Today, I attempted to fly the VTOL in guide mode. However, after about 40 seconds, the throttle of pusher motor seemed to stop, and the lifting motors continued to spin because it reached Q_assist_speed. When I used the gimbal to check, neither the pusher propeller nor the motor were operating. The aircraft eventually crashed after the battery was depleted. Unfortunately, I didn’t capture the screen at the time, so everyone suspects I’m lying and that I didn’t properly secure the pusher propeller before flight, which led to it falling off during flight. I am certain that I used the gimbal and saw that the motor and propeller were not functioning at that moment. Can anyone offer me advice? A TLOG file is attached for reference.
Hi @naphuc179
first of all welcome to the forum.
Do you have a log file on the SD card (*.bin). These *bin log files contain much more data than the TLOG files recorded on the ground. Please upload the *bin logfile
Secondly other people are only able to download from your google drive if they have a google account. I would change that for the log file.
Rolf
Hi Rolf,
Since the aircraft crashed into the sea, I was unable to recover the SD card to obtain the .bin files. I only have the TLOG file, which contains some information about the flight.
I have reposted the TLOG file to make it easier for everyone to download. Thank you.
Near
That’s really annoying
Getting something out of the TLOG files takes a lot of time. If I have more time tomorrow or the day after, I’ll take a closer look.
Thank you in advance for taking the time to look into it. I appreciate your help.
I think the propulsion failed completely, shortly before reaching the guidet target point.
Note ch3out (throttle) and the airspeed when replaying tlog in the mission planner. The airspeed will suddenly slow down even though you are at full throttle (ch3out 1645 µs corresponds to the maximum 70% throttle you have parameterised). Before the Q-motors start (at 16 m/s), the current consumption is remarkably low, so that an ESC may have broken, switched off or a cable may have come off. Ultimately it doesn’t matter, you had no chance of returning with the quad motors alone.
Yeah, can be seen here as well:
Pink is servo-out for one of the Q-motors, green is the plane prop, blue is current.
First phase we see Q-motors active, then second phase transition to plane with Q-motors disabled, then there is a short phase where plane motor goes to max but current drops to baseline, that’s where propulsion failed. Then Q-motors take over again.
Note: Green going to max does NOT mean that it spun at max. This is servo-out, meaning the FC commanding the ESC to go full throttle. Together with the zero current it means that there was no spinning at all.
If the propeller had come off, there would still have been current drawn. As Rolf said, this was a dead ESC, detatched cable, burned out motor, or anything else between power supply and motor.
Thank you very much for your detailed analysis and for taking the time to help me understand what happened. I really appreciate your support and the insights you’ve provided.
I am very grateful for the thorough explanations and the effort you all have put into analyzing the issue. Your help and time are greatly appreciated. Thank you!