Showroom 6DOF Compact Rectangular 7 Actuator Motion Platform (Not Stewart)

Hi Everyone,

This is my first DIY motion simulator project. It is still a work in progress. Materials have been purchased for a modded SFX100 with 150-180mm stroke, Item24 aluminium profile (300mm) instead of kinetik, and reversed longer linear bearings (LMEKL30UU) with longer hollow shaft (380mm). I still have to buy the materials for the surge and yaw/sway platforms. The longer shaft would allow to attach the rig to the actuators in a way that the mouting and turning points on the rig can be higher up, so a roll becomes more of a roll-like and of a less surge-like movement.

I already have the 3d printer, and placed the order for 7 x 90ST-M02430 motors with AASD-15A drives, a Thanos AMC-AASD15A Servo Controller, 3 x modded GX150 with dust cover and 300mm stroke, and 4 x ball-bearing hinges from Item24 to connect the motors with the platform.

The surge platform will be just a simple linear rail with sliders, nothing fancy, that's the easy part.

The difficulty came with implementing the Yaw and Sway elements in the bottom-most platform. I never liked the idea of caster wheels and saw a video on the Thanos discord channel which inspired me to create a design for this. I looked around for CAD software and found Fusion 360 to be looking good and free. It also makes sense before I buy all the hardware, to make sure it is going to work out well at the end. I am very new to CAD software, I only started learning it 4 days ago, but the idea of building this platform helped me get up at night - in a good way

I would really appreciate the input of the veterans here, people who have experience with building motion platforms.

I have a hard time figuring out the joint placements and rod lengths for the connection between the linear table and the platform. Are there any guidelines or formulas to make their movement as optimal as possible?

I am also still trying to figure out a clean and precise solution to connect the surge element shafts with the SC linear bearings that move along the sway shafts. Maybe I should just 3d print or CNC (outsource) a plate that fits exactly.

Cheers,
David

credit goes to @fredbalcou at Thanos discord for the inspiration on the wheel-less design. Here is his video:

Nice modeling, so that the link does not break your head, directly connected the bearing to the actuator table, no need to connect the upper part to the lower part.

Nice project. Like to see new ideas. Good luck

I quite like the idea of fixing the yaw and sway DOFs in the middle. I am starting to figure out the joints, I have adjusted the design a bit here and there, moved the motors further away from the center, designed the shaft holders to be 3d printed, have changed one of the motors to the real GX150. I just need to adjust the length of the GX150 to be double the size, to match the one with 300mm travel and dust cover, and reconnect the bottom joint to the GX150's table. Some parts have arrived, still waiting for the motors and GX150s from China, and parts from Item.

EDIT: *motors -> linear tables. I just realised, I will certaily need some kind of clamping mechanism and may just go with drilling the holes out on the SC sliders for the SHF30 just as you did. The 3d printed parts may not hold the shafts strong enough.

Congrats, very impressive project... Well done.

Thank you.
Here are some updates:

Love this engineering design. My next rig.

Can you post your design specs so others can print/purchase parts as well?

Wow looking forward observing the animal in motion

Thank you! It is great to hear that I will be open sourcing the design, I am getting everything together now, finalizing the parts list. When are you planning to build it?

Testing DoubleTL full stroke with the Thanos controller:
4 actuators + DoubleTL with SRS and DR2.0:

First Motion Simulator? New in CAD design? Man, you are good...
That rig is incredible! Congrats

Thank you. I never thought what a PC build and simulators in general will drag me into Lots of new things learned... It feels so liberating to be able to design something in 3d then manufacture it (CNC or 3D print) and to build physical stuff after so much abstract software coding...

Hi, very interesting design. great work. please let us know how the linear guides behave during operation with a load. thank you for sharing. unbelievably great.

Well, If building feels good Driving it is paradise. What a clever and pretty design David

As promised, here is the link for the open-sourced design: http://www.simmetrik.com/6dof-motion-simulator-platform

First motion simulation project, but you did it professionally. Thank you for sharing, hope to do the same as you in the future.

that is fricking amazing! Many thanks

well thought out congratulations on the project.