Please help me planning my G-seat

[Bergison]

Hi everybody!

First of all I'd like to say 'thanks' for this great and informative site and forum! That's what I was looking for a long time, but somehow stumbled over it just a few days ago.

May I ask for your help in planning my project: I've built a flight simulator cockpit, mainly for DCS A-10C, but also some FSX, which I really enjoy 'flying' in:



However, up to now it is only a 'fixed base' sim, a fact i'd really like to change! I don't want to move it alltogether, what I'm planning to install is some sort of motion cueing like provided in G-Seats. Unfortunately my budget is too limited to just buy one, so I'd like to build it on my own, like the rest of the cockpit!

I'd like to be able to move two flaps on the seating surface and two in the backrest. It would be enough if each pair could move simultaneously, so I guess I'd need only two motors.

As the SCN5s are pretty expensive, I was wondering if wiper motors would suffice. What do you think?

What would you recommend using for the interface? Arduino with Sabertooth 2X12 is what sounds reasonable to me?

I am greatful for any suggestions, hints, comments! THANKS!

[vicpopo]

Hi Bergison,

Look at this video:


The wiper motors schown is to test a G-seat.I 'm trying to build the 2 another wipers motors for the complet seat.
2 wiper motors for the back , to wiper motors under my legs.

4 Wipers motors drived with arduino uno, h-bridges and with xpid firmware should work great.

You can have a look at many other sim with wipers motors.

And congratulations for your fantastic cockpit

These 4 wiper motors should be at least as good as gs4 ultraforce G-Seat ,for me no problem. You can after finished your g-seat build a 2 dof like on this video with also 2 wiper motors.total 6 wiper motors !!

[yokoyoko]

Hi and welcome to the forum,

first I have to say that no one I know has realised a motion seat like you are planning in diy (please correct me). But the idea is really good and I thought about it quiet some time ago, as I want to add this additional to my existing motion simulator (if time would not be so limited...) in the future.

I think you are looking for something like this? ---> http://i1.ytimg.com/vi/ZL0VwrPYH8c/mqdefault.jpg



If so, I would use a kirkey aluminium seat like this ---> http://www.racingplus.com/img/Large/Kirkey_Racing-Economy_Aluminum_Drag_Seat-16800_933.jpg
As they are made of aluminium rather than gfk it would be much easier to add the motors (servos) needed for the motion.

What motors you could use is a good question. Of course in some way wiper motors will be possible , i think. This would be the cheapest solution and they would be strong and fast enough. You would need 4 motors - two (l/r) under the seat and two (l/r) behind the seat. The seat will have to be "cutted" of course mounting brackets are needed.

If you want to stay close to the original you would need 8 big scale servos like these: http://rc-car-online.de/shop/de/products/y0750-y0750-orange-power-bigscale-ds24-5-digital-servo-1-st-.html -> just an example! (the first a found in google)
As these servos are not strong enough you will need two for every "moving paddle" in the seat.
This can become expensive. Here in germany this would be around 560€ for the 8 servos.


No matter what motor you choose - you will need a power supply and a 1-2 controller(s) (wiper + h-bridges). If you would go for wipers or dc motors here are plenty of good solutions around. For servos I think you could use the pololu servo controller (please correct me someone, I just guess).


The software part with x-sim would be no big problem, just 4 axis are needed where you can add your effects (forces).

I hope I could help you somehow - let me know what you think.


edit: damn vicpopo was faster.... loool

[Bergison]

Thanks vicopopo and yokoyoko for your advices!
I think i'll go for the wiper motors. What I'm not sure is how strong they should be. Do you think 10 Nm per motor is enough?
Another question: how many motor-controllers is one arduino able to handle?

[yokoyoko]

Hi,
I dont know which servos exactly are used in the gs4 seat but all "better" big scale servos i know have specs of around 250Ncm... even if you expect they have 300Ncm - the gs4 uses 2 servos per axis - this will give you around 6Nm per axis. 6Nm is a realistic torque you can get of a wiper motor.

At the moment a only know that the arduino can control two hbridges but vicpopo wrote

4 Wipers motors drived with arduino uno, h-bridges and with xpid firmware should work great.

Perhaps there is a change in development?

Edit.: otherwise you can ofcourse use 2 arduinos... they are very affordable

[vicpopo]

You're right yokoyoko!
4 wipers mean 2 Arduino uno and 4 h-bridges.
If i want to answer faster than you i didn't have time to write all détails!

[Bergison]

Hi and thanks again for your answers!

I got me used Volkswagen wiper motors (12V, 40W) yesterday from our local junk yard for 24 € (32 US$) each.

May I ask you one more question, before I start purchasing the electronics?

If I use "dual channel" motor controllers, like say this one:
http://www.elechouse.com/elechouse/index.php?main_page=product_info&products_id=2179

Do I still need two Arduinos to drive them? Sorry if this is a stupid question, but this stuff is completely new to me!

Oh, and another question: what power supply would you recommend to use for 5 of these motors?
Thanks for your help!

[yokoyoko]

There are no stupid questions. In the beginning this all could be quiet complex...

Yes you will need two arduinos. One for every dual channel hbridge.

From experience I would use around 20A per motor regarding the power supplies. With my wiper motors the stall current can get up to 18A per motor. Even if this is just a short peak...
Choose what you can get cheapest. I think 2x 12V 40A power supply + 1x 12V 20A but you will have to search a bit. Ebay is your friend - and china too

Some guys here use modded server psu's which are quiet cheap for the power but if have no experience with them.
An other option would be a car battery...

Why 5 motors? What is the fifth for?

Important!!! Before you start to test anything with your electronics please make sure all your wipers are "ground and potential" free while running. (You are from austria? Look in the german subforum for the thread to this topic) viewtopic.php?f=65&t=1185

[vicpopo]

Hi ,
You can put also a large car battery paralell to the psu.You can have always enough current for wipers.

For my project to test g-seat I though using an another solution instead wipers motors that is motors which lift up,and down the lateral car window .
I get some for free from my car repair guy because sometime the mechanic is broken but the motor is ok.
There is a problem in France often with Renault cars.I've got a small Renault car and the both electrical lift window right and left broken.
It' s an another possibily but until now not yet tested . Don't use this idea but it was just to give it on this topic.

[vicpopo]

Hi ,

A pic from both motors !

405689123.117527.jpg (939.46 KiB) Viewed 16360 times

Motors

I don't know how the car lift window powerfull is .