The test site was very windy today so they could not tune the drone. They will try tomorrow. I agree with you, it has to be tuned as best as we can before flighing with terrain follow.
Here is a bin file from a flight today. Just to separte things out, we changed our algorythm for getting ground from the radar sensor, removed the filter. The lag is now gone. During straight flight you will see in the linked bin file that the dolphin oscillation seems to dampen out. Previously it did not. My conclusion is that removing the lag helped, and with tuning we should be able to get the rest sorted. We still need to better understand what parameters we need to use to tune.
The test was conducted in high wind conditions. At waypoints the rangefinder gets very noisy. One of the issues we deal with is to correct for pitch when we approach waypoints. We stream the pitch from the flight controller via the ATTITUDE parameter. We cannot get the interval period below about 150 ms. If we want to use the picth from the flight controller, then we need it at intervals not exceeding about 50 ms. What options do we have to speed it up to our companion computer? We only stream two parameters, GPS_RAW and ATTITUDE.
By the way, Copter-4.3.4-rc1 has some improvements to the filtering that may help as well.
In particular item 3k from the release notes linked above
- k) Surface tracking uses filtered and corrected rangefinder values
Thanks. This explains what we saw today that the rangefinder values are filtered in copter 4.3.3 but not so much in 4.1.0.
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The values are filtered in 4.3.4-rc1 and NOT filtered in 4.3.3 and bellow.
We have been able to tune out a lot of oscillation, but some still remain. Our latest log is here: 00000130.BIN
Are you sure that’s the correct log?
It shows as being earlier that recent once and is still Arducopter 4.3.0
Thank. We changed drones and missed checking that. We upgraded to 4.3.3 and here is the log: 00000132.BIN
We noticed that we are not reaching the desired altitude. Will be tweaking that.
No Battery voltage and current monitoring - that will be essential for safety and even for tuning
ARMING_CHECK,1
INS_ACCEL_FILTER,10
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
After you’ve set up the battery monitor and at least got voltage readings, connect to MissionPlanner Initial Parameters and put in your prop size and battery cell count, select Suggested settings too, then accept everything it offers.
Then just do some hovering and gentle movements in AltHold and Loiter.
Let’s see that log.
I’m still a firm believer in getting the tuning right first, so you know the copter works as it should at a basic level - then move on to advanced features and any fault-finding.
If you dont have a good tune to begin with you wont be able to tell where issues are coming from or how much of a problem they really are.
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