Right now i am using 6A and it works well. however, i will put separate DC supplier to each module (each 4 actuators).

the stage now is to connect them first to the computer, but no idea yet exactly how. 

I have 8 actuators
http://www.ebay.com/itm/Multi-function-Linear-Actuator-Motor-DC12V-150mm-Stroke-Heavy-Duty-500N-HG-/121910665213?hash=item1c62711ffd

The DC power strong enough for all the 8 together.

What is the ULN2003 ?

There is no use for it... It's just an ProtoType.

What else can i use?

i guess this one is good
http://denkovi.com/usb-16-relay-board

Yes. i using 6AMp  dc so simple switch will not work.

maybe something like this

The pistons works with DC, up - when + connected to + and - to -, and down when the opposite, so i think need 24 switchers to control, but i am not sure. 

Anyway i still looking for somebody that wants a bit work...

I am not sure that 16 is enough but i don't have any experience. right now every switch have 6 connections so it is 48, but i guess it can be done also with 16

Right now i have 8 switch with up/down/neutral.

I am doing it as prototype for my patent.

Check the YouTube up

 

Thank you very much.
I guess the code will be on the PC and i will buy all the hardware that needed.

Until now i finished only the hardware and the base electronics.

Hi every body, sorry for writing in English, my Greek is pretty bad.

I am building now prototype for my robotic modular arm, https://www.youtube.com/watch?v=kesImjNqyN0

I finished to build it and its work now manually with up-down switch for each piston. I would like to connect it now to computer and i need a student to help me with this.

(i will pay of course the expenses and some small amount for every work hour)
So, if somebody interesting, please let me know.

(my place is in Ippokratio)

I am available in the email, skype (elisom) or on mobile 6948036444

Thanks a lot
Eli