Thanks! It’s an Ag drone, flies low and slow while spraying and only flies in good weather. Also it’s constantly loosing weight as it sprays.
I’m not sure how to get rid of the yaw bias, I have verified all 4 motors are vertical. Would a autotune in yaw be helpful? I appreciate the assistance, really helpful.
I looked at the RCOUT in your latest log, motors 1 and 2 are lower on average than 3 and 4. If you have the std x frame, motors 1 and 2 are your right front and left rear. These motors 1 and 2 spin counter clockwise and if they were brought up to the same speed as 3 and 4 it would turn clockwise (to its right). To adjust for this, the autopilot is lowering motors 1 and 2 and raising 3 and 4. So you want to check all the motors for some degree of making it want to turn to the right (clockwise). It might be 1 motor, it might be a combination of miniscule angles on several motors, or I even have thought that motors pointed straight might put out angled thrust (stand in front of a fan, ac, or forced air heater, the airflow comes out at an angle! tho on a MR the 4 motors should balance out). If they are all truly straight up and down, try a tiny bit of an angle and refly, then check RCOUT c1 c2 c3 and c4 and hopepfully the motors are all about the same. Or like with mine, the back 2 motors (2 and 4) are elevated if I’m fighting head wind but trying to stay in one spot if you get the idea…
An Auto Tune would do nothing for the Yaw bias. It could also be the props are inconsistent. The problem you can have here is even unloaded your thrust/weight is low and it’s compounded by the yaw bias. It’s entirely possible one or both of those motors will reach max command which compromise’s stability and generate a Thrust Loss error. Lot’s of crash’s have resulted from this.
I tried to rebalance the motors again and align them all. Here is the file from my last flight. Thanks
File name: “2021-07-31 15-38-21.bin 31 July with Proximity avoidance on.”
https://drive.google.com/drive/folders/12scDkGkk4NdqlhPVFec8WNyRYSdzVeqG
Looks about the same. You might have to do a number of cycles where you fly it, look at the log, figure out which way its wanting to yaw, adjust the motor(s) tilt, then repeat.
Does it make sense what you’re looking for in the logs? Ardupilot when it wants to yaw, raises 2 motors and lowers the other 2, utilizing the natural rotation that the elevated motors give. But yours has some sort of tilt to the motors that make it want to yaw to the right. So its having to use left yaw (motors 3/4 elevated) to compensate. You want all the motor outputs (RCOU c1…c4) to be about the same or fairly close. Especially with how its a little underpowered, there isn’t much more motor 3 and 4 can do for maneuvering, as your closing in on the upper end of the throttle.
Use a tank with internal slosh baffles.
No change really and it’s still a craft that needs a weight loss diet or more power at that weight.
22 days and counting and that metric hasn’t changed… I think by now you can troubleshoot the thrust/weight issue by graphing the RCouts. Perhaps come back when that issue has been resolved.