Question Suggestions for 3DOF?

I'm planning to build a 3DOF front motor design, similar to the picture but with my own touch. I will probably be upgrading the lower and middle frame to 2 inch by 8 inch lumber to make it stiffer due to the wheelchair motor mount, and everything else 1 inch 16 gauge steel square tubing. The wheelchair motors I have are 18:1 gear ratio, 24V, but I'm planning to run them at around 26V. The question is, how wide should I make the upper frame connected to the seat since my wheelchair motors have an 18:1 gear ratio? The original designer used a 16 inch width due to the limited steel tubes but I have plenty at the moment. Would you recommend going bigger, smaller, or keeping it the same? After using the calculator here, it kind of got me more confused unless I was doing something wrong. The plan is to use the sim rig 65% flight sim BMS, VtolVR and 35% racing. Would you suggest making similar angle rods or differently?

A bit this DMax design does not fit for flying in BMS
see this design
https://www.xsimulator.net/community/threads/diy-3-dof-inspired-by-dof-reality-h3-model.18273/
much more compact
I had two similar for flying (wooden and metal ) and this layout for flying with motors at the back was great.
The 18:1 ratio doesn't tell you much, how much RPM ( revolutions per minute ) do your motors have ?
What maximum current do they draw in Amperes

Will you be using a third motor for the TL ?

I have 3 identical motors, the same motors that DMax used in previous build wheelchair motors. I posted a picture of the motors in the first post. I didn't get a chance to measure rpm yet but from a quick glance they are 18:1 Why do you think motors in the back design is better for flying? The design looks great but I don't think my motors will have enough torque for the design.

Please provide a link to the DMAX video showing your example.
Generally, in the arrangement shown by Dmax,
the motor-arm arrangement is inefficient (red lines in the diagram).
The angle between the arms and the rod should be 90 degrees when the platform is at rest (green lines in the diagram).
The platform I linked to is modeled after the DOF Reality H3, which uses motors with a power of about 200W.

This is how you fly on a platform with two 250W motors at the rear.


What motor controllers do you want to use?

I'm planning to use IBT2 at 26v - 26.5v

Here is the video to the motors that I'll be using. Please skip the video past 16 min

Don't buy IBT2, they are very unreliable. In order for them to work properly, the supply voltage must be reduced to 18-20V. Above this voltage, they are easily damaged.
I burned 8 of them myself before I found these controllers.
https://www.xsimulator.net/community/threads/reasonably-priced-100a-motor-controllers.17638/
They are reliable and do not heat up at all.
The only difference is that smc3.ino must be set to MODE 1.

Translated with DeepL.com (free version)

missing picture

I second this. Save your time and money. Get the 100 amp ones from eBay

According the

I guess back EMF is killing IBT2 and requires additional diodes protection to be installed.

I am not an electronics engineer by training, but there are plenty of posts about burnt IBT2s, so it is better to buy slightly more expensive but more reliable 100A controllers than spend weeks looking for the reasons why the motion platform is not working.