I am working on dynamic notch flter configuration. For that I need the following two values,
hover motor frequency hover_freq and thrust value hover_thrust
I got the hover_trust value but not the hover_freq value.
Please let me know where I can find the value of hover_freq.
It’s the value for the largest peak that you read off the FFT graph
There are two graphs.
- FFT ACCO
- FFT GYRO
Out these which one should be consider for a higher value?
Please see the picture and point out the value.
The gyro graph, although often the peaks are at the same frequency
Hover_freq is 96.98. Is this wright?
hover_thrust is nothing but MOT_THST_HOVER. Am I wright?
yes, 100Hz is the correct frequency. You want the frequency (x-axis) not the amplitude (y-axis)
yes, MOT_THST_HOVER if MOT_THST_LEARN is set to 2.
This is clearly explained in the documentation. Did you read the documentation?
You mean I have to take the X- axis value only to update the following configuration write?
Harmonic Notch Configuration for Throttle Based Mode
- Set INS_HNTCH_ENABLE = 1 to enable the harmonic notch
- Set INS_HNTCH_REF = hover_thrust to set the harmonic notch reference value
- Set INS_HNTCH_FREQ = hover_freq to set the harmonic notch reference frequency
- Set INS_HNTCH_BW = hover_freq / 2 to set the harmonic notch bandwidth
I read it. My question is
hover_thrust and [MOT_THST_HOVER] are the same parameter or different one?
tell me where you see this so precise value
Hover_freq is 96.98 "
I am also a beginner and I have a lot to learn
From this graph. FFT GYRO Amplittude value.
Not the amplitude value!!! The Frequency (Hz) of the maximum amplitude value!
Yes, hover_thrust is equal to [MOT_THST_HOVER] if [MOT_THRST_LEARN] = 2
Open Log , from mission planner then go CTUN section, ThH (throttle hovering value) you can find over there, and ThO (throttle output) also.
In my log am not getting that CTUN section. Buy anyway I got the hover thrust from full parameters list.
CTUN might not be enabled in the parameter LOG_BITMASK
You can calculate the bitmask to enable it in full parameter list but I find it easier to use the checkboxes in the normal/advanced parameters tabs
Thanks for the response.I will check that.
So the hover_freq is 440hz corect? From the below picture.
No!!! That is the Accelerometer (FFT ACC0 graph) max amplitude.
You want the gyro (FFT GYR0 graph) frequency (HZ) at gyro max amplitude. And that is around 100Hz, the corresponding amplitude also happens to be 100, but that is just a coincidence!
So you don’t understand an FFT graph plotting frequency on the X-axis vs amplitude on the Y and only the Gyro graph is relevant. No big deal. Set the frequency to 100hz, the Band width to 50Hz and the Reference = Mot_thst_hover.