Mr Burn's simulator

So, after reading for a week, I decided to start work on a moving chair. (Ich kann auch deutsch ein bisschen, war 4 Jahre in Heidelberg auf der Uni).
It's a little messy with the instructions , so I'm not 100% sure what I'll need, I guess I'll find out as I go : .

For now I have the following:

Aluminum profiles (hopefully enough for the chair part - won't do the wheel or pedal part for now, just the moving chair frame part) and brackets to connect all the stuff together. A seat from the junk yard that can be adjusted forward/backward and up/down.

I am missing all kinds of plates,rods and dampers I see in the drawings around here. No actuators yet, not sure what to go with here, does anybody have any suggestions? I don't want to spend more than $500 per actuator.

I will try to post pictures as I am building it, I'm sure I'll come across things where I'll need help. Thank you

Update:
http://www.youtube.com/watch?v=1puoQoaCl68

First, something I should say about metric components in the US. If you don't have to get metric stuff, don't. It's a nightmare to find anything in metric sizes that fits. You will have to tap and rethread some screws and/or bolts in order to make everything fit. Also, don't underestimate the cost of scews, bolts, washers, whatever. It all adds up fast .

To start:

1.) 7332 mm of 40X40mm aluminum profiles. They are in different lenghts, I was trying to avoid having to cut too much, but some cutting will be needed.
2.) 40-50 M8 angle brackets to connect all the profiles
3.) 50-100 M8 1.25 16mm button scews to connect the brackets to the profiles (this was a nightmare to find, the stores would have 5 metric scews and that was it).
4.) 5-8 clevis pins with pin clips to connect balljoints (from the actuators to the base, rods that need to move etc).
5.) 6-7 T Plates
6.) 50 T-Nuts to use inside the profiles to connect them together with the brackets and screws, as well as anywhere else that they are needed.
7.) Female balljoints and female balljoints with studs. 2 of these need to be rethreded to match the 10mm scn5 actuator connections, the rest can be used the way they are.
8.) Seat from a Pontiac Grand Prix
9.) 2 scn5 actuators

Missing some bolts and washers to connect the seat frame (Sitzramen) to the base (Grundgestell). I have a plan on how to connect them, but I don't know what to use for the part that bends with the seat frame? Any advice? I was thinking some sort of U-Joint (universal joint), but they seem to be huge and heavy. Any advice?

For the seat-frame/base-frame connection you should use a rubber silent block with threads on both sides



Mine have M12 threads. Dont know the corresponding size in inch.

Have fun!
Christian

Thanks for the help. How does the rubber hold up to the constant movements, does it need to be replaced once in a while?

Edit. Got one from vibrationmounts - http://www.vibrationmounts.com/RFQ/VM02015.htm (V10Z52-FB0550DD). It should hold up ok I think.

yes, that model should do the job.

Regards
Christian

I'm not sure how important it is, maybe someone else can chime in here, but if you're designing what I think you are, then allowing the seat to slide forward / back on a traditional slider mount will alter your center of gravity and place alot of undue stress on the actuators. I'm designing my own seat base, and the entire mechanism, including actuators slides forward and back, keeping my center of gravity the same, and placing the minimal load on the actuators.

Also, U-Joints can be purchased in a variety of sizes (Not just car / truck sizes) like small tractors etc.. I am planning to use a smaller on that I found, which will alleviate the need for tie-rods to prevent rotation and if I am correct, will hold a larger amount of my weight than other designs that I have seen.

Good luck with your project,

Bernard (bvillersjr)

That's correct, the seat can't be moved forward/backward unless the actuators will move with it and preserve the center of gravity. For now it will not be moved, might make changes after it's done for movement. The wheel and pedals can be moved forward, backward so it's not a big deal.

I have seen smaller U-joins, but most people don't seem to use them. Tom Theison posted a video here (http://www.megaupload.com/?d=N10ODDH0 and the thread my-future-motion-cockpit-t132.html?hilit=vibrationmounts). He is using one of the diamond rubber mounts and doesn't need to use any straps, I guess I'll do something to the design if it wants to start spinning .

Some more pictures and a question. We are out of t-nuts and can't find them anywhere, so will have to wait for some.

I don't know how to balance the seat on the seat frame? The back of the seat frame with the cross-like section that pushes/moves the seat around is heavy (and it's not even complete yet), the seat with the seat frame will always fall backwards because of that (even if I sit in it), no matter how I move it around. When I add the actuators arms with the actuators in the back, that will hold it straight, but I don't think there should be any weight on the actuators and it should be balanced. So how to do that? Are the actuator arms supposed to hold it at all?

I'll be going down the same route as you. We should think about putting some instructions together with the dimensions of the TSLOTS, seat frame position, etc. I'll put something up when I get to it, but great work so far.

Thanks, I'm almost done with it, will write some detailed instructions after that. If you're in the us don't get metric aluminum t-slots for sure.

To make it balance straight I am thinking of connecting everything together, moving the actuators arms in the middle (they are 150 mm), so at 75mm and then having the seat be level. Put the pivot towards the rear of the seat but not too far. And then adjust from there if it's going to work.

You are right, you want as much of the weight balanced as possible. My design is a bit different from yours, and I used a universal joint as the mounting point. I had to balance it on the universal joint, but that balance is a little different than it at first appears. Remeber that you will be sitting in the seat with your arms and legs extended, which definitely alters the balance in a major way.

I look forward to hearing more about your progress.

More pictures with the seat frame in pieces and the seat attached to the frame. The seat frame with the seat can now be connected to the base and the 2 rods can be connected, then attach the back to the actuators.

:mug1:

Hi guys here a tip as to the way i balanced my car seat on my platform ..Basically it is also mounted on CAR prop shaft Universal joint .. i monted the seat to a flat piece of 18mm MDF and placed a round tube under the MDF and onto a FLAT surface ( My imitaion pine wood Floor : ) i then sat in the seat and with my legs lightly supported and arms forward mimicimg grabbing steering wheel, and gently rolled the whole setup back ward and forward to find the balance point then marked a on the board transferred it to the seat mounting bracket ... seems to work ok but will put a weight scale behind the seat to see how much force it exerts on the motor arms when my 110KG lump is sitting in the seat :yippiee: just a thought sorry to chip in on your posts : still have a small bracket to weld to my prop shaft support bar but will post pics on saturday

No need to be sorry , this is what the forum is for, I am open to any suggestions - especially since I was supposed to have 2 other people help me and that didn't happen , only one person once in a while to cut things. Stuff will be off probably since it's hard to do everything with 2 hands only.

My 150mm SCN5 should be here this week. Yes I am in the US but went with all us hardware and 1.5 Tslots.

I think its wise to make the system as rigid as possible. One area of concern would be the seat back. The stiffer we have the seat (1-piece seat is probably best) and the tighter your link is to the back-top portion of the seat, the more you would feel the slight movements of the SCN5. The units where they bolt the SCN5 to the back of the seat make sense. There should be another method of achieving the same results.

How wide is your base? I'm shooting for 31 total with a 28 center width. I've seen videos of these FREX units and the base itself lifting from fast movement. Frex definately should have used better material imho.

The base is 33 and a little bit wide (840 mm or 84 cm) but it's the same width all over, I'm not sure what you mean by 28 center width.

The profile with the pivot is about 24 (610 mm or 61 cm) from the end and the pivot is right in the middle of that and I put the pivot almost toward the end of the seat for now.

I connected the actuators to the arms today by drilling through the aluminum and putting some screws through it but it didn't end up looking very good. :thbd: (used some aluminum to connect to the scn, didn't drill through them of course), I have to change some of the mouting tomorrow to make it better.

For the ball joints that connect the actuators I used the same 90 degree mounting plates that are all over the place but I cut the edges off so the ball joints won't hit the sides. You will need something smaller if you use the normal 90 degree plates for that.

Sorry, I'm not very good with us measurements, that was why I got the metric stuff, I can't really work with non-metric numbers. :no:

Finally after another night of cutting fingers and hands and such :lol: I put together the first final assembly. I had a friend help me balance it initially (as good as we could - it was a constant fight with it twisting and turning and falling one way or another) and then make it level with the actuators at 75 mm. I don't know if I should do anything else to it for now before I connect the wires?

Made some changes, lowered the seat b/c the stabilizer rods angle was too high and they were touching the side of the seat frame when one actuator was at 0 and the other at 150mm. I know they won't be used on the whole range, but it was a little odd. Also moved the base rods connection to be in line with the pivot and fixed the seat leaning a little to the left because of more weight on that side.

Added some spacers on both sides of the actuator ball joints (top and bottom) so that they won't move horizontally.

Moved the pivot a little back b/c the front was hitting the aluminum profile when both actuators were at 150 mm.

Ok, now that most of it is how it will be, here is some information on how I would go about making the frame (looking back at what I did)
Depending on the size you will need a different sizes, but here is what I ended up using:


- All the aluminum profiles (40mmx40mm), 90 degree profile connectors and t-nuts came from http://www.8020.net/ (they are on ebay too).
This stuff will need to be cut, don't plan on cutting the aluminum by hand, you need some power tools.

-The ball joints are from napa (http://www.napaonline.com) - you have to go in and ask them for the stuff.

-Threaded rods, T-plates,bolts, spacers, nuts, washers etc from http://www.fastenal.com or http://www.acehardware.com - have to go in usually.

-Pivot from http://www.vibrationmounts.com/ (diamond shaped base mounted)

-Seat from the junk yard

- Ac-Dc power supplies 24V 2 amps from here http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0125629218
You can use industrial type power supplies but you will have exposed 120V (or 220V wires), so unless you have a cabinet for them I wouldn't use that kind.

- Serial pci card with 2 connections: http://www.tigerdirect.com/applications ... Port%20DB9

-rs485 to rs282 from ebay (http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0298949916) but I don't know if they work yet.




0.)All the aluminum profiles will have to be cut to the correct length. I cut them as I progressed, kinda decided what the length should be when the next piece was needed.

1.)Base, very simple. Decide on the length and width and just connect the pieces with 90 degree connectors. The profile that that will hold the pivot should not be tightened b/c it will need to move forward or backward.

2.)Seat frame and connect the seat to the seat frame. Rear part of seat frame assemebled and connected to the back and then connect the seat to the seat frame so that it is as tight as possible on the rear push bar, but not actually putting weight on it.
Depending on the type of seat this will be different. I drilled the seat rails and connected it with normal screws that I use everywhere and t-nuts. The seat can be drilled in the back and connected to the push bar, so it will be a tighter connection. Used an aluminum plate of some sort to connect to the underside of the seat and put a screw through it into the pivot (the pivot should have a threaded hole for it). Now, if the seat is heavier on one side the aluminum plate can be moved a little towards that side to compensate so that the seat frame won't tend to fall into the heavier direction. If it's of equal weight the middle should be good.

3.)Connect pivot to base frame, ideally in the middle.

4.)Connect seat to pivot and try to move the pivot towards the rear where all the weight will be when sitting in it(I did this without the back seat piece attached, attached it later). Another person should help here, the balance should be so that it should ends up sort of like a rocking chair. To adjust the profile that is connected to the seat and pivot can be moved towards the front or the back.

5.)Once balanced move the aluminum profile that the pivot is on (of the base) towards the rear so it is 18-23 cm from the back of the base. This will move the whole seat frame with the seat. It should maintain the balance from 4.) since everything moves at the same time. This can be done before 4.) too.

6.) The frame with the seat should now be held level. The profiles that will hold the actuators should be measured and cut so that they won't hit anything and will be long enough. Length will depend on if dampers are used, how they are used, etc. I didn't use anything, so I cut the profiles to be a little lower than the height of the seat frame. Attached the actuators and made sure everything was level with the actuators at middle position (75mm in this case). To connect the actuators to the profiles I used the 90 degree connectors and some spacers so they will just move from the ball joints and not horizontally with the whole profile.

7.) The stabilizer rods should be as low as possible so the seat won't hit them. They prevent the seat from spinning. Nothing should hit the ground at any position. The ends of the rods that are connected to the base should be the same distance (or very close) as the distance of the pivot from the back of the base.

8.) That's it. Sounds easy if you've done it before that is.


I used 26 90degree connection plates, 1 T-plate, 6 female ball joints, 2 male threaded ball-joints, 2 L shaped aluminum plates, around 100 T-Nuts, 20-25 washers, 10 steel spacers, 2 threaded rods and the aluminum profiles (40X40 mm), around 100 M6 screws, 2 extra screws for rods connections to the seat frame.


Dimensions:
Base
Length: 59.6 inches (151cm - 1510mm) - there is some space in the front to attach something like a wheel holder
Width: 36 inches (96cm - 960mm) - there is space to the sides to attach gear shifter, keyboard etc.
Length of aluminum profile inside the base width (the 2 shorter profiles in the base) - 33 inches (84 cm - 840 mm)

Seat frame
Length 31 (78 cm - 780 mm)
Width 19 (48 cm - 480mm)
Height 30.5 (77cm - 770mm) - height of profile in the back that is 90 degrees to the seat frame is 29 (73cm - 730mm)

Height of actuator arms: 29.5 inches (75 cm -750 mm)

Height of side of seat frame from floor - 4.25 (11cm - 110mm)



I will add more where while I remember what I did.