Carl's upgraded SCN6 2dof motion sim

[Carl]

Well after a lot of soul searching I decided the time was right to upgrade my pololu 12v12 wiper motors with SCN6's. As everybody knows these are very pricey so I had to sell some kit to buy some kit. The laser cutter went and the SCN6's came. A very good trade.

I started out on this project last year after stumbling across X-sim by accident trawling the web. My first motion simulator utilised the same platform + 2x pololu 12v12s and wiper motors. Although it was great fun for my 8 yo boy it definitely lacked the grunt and range to keep me happy.

I built my platform mainly from bits of scrap salvaged from work

The parts I have purchased so far are as follows:

Fanatec GT3 wheel - £70 off ebay
Fanatec Clubsport pedals - £150 off ebay
Racing seat with rails (fully adjustable) - £50 off ebay
MGB Drive shaft / universal joint - £20 off ebay
7.5a 24v PSU - £17 off ebay
2x SCN6 40 150's - $1,841.72 USD(£1,108.64) (+£150 import duty) from Mirai
2x 14x1.5 teflon lined rod ends - £20 from Mcgill motorsports
4x 14mm/12mm reducing misalignment bushes - £10 from Mcgill motorsports
2x USB-RS485 converters - £30 off ebay
2x USB 3m extension leads - £10 off ebay
2x 2.2k resistors and 2x 27v zener diodes - £1 Maplins

Total parts spend £1,636

Parts and materials I have rescued and re-cycled from the skip at work
An awful lot of 6mm thick alloy chequer plate (3x 1.6mx1.0m sheets)
2x part used articulated pneumatic cylinder mounts

The tools I have to hand and used to make this were as follows:

Pedestal drill
Jig saw x2 (burned my first one out cutting all the alloy chequer plate up)
Mains drill
Battery drill
Dremel
Chop saw
Table saw

Time to build
Although I have spread the build almost over a year I estimate the actual hours spent working on this to be in the region of 80-100 hours.

As my platform is mainly metal and aluminium I also ended up buying an awful lot of nuts, bolts and drill bits during the build and I am now on first name terms with my local hardware store owner... in fact over the last 2 months I am probably his best customer.

My design has evolved over the past 12 months as it came together but the basic premise was to build a platform somewhat similar to Floriske's playseat. To that end game I don't think mine is too far away.

I could have tried to make it straight off the bat from CAD designs but to be honest I think the trial and error route is a much more enjoyable experience. I had several difficulties to overcome during the build with weight being the primary obstacle. To get around this I used a couple of gas struts underneath to balance off the weight of the front end of the upper platform. It is very well balanced at the moment with no load experienced at the motors when I am sat in the seat. I got quite nervous about the pivot point from my original design and shifted it back to directly under the seat when fitting the SCN6's. I have posted a cad drawing to show the geometry and dimensions of my design.

I tried to follow the instructions on wiring the SCN6's to the letter but also added some little touches of my own. I used some spare xlr chassis sockets and plugs to create an interrupt / isolation point between PSU and drives for when not in use. I mounted these onto an old psu case and also hid the usb rs485 converters. I also added an e-stop relay instead of wiring direct to the ilk pin. I have posted a full wiring diagram and show the basics in my scribbled schematic drawing.

Here are some pics and vids of the build as it came together and also of course as it is now.

[Carl]

Here are the latest pics taken in April 2014... now to set up my maths outputs... yay.

This is my simulator in all its glory.

One of the mounts I made for the motors using some extruded channel (22mm) and some 10mm alloy plate

I ripped apart an old linear psu and stuffed the fuses and new switch mode psu inside. I also used it as a jb to connect up my safety circuit and relay plus some thermal trips. The green illuminated switch turns on mains and the flip switch turns on the 24v.

Here is the other end with the drives, xlr plugs, and rs485 converters

as you can see from this pic the misalignment spacers are fitted on the rod ends. probably not needed but thought they would be a good idea

[Carl]

Had my first full race tonight with 80% longitudinal, 60% lateral and 75% z axis forces... very cool indeed. Im very happy with the speed, feel and amount of motion. I will record a vid tomorrow to show it in action. Now I Just need to be creative and design some guards for the scn6's and finish off the safety stuff. I need to fit an e-stop near the wheel within reach and guard around the scn6 to protect against against the pinch point.

[nclabs]

As you can see, the forum it's really quite. Nevermind. Congratulations for your sim, I did myself one with your very same actuators, boy, they are awesome, but quite expensive. If you want we can exchange some infos!

[Carl]

[Carl]

https://www.youtube.com/watch?v=YIvGWEJsro0&list=UUFiL0EvQ1AzwMRiywlI5cjw

[prodigy]

Nice motion Carl, no big throws and swings, it's just enough. Nice work.

[Carl]

Thanks Prodigy.

I found if you put too much motion in it tends to detract from the gaming experience and you end up adjusting your driving style to avoid being thrown from side to side in chicanes etc. Not so bad if you want to learn to drive like Jenson Button but if your aggressive on the racing line and kerbs it can be off-putting. I think mine is using at max approximately 100mm of the 150 available. I also have smoothing and spike filters running in the background on each axis. I would probably increase it for flight sims as the motion forces generated are much more subtle but when the motion is coming on quick and fast as it does in driving games its best to throttle it back a little.

Hi nclabs, a little collaboration would be great. I'm keen to hear your experience with the scn6's and very much interested to see what you built. PM sent.

[Carl]

Here is the basic design and dimensions of all the main mechanical components that go toward my platform build


These images show the platform before the upgrade coming together, notice the single plate base and position of the pivot
I widened the base front and back by adding the out-riggers. I discovered the need for widening the position of the feet when I started testing my old wiper motors... it was not very stable at all. Now it is rock solid.

[Carl]

Here are the components I made to mount my scn6's