First attempt - 6DOF and learn to TIG weld at the same time.

Curious how many amps this draws on your house voltage. Do you have to spread this out over multiple breakers? Would this run off one 120v outlet?

Thanks again!

Thank you. And, yes, I'm planning to post the measurements and BOM. I figure it's the least I can do, and it might help someone else get started. It may not be until the weekend, but I will get some stuff up here.

As for the power draw, I haven't quantified it yet, but I can tell you that the computer and simulator were both running on one 20 amp circuit last night with no problems.

I've had some questions about measurements, materials, etc. And, since I don't have much else to offer the community, I figured I'd at least put that stuff here, because when I first got the idea to build a rig, I pored over other build logs and photos trying to glean that kind of information. Again, I used others' ideas (and didn't execute them all that well) so if you're just looking for a foothold to get started on a build, this might be useful, but there is plenty to criticize!

CONSTRUCTION
I used 6061-T6, 1/8" wall thickness aluminum tubing that I purchased from onlinemetals.com


Connecting rods – M10-1.25 threaded rod from Fastenal.com. Mine are 13 5/8” long (~346 mm)

Tie rod ends – SQ10RS ball rod ends that came from China via ebay.


Lever arms – 1 ½" X ¼" steel bar from Lowe's (a home improvement store in the US). CTC distance = 80mm


Gas struts – 550 mm bonnet/boot gas struts from ebay. These help the motors lift the platform when it is loaded, and I attached them at the vertices of the upper frame and midway between each motor pair on the base.


POWER
I have six, 12V/50A LED power supplies (ebay), all wired in parallel with each other and with a 12V lead acid battery. There is a battery disconnect switch on the negative lead from the battery to the power distribution bus (the green 3D printed part between the LED supplies and battery in the photo below). All connections between the motors, Sabertooth motor drivers, battery and power supplies are 8 gauge flexible wire.


MOTORS
I used 12V crab pot puller motors, with 50:1 gearboxes, purchased from seller pgsaw on ebay. When they arrived, I took the gearboxes on three of them apart, and flipped the orientation of the shaft, to keep things symmetrical when the motors were paired on the base.



MOTOR CONTROL
I had originally planned to use Thanos' AMC1280 USB controller, but just couldn't get it to work (though I still hope to, some day), so I went with the more commonly used Arduino/SMC3 solution. I bought 3 Arduino UNO clones from Amazon and installed this sketch.

The Arduinos receive motor position information from these sensors


I did not use shielded wire for the sensors, but I braided (plaited) the lengths of hookup wire, and that has worked fine (though it was extra effort).


Each Arduino is connected to a Sabertooth 2X60 motor driver, and that pair controls two motors. So, for 6 motors, I have 3 interfaces of two axes each defined in Simtools.



Those interfaces correspond to these motor/axis pairs on the simulator.


And, finally, for the sake of completeness - since part of the rationale for this project was learning to TIG weld - the welder I bought was the AHP Alpha-TIG 200X. I like it a lot.


So, there it is. I hope this will be helpful to someone looking to get started.


The rig is not at all elegant compared to most that I've seen here, but it works. I plan to make a new upper frame, which will let me mount the seat within it, instead of on top as I currently have it mounted. This will put the connecting rod attachments closer to shoulder height, reducing strain on the motors, and making the center of rotation more natural. I am also still thinking about how to wire in a kill switch (though the SMC3 utility provides clipping and max limits for all motors).

For now, though, I'm concentrating on trying new games and learning about refining profiles. If any of the more experienced builders see anything in the above that is wrong, stupid or dangerous, please chime in. I don't want to promulgate bad information.

And, once again, many thanks to all who helped me get this far!

Reinforced my connecting rods with some 1/2" square steel tubing today. The M10 threaded rod wasn't bending, but it didn't exactly inspire confidence in potential riders, and my parents are going to give it a try tonight.


Anyone else who uses pgsaw motors with the hollow shafts having trouble keeping things from slipping? I tried using thread locker and grub screws on the nuts that "pinch" the hollow shaft to keep the bolt that serves as my motor shaft from spinning free, but that kept slipping. So, I drilled through the holes in the motors' hollow shafts and put cotter pins through the bolts, but one slipped today and sheared off the pin. I didn't want to resort to welding the motor's hollow shaft to the bolt, but I may wind up doing that unless someone has a better solution?

Also printed some mounts for the little Dayton Audio pucks I'm going to mount to the platform since I couldn't justify the cost of Butt Kickers. We'll see how they work out.


And, finally, the very talented son of a friend of mine dropped by to help me create a plugin for Lunar Flight. We're just about finished testing, and he's going to post it (only fair, since he did all the hard work), so keep an eye out if you have that game. It's fun!

Hi, have you found a way to prevent the shafts from spinning? I too am using a cotter pin with the hollow shaft but I noticed it's significantly bent after a short amount of testing.

Yeah, I don't think the cotter pin was a great idea. Mine bent as well, and two sheared off completely. Plus, drilling the holes for them weakened the bolts, as I found when I went to tighten one and snapped it in half. Right now, because I'm lazy, I'm waiting for each bolt to fail before replacing it (so far, none of the others has). When I do replace the bolts, I'm thinking about welding the nut and bolt to the long side of the hollow shaft (the "inside" on my set up) in some way that I can easily grind off the welds if needed to get the bolt out again. Beyond that, I don't have any other ideas. But if you come up with a better solution, please share it!

Same here. When I drilled the bolts the remaining part seemed too thin to support the loads. It didn't break yet, but a matter of time. A small improvement could be to use fine threaded bolts if you are not already doing that, as the threads, hence the spacing, are smaller.

I'm now thinking of getting a 1/2'' diameter keyed x 5 or 6 inch length shaft with a slotted key so that the middle section of the key fit into the motor's hollow shaft, and then welding them to the hollow shaft.

The slotted key I'm thinking of is full height on both ends and lower height in the middle. Not sure if I got the name correct term, and I can't post images or links as I don't have enough posts yet.

In hindsight, having spent so much time on the bolt based setup I wish these motors came with a nicer attachment option.

When you get that set up, would you mind sharing some photos?

I see motor is made in China, looking forward to your new progress.

Use exterior star washers on both sides of the shaft and I think those shafts fit a 20mm bolt. Just get a fine thread in a high strength bolt and lock nut and crank it good and tight. Mine never slipped no matter how much it was abused.

Thanks! I'll give that a try.

Why didn't you go for 24v motors? Then you could have used less beefy h-bridges and wires.
Cheers
Ed

Mainly due to expense. I also had no experience, whatsoever, before taking on this project, so I decided to go with what worked in the builds that I was emulating, and try to keep the expenditure as low as I could in case of failure Like others have, I might upgrade to DIY linear actuators at some point.

Hey @Squonk, did you get the arm slippage on your output shafts sorted? If you didn’t, and I’ll probably jinx it now, so far I’ve had no slippage with a custom clamp arm and a roll pin (https://www.xsimulator.net/communit...ks-wind-flying-driving-rig.11281/#post-152778). My C-C is 45mm though so the motors have a bit more advantage than with an 80mm C-C.

@Zed, I haven't had any slipping problems in a while, but your clamp looks like a great solution. I wonder if there's an online source where I could get those made from your drawings at a reasonable price. I have shortened my CTC distance to 55 mm, and that seems to have helped - as has entering really (I mean like, "this can't be right") low values for Kp and PWMmax in SMC-3. I was getting really juddery movement until I did that.

There definitely are places to get them made in the US and as long as you go uniform thickness, cutting just the outline is pretty cheap and maybe a quantity discount for six. I drew mine up with flats on the sides tangent to the output shaft so I could just mark, clamp, and drill the holes for the roll pins, as well as the hole for the clamping bolt.

I forget the company name but there are a number of online machine shops that do these kinds of jobs pretty cheap. The one I was going to use had free design software that you just draw the outline, specify the material and quantity, and they will generate a quote automatically. I don’t remember what they quoted me but I think it was around $40 for a pair.

Just search for online machine shop and I’m sure you’ll find them. I just went with one of the top hits to get an idea where I was landing price-wise. Turns out a friend of mine volunteered to cut them for me and went a bit nuts.

Glad the slipping is near fixed or fixed!