AC 3.2.1 Sudden Throttle increase in Land Mode

ArduCopter Copter 3.2
1

Today I’ve tried to fly my quad-copter loaded with AC3.2.1 code by arduino.
Situation here was:

  1. Armed the motor in stablize mode
  2. Increase throttle to take off and hover around 1meter above ground
  3. Changed to Alt_Hold to test the throttle reaction, “It is increasing height even though my stick is at 50%”
  4. Changed to Land Mode with Land Speed set at 35cm/s

While the quad-copter was slowing down and decending to ground, i moved my yaw stick left and right and then suddenly the motor increase its speed as it max throttle was there. "This was during Land mode, which Throttle stick should not affect the motor.

I took of the props and re-tested my situation, but this time round the motor did not increase speed while in landing mode. So I could not find out whats the issue I’m facing

2

Too much vibrations.

3

Erm, too much vibration from? and to?

4

from your propellers/motors
to - Zaxis in accelerometer.
Read up on vibrations, and fix them + check your log vs documentation.

5

alright! roger Andre, thanks for your help! Will look more into this

6

Hi I have check read this http://copter.ardupilot.com/wiki/ac_measuringvibration/ about the vibration and checking my logs, but the diagrams are all the previous version

May I ask which should i tick for the ACCX, ACCY, & ACCZ shown from the webpage?

Is it AX, AY, AZ from the image below?
http://i298.photobucket.com/albums/mm247/Tuck3rz/Untitled1.png

In order to see my Throttle_In and Throttle_Out data, Do i look at Chl3_In and Chl3_Out respectively?
Apology for such basic question

Thanks and with regards,
Zhen Liang

7

I’m not able to view the ACC_Z (Acc_Cal_z) plot accurately from telemetry logs. I don’t know why, The graph i got was just a pure straight line which is without any vibration and it seems pretty impossible to me…

http://i298.photobucket.com/albums/mm247/Tuck3rz/Untitled2.png

8

Try to download dataflash log - You have to set your LOG MASK to default + imu , then vibrations will be logged

9

Hi there, i have disabled dataflash logs in my AC3.2.1 code as if I enable it, my apm cannot connect to mission planner.

Nevertheless I will reflash the firmware from mission planner instead to check the logs then return back to the codes

10

This is the logs which i obtain
http://i298.photobucket.com/albums/mm247/Tuck3rz/Logs.png

as observed all my accelerometers measurement of vibration is totally unacceptable. Therefore i guess I have to work on my vibration damping.
However my ACC_Z values have a sharp spike of almost -60, what are the reasons that might cause this sharp spike?