New 3DOF Flight sim project

Hey everyone,

I'm interested in building a flight sim for Star Citizen / Elite Dangerous but also something that could be used as a racing sim albeit maybe without all the same features that a dedicated racing sim would have.

From what I have read here, for flight sims, it seems it would have to be at a minimum a 3DOF sim but i'm not positive on all the details needed yet such as motors etc. I am not small at 6'2 and 260lbs (on it's way down lol) But i'm looking for something more than just a seat mover. I am also going to be using Oculus DK2. From my preliminary research I was looking at perhaps having this work with worm drive motors and 60:1 gearbox in a setup similar to this.



for the seat and frame I was thinking of using T-Slot Alu Extrusions. and the motion platform was going to be steel (I can't weld so i would have this done for me locally).

@noorbeast mentioned looking at @cthiggin 's build which I did. I really like that design and actually have looked at it in the past. What are the pros of a center spring assist design vs what I posted above ? I am also wondering what type of motors I should be using for whichever design would work best. I guess we'll start at the start and figure out the design to go with first and work on motors next ? That seems to be the trend from what i'm reading around here

Thanks and looking forward to getting to know you all during this project.

Achtepa,
I used the center spring through many suggestions here on the forum......and my "custom spring" cost 353.00 US to have made.
The spring "ASSISTS" the heavy weight of the loaded top platform, and helps the motors to work easier.....
After the build, I am "personally" convinced that due to the heavy duty gearheads and 1hp motors, I could have not used the compression spring and would have been fine.....
We learn as we go...........Also, LESS Spring - I could have had the top platform "closer to the floor".
The above design of the motion platform would work fine without support spring - but all is hinged on the size of motors - and how heavy duty the gearheads are.

Stay with it friend.

Tom

Thanks Tom.

By heavy duty gearheads, what kind did you use ? I don't know much about motors but after reading a lot of different builds posts on this site i'm getting very confused, i've seen some builds use 25:1 and others 60:1 from what I understand the gearbox relates to how much torque is going to be produced and perhaps load it can handle ? So if i'm looking at a total load of about 450 lbs What would be best for this kind of build ?

So you're also saying the assist spring is optional if i use heavy gearboxes ? What kind of clearance did you get on your platform ?

Thanks a ton for getting back to me on the initial post, your input is greatly appreciated!

Achtepa,
I'm using 1hp, 3phase motors, inverter duty (MUST HAVE inverter duty to hold up)..........
My gearheads are Boston - 60:1 - Output torque is 116 ft. lbs ea..........and the insides of these gearheads are built like a tank...........BUT, they are very expensive.....about 650.00 US each.
It took me almost a year to buy new ones on eBay - all 3 for a total cost of about 600.00 US....

Now, keep in mind, there are many other gearheads out there that will do the job, just like mine, in ratio and torque - for about 250 - 350 US each...and plenty of used ones - You MUST make sure
all motors and gearheads are identical in output, torque, motor speed etc.

My motors are 1800 RPM so a 60:1 gearhead gives me 30 RPM / Minute - based on a total of 180 degree of movement, the travel is reached in 1 second........
You can speed this up if necessary by increasing the frequency in your VFD's....

My motor guru and friend computed that will ALL 3 motor/gearheads, and a 4" Crankarm, they can physically lift 941 lbs....combined - He jokingly told me that in all probability, they would
raise a Volkswagon....

SO, some more data for you to digest...............believe me, it ALL comes together when you are least expecting it too.

Tom

PS> MY platform is 26" from floor to top platform base.........which requires me to use a small stepstool. No biggie, but I would like to have it closer to the ground.......

Thanks Tom, Thats definitely a lot to think about and i'll do my research as 650 for each is a little outside my budget as I had planned for about $2000 for the entire build (not including pc).

Achtepa,
YES, I thought I could come in around 2,000.00 also - but, just doesn't happen for this type of platform......
When you consider VFD's at 130.00 each, ALL the electronics, nuts/bolts/steel/welding wire/grinding disks/paint - and ALL the other little things you never think about.........it sure adds up.
Plus, I built a dedicated hi-end PC for my platform that come in around 2000.00 - Plus 600.00 for wheels / pedals / and RS1 Sim Seat at 1600.00, 42" TV / ButtKicker / Logitech Z906 sound
system...............In summary, I'm approaching 7 thousand...................BUT, I do know that it would have cost me nearly double to buy one set up like mine.

I am convinced NOW, that I could build mine for 1/2 that............but sometimes, in-sight is costly..........

You can build a 2DOF that will do a GOOD job for both FlightSim and Racing (all in the setup profiles) for around 1000.00 - that's the motion part only - the other peripherials, "me feel" could be
done for another 1000.00 or less..........

I am NOT trying to DISCOURAGE you, but being honest and honest about what it cost me to do a 3DOF, AC Platform.........

Again, you can get good movement and happiness in a 2 dof and come in on your budget...........

Don't stop the dream now...........

Tom

Oh ya, i'm not actually including anything above the platform, i'm talking strictly Frame, Motors, electronics and platform for the chair and stuff to rest on.

I already have MFG Crosswind Pedals, TM Warthog and the DK2. For the seat and frame i'll be more than likely buying something custom but thats outside of this build's budget. The PC rig i already have is also roughly about $4000 with triple 980 GTX SLI. Also I could go a little higher than $2000 just for the platform. I just would hate to build a 2DOF and then realise that after all the effort into putting it together that I really want a 3DOF.

You may be in "good shape" considering what you already have.
With 2000.00 for the platform alone, you can do it...........and yes, 3dof does have advantages over a 2dof.

Knowing what I "do" know now.............3/4hp
Below is a couple gearheads that are good and reasonable.
http://www.automationdirect.com/adc...orm_Gearboxes_(Speed_Reducers)/WGA-50M-060-H1
http://www.automationdirect.com/adc...educers)/Right_Hand_Shaft_Output/WG-262-060-R

Thats very doable. So I like the cast iron one better from Ironhorse (2nd one listed) Is there a preference between cast iron vs aluminum ? In terms of motor, you mentioned a .75hp 3 phase motor with inverter. Is the inverter part of the motor or is that a separate component ? the function of an inverter is to change DC to AC correct ? So would that mean that I would have batteries going to the inverter and into the motor ? Wouldn't it be the same if I got DC Motors directly and skipped the inverter ?

Joe

Cast Iron is sturdier over time....
With the weight "loaded", I personally would not go less than 3/4hp.....and whatever you decide, you will have to match gearhead to your motors hp size. Inverter Duty Motors and Gearheads are a "separate" item,
UNLESS you fork out big bucks for a SEW Helical Gear combo..........just too expensive for my blood and they are not serviced in the US.

The VFD has many functions: 1. Converts Single Phase Input to Three Phase Output - which is what your motors will be...........plus, it will receive inputs/signals from your electronics board for motion and
speed - eg: forward-stop, reverse-stop, and how fast the sim will need to accomplish that speed. You will match your VFD to your motor size, input voltage, etc. Mine were about 135.00 each.

Tom

So going with this motor, gearbox, and vfd (I couldn't find a .75hp vfd, would 1hp work on .75 motors ?) does it look good enough you think for my usage ? and this is without a center spring assist correct ?

Thanks again,
Joe

Hi Joe,
Excellent choices - Same motor I'm using except mine are 1hp. Same VFD's that I am using.............and they are very very good.

I would suggest (as I would do it this way "knowing what I know now").......angle your motors/gearheads "in", like the Motion Video at top of this thread......you could still use a single lever vs. how they have
the dual arms and be fine................by angling in, you can move them closer and be "assured" of not requiring a support spring.....IMHO

Well, you now have a good plan on equipment/hardware..........so get physically busy friend........

Blessings,

Tom

Awesome, glad to have gotten your blessing on these parts, In terms of controller I see from your thread that you went with arduino/SMC3 route instead of JRK, any recommendation there ?

Joe,
With the motors / gearheads / VFD's you've chosen will give you satisfaction in your build.....just very good, reliable, equipment.......and strong!!

FYI - My absolute "weakest link" in knowledge is electronics........I understand wiring fine and can wire a home from scratch, but electronics and coding, a real dummy.

The folks here at the forum guided me on what I would need electronics wise: Two guru members here agreed on the UNO, as it would handle 3 motors, along with SMC3 firmware.
I have the UNO and firmware done and have statically set my pots...........

I am waiting on one guru member here to finish up my Opt-PCB boards that will attach to UNO for input and then output those required signals to the VFD's for movement.
I "should" have these in a couple of weeks as they are coming from another country.......

I do have my electronics "Box" finished, have all of my terminal strips, Contactor, 12V Power Supply (for Opt-PCB board power), VFD's wired with mains.............all is left is to
attach Uno and the two Opt-PCB boards, wire them up, and away I go........each Opt-PCB board will handle two motors, so in essence, I need two of those.

FYI - Very few members here have AC driven platforms - primarily due to the high cost, and many folks here feel that the AC platforms are not "fast enough" to replicate racing, but
are fine for flight. I will be doing both. IF my finished setup is "not fast enough" for my liking on racing, I can increase the frequency on the VFD's and just about get as harsh as
I want - and at 67 years of age, I cannot take the same pounding that the younger folks can take.......but it's all about "tricking the brain" into feeling the motion you see.........and again,
at my age, it doesn't take much to trick my brain into anything. I will finalize my finished build with the RTM Rift or Vive......whichever is the best suited for motion.

So, kind of an overview to see what you're dealing with................in summary, I am very satisfied with my build, the looks of it, the functionality of it......and I'm having a ball flying and racing
in my existing static setup - and can hardly wait to apply motion to it...

Tom

Hi Tom,

Thanks a ton for the info, in terms of the Opt-PCB Board would a Monster Moto Shield do the same job ? or are you requiring a custom one because it's AC instead of DC ?

Thanks!

Hello Joe,
I really can't answer if the Monster MotoShield would/could do the job??? Some guru here would have to answer the ?.
I know the Opt-PCB combines several boards together, plus has opto-isolation to clean up any erroneous signals from the AC....so, in essence, it is an "all-in-one" board, combined with the UNO.

FYI - for minimizing the erroneous signals, all of my wiring from the motors to the "electronics box" is inside flexible vinyl conduit / PLUS / I have the wiring (12/3 w/ground) all wrapped from motor
to termination inside the electronics box "wrapped with aluminum foil".....AND I am using shielded cable for the pots. Just wanted to make super sure I was doing it the very best way.

Tom

Thanks for the quick reply Tom, I've done some searches for Opt-PCB but can't find anything is that a model # or is there a specific brand attached to that product ?

Thanks,
Joe.

Joe,
From "all I can gather", they are a DIY board that requires etching etc.
There are other boards out there (on the other forum), but Thanos wants like 400.00 ea.......which is silly.
Attached is the diagram of what is being made for me. Don't have a clue yet as to cost, but I am sure they will be very reasonable, even with shipping from another country.
Maybe the diagram will help???

Tom

The diagram kind of helps as it describes the elements on the board but it doesn't include traces, Who was it that was building these for you ? perhaps I could order some as well ?

Thanks,
Joe.

Hi Joe,
First, I'll pm my friend here and see if I can get the traces for board......and I will ask his permission on him building more?? If he says it's ok, then I will pm you with his contact info.
Don't want to take anything for "granted" and poop in my nest.

Will be in touch with info.