Main > Main Forum

Complicated Diversions (Rotating Monitor, Yes or No)

<< < (6/9) > >>

DaOld Man:
If you want to use pushbuttons, such as Happ, the circuit gets a little more complicated.
Here is a drawing showing the happs PB's.
You will need to change CWR and CCWR to 5PDT relays.
When clockwise PB is pressed, the N.O. CWR contact closes, and seals around the pushbutton. If you release the pushbutton, the relay stays on until the limit CWLS opens.
The N.C. CCWR relay contact is an interlock. That way you cant turn both relays on at same time by pressing both buttons.
If CWR is on, the circuit to CCWR is broken, and vice versa for CCWR.
The circuit for CCWR is basically same as the above.

DaOld Man:
The switch circuits could also be replaced with a small programmable logic controller (PLC) called a "nutchip".
But I dont see much mention of using PLC's in this board.
What is a nutchip you might ask?
A nutchip is the brand name of a small integrated circuit that has 4 digital inputs and 4 digital outputs. One of the inputs can be used as an analog input.
The chip can be programmed to do a variety of things.
You write the program on your pc, download it to the nutchip via the serial port and you have a PLC that doesnt have to be hooked to the computer to work.
Want to learn more?
Check out:
http://www.nutchip.com/
And no, this is not a joke, and also no, I do not make anything off selling the nutchip or referring anyone to it.
I bought two of these to play around with, and I can see where they could come in handy for robotics or alarm systems, or to just learn about PLC's.
But who knows? With the minds we have on this board, Im sure we could use it on an arcade cab!

Cornchip:
 Wow...that Nutchip has some possibilities. I was doing some reading on the website and noticed that 'timeouts' are used for various things like making a LED blink etc. Could that also be used to control a relay and vary motor speed (over coming motor RPM that might be too fast instead of gearing). Also using a single illuminated Happs push button and using an input to cause the button to flash while moving the monitor.

 Cornchip.

DaOld Man:

--- Quote from: Cornchip on October 18, 2007, 08:52:02 pm --- Wow...that Nutchip has some possibilities. I was doing some reading on the website and noticed that 'timeouts' are used for various things like making a LED blink etc. Could that also be used to control a relay and vary motor speed (over coming motor RPM that might be too fast instead of gearing). Also using a single illuminated Happs push button and using an input to cause the button to flash while moving the monitor.

 Cornchip.

--- End quote ---

Controlling motor speed as you mention is called Pulse Width Modulation (PWM).
DC drives use it to vary the time the current is on and how many times per second it is on, thus controlling the speed of a motor.
This is impracticable with a relay, due to the contacts of the relay arcing, and though it may work for a while, it wouldnt be long until the relay failed. Plus the noise (electrical) would be tremendous.
You could use solid state transistors instead of relays (this is commonly called a "H bridge"), and possibly pulse it with the nutchip to vary motor speed, I havent tried that so I dont know if it can be done, but it does seem feasible.
On the nutchip site they show an example of controlling a servo motor, so I think it is possible to PWM a H bridge.
As far as making the button light flash with the nutchip while motor is turning, yes this would be quite easy.

Here is a diagram of how the nutchip would hook up to my first motor controller.
Note that transistors have to be used to switch the relays (Q1 & Q2), because the nutchip's power output is limited.
Also, I think the nutchip needs 5 volts, so a 5vdc regulator will have to be used. (not shown).
You could program the nutchip to turn on appropriate direction when a button was pressed. The button's LED would flash until monitor reached end position, then remain solid on, or turn off, or remain on for a few seconds then turn off. The program could be easily changed, that is what makes PLC's so great.
I think I will use this on my monitor rotation.

csa3d:

--- Quote from: Cornchip on October 18, 2007, 08:52:02 pm --- Wow...that Nutchip has some possibilities. I was doing some reading on the website and noticed that 'timeouts' are used for various things like making a LED blink etc. Could that also be used to control a relay and vary motor speed (over coming motor RPM that might be too fast instead of gearing). Also using a single illuminated Happs push button and using an input to cause the button to flash while moving the monitor.

 Cornchip.

--- End quote ---

Just to throw this out to all the budding hardware developers, I'd pay for an out of the box solution to rotate a VESA LCD mount.  Seems like there are enough people who've switched over to LCD technologies lately that this might be something to look into.  This solution would contain hardware and software in a professional package equivalent to Randy's E-Ice campain in my ideal world.

Navigation

[0] Message Index

[#] Next page

[*] Previous page

Go to full version