2 step motors on one chipset

[lord051]

Hello,

first of all sorry for my bad English. I hope this is wright place for my post, if not, moderator please move my post to appropriate place.

I am doing one project, my vision is that something like this:

ImageShack Album - 3 images

So, one motor rotates the structure which has the 2 containers(for two colors) on it(all will be made of a light plastic, and balls also). That motor lead appropriate container under "glass", from that glass" will fall out the ball in container. That "glass" , from which are balls falin out, would be also made from plastic,it will have shape of a glass, with a movable bottom, there will be a second motor which will open and close bottom of the "glass", after he gets a signal from computer, it can be in shape of a plate, that makes a complete circle, and on that way it will open and close bottom. And on top of the "glass" would be a camera. I would put balls manually in "the glass, for that i would use side window in the "glass". Camera will shoot the ball, Matlab program will process that photo, and depending on the results, the signals would be sent to motors, one motor to open the bottom, and a second motor to bring a suitable container under "glass".

These are my two motors:

ImageShack Album - 3 images (i would use this one for open/close bottom)

ImageShack Album - 4 images (this motor to rotate containers)

Concept: I will put the ball in the "glass, the camera will take a photo, Matlab will process the image, when we get result, Matlab will send signals to the motor which manages the containers, means we bring a suitable container below the "glass", eg 10sec after we sent a signal to a motor which controls containers, Matlab will send signal to the motor that controls the mobile bottom of the "glass". Motor that controls the the movable bottom may for example make a complete circle, and so will be back again in starting position, ie open / close the bottom. Eg 10 seconds after Matlab sends a signal to start moving the bottom, Matlab will send a signal to the motor which manages containers to return to their initial positions. So, for now I have this vision, no matter that this will take a little longer, it is important to me this to work. I mentioned this time delays cause i need to be sure that previous process will complete before start of the following actions (it is possible all this to done without delays in a manner that the camera detects moving parts and Matlab controls them,
but it would complicate this too much for me).

I googled, and searched, so people advised me, and told me, that for this i can use step motors from an old printer. That they will do a job! Can they do what I need from them here?

Please tell me now how to connect motors with computer, so that they can be managed, and of course i have to be able to control them from Matlab. To be able to manage / control them with Matlab, I have to connect those motors chipset through the parallel port. I need to make a chipset, controller? I googled, searched, and I saw million scheme for such things, but which one would be the best / most effective? Is it better to work chipset for both motors individually or should i make a one chipset for both motors on it? I see that if i make a chipset for each motor individually, then i need 2 parallel ports, problem is i don't have any parallel ports, so I hope that there is a solution to make a chipset for both motors on it, I'll get a card for one parallel port. Please show me link / schemes that would be best for something like this.

A lot of questions. Only thing I could do to upgrade my project, is to make one more part for my project, which would bring balls automatically in "glass", from a special tank", and also i can put more containers for more ball colors, but that would further complicate the project, is it? I will be very pleased if i made it to work without those extra parts, and after i made it work without those parts, than i will think and find a solution how to add extra parts, and i hope i will do it!!

ufffff, a lot of text

All thoughts and advice are very welcome ...

thanks...

 

[Merlin3189]

Sorting machine

Your outline design sounds good to me. I like the way you have broken the solution into stages, which could be built and tested as modules.

-Parallel port sounds good to me. I have built projects controlled from a parallel port and they worked well. I think these days you can get USB to parallel port chips, but I've no experience of using them.
-If you have a PC without a parallel port, parallel port PCI cards are still available cheaply, so you can add one.
-Parallel port gives you 8 control wires, which should be plenty to control two motors.
-If you use stepper motors, I'd use two controllers for simplicity. I don't think they're very expensive these days (though I've no recent experience of using them.)
-Perhaps just using a simple DC motor to drive your disc would be ok. You would need then to sense when the disc reached the correct position: a simple microswitch (perhaps debounced) operated by a peg or notch in the disc would do Or an opto slotted switch.
-A parallel port also gives you 8 input wires to use for this.
-In theory maybe you don't need to sense the position using a stepper motor, but in practice they can slip (especially if the drive is belt & pulley or friction wheel) and you do need to sense their position at some point.
-Your diagram seems to show a the discs mounted directly on the motor. I'd think about using a reduction drive. That will give greater torque and also slow the rotation making it easier to get accurate positioning.

 

[lord051]

Thanks for advices. I managed to make my PCB, but at the end i used one motor, not two. If someone needs scheme for PCB contact me. I also programed code for controlling step motor in Matlab, if someone needs that, i will help.

Thank you...