6 Replies Latest reply on Jan 9, 2015 2:43 PM by GaryDB

    NM Galileo project - Computer controlled watering system


      I'm making a water tower/sculpture. I need a controller board to:

      - charge a 12V battery from a solar cell (and stop charging when "full")

      - run a pump from the battery

      - turn off the pump when the tank is full

      - turn on a couple of valves to water plants

      - possibly include basic solar tracking using servos

      - A motor shield will probably be helpful


      In good Intel fashion, I've created project plan and schedule I'll post those next time.

        • 1. Re: NM Galileo project - Computer controlled watering system

          Project Objectives
          - pump water from our shallow well
          - water some grape vines on a schedule and with some moisture sensor feedback (eg. don't water after a rainstorm - something like this should work: https://communities.intel.com/thread/46190)
          - include it in a "sculpture" (safety note: the 50 gallon drum will weigh over 400 pounds when full of water) - see photo
          - use solar
          - use the Galileo controller (see block diagram)
          - I’m hoping to model my project somewhat after the Garduino project by Luke Iseman (http://makezine.com/projects/Garduino-Geek-Gardening/).

          - learn how to use Planet Blue blogging interface

          Stage 1
          - working pump controller, running off of solar
          - document the project on the Intel blogs
          - my goal is that the documentation would be nearly ready for an instructable or magazine article (à la Garduino)
          Stage 2
          - plumbing complete from well to storage tank
          - plumbing complete from tank to valve
          Stage 3
          - tank/tower installed over the well
          - solar panel/controller installed

          - first posts by Dec. 1, 2013 (done, but deleted?)
          - post progress and updates at least weekly (Sunday or Monday)
          - finish Stage 1 by WW03
          - finish Stages 2 and 3 by February (see the NMSU circular)

          - mostly use materials I have on-hand:
          - 12V solar panel
          - pump (LVM105 Amazon pump)
          - 32 ft. head
          - 14 psi
          - 280 gph = 4.7 gpm
          - 12V 6.5A

          • 2. Re: NM Galileo project - Computer controlled watering system

            Here's a photo of the water tower so far...


            And the block diagram of the project:



            I talked myself into buying turboCAD 2D to help with this and other projects. But now I'm on the learning curve for that too.

            • 3. Re: NM Galileo project - Computer controlled watering system

              The Galileo box plays the Intel jingle - how cool is that! 

              My first challenge - assemble the wall wart ;-) (See photo below)

              I also read this in the README file...

              Warning: You must use a power supply or you will damage the board! I guess it can't run off USB.


              The Arduino development environment went pretty smoothly...

              Mine installed as COM4
              6 minutes to upgrade the firmware?
              Upgrade trigger failure - read the FAQ
              unplug, then try it again - worked

              Examples-> Blink... Works!!! Hello World :-)

              That little chip runs hot!

              It's got an excellent datasheet with impressive specs.
              400MHz 32-bit Intel® Pentium instruction set architecture (ISA)-compatible processor
              10/100 Ethernet connector
              Full PCI Express* mini-card slot, with PCIe* 2.0 compliant features
              USB 2.0 Host connector
              USB Client connector, used for programming

              So far, it's been pretty simple to get started with the Galileo. I'll need to try a few more complicated programs.



              I spent this week researching the battery charging circuit.
              Arduino Peak Power Tracker Solar Charger
              at http://www.timnolan.com/index.php?page=arduino-ppt-solar-charger is awesome. But I don't think I need one that
              efficient for my project. Also, I want mine ot be simpler at first. If I find I'm wasting too much sunlight, I'll
              revisit this.

              After reading about charging lead acid batteries at the Battery University http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery,
              and using the Microchip PIC14C00 App Note (AN626). http://ww1.microchip.com/downloads/en/AppNotes/00626a.pdf I went for
              a simpler approach. I'm going to try using Lewis Lofflin's schematic at http://www.bristolwatch.com/solar_charger.htm.


              I ordered $20. of parts from Jameco. Cool.

              I'll be using an LM7805C for my 12V->5V supply since I have one.

              • 4. Re: NM Galileo project - Computer controlled watering system

                I made some progress this weekend. My Jameco order came in so I go out my breadboards and went crazy.

                I seem to be able to read all the voltages so far, but I haven't tried to turn on or off the transistors.

                I measured the voltage out of the solar panel and read it into the Galialeo, I can also read the

                battery voltage. I needed more MS Excel experience so I figured out how to calculate the line

                using Excel. It was pretty easy but I hadn't done it before so it was good experience.

                Here's the spreadsheet/line equation for my solar voltage. I needed that to display the

                voltage in the Arduino serial window. I tested by moving my desk lamp closer to or farther from the




                I still need to check the current drain of the Galileo and also see if I can turn on and
                off the voltage at the battery. Here's the circuit so far (with the code used to read/print voltages).


                /* Solar cell battery charger/regulator
                All this does is read the voltage at solar cell (A0) and
                The battery voltage (A1). It blinks the LED to show that
                it's looping - in case the serial didn't work ;-)
                #define voltage_in 0
                #define voltage_out 1
                #define charge_enable 11

                int x;
                int y;
                // Pin 13 has an LED connected on most Arduino boards.
                // give it a name:
                int led = 13;

                int chon = 5000; // charge on time
                int choff = 2000; // charge off time

                void setup() {
                    Serial.begin(9600); // opens serial port, sets data rate to 9600 bps
                    // initialize the digital pin as an output.
                    pinMode(led, OUTPUT);
                    //digitalWrite(charge_enable, LOW);

                void loop()   {
                  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
                  //delay(1000);               // wait for a second
                  x = analogRead(voltage_in); // voltage from solar panel
                  y = analogRead(voltage_out); // voltage on battery

                  Serial.print("Solar A/D count is: ");
                  Serial.print(". Which is about this many volts: ");
                  Serial.println((x * .0579) + .6249);

                  Serial.print("Battery A/D is: ");
                  Serial.print(". Which is about this many volts: ");
                  Serial.println((y * .0579) + .6249);

                  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW

                • 5. Re: NM Galileo project - Computer controlled watering system

                  I finally got to work on this a little more. I'm doing some testing. Here's my test setup. In the spirit of good jury-rigging, it's duct- taped to a cardboard box ;-)


                  The battery is in the upright box...


                  Since the Galileo uses about 1/2 amp, I decided to only run it when the sun is out. I'll put a relay in line with the solar to turn on the 5V power only when solar voltage > 12V.  That should be enough to run the Galileo with some left over to charge the battery. There's lots of questions with this, but it will allow me to move forward with the project.

                  • 6. Re: NM Galileo project - Computer controlled watering system

                    Really Nice project, I was looking into doing something similar with rainwater storage. Did you ever complete the project? Still Ongoing? Any updates / Obstacles?