Just getting started

Well I only have 1 thing driving my desire to learn arduino, and that's motion simulation.

I work as a game developer doing VR simulation stuff, from the software side, but have no experience with mechanical/electrical engineering whatsoever.

I sat down this past weekend and nailed down communicating with the arduino uno in real time from the game engine I use, I can turn a potentiometer and twist objects in game, or twist an object in game to rotate a servo arm at a 1 to 1 ratio (rotate airplane model 90 degrees and the servo arm rotates 90 degrees). Blew my mind.

Now to figure out how to scale the parts from my little micro servos to something that can move weight. I think I'll have to change my design to use linear actuators over servos.

After 5 posts, making a vid now.

I'm using the firmata example sketch only and can send commands from C#. The game engine (Unity 3d) also allows for easy UI creation to interact with the different pins.

Only have 1 servo, I ordered more yesterday and now waiting. Even stopped by radio shack on the way home hoping to find one but they didn't have any. Apparently the one I have only has 180 rotation not full 360.

Simple example:
In C# I just made a script that grabs the rotation (z axis) of the object it's attached to, clamps it to between 0 - 180 (because thats all my servo supports) and tells pin 9 the integer value in degrees.

Code:

void FixedUpdate(){ //Update gets called 30 - 60 times per second
            int num = Mathf.FloorToInt(transform.eulerAngles.z); //Make it an int
            num = Mathf.Clamp(num, 0, 180); //Only allow values 0 - 180
            arduino.analogWrite(pin, num); //turn servo
        }

There is a free "car race" tutorial from Unity game engine that gives you a track, car, and controls you can race around it with mouse/keyboard. You can build it as is. Might be interesting for some of you guys to be able to tie your simulator into your own game. Warning, it's addicting.

What is your budget?

DC motors can do the job:
- rotation like joyrider design
- translation Frex-like design (see below)



Nice achievement between Unity and Arduino

Budget depends on the design really.

Do you have any idea what motors these types of units use? Are those gear boxes on them? Do they cost $500, $1000, each, ballpark?


The thing I like about the motion platforms is the size, I could take this somewhere relatively easy and mount whatever type of chair to it.

I'd pay $5k+ if I could make something like this... (would hire a welding shop to make the frame/mounts)
Go to end of vid to see in action.




But reality is, I'd be plenty happy with a joyrider lol.. My original idea was to get a hammock and rock it in 2 directions.

Wouldn't let me post pics in last post with the vids:

I'd pay $5k+ for something like this... not sure what it would cost to fabricate at a welding shop, but I would pay $5k happily.
(attached pics, won't let me post them as links)

This one is using only 2 motors with a chain/belt to spin it. If the frame is balanced, I wonder how much power it would take...

Minimum $5k and the rest, in parts.
It would use powerful AC motors.

Yeah I'm starting to figure it's a bit too ambitious to go after 360 rotation without more like $15k. Looking around they cost like $30k min. I'll start with something simple.

My very first idea for a motion sim was to buy one of these chairs (image below) and rock it forward/back and left/right with a couple actuators.

Otherwise one of those motion platforms with 3 motors, what do you think it would cost for 3 motors that can move a platform with 300 - 500lbs?

would that be a 3 dof (2 dof with extra drift frame under it)
or 3 DOF with 3 motors lifting up?

Still thinking of designs. I finally received my servos I ordered last weekend when I got home today.

This is what I've prototyped so far this evening:



I wonder if I just recreated this design for human scale, 3 super beefy AC motors, can I get enough leverage to move a single person in the manner shown above? Then I just need 2 joints and 3 motors, whatever they cost. Or would a mix of linear actuator for tilting and servo for the rotation be best?

Hi, I love tinkering as well, but if you really want to build a sim that you can sit in, then unfortunately what you have does not scale up well at all without quite a few- $$$. Don't re-invent the wheel, there are plenty of low cost sim designs/software to look at/download on this site.

Yeah I'm looking around and learning. Just saw Bsft's thread on the 2 dof chair and it's absolutely perfect, doesn't take up a lot of space and cost effective. Thanks a lot for the parts list and such Bsft. http://www.xsimulator.net/community/marketplace/desk-racer-2-dof.91/

Also ordered a heart rate sensor and want to speed/slow a game's speed based on heart rate. So as your heart beats faster the global time scale increases so everything is in fast forward and ramp up visuals. Might be fun.

Well someone else is able to make the 3 motors spin exactly as my prototype:




Are those motors $10k each? More? Less?