Copter repeated gets potential thrust loss during loiter and auto missions

ArduCopter
1

Hello all,

I have been trying to fly some autonomous missions with my quadcopter (f450 frame) and I have repeatedly been getting a potential thrust loss(1) and potential thrust loss(2) errors that cause the copter to land very hard. These occur during loiter and auto modes and I am curious to know if you guys have any suggestions. The loiter mode works perfectly for around 30-40 seconds and then suddenly the copter starts swaying (pitch and roll both at times), drops altitude, and becomes impossible to control.

I am using a Pixhawk 6C flight controller with a raspberry Pi onboard to take pictures and run a python script to log the position of the drone. The motors are the ReadytoSky 920kV 2212 brushless DC motors from amazon (link) with 1045 propellers (link), the frame is also from amazon (link), and I am using 35A FlyColor Raptor 5 ESCs. The compass and GPS I am using for the drone is from here. I was having issues using both compasses from the GPS and the Pixhawk, so I have been solely using the compass from the aforementioned GPS. The batteries that I am using are both 5200mAH with one having 35C and one at 50C. I have encountered the thrust issue using both of these. The total weight of the drone is 1459 grams.

I would like any suggestions to improve the performance of my drone, or if there are any glaring issues in my setup, please let me know. My initial thought is that the drone is too heavy for the motors/the motors aren’t powerful enough to hold this much weight for an extended period of time. If this is the case, can you suggest alternatives? I am very new to building and flying drones so any additional information or tips is greatly appreciated.

Thanks in advance!

2

Have you tuned your drone properly? How to methodically configure and tune any ArduCopter & GitHub - ArduPilot/MethodicConfigurator: A clear ArduPilot configuration sequence

We’ll need a flight log for any attempt at diagnosis.

2 Likes
3

These are great! This is the first time I am seeing either of these links so I will definitely check them out. I had only gone through the Ardupilot Copter documentation and first flight checklist before flying.

4

I was having issues uploading the bin file to this thread but here is a google drive link to the most recent flight log where I had a thrust loss during an auto mode run: 2024-07-02 12-20-02.bin - Google Drive.

5

Those links won’t do you any good with an overweight/underpowered craft. Average outputs are too high and under demand they are maxed out hence the thrust loss error. No battery logging either. And you are on old firmware.

RCout
RCout3354×1053 242 KB

2 Likes
6

Hi Dave, thanks for your info! Do you have any suggestions on motor sizing to help lessen the load on the motors? As far as kV, I read that 900-1000 is a good range for 450mm drones (feel free to correct me), but in terms of the size of the motor, what would you recommend for an ~1500g drone? Are there any good brands that you recommend?

I will try and get the battery monitor to work. I had tried in the past and it would not display anything (just zeros), but maybe after updating the firmware it will work. Thanks again!

7

Buy a subscription to eCalc and select components that work. You want the linear hover thrust value to be 50% or less.

1 Like
8

I’ll take a look at that, thank you!

9

Don’t buy any of this junk:
Hardware to avoid

2 Likes