Society of Robots - Robot Forum

Software => Software => Topic started by: hassanjaved on March 30, 2006, 10:04:31 AM

Title: Controlling machines with computer!
Post by: hassanjaved on March 30, 2006, 10:04:31 AM
Hi!How can we controll motors and other stuff by using computer through the serial ports.If so,then can we design the software to control that motor or any other device in visual basic.net.

Please notify me with any links related to the above question.
                                                              thanks.
Title: Re: Controlling machines with computer!
Post by: Admin on March 30, 2006, 02:55:46 PM
For controlling DC motors:
http://www.societyofrobots.com/schematics_h-bridgedes.shtml

For controlling servos:
http://www.societyofrobots.com/actuators_servos.shtml

Serial port info:
http://www.infonewsindia.com/pinout/

Basically all you do is write a program that causes your computer to send out a signal to your serial port. Then connect that pin outputting the signal as the control line of your circuitry, as described in those links.

A few years ago I made an LED blink from my serial port with a program written in C. You just connect a resistor (to limit current!!!!!) to a pin in your serial port. Then an LED to the resistor. And finally attach the other end of the LED to the ground pin on your serial port.

Just be careful to not apply a voltage or allow more than a few mA of current to pass to your serial port. If you do, its bad ju ju for your computer making it do bad fire like things . . . .
Title: Re: Controlling machines with computer!
Post by: 2Hektik on April 06, 2006, 08:29:16 AM
Yes, all electronics actually run on smoke... that's why its bas when you let it out!
  :P
A fairly cheap option for stuff like this is the National Instruments USB-6008 DAQ card. I think the site is www.ni.com. Comes with a free student copy of LabView too.
I'm almost certain it has 8 outputs and inputs for both analogue and digital.

You can read the inputs from Labview, interperet them with a labview program (very simple, good for learning) and create your own output...
Title: Re: Controlling machines with computer!
Post by: Admin on April 06, 2006, 09:06:24 AM
Thats the link:
http://www.ni.com/dataacquisition/

I used DAQ input only hardware from another company, complete with labview, but it was only able to take 10 readings per second - sucky speed for robots.

 . . . so make sure it can run at the frequency you want . . .
Title: Re: Controlling machines with computer!
Post by: 2Hektik on April 06, 2006, 10:13:27 PM
The USB-6008 will give you a digital input sampling resolution of 5MHz which should be plenty.
Title: Re: Controlling machines with computer!
Post by: roschler on November 08, 2006, 07:22:38 PM
I like the Robix controller but it's USB based, not serial port based.  The advantage to this of course is that it doesn't require external power because USB ports provides power.  You can control a ton of servos and it does have some I/O ports too.  But the best part is that it has a client/server architecture.  In other words, you could have the client software executing your commands and scripts, while the server software talks to the controller and controls the robot or gathers I/O.  Since it's IP based, the server could be on a computer downstairs or anywhere across the Internet.  The client/server communication is all handled for you.  You need to write in Java to use it.

Robert.