What is the most quiet motor(s)

Hi there,

I was going through topis for some time now and can't find the answer to subj. Here's my background: recently I started to consider making a motion sim for fun and fun. Due to kids/family I can play only late evenings/nights. Hence the requirement. If the rig will end up being too noisy I'll have to dismantle it (c'est la vie). So I'd better come up with something decent from the beginning.
The plan is to start with 2dof. If the process and the result will be fun enough I can add a gseat to it. Me + seat is roughly 90-100kg (an estimate). Games are flight sims only (elite, msfs). Another part of the plan is to get a VR some time along the way, so long throw on the motion sim won't be needed.

I've seen number of yt videos, but almost always there's a game sound so isn't clear how loud is the motion sim itself.

What would be the best option for motors, most quite ones? Say, in 200-500$ price range for both. I'm not after the cheapest option, but prefer to spend less, obviously. Of course I'll dampen it further afterwards with some sort of curtain, but the less noise I'll have to dampen, the better.
I I've read that most noisy are actuators and winch motors, so they are out of the question. What about others?

Also, from 3d printing background, I know that drivers affect amount noise a lot, to say the least. What would be the the most silent option here?

When you are looking for quite + powerful + affordable motors, my recommendation is second hand wheelchair motors. I don't know the situation in other countries, but in Germany you get a pair of them for 150-300 € on ebay. Of course you need some other components as well, like a motor driver (I recommend a Sabertooth 2x32), hall effect pots etc. which add to the overall costs.

Hi Markus,

Yes, I'm aware about cost of other components (more less) after reading the forum. Only the cost of motors was unclear as it varies a lot.

I've found on ebay some. So roughly speaking I should be fine with approx 200W each motor, circa 3700RPM, 24V, right? I'm going to mount them at knee, to keep the whole thing compact.
AFAIU 3700RPM is before the gearbox, what would be rpm after it? I've found one which says 116 rpm on sticker, but others don't. I guess that wheelchair motors will have same rpm, approximately , because of the designed speed of the wheelchair itself. Is this reasonable to expect?

For example: 200W https://www.ebay.co.uk/itm/114540779477?hash=item1aab2997d5:g:yi0AAOSwNDVfvoyZ
Another one: 450W https://www.ebay.co.uk/itm/324482181691?hash=item4b8ca52a3b:g:2CEAAOSwatdgJDXU

Would it make sense to use 450W ones? Or it'll be an overkill? I see most people end up in 180W-250W range.

Also, the first one has much bigger gearbox, despite having less power. Would it make sense to go after it, expecting it to be more durable,or for this application (motion sim) wheelchair's gearboxes are already way too strong?

In my opinion 450W are not an overkill, especially for a compact design.
For me, one of the most frustrating things when building my simulators have been weak motors.
Just look for a left and right motor of the same type for your 2DOF rig.

Edit: However, 200W could also be enough. In fact, I don't know the power of my own motors.

Another thing: Some wheelchair motors have a kind of flange, which can facilitate mounting the levers.
See this one as an example: https://www.ebay.co.uk/itm/133167361565?hash=item1f0164ae1d:g:kWgAAOSwHOVdd~fT

Looks like this one fits well - 450w, has a flange, and in the price range.
https://www.ebay.co.uk/itm/265140708430?hash=item3dbb9e244e:g:G7MAAOSwAu1giWqs

Re Sabertooth 2x32: one driver should be fine, right? it outputs 16A/motor with peak 32A/motor, and this ^ one requires 18A. AFAIU this 18A won't be continuous.

I've read elsewhere that a battery might be needed to handle recharge current. How to check whether it's needed in this case?

Yes, this motor looks ok. Do they also offer a second one? Wheelchair motors can be designed to differently that you really should look for a left and a right one of the same type.

About the Sabertooth: You don‘r need a battery, but you should add resistors for handling the reverse current. Somewhere in this forum you will find a wiring diagram, and the Dimension Engineering homepage provides a resistor calculator.

There are number of listings which sell a pair. I've noticed that some listings for the same wheelchair model left and right motors have very different labels and they aren't looking compatible. So I'll be buying a pair, just in case. I costs a bit more, 300-350£ for a pair vs 200£-270£ if bought separately, but it looks safer.

Thanks for your help, Markus! I appreciate it. I think I've figured out all components , will start collecting them and start the build probably somewhere in autumn, after summer trips and vacations (would they happen).

Wheelchair motors are quiet in my experience

Yes, I remembered that - on streets/shops you don't hear them coming. In a quiet room they won't be as silent, but not loud as a winch either.

Tip, its not the motor that makes the noise, its the gearbox...

In my rig, the noisiest components are the five cooling fans (one inside each power supply unit and one mounted on top of each Sabertooth board). And some cracking sounds of the mechanics on fast movements.
As an audio sample you can listen to the video at the end of the first post of my build thread.

Yes, fans are noisy, but can be replaced with quite ones and put in a soundproof-ish case along with PSU/drivers. Also their noise is monotonous, so kinda doesn't disturb much over time. Mechanical clicks are harder to hide. Will see how it'll work in my case. Also I plan to use plywood frame, which could end up squeaking. Probably I'll use some thick curtain around machinery under chair. Will see.