DIY 3DoF Simulator for Research

Hello,

I'm building a 3Dof simulator for research (seriously ). I guess the amplitude and tilt angle are probably larger than most gaming simulator. Amplitude is 6 in (12 in displacement). I've finished the mechanical designing part. Here are some figure showing the CAD model. Most parts are made of steel.

Base:

U-joint (better for large angle than a single ball joint):

One thing I'm not fully confident is the crank:


I'm not sure the connection between the crank and shaft is good for long term use. The motor I'd like to use is this.
Anyone have any idea regarding my crank?

I'll update when I have more progress. Happy new year!

--------------------------------------------
It's been a long time...

I have to modify my design a little bit and finally made some progress on the machine. Square tube has round corners. There is not enough room for me to mount the motors. I've made three motor bases.
I used angle aluminium to make the mounts of potentiometers.

Two out of the six through holes in the motor shafts are off-centered. Luckily, I only made three cranks before noticing this.

I think it's time for me to test motors. I brought two Sabertooth and one Arduino. Anybody know if I need to buy another Arduino to control three motors? This post (
SMC3-SPS Sabertooth Packet Serial PID motor driver w/SoftStart
) only support two motors. I think Arduino is able to give 6 output channels which should be enough to control two Sabertooth. I do appreciate it for any direction!
---------------------------------------

05.22
Everything is wired up and ready for test. I have some problem. The movement of the motors is not smooth at all. Here is a video showing sudden movements when I Output Testing them in Simtool. I was dragging the slide from one end to the other end slowly.

Does anyone have a idea what may cause/solve this problem?

looks good !

what made you choose 3dof over 6dof

when do you start building ?

Cost is one reason. And 6dof is actually not necessary for my project.
I'm gonna order materials next week. Hopefully I can start the week after next week.

Just realized that I can modify my first post. LOL. See update in my first post.

---------------------------------

It's been a long time...

I have to modify my design a little bit and finally made some progress on the machine. Square tube has round corners. There is not enough room for me to mount the motors. I've made three motor bases.
I used angle aluminium to make the mounts of potentiometers.

Two out of the six through holes in the motor shafts are off-centered. Luckily, I only made three cranks before noticing this.

I think it's time for me to test motors. I brought two Sabertooth and one Arduino. Anybody know if I need to buy another Arduino to control three motors? This post (
SMC3-SPS Sabertooth Packet Serial PID motor driver w/SoftStart
) only support two motors. I think Arduino is able to give 6 output channels which should be enough to control two Sabertooth. I do appreciate it for any direction!

i think the smc3 will support 3 motors if you use pwm channels

however another arduino is cheap and will not add much cost to the project

program the smc3 and get the test program working

Thanks! I found a code wrote by Wanegain which is good for up to 6 motors using only one Arduino. It works, suppose. At least my motors are moving. But I think they need some tuning as the movement is a not smooth at all.