Esc telemetry notches?

Im having vibration around 45hz but i cannot place a esc telemetry notch below 120hz. Im only able to use a fixed notch which works. Im just wondering why i cant use a bidirectional dshot based notch below 120hz

My basic gyro filter is 40z

This is all using the web filter tool
Fc is heewing fx-405

The ESC telemetry targets the filters based on the RPM of the motors, I’m assuming the 120hz. The 45hz spike you’re seeing would be some kind of airframe, or aerodynamic vibration from the airflow in VTOL mode. A static filter will be a good choice. You could see if a throttle based filter will work there too.

That makes sense. Its 2 spikes close to each other. I think its just the tilt servo mounting vibration. With a fixed notch do i use the highest frequency. It changes flight to flight. Sometimes its 42hz other’s its 45 hz. Is there a way to cover both. Does INS_HNTC2_FM_RAT work with fixed notches?

I’m on the fence here. I don’t think so. But you could play with the bandwidth of the filter to see if that covers it. Might be worth using the webtool over a few logs and see what averages out the best.

It only varies between 42-51 hz. Would 25 bandwidth cover it? It only happening around 3k rpm not at hover. Since im not moving the throttle around besides to take off. Am i just over thinking it. Also how much cpu usuage is ok? Im around 40-50% with 1 fixed and 1 harmonic and 1 esc telem with 1 harmonic. I choose multi on them both.

Use the estimated post filter results on the web tool to find a filter setting that works. It’s a narrow enough band that you should be able to use a fairly narrow fixed notch.

Looks like 45 freq and 30 BW covers it. It also looks like after 3k rpm the esc telemtry notches remove all the noise to below -90 db from 5k rpm up.

You don’t need multi on the fixed notch. and probably don’t need the harmonic on that either. Hard to say without a log. But generally, try to turn off as much as possible.

Im going to soft mount my fc. Its only foam taped on top a pdb. Which is is probably getting the Vibration from the carbon spars. They directly attach to the tilt rotor motor

Without the 2nd harmonic i get a 20 db increase in noise around that area . Graph is pre and post not estimated

One of those mounts with the rubber isolation balls.

What are the vibration values now?

Those isolation mounts are often counterproductive, especially on a small, maneuverable craft.

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Whats pictured. I havent used the mount. I just bought it.

This is a heewing t2 vtol. So i dont expect much

No. Not the FFT transform, but the raw VIBE values.

How do i check that? Its much better than before. Wings vibrating and the tilt servos were shaking. Log was full hence the yaapu beeping. It was also windy around 10 to 12 mph

Putting those big squishy mounts on that probably will just make it behave worse due to poor coupling between actual attitude and the board itself.

I’m assuming the higher vibration portion of the flight is before transition. It’s slightly high but not out of control. Secure all loose wires and tighten anything loose on the frame. Do that before resorting to softer mounting.

Ok. I will do that. Can you tell me how i use this graph to set my feedforward. I have it at .15

This is my cable management. Anything stick out as problematic?

Those long stretches of unsecured wire are potentially problematic.

It’s all here:
https://ardupilot.org/plane/docs/tilt-vectored-yaw-tuning.html

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