Showroom 6DOF Stewart AC Servo Motion Platform Build

Just thought I'd post some progress on this toy...

Connected the cables

Got the cabinet on the stud wall, its not really, just a bit of platerboard to hide the machinery behind.

Notice the emergency stop button (yep finally got it fitted and on on the seat platform)

Shortened all the cables (god what a job)


Made some of these beauts...





Even got some nice little caps to go on the gearbox shaft.

Made all the bits fit in a box and all pluggable.



Did a bit of testing with a lot of help from the @knaufinator and his video on setting the Simtools profile and got this...
https://wavepower.org.uk/20241208_Progress_Update.wmv
They won't let me upload a vid so you can get it yourself, should you so wish.
(and thats my site which I've had over ten years, just to store stuff, and transfer large file back and forth from work mainly)

Checked the fitting of two seats...then...


Surveyed this fantastic machine front top to bottom for a few hours...

Bloody fantastic.

So I've recently started work on this..


it needs to fix direcly onto my platform frame

Here's link to the 3D assembly file, which is an .stl file and windows seemed to find a 3D viewer to open based on it's file extension. https://wavpower.org.uk/Bell206_Cockpit_Assembly-2.stl

So I'm hoping to make the Bell206s' dash panel removable, and plug and play a car dash (and pedals)
The 3D exploration is to see what parts I can make with basic sheet metal tools (shrinker/stretchers/brake folder) , with the more complicated small bits resin printed

Something I forgot to mention in my previous post was that the 3D model is primarily a method to experiment and explore how the finished article may look if I made it from shapes I can actually manufacture.

I don't have the luxury of limitless funds, to get every part to look like the real thing, but I'd like to be happy with the finished product (up to a point anyway).

For instance, I fully expect the nose section to be shortened, as I'll never be able to get close enough to the screens, and to be honest the screens are already looking too small in relation to the cockpit.

Managed to get a bit more done on the cockpit model, but won't start cutting anything til I'm happy with dims & scale.
I'm using FreeCAD version 1.0 as it's open source and as the name suggests, it's free (nope not Free trial, or Free download, it's really free). I've been using it for a few years now, and watched it go from unbearable, to quite reasonable.




Here's the assembly file should anyone want a deco at it.
https://wavepower.org.uk/Bell206_Cockpit_Assembly-3.stl
(drags & drops nicely into Freecad)

Will be making a new set of pedals, as the ones I bought last year (SN-1)

are nothing like the Bell206 originals and don't lend itself to fitting in the required space very well. I will of course be using the sensing circuitry which I've taken out of them, and it will be placed in the centre console between the two sets of pedals.

I can see two cyclic sticks and two pedal pairs in your CAD drawings. Do you plan to couple them together? An instructor/student combination would be really interesting.

Yes, I do intend just that.
I found this on the internet,



which I figure is doable, and I have a Virpil joystick base.



I also have the Virpil collective, so I may have to copy the basic lever/throttle part (or buy it), then run the tube underneath the seats.





I'll add those bits to the CAD model as I progress.
For the pedals I'll put the SN-1 pedal sensor in the area between the two spans stretching for & aft.

Cant get on my PC tonight. But heres a few pic s I took to show the lads at work.





Getting closer to the point where I can start cutting.

I like the idea of putting the cyclic coupling mechanics under the seats. But is it intended that the joystick box in the middle sees the average of both inputs? The connecting bar made of sheet metal can't transfer any torque so the coupling is not stiff.

Also, the ball joints at the base of each stick can't handle torque which is produced by the handle at the top being off-center. So I fear it will rotate around the vertical axis instead of tilting to the left and right.

The handles are prevented from rotating by the rectangular bar between them, attached by clevises.
This effectively locks them together regards for and aft movements, and simultaneously for left and right movements.

Yes, should work but IMHO has a weak point:

The bearings at the connection to the bar have to transfer torque. Even a tiny amount of backlash or elasticity there will make the control feel floppy. And the connecting bar definitely has to be stronger than in the picture, e.g. a stiff tube instead of a stripe of sheet metal.

I'd do it that way:

It's like two U-joints but with the inner bearings removed and connected with a torque shaft. The shaft transfers the pitch movement while the pushrod takes the roll movement. This way the torque is transferred with a single solid part with no bearings or joints in between so no backlash and less flexing should occur.
The pushrod is connected with ball joints like in your design. It can also actuate the joystick box. But I'd make it straight and not bended.

I agree with Aerosmith's torque tube being necessary. I'll add that you should ditch the virpil and go with VPforce FFB diy motors & gearboxes, so the balance, feel & friction is fully customizable

Much better. But I'm still confused.Could it be that the curved stick is rotated somehow by 90°, @smitty ? I mean, the stick can't be moved in the roll direction. It would rotate around the vertical axis, instead.

haha! yes you are correct, my drawing was quick and dirty, just for the general idea, and i hoped you didnt notice
here's a better geometry

I've googled "VPforce" but haven't found much information. There's a page where you can register on a waiting list and a link to a Discord channel. But I'm a bit worried about pre-paying somebody who hasen't got a proper web site. I think somebody said you have to wait half a year or more to get the full FFB stick or yoke but if you only order the motor and driver board it's much faster. Can you give us a hint what exactly we'd need and how to order it? Is there a manual or data sheet of the specs and features?

@smitty ...Ditch Virpil!!! Ha ha yeah, maybe in my next life, the cyclic & collective owe me the best part of a grand, so it'll have to do for now.
I did have a look at VPforce (when browsing your pages), but they didn't make me feel safe enough to part with my money.

All comments and dwgs are valid & food for thought, I'll ponder over it for a week or so, then bash out the dimensions dwgs. I may substitute the rectangular bar for a tube as you've both drawn, but include some thrust races within the clevis assy. Still not sure yet, will have a rumage through my bearings box.

As a lifelong precision engineer I don't have any worries about getting rid of any 'play', and my biggest concern now is that friction needs to be precisely adjustable, and the joystick needs to be centrally balanced. At the moment I can see it will be front heavy and fall forward.

Oh, and this weekends job is to get the collective modeled and positioned.

Appreciate your feedback chaps

Yea, he doesnt have a web site but the discord is very active, and thats where you can find specs on the motors. You dont prepay until he's ready to ship to you. 800+ happy customers so far for the built unit and unknown numbers of diy kits. I have 3 diy kits for joystick pedals and collective. I also have contributed quite a bit to the telemetry software on github. You can download a manual here

I'll have to take another look at these...having feedback on the cyclic would be the cherry on the cake.
Thks @smitty

Cool, Im not sure what sim/heli you fly most, but if youre into the msfs H145/H160, check out this vid by another guy from the vp discord For other helis it does do trim release, and will give you shake feedback for ETL, VRS. And you can control the friction with a potentiometer. It'll also stiffen up good on hydraulic loss. I dont fly DCS, but if that's what youre in, those guys like it there too

Ah yes, and I've just found your notes about the precision gearboxes on Discord.
I think I'll buy a 1-axis kit and test it with my pedals. Later I can buy additional FFB kits for the cyclic and collective. They already have force trim with stepper motors but I'm not really happy with them. They get boiling hot and they don't have enough torque to counteract the spring forces at full deflection.

Do you know offhand what size(wattage) those motors are that get boiling hot?
I am thinking of getting a two axis kit for my cyclic, if all goes well, I can expand.

Ok, so I bit the bullet and ordered a pair of 86BLF04 - 86x94mm - 4.2Nm peak - 2.75kg - NEMA34 motors,so it's back to the dwg board, to concoct another system.

Worryingly that's adding over 5kgs to my cockpit weight.

I'm already wishing I'd ordered another one for my pedals, plus does the collective get much in the way of feedback?