Frex Type Pneumatic Sim - questions and ideas

Hi All

Great forum, great advice, great looking software! I have a couple of questions for you guys.

Firstly, Why cant I download the software? I've tried about 15 times on two different computers, on two different networks, and it just downloads to about 2.5 meg, then stops?

Im ready to purchase all my parts for the pneumatic option. Someone has offered me two cylinders 40mm bore/ 80mm stroke at a very good price, should I go for them or you think they are too small a stroke?

I wanted to use a ball joint from a truck or something for the centre attachment of the seat, something like this:
http://www.innerauto.com/images/partIma ... joint1.jpg

think its a good idea? Or must I source on of those rubber mounts?

What is the best interface to use to control my solenoid valves out of all the ones mentioned on this site, and does it suppport softmotion (the conrad electronic 8 relay serial board looks best to me)?

How many people have successfully made a working motion platform so far using this software and pneumatics?

Do you think Simforce GT will be cheaper or more expensive to build than a pneumatic version? Should I wait before doing the pneumatics and just build a stepper motor version?

Sorry for all questions, but just want to be sure before I buy everything. Thanks very much once again, and if there is anything I can do to help out, let me know.

Hi

Wellcome to our forum!

I have no idea!?? But I emailed it to you.

Generally. The thinner they are, the faster they get. I think 40/80 cylinders will fit. Frex has 100mm stroke, but if you get the 80mm ones cheap, then grab them.

Hmm, I'd prefer a rubber mount. But as the pneumatics dont make such vibrations like the steppers, perhaps the balljoint will do it as well.

Are they 12V or 24V?

Less than 10. But as the software, and big parts of the X-Sim homepage, are translated to english now, I think more people will start their motion platform with X-Sim.
Feel yourself as a pioneer

The pneumatic setup will be cheaper. For sure.

You cannot be sure. Let me explain. A Frex Simulator is plug'n'play. A solution with the X-Sim software isnt as easy. Its more like experimenting. You would need some time to do the configuaration, make movement profiles and fine-tune the system.
But we would help you.

We'd need need some Simulator CAD drawings

regards
ego

Thanks for sending me the software.

Dont worry, I understand that X-sim is not plug and play, I have a pretty good understanding of how it all works... In the beginning I was concerned whether or not Xsim can hold a cylinder in the middle of its stroke, and return there automatically when there is no g-force.... Now that I see Xsim accomodates this, it all seems fairly straightforward, but I'm sure I will experience a few hiccups along the way.

I think I will get the 40x80 cylinders, the price is very good. Even if I just use for initial testing, I can upgrade at a later stage, possibly to steppers.

I have not bought the valves as yet... what should I get, 12/24v? Can I use an old 300w pc power supply somehow?

Thanks!

ps. I have never used CAD before, but I can make fairly cool photoshop technical drawings (2d)...?

Valves

Hi Franknstein,

12VDC or 24VDC doesn't really matter!. 24VDC is more commonstock!.
Therefore i bought the 24VDC SMC valves.

If you build the Velleman way. VM110 controllerboard be sure to use the VM129 relaisboard!. (i'm not sure the VM110 can handle the 24VDC current of the valves).

Soon i'll try to post some pictures of my electronic setup!

later!.

Cool, I will get the VM129 then, but does it support the softmotion function? Also seems that the VM129 is not a USB card, how does it interface to the computer? It also seems its a 12vAC in and 12vDC out... is this correct?

You'll need the VM129 aka K8056 relaycard additionally to the VM110 aka K8055 usb interface.

The VM110 is the mainboard. The VM129 has to be conncted between the VM110 and your valves because the VM110 cannot provide enough power for the valves.

Please wait for Renoboss's sketch/pics.

You should consider that relays are a little bit noisy (additional to your valves) and the reaction time will be higher. So you will get a small delay at each command (signal switch high/low). But I'm not sure if you will recognize it while working.

Chris

This is the Velleman VM110/129 combination.



I'm workin on a transistor card layout right now. But if you cannot wait, try the setup above

regards

Thanks for the drawing!

Is this really the best option? Becuase here I need to use two interface cards and four pneumatic valves, compared to some of the other options on this site, where you only need two valves and one card? What would be a fairly well priced method, that works well?

EDIT: I see on this page:
http://www.x-simulator.de/de/hardware/c ... leman.html

Is the four pneumatic valves to use the softmotion system? So I can use just two, but then I wont have softmotion right?

Also, why on the drawings on that page are you not using the velleman 129, only the 110?

Sorry for so many questions, but what is a 'SEATBELT SPANNER' and how does this work?

@illi

It works well in your setup without relaycard. Well, you're a lucky guy.

But afaik some other members complained about problems in pulsmode, because the VM110 cannot provide the valves with enough power.
Perhaps your setup works without relaycard, is because you dont use the pulsmode.

@Franknstein

The pulsmode is way better compared to the normal single speed mode. But the best solution is a setup with 4 valves without pulsspeed.

The trick is, instead of pulsing the pressure, each axis gets two pressure connections. One for slow, one for normal, and if you combine both you get fast speed. Thats way smoother than the pulsmode. Do you understand?

Its right. There is a VM110 single setup shown on the page. But its safer to use a relaycard additionally. At least, if you want to drive in pulsmode.

But as a relaycard slows down the response time, I am in train to work out a DIY transistor-card. Without SMD parts
It will be much easier to assemble than the RnR 1.3 interface, and could be connected to the Velleman instead of the VM129.

Imho, you should build up a 4 valves (5/3 middle closed) system

regards

Ok I understand perfectly, I will see if I can do the proper 3 speed setup. How long before you think your new transistor card design will be ready?

Also, what is the seatbelt cylinder for?

Thanks again!

The layout for the transistor card will be ready within the next 2 or 3 days. Working on it right now.


Sorry. I've forgotten the seatbelt question. You could attach a pneumatic cylinder to your seatbelt. Its a seatbelt tightener.

Great thankyou, understood.

What items to I need to regulate air pressure on the two Slow valves? I Am guessing I need 1 main air regulator for +- 3bar (normal just goes to two valves), and 1 more set at +- 1bar (slow - just goes to other two valves). At fast speed its 4bar.... is this correct? What is the item number for Festo regulators... any idea?

tnx

This is correct. What illi tries to tell you, is that you cannot add the power of 3bar and 1bar to the power of 4bar, because the force isnt proportional.
But you have understood the principle

@illi

Anyway, thanks alot for your help!

Gruss
ego

Ok, so basically the valves have adjustments on the exhausts already? So the entire circuit is maintained at a set pressure and each valves exhaust is set differently to get your 'slow' and 'normal'?

Yes, I understand now that pressure is not proportional, its exponential, that makes sense. Thanks for the explanation iLLi.

Another question, can I make a small silent air compressor from an old fridge or aiconditioning compressor and small gas bottle? Will this sort of compressor be quick enough to supply 3 bar to this kind of system?

tnx

No, just the expensive ones Maybe its cheaper to connect some regulators like illi posted above, instead of buying valves with integrated regulators.

If you buy valves, watch out for 5/3 valves with middle position closed. The respond time should be under 20ms for opening the valve.
Brands are SMC, Festo, and some other. I think you could get cheaper ones from other brands.

Thank ego. ANy idea where to get the 5/3 valves cheap? I am struggling, people here want R1500 for one, which is about 150 Euro each, so thats 600 Euro for 4. It seems very expensive, but I see one FEsto one on Ebay for $25 which is cheap (but its centre open).

Here is someone in my country trying to sell me this, but I dont think its suitable... I think I would need 8 of these:

http://www.bidorbuy.co.za/jsp/item/Item ... Id=4134793

THanks again.
R

Bump?

I cannot tell you if the valves, in the link you have posted, are good or not as no specs are named. But as they arent 5/3, you could use them only for puls-mode.

Besides 5/3 and middle closed the response time for opening and closing the valve is important as well.

just to compare. The festo's have

open=12ms
close=25ms

response time.

Watch out for norgren, smc and other brands as well.

The transitor board is almost ready. You dont need to buy the relaycard. You'll just need the vellenman VM110.