Garage sale Arduino and Robot Projects ... Zee Other Technology
Monday, May 6, 2013
EZ Bo show all his sensors
Wednesday, April 24, 2013
EZ Bo fetches an LED pack
Thursday, July 9, 2009
A Really Blinking LED
Does a buck sound about right?
So let’s be off to the Dollar Tree, where everything there is $1. There I found several interesting things that might make for future, simple and fun Arduino experiments, but for this project I settled on the Sports Air Horn. This is a really loud, non-electronic horn, complete with three very bright, flashing LEDs, one red, one green, and one blue.
OK, now let’s tear open the package and see what we have. That plastic thing is actually a horn. If you blow into the small hole on the side,this thing creates a very loud sound, but our goal is to examine that little circuit board inside. The top of the horn is covered with a plastic/rubber membrane, however the bottom of the plastic case is wide open.
Going in from the bottom, use a screwdriver to carefully break away the circuit board. You will hear plastic cracking as the circuit board separates from the housing, but don’t worry, I broke away four of these circuit boards without damging the circuit board or the housing. You can still use the horn itself (sans lights) to irritate the neighbors.
It’s that circuit on the right that we are after. It can easily snap out of its plastic cover.
Looking at the circuit board we see three batteries (covered with metal holders) connected together in series to provide 4.5 volts for powering the circuit. We don’t care about the connections between the batteries, we only need to locate a final positive and negative contact point, that will allow us to connect to the power supply from the Arduino. We will also need to find a place to attach a wire giving us a means to connect to an OUT pin on the Arduino.
On the printed circuit side; all the spots marked with an X are connections for the batteries – we can remove the batteries and ignore these. BTW if you leave the batteries on the board, they can power the Arduino for a while. The red “+” is where we will connect +5 volts and the black “–“ is the ground connection. The yellow “P” point is where we will solder a wire for connection to an Arduino OUT pin. The switch (which will remain soldered to the board in the event we desire to test the LEDs) connects P to ground or in Arduino terms, “to LOW”.
Solder the wires as shown below: The red positive 5 volts wire is shown soldered to the right of the little hole (the same hole the black negative wire enters the board), however it can just as easily be attached to any of the other point shown by the red + sign. If you remove the AG10 batteries and their holder, there will be no + connection to the solder point shown below, because the battery holder acts as a conductor for the 5 volts.
Here are two pictures of the finished Blinker, one attached to Arduino pin 12, using a Proto Shield and a mini solderless breadboard, and one directly connected to the Arduino.
The Arduino program, or sketch, is a simple modification of the original blinking LED exercise. The code is available in the code listings on the right hand sidebar as a text file. Simply copy and paste it into the Arduino code window.
The LEDs are very bright!
Have some fun playing with the delays in the code. The circuit has a life of its own, so the timing may not seem to behave perfectly. I am considering making an array of 9 or more of these (3 sets) using three OUT pins and a variety of delay timings.
At the Dollar Tree,I also picked up a $1 noise maker; I plan to combine with these Really Blinking LEDs in another project.
Tuesday, June 23, 2009
Arduino Experimenter Strips
On the underside of the Experimenter Strips I have attached felt pads. Rubber pads also work. The pads have been cut in half on the top and bottom, and the two sides to make for a snugger fit into the Sensors Lab console. They also make nice feet when using the strips independent of the Sensors Lab console. The round pads are the original shape.
That’s a bit of the blue poster putty in the lower right corner.
Here is an Experimenter Strip with the Arduino fastened with screws. The breadboard is in preparation for LED experiments. It contains a 2 digit, seven-segment LED (scrounged from a digital answering machine), a 10 bar LED array, and a bi-color LED. The little 1/8 watt resistors were removed from the same digital answering machine. The speaker was also scrounged from a digital answering machine. Notice the red and black 5 volt and ground wires coming from the Arduino and attached to the breadboard.
This Experimenter Strip uses an Arduino with an Adafruit Proto Shield attached. The little circuit board at the right end is taken from a garage sale toy, made to digitally records short sounds.
The shield has been modified with the addition of a 5 socket header, (found at the left side of the mini breadboard, with the yellow numbers) designed to access components soldered on the shield circuit board. I used three components already part of the shield (red and green LEDs and a switch), and added the piezo and photo cell (with a 10K resistor). The second lead on each of these components goes to ground.
1 red LED
2 piezo buzzer
3 photo cell
4 push switch
5 green LED
Monday, June 22, 2009
Electronic Sensors Lab with your Arduino
The Sensors Lab makes a handy platform for laying out Arduino projects and comes with a nice selection of sensors to experiment with. The built in speaker, buzzer, potentiometers (three), LEDs, and spring connectors reduce some of the wire mess that cannot be resolved using only those solderless breadboards. In addition there is a small solderless breadboard built into the Sensors Lab.
Radio Shack does not list them on line any more, but you may find one in a local store for around $50, a bit expensive. I have seen them go on eBay for as little as $16 in new condition. I bought mine from an individual through Amazon. If you find one of the lab consoles without the manual, Radio Shack offers a free pdf version on their website http://www.radioshack.com/graphics/uc/rsk/Support/ProductManuals/2800278_PM_EN.pdf
I removed the screws and lifted off the top. Be careful of the nine volt battery connector, it is worked around the bottom of the console so you can change the battery without opening the console and is in turn soldered to the power switch. I typically do not use the battery, but instead attach an AC adapter to my Arduino and feed the regulated 5 volts to the rest of the board. This is so I can quickly remove the top of the console and store wires and components in the bottom part as shown in the figure below. It is handy how it comes complete with all those dividers. I am still considering using the power switch at some point, but so far it has not seemed necessary.
I attached a terminal strip to the back of the top for those times when I needed to connect something with wires larger than the breadboards allow. This is the only permanent change made to the original console (two holes drilled). Otherwise the whole thing can be returned to its original condition if needed.
12-Position European-Style Terminal Strip Model: 274-680 $2.89
I attached a second solderless breadboard (http://www.adafruit.com/ $5), using removable poster putty ($3 for 2 oz.) over the speaker and buzzer holes. This really gives you more “circuit space”. The poster putty holds remarkably well and is available in office supply stores.
Arduino Experimenter Strip
Now for the really useful part. On the left hand side is a deep tray used for holding the sensors. I decided to cover it with a small perf board that holds
1. the Arduino
2. another solderless breadboard
3. useful small parts like speakers, piezo buzzer, and small circuit boards
Make more than one of these Experimenter strips; perhaps one for LEDs, one for motors, etc. I have tried several ways to attach both the Arduino and breadboard to the perf board, e.g. screws, removable putty, or just rest the Arduino’s rubber feet on the board. Buy one of the large (6” x 8”) RS perfboards, and you can make 2 or 3 from one board.
Radio Shack Pre-Punched IC-Spacing Perfboard 6” x 8” Model: 276-1396 $3.99
Here is the full blown Arduino Sensors Lab complete with a green colored LED light (the LED is white), clipped to the magnetic sensor plugged into the sensor socket.
Thursday, June 11, 2009
Garage sale Arduino Projects
What do I mean by garage sale philosophy? Basically anything that can be recycled, repurposed or reused. So this includes any old electronic device, or toy that will be dismantled and scavenged for parts. These repurposed parts can come from yard sales, garage sales, flea markets, auctions, stores like Goodwill and the Dollar store, Ebay, or dumpsters. We will take apart these used electronic contraptions, save the parts, and ultimately use them in Arduino experiments, and along the way, with some luck, have fun and learn something.