SimFeedback-AC DIY Motion Simulator 10Khz Research

[scornflake]

Hey all,

I'm really keen to build one of the SFX-100 rigs, but I've heard (been in the presence of) my brothers and the 10khz servo/driver noise really does my head in, so much so that I would not be able to put up with it. 5-10m of it, and I'm done. This is a darn shame

So, I'm going to see if I can get rid of it. Either electronically (preferred) or with accoustic treatment(s).

In this thread I'm simply going to document my journey. At this point I am unsure if it'll come to anything. Maybe I won't succeed. Maybe I'll get half way. Who knows.

The story begins with Neil buying himself a single driver and servo, a 3d printer, and saying to himself "hmm. what next"

My full notes are here, but I can't promise you'll understand them: https://docs.google.com/document/d/1J4AUnKNYtFRujTR9BFBB_lJudZRP_02BOt6lfAIN45I/edit?usp=sharing

Look below, I'm going to try to post a more understandable version of my journey!

 

[DotComRich]

Its the driver box that powers the actuators, you can get either mdbox where one box can power 4 actuators, or aasd where you need one box per actuator. There is a setting for mdbox where you can raise the pwm frequency from 10khz up to 15khz or higher to the point where humans can no longer hear that high frequency of sound.

On my mdbox they were set to 10khz, changing this setting to 15khz immediately stopped the high pitch whine

 

[Neilwales]

I see great thanks for that info

 

[mrbean_phillip]

Someone mentioned the Argon drives before. I have used those extensively in OSW Dd wheel builds, they are really good quality units and easy to configure via Granity GUI. Also, having had from small to large Mige servos on them, I cannot recall any high-pitched wine from the drive. Nor would I, as it drives a 380VDC pwm output....not AC, where, if I understand Thanos’ feedback correct, is where the high-pitch noise develops, switching from single phase AC to 3-phase AC...

I am planning to perhaps use them on my Motion sim build, I still have 3 or 4 here on the shelf. Need another 1 for the traction-loss actuator, but I can pick that up when I meet with Tero at Granite Devices in Finland again end of February.

I will be using Thanos’ controller, I might ask Tero into looking at adding capability to handle ‘Treach’ from Thanos’ controller, I have not looked that deeply into it yet, but will chat to him as to what might be required.

Will keep you guys posted on this, as mentioned, they are very good quality, if a bit pricy...

Cheers,
‘Beano

 

[Amtk1251]

I think I got through the thread. Maybe I missed it, maybe I didn’t-

does running it on 110v conclusively help? It’s annoying when the room is completely silent. I still have to mount the servos to my rig. We will see when I actually have my VR fired up.

 

[scornflake]

I've just done my 1st rig setup/test today, and the combined noise of drivers + motors is "something to behold" in a baaaaaaad way. Glad I've at least got my driver enclosure on the way to being done and that I've already started a design to the motors (btw: I intend to release it all for free in case anyone wants to do similar).

It does make me wonder if I should ditch the AASD stuff for mdbox (which can do 15khz, which I know I cant hear). Anyways. I'm going to persist and finish what I started; THEN I'll consider other options. I'm curious to see how much better I can make it using accoustic blocking.

I intend to make some sound measurements of the rig as it is now, which is totally open. i.e: darn noisy. I'll use the same equipment as I did for my initial sound tests in this post. I'm curious to see just how freaking bleeding near to 0db the 10khz is when it's 4 drivers and 4 motors; all mounted. I reckon it'll be over 0. It's DARN loud. Horrible.

Yay! Such a positive message from me
Oh wait. Opps. Sarcasm: disabled.

 

[scornflake]

Here's what I've got for a test setup so far:

Vid prob says more than pics would

 

[Amtk1251]

Here's what I've got for a test setup so far:

Vid prob says more than pics would

Let me know how the 3d print goes!

 

[hazardpro]

Quick question

when testing for the noise is it all the time it’s powered on or just when the motors are moving?

turned my controllers on today and can’t here any wining (but motors are not connected).

just wondered

 

[Furnace Inferno]

Quick question

when testing for the noise is it all the time it’s powered on or just when the motors are moving?

turned my controllers on today and can’t here any wining (but motors are not connected).

just wondered

Just when a profile is active aka the motors are active. If the controllers are on but no profile is active so the motors aren’t on lifting the rig then it’s completely silent.

 

[hazardpro]

Has anyone tried changing the cables to shielded and then tested the noise??

 

[hazardpro]

Also the MDbox (one to drive all four), is it plug and play, eg you can just change it over? Do we know what settings are required to run the motors on the MDbox?

ps and just to clarify we are saying buy 4 of these and have no wining noise?

This product is no longer available.

This product is no longer available.

m.alibaba.com

 

[Tronicgr_6DOF]

Also the MDbox (one to drive all four), is it plug and play, eg you can just change it over? Do we know what settings are required to run the motors on the MDbox?

ps and just to clarify we are saying buy 4 of these and have no wining noise?

This product is no longer available.

This product is no longer available.

m.alibaba.com

The unit described on the link and the price is for a Syntron HS drive (single servo), not an MDBOX 3in1 unit... the MDBOX 3in1 costs about 900usd, and the MDBOX 4in1 cost about 1200usd!!! And you need to get matched servomotor along with it, cannot just connect a 90-ST motor to it...

Also the MDBOX unit is not compatible with AMC-AASD15A! I used special controllers for it the previous years with DACs to control them, see on this video a MDBOX 3in1 unit being controlled by my AMC-NANO controller (small gray plug):

 

[DotComRich]

Quick question

when testing for the noise is it all the time it’s powered on or just when the motors are moving?

turned my controllers on today and can’t here any wining (but motors are not connected).

just wondered

For me on mdbox the noise was constant no matter if it was idle or actively racing receiving telemetry.

 

[Tronicgr_6DOF]

For me on mdbox the noise was constant no matter if it was idle or actively racing receiving telemetry.

MDBOX is always active after power on. The only time it will be silent is if you press the e-stop switch...

 

[hazardpro]

I thought the MDBox = no noise?

 

[Tronicgr_6DOF]

I thought the MDBox = no noise?

You can set PWM frequency of MDBOX at 15khz, which is near the audible spectrum. But you know these are on still, the same way you knew an old cathode TV was on when you were entering the room...

 

[DotComRich]

I thought the MDBox = no noise?

Correct, thats why I said "was" as I no longer have the noise

 

[Mascot]

I've just done my 1st rig setup/test today, and the combined noise of drivers + motors is "something to behold" in a baaaaaaad way. Glad I've at least got my driver enclosure on the way to being done and that I've already started a design to the motors (btw: I intend to release it all for free in case anyone wants to do similar).

It does make me wonder if I should ditch the AASD stuff for mdbox (which can do 15khz, which I know I cant hear). Anyways. I'm going to persist and finish what I started; THEN I'll consider other options. I'm curious to see how much better I can make it using accoustic blocking.

I intend to make some sound measurements of the rig as it is now, which is totally open. i.e: darn noisy. I'll use the same equipment as I did for my initial sound tests in this post. I'm curious to see just how freaking bleeding near to 0db the 10khz is when it's 4 drivers and 4 motors; all mounted. I reckon it'll be over 0. It's DARN loud. Horrible.

Yay! Such a positive message from me
Oh wait. Opps. Sarcasm: disabled.

Horrible, isn't it?
At least there's a general acceptance now that the problem is real for certain people. When I first highlighted the issue around a year ago there were lots of patronising comments from non-sufferers saying that I was complaining about nothing, just because their hearing wasn't sensitive to the 10kHz whine. It's a shame it's an issue for some of us but in a completely selfish way, I'm kind of glad I'm not alone.

 

[Dennis Karlsson]

I built my SFX-100 in January 2019. I thought I could learn to ignore the whine but it's getting more and more irritating. I can't stand the sound. Something has to be done to fix this.

 

[Furnace Inferno]

I know people are looking at covering the motors but why not something smaller/simpler/cheaper and just have something which absorbs the frequency over the ears.

As I said previously the headphones I use I just need to put them on and I can’t hear the whine anymore and they are not noise cancelling or closed so I can still hear everything outside it’s just the foam earcups absorbs the whine completely.