely sure to do the ESC throttle calibration. The ESC throttle calibration is very important for the best stable multicopter performance. ESCs that have auto throttle calibration are not suitable for multicopters. For good performance in multicopter use, the choice of standard off-the-shelf ESCs must have the feature of manual throttle calibration. This only needs to be done once during the initial setup. This is usually accomplished by connecting each ESC to an Rx channel 3 throttle and then powering the ESC with motors attached and props off, then powering the Tx with the throttle stick full up, wait for a beep, then throttle stick full down.
very useful post as usual,thanks Norman...
what is diference btw. timing low,medium,high...my turnigy plush is on high should i change this?
Low end punch comes from mechanical timing and the over-rev comes from timing boost/advance in the esc. adding timing is basically increasing the kv of the motor .. higher kv gives ya the rpm's and lower kv gives ya torque. ... boost/advance helps most on motors in the 17.5 range and as the turns go down the boost/advance has less effect exept for creating heat .. best to just swap motors for a different kv rating that suits the track conditions better and regear the motor and propeller. changing the timing is equivalent to rotating the brusshes agle in a brushed motor.
I use low time. has given me good results, some-time use all depends on the tolerance of the esc and motor.
Important beginner NOTES on ESC set up : Read this before connecting any ESC !!
Norman thanks for such a detailed explanation it definately helps those of us new to electric flight.
These pictures show the configuration used by my
Turnigy Plush 10amp esc and 30amp. also the use in rctimersof 18amp, motor XAircraft 850kv, or rctimer 2830-14 850kv with accessories 10x4.5. the first I must stress that are very good with balance.I must emphasize that it is my configuration and it has worked well in all the models I have made. but not mean it is suitable for other models.
This is a standard of multicopteros.
Yesterday my hexacopter, APM2 and 2.5.5 finally were allowed to collaborate in their native element, Free Space!
I dared to take off and I could touch down on my local airfield.
Thanks for support