Hmm.. have to make some base work so that you take interest
Been watching the 'Graphical Fountains' on Youtube...
[nomedia="http://www.youtube.com/watch?v=mFD__5FyXVY"]YouTube - Japanese Creativity - Water Fountain[/nomedia]
[nomedia="http://www.youtube.com/watch?v=tnPnwET4x9k"]YouTube - 3dx scenic studio's new graphical water display[/nomedia]
I am thinking to make a similar version... I know its a heck of work but also know that everything is possible with collective efforts and team work...
just want to get ideas from you, what you think how this thing work?..Do we need lot of solenoid valves with lot of tiny steppers?
Programming ?..do we need to make our own programming software?.. just think if we get the image and convert it into bits and bytes and send to the fountain?...
I will try to use PIC or AVR microcontroller with multeplexing, have to programm a software in VisualBasic , make some initial hardware.. Just thinking of 10 rows of fountain for the time being...
Any ideas from you guys?.. this may be our 2011 PROJECT..
Hmm.. have to make some base work so that you take interest
I would start by using a pic coded with C. I really like the dspic series.
'Pixels' are determined by distance in the x direction and time in the
So, some number crunching is in order first.
Suppose that that fountain is 128 'pixels' wide.
Guessing the time per pixel is a bit harder. There appeared to be
minimal pressure at the nozzles - I would be tempted to use an open
reservoir at the top with a row of valves. Time resolution of 10 mS
ought to be plenty. So image data requires 1600 bytes per second -
not really a whole lot. However, all valves need to be synchronized.
The electronics would be very similar to the Spoke Persistence of Vision
project. The 74LS595 chip looks ideal for this.
However, I'd would probably want a PC chucking image data out a USB
port to a suitable microcontroller which then fires it out the serial channel
to the latches and triggers the sync. Perhaps some buffering would occur
in the microcontroller so that PC timing becomes less critical.
Last edited by vegipete; 02-18-2011 at 04:38 PM. Reason: Woops, data rate out by an order of magnitude.
Thanks vegipete for insight
Offcourse, we are thinking on the same pattern .. Use of Shift registers (SIPO) and Image converting software into bits of rows.
Here is my scheme and current work so far:
1- Programming a Image (Bitmap) software. This software will convert the image into Black and White. The White will be '0' bits whereas the Black will be'1' bits.
2- Making a structure having a top with open reservoir Just atmospheric pressure) , on which we will install Solenoid operated valves. Lets suppose 16 valves at the top in a row.
3- Considering 16 SOV, we will make the software to generate image of 2-bytes in a row. Each bit will be considered as ON or OFF.
4- The Hardware will include PIC microcontroller that will take the data from the Image software for each row (2 bytes)thru SERIAL PORT (USB)throw the data to the shift registers that will decide which valve will be ON and which Valve will be OFF...
5- The timing can be adjusted in the image software
1- I am searching of Solenoid valves (24V DC).
2- Writing a software (Image mapping) in Visual Basic.
In the attach image (just a rough skecth), Each row the black shows the solenoid valve is open whereas the white shows the solenoid valve is closed.
Markwind, nice idea and can be implementable with some limitations..
1- Timing issues, Here we are dealing with Water and gravity and the timing between each row of water drops is very critical.
2- We will be limited to scrolling of programmable words only.
3- We will be limited to very few solenoid valves (10 or 15) considering the no. of rows of the sign. (No. of Rows of sign= Solenoid Valves). So very less resolution.
yesterday i purchased a lot of 24VDC solenoid valves from scrap shop. I got 0.8 US Dollar each. Their were only 15 available with the shop so i purchased all of them. They told me that on monday they can supply more of them. So with less than 10 US Dollar i got 15 Solenoid Valves.
They also available only solenoid with Stem plugs, 12VDC and i purchased one brand new for the same price.
Now i am thinking two things:
1- Controlling of those solenoid valves with AVR microcontroller i.e. Arduino
2- Controlling the Solenoid with PIC Microcontroller i.e. 18F4500 that can handle USB interface easily.
Using Arduino is simple as it contains USB interface and can take serial data from/to computer, but salvaging the complete Arduino for this project is not cheap. The PIC interface will be quite simple and cheap only if i know how to interface the computer with PIC thru USB.The only problem is interfacing USB with PIC that i do not know how to do it.
Last edited by Khalid; 02-20-2011 at 01:18 AM.
Get a big dot matrix printer. The printer head has numerous tiny solenoids that drive the individual printing wires and each solenoid is powered by a conductor in the ribbon cable running to the print head. Wire these individual conductors to your little solenoid valves and the printer would print in drops not dots.
You might need to connect the solenoid valves through little power transsitors with the printer signal triggering the transistor so you have enough current available to drive the solenoid valve.
Probably regular solenoid valves will not respond fast enough to give nice drops without any dribbles. What would be needed are valves like those used for fuel injection where there is a little needle that opens and closes right at the orifice. This starts and stops the flow very quickly and precisely.
An open mind is a virtue...so long as all the common sense has not leaked out.
Here the pictures of solenoids
Geof, that is another good idea I often amazed how peoples brings different solutions for one problem ..Getting the Dot Matrix printer and hacking it for this purpose will require some skills that a person talented like you have or RomanLini or Russell AKA epineh...but again your idea is Out-of-the-Box and workable...We will definetly think on that...
In the above post, i have attached the pictures of the solenoid valves, the solenoid ON/OFF by applying 24VDC but still to be tested with water.
I currently working on PCB circuit interfacing the PIC with USB... and this interface is hard part for me.. The programming, interfacing and mechanics seems very easy.... Keep in touch...
I just stumbled on this thread an it looks like an interesting project Khalid !
Back when I was a boy and used to play with very low power PC's (C64) to make any kind of graphics at a reasonable speed I was setting up a background of sorts, then pointing the screen map area to different locations, this had the effect of a scrolling background with very little cpu load, but worked OK I guess.
You could do the same with a micro easily enough, but it should be able to shift the image as a series of bits, shifted from some kind of bitmap stored in memory, if you made it a series of 8 bit chunks to form whatever size "line" you need any kind of micro should be able to fire/stop the solenoids fast enough to keep the lines horizontal.
The biggest hurdle I see is getting/making a suitable solenoid, it needs to be able to output "pixel" sized drops fast and without any dripping, not too sure about that, will sleep on it.
Should be interesting to see what comes out of this