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[Hdale85]

I've been searching around all night trying to see what some people have ended up spending on some of these 6DOF setups? I've done tons of DIY work, non in motion simulation but probably quite a bit of otherstuff that would probably apply to a lot of what goes into building a motion simulator.

Basically I'm wondering what it'll cost to build a 6DOF machine? Mainly looking for racing simulators and what not but very possible that I'll get into flight Sims as well in the near future. I have a wife and 2 young kids and she's not going to let me build more then one machine so I'd have to get what I want the first time

[Hdale85]

Are these anywhere near fast enough or tough enough weight wise when 6 of them are used? I'm guessing the payload is going to be something like what 2 of them can hold up by them selves?

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 1575wt_905

I'm guessing the actuators or motors are going to be one of the most expensive parts.

[Frakk]

There is a world of difference between a 6DOF platform and an other 6DOF platform.

Your cost will greatly depend on basically everything. Size, weight, payload, performance, the amount of work you can do vs. parts you have to get off the shelves, electronics for interfacing, actuators used, etc, etc.

Your price right now is anywhere between ~$4.000 - $the starlit sky. As I said, depends on what you want.

I don't think you can stop after your first platform, so you better sort that out with your wife!
If you build a 6DOF platform, it will technically never be done... There will always be improvements you will want to do to it...


edit: Those actuators will be way too slow (36"/min unloaded) and IMO way too week for fast movements. Although 6 of them will be quiet strong.

sirnoname is right, the actuators will be the least of your worries. They are only a very small (but very important) parts of the system.

[Hdale85]

So there aren't any DIY controller designs out there for a 6DOF setup?

And yes tweaks and mods are ok...but if it looks like I scrapped and built a completely new machine she may get upset...lol


Edit: More needs,

I don't think I'd need to support more then say 500lbs or so? I've been trying to search for actuators and what not... it seems you can get a lot of air cylinders for pretty cheap. Of course if there isn't a cost effective or DIY controller to be built for such a beast then really it wouldn't matter.

[Frakk]

You need very expensive air cylinders with very expensive valve control system to achieve fast and precise motion quality.
Hydraulics are the best, but they will run you into the $10.000 range only for the actuator system.

Your best bet is electric DC motor based actuators, since they are very cheap and there are a lot of drivers (h-bridges) available.
At the moment there is no ready to use DIY electronics available to control a hex platform, but you can put together more controllers for more actuators.

The problem comes when you have to control the positions of your 6 actuators in sync with each other, depending on the 6DOF position.
You can run the stewart algorithm (has to be custom tuned for your own geometry) in software, then output the calculated positions to each of your actuators.

For a quick example, here is a closed loop (positioning) DC motor controller: http://www.pololu.com/catalog/product/1393
You could use 6 of these, with 6 DC motor actuators like in your ebay link.
If you have the capabilities, you could consider building custom actuators that accept a variety of DC motors and screw shafts for flexible gearing.

After the actuators and interfacing is done, you will need a math plugin for the Profiler to take care of the geometrical calculations and make sure the actuators are not working against each other.

[Hdale85]

You mean like DC stepper motors or even servo motors like used in CNC machines?

And I didn't mean ready made DIY controllers but a PCB layout that I can etch and build. I've built lots of electronics.

[Hdale85]

http://www.drillspot.com/products/41331 ... r_Cylinder

These are some of the pneumatic cylinders I was looking at. At 75 bucks that's not horrible but the cylinder is probably going to be one of teh cheaper parts of the pneumatic setup.

[Frakk]

You are right about the cylinders, they are the probably the most inexpensive parts of the system. In the end a pneumatic system will have a much higher price/performance ratio than an electronic system. A $2000 electric will outperform a $10000 pneumatic setup.

Servo motors used in CNC machines are DC stepper motors in most cases. You could use those with stepper controllers, no problem.
You could even use CNC controllers if you manage to interface it with X-Sim. They are in fact a motion platforms, only on a smaller scale.

I was referring to brushed DC motors such as wiper motors, or basically any other...
If you look in the hardware section you will find the AMC and dMSHB if you want to make it on your own.

In my opinion it is not worth the time and money to build, for a little bit more you can get a professionally designed and manufactured full PID controller with current limiting, thermal / voltage / reverse battery protection, easy to use software package along with support and warranty.

[Hdale85]

Wiper motors are strong enough to lift several hundred pounds?

[Hdale85]

Are you talking about doing it like this?

http://www.youtube.com/watch?v=MxXEOcYY1M0

Also what would a 2DOF on top of a 6DOF look like? I see this mentioned quite a few times and some people seem to think it would be the best for racing sims?