Motors orientation in a 6DOF

[Arno]

Hello,

When building a 6DOF, I have usually seen the pictures showing the back of the motors towards the outside of the simulator.
Please check this CKAS picture for reference:


Would it be possible to orientate the motors 180 degrees so that the back of the motors are actually in the center of the simulator?
Basically, flip the motors/gearbox combo.
This would allow to not have the motors protruding as much from the simulator...

Ideas?
Thank you.
Arno

[telfel]

This looks like a compact setup

Can I ask which 6dof software / hardware you are intending to use?

I am planing to use this type of layout with a horseshoe type top platform (open front) with the seat suspended under the frame.
which requires one of the motor pairs A frame (pushrods) to be located at the back of the seat.

[Arno]

I purchased Thanos's PCBs a while back and will use that.
The reason why I am trying to find out if I can put the motors with the axis on the outside is because the motors I am looking at have the rotation axis on the end, instead of on the side like on your picture.
Arnaud

[telfel]

As I understand it, the setup is based on the diameter of the base joints, to the diameter of joints on the moving platform, to the length of the pushrods, so the position of the motors inside outside etc should not make any difference, the only problem I can see is the clearance between the crank arm and the lower pushrod ball joint, large angle spacers are available to give greater clearance.

[Arno]

Thank you for the comments.
I did think about the clearance issue and I think that we should be fine there, I need to do a quick model to confirm that.
Being able to put the lever on the outside allows me to put the 6 motors butt to butt in the center.
I think that this will gain quite a bit of room compared to the other way around.

[tronicgr]

Hi Arno,

You can place the motors inside, no problem with that. I did it in model already: http://motionsim.blogspot.com/2013/11/6dof-mini-servo-platform.html

If you afraid for the rods that might hit the motors in excessive angles, you can just make the top platform a little bigger (top triangle).


I'm making another miniservo model with low profile 6DOF like the ckas low cost one, to verify the motion limits, soon on my blog more information about it...

Best Regards,
Thanos

[Arno]

Hello Thanos,

Very cool, thank you!
Funny, I sent you an email earlier this evening.

I finally purchased SEW motors and gearboxes.
I got 7 of them (1 spare), 0.75HP and about 50:1 ratio.
A bit too fast, but I will be able to slow down the output of the motor to get a gearbox output under 20rpm.



Pretty excited right now, I just need to find more specs on them, a bit difficult at this time...

Cheers,
Arno