Parts
This page is here to serve as a guide to locating the various parts you will need for this project. Some parts you will be able to locate at a local hardware store (or similar). Other parts will have to be ordered online. There are some brief descriptions of things of note, and there is a price sheet just to give you a rough estimate.
This page also features basic explanations of some of the kinds of parts you will be working with. If you are new to any of these concepts, please be aware that the information I provide on parts here is very superficial and general. There is a wealth of information out there online and through your local hacker clubs about some of the basics covered here.
- GardenBot software package
- Arduino
- Heat-shrink
- Soldering
- Bread-boards and Proto-boards
- Junction box or wire connectors
- Power supplies
- List of parts and prices
The GardenBot software package is currently not supported. You can download the exsiting version here, but it is very buggy -- appologies in advance.
Download the old package - (2011-01-13)
Arduino is an open-source microcontroller. The short
explanation is
that Arduino is a little computer that is designed to make it easy to
hook up various devices for inventing new kinds of interfaces. Arduino is used as the brain of the GardenBot system. If you are not familiar with the Arduino platform, you will need to start by going to...
The official Arduino website
You will want to start with the "Getting Started" link at the top. And proceed to the "Learning" page when you are ready to start building some simple projects.
You don't need to wait to be a Jedi master to start your GardenBot project. Just make sure you are comfortable with uploading code to your Arduino board, and that you have a rough understanding of the different pins on the board -- for instance digital vs. analog.
Heat shrink tubing is very useful, especially when you are trying to integrate electronics into dirty environmetns like the garden. It gives you a cheap and easy way to water-proof your electrical connections.
Heat-shrink is a type of plastic tubing that shrinks to half it's diameter when you heat it up with a heat gun -- so, yes you will need a heat-gun. For many of the projects on this site, we'll be using a variety of heat-shrink that is lined with a thin layer of glue (the same type as a hot-glue gun). When you heat the tubing up, the glue will seal around electrical components creating a water-proof seal.
Heat-shrink shrinks down to about half its original diameter. You will probably want to practice a with a small piece first so you can see just how much it shrinks (it's not a lot). When you want to seal an electrical component / connection, select a piece of tubing that is only as big (in diameter) as it needs to be to fit over the component. That way when the tubing shrinks, it will form a nice, tight seal. If the diameter of the tubing you select is too big, it will buckle and warp as it shrinks creating air pockets and holes for water to get in -- not good.
Remember that you will want to leave some extra length on either end since the tubing shrinks in all directions.
If you have not done much soldering, you will want to get practicing on anything as soon as you can. Soldering is really kind of an art -- you have to get the knack of it.
There is really only one concept you need to know. The essence of good soldering is that you DO NOT melt the solder with the tip of the soldering iron. You must use the iron to heat the piece you want to solder. And then the piece will get hot enough to melt the solder onto itself.
If you do it this way, your solder joints will look clean (don't worry, you'll get better eventually). If you do not do it this way, you will end up with what we call "cold welds" -- lumpy mounds of solder that seem to avoid the piece you want it to stick to.
There are many good resources online for learning how to solder -- with illustrations and everything. The main thing is that you start getting your hands dirty.
When you want to put your parts together and make a circuit board, you'll want to start with a bread-board, and then move everything to a proto-board.
This is a bread board. It's purpose is for you to
rough everything out before you commit to soldering things down. You
can stick components in, pull them out, and move them around until you
get a circuit that won't be changing any more.And this is a proto board. On the proto-board, you must solder all the components down. This means that you are past the bread-board stage, and are ready to have a permanent circuit.
There are a lot of places in this project where you will need to connect wires in a way that will allow you to disconnect and reconnect, etc. etc... For this, I like to use little junction boxes.
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To start, you will need the small proto-board and the screw terminals. |
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Now, you just
solder the screw terminals to the proto-board -- being sure NOT to
connect any of the terminal posts to each other (unless you mean to). |
There are many other ways to connect wires. Feel free to use whatever makes you comfortable -- like wire screw-caps, etc.
There are a bunch of options when it comes to power.
The Arduino board provides a basic 5v, regulated power supply. There is a standard barrel-jack plug that allows you to you a range of wall-warts (see below). However, you may not want to rely on this if you need to power heavier load devices like motors, or if you are getting noise in your sensor readings.
Wall-warts
A wall-wart is a cheap power supply used by the various electronics in your home. It is that little box that you plug into the wall outlet that then has a thinner cable that you connect to your device. The nice thing is that you can use this wall-wart to power the Arduino board or the free-standing voltage regulator (see the brain module).
If you shop your local thrift store, it's very likely you will be able to find a good selection of wall-warts (usually $1 or less). The important thing is that you find one that has specs that work with the voltage regulator on the Arduino board -- 6 to 12 volts DC, plug tip polarity positive. And be sure to check that the jack is the right diameter (you might want to bring a board with you).
ATX power supplies
The ATX power supply is definitely optional. It is mentioned here because there are water valves and other garden devices that need a specific voltages. The ATX supply can power many devices simultaneously without power loss, so it may be worth learning about if you have devices that require voltages other than the Arduino's 5v.
If you've ever taken apart a desktop PC, then you have seen that metal box where you plug the power in. This is call an ATX power supply (or just PC power supply). You can sometimes find these at thrift stores as well, or if you have a good local recycling center and they accept computer waste, then you might acquire one that way.
These supplies are a little more complicated to hook up, but they provide many different voltages and so they are quite useful if you need to power various devices. There are tutorials online explaining how to convert an ATX supply so you can use it as a bench-top power supply.
Please note that some of these parts are optional -- in the sense that your particular build may vary.
I just wanna say off the bat that I shamelessly endorse SparkFun electronics. They have selection, good prices, and they use brown-paper for packing (I hate styrofoam peanuts and extra plastic bags).
note:
All prices in this list are based on what I spent in US dollars in 2010 to aquire them. This list is intended to be a rough guide only in helping you estimate the cost of your garden automation project. This list in no way guarantees that any of the items listed will be available for the price listed.
| Part Name | Where I bought it |
| Arduino board (brain) | SparkFun |
| LM335 temperature sensor | SparkFun |
| small photocell | SparkFun |
| resistors (various values) | if you don't already have a collection, you can buy a kit of resistors from SparkFun |
| proto board - 1 in | SparkFun |
| proto board - 2 in | SparkFun |
| galvanized utility wire, 12 gauge | my local hardware store |
| glue-lined heat-shrink tubing (various sizes) | Buy Heat Shrink |
| electric solenoid water valve (24v DC, 5/8" ID) |
I used Orbit brand valve from Amazon. But can be bought at home garden store |
| 5/8in ID hose |
my local hardware store |
| threaded hose ends (often called
"hose repair kit") |
my local hardware store |
| metal hose clamps (screw
adjustable) to fit over 5/8in hose |
my local hardware store |
| 6-strand phone wire | my local hardware store |
| H-bridge motor controller IC for soil moisture circuit | SparkFun |
