Here is something that will definitely catch the attention of your guests, although the project’s author wasn’t lucky enough with the WAF (Wife Acceptance Factor). A laser beam showing the time on one of your walls, an unusual clock indeed and very easy to build.
Tracking the time is done by an Atmel Attiny24 microcontroller. It feeds a PWM signal to a servo motor that rotates the laser. The laser, controlled by the Atmel and driven by a npn transistor, can be set as a continuous line or pulsating. A crystal oscillator is used for best accuracy. Connector J1 is used to set the time and for settings, using a jumper. It can be set to show hours or seconds for example. Of course you could replace this with push buttons and/or switches.
It’s best to adjust time at fixed hours otherwise you will have to count seconds to adjust minutes. Also depending on the type of servo motor you will be using you might need to play with the values of servo’s rotation span. There is a version available using the Arduino.
The code is written in C and it is very well commented and that comes in very handy if you want to add some modifications. There are some things you will have to look out for when recompiling. Circuit diagram and code are available in the project as well as pictures and a video of the sundial.
When i first saw this project i thought this could be turned into one of those dance steps learning game. The device consists of a 3×3 matrix of buttons. The system memorates the sequence in which you press the buttons and then plays it for you by lighting a LED under those buttons. You can also program multiple sequences. If you don’t press any button for a longer period of time, 4 seconds i believe, the device goes from recording to playback.
It is quite an interesting memory game, and can be transformed into a larger project. Like in one of those smart houses… in case you get lost this device will show you what path you took. On the other hand the algorithm behind this project can be used in beat generators, sequencers, power distribution sequencers and many others.
The Nove Bit as it was called is using Arduino and a TLC 5940 microcontroller. Source code is available for download as well as some instructions on how to build it.
Here is a good project for those who want to start with robotics. Fairly simple and if you are using a breadboard there is no soldering involved. It is a vehicle that follows a light source using two LDRs, two servo motors, two wheels and an Arduino as its brain. The two LDRs are placed one on the left and one on the right side of the vehicle and each one controls the motor from the opposite side.
Although this project can be done using discrete components alone, using an Arduino allows you to further develop the project. Light is detected by the two LDRs. Each LDR is connected in series with a resistor between Vcc and ground forming a voltage divider. The joint point between the LDR and the resistor is connected to one of the Arduino’s analog inputs.
You will need to play a little bit with the values of the resistor so that you get the right sensitivity for light detection. A variable resistor could be very handy. The motors who spin the wheels are two hacked servo motors. Since servo motors don’t spin 360 degrees there is a way explained in the project to transform them into gear motors.
Servo motors are however pretty easy to control with the microcontroller. You have a center value which will make the motor stand still and if you add or subtract from that value it will make it go forward or reverse. You will need to run a few tests to determine these values and to adjust the light sensors.
Arduino based projects are very popular, because of its versatility, ease of operation and pretty large amount of projects available to be put into practice. This being said it’s not unexpected to see clones being made like the Coreduino.
Named like this because it uses the core of the Arduino board, the ATmega168 microcontroller and its oscillator components 16Mhz Xtal and the two 15pF capacitors. Coreduino’s PCB is smaller and can be easily connected to a breadboard. There are soldering bridges that let you power the board from ISP or USB. The programmers were built on separate PCBs and this way you can use the same programmer for many Coreduino boards. USB and Serial programmers are presented.
The USB programmer uses a FT232RL chip to convert data from USB to serial and send it to the ATmega. It can also power your Coreduino board and you can select the logic level to either 3.3V or 5V. The serial programmer has two level shifters made with discrete components and you can have RTS or DTR line to reset the Coreduino but you can not power the board with it.
In the project you will find all schematics and PCB layouts, everything you need to get it done.
“Bilbo, look out for the Dragon!” cried Frodo. “Dragon? Nonsense! There hasn’t been a Dragon around here for a thousand years!” said Bilbo… but little did he know what some people are building in their dungeons. Presenting “Puff” the fire fighter Dragon. I bet Smokey the Bear will lose his job soon, as forest fire prevention mascot.
The Dragon, once it finds a fire, has it’s eyes fixed on it, closes in and puts the fire away with his breath. He he I know what your thinking but it’s napalm glands are only active in angry mode. If he fails to put down the fire after two sweeps, he backs away to save his skin.
This project is based on an Arduino processor and MotorShield. Two gear motors with 224:1 ratios and PolyMorph axle extensions are used for movement. Puff moves his head to left and right with the help of a servo and does that in a 60-120 degree range. His “eyes” are two light sensing resistors, each one placed at the end of a heat shrinking tube so that localization of the fire is more precise. Also you must isolate the back of the resistors as well, for the same reason.
Once his eyes are fixed on the fire his breath comes from a little fan and it’s motor. A Sharp IR sensor provides cliff and obstacle detection. You will have to angle it so that it’s focus point falls at 10cm away on the floor. The Dragon’s head is made of paper that you can print with your desired model.
