DEC16
How much electric current does your vehicle use?
How much electric current does your vehicle use in its various running states? I bet you have no idea... If you think it is under 150 Amps you can test it with this excellent device.
It is based on Allegro's ACS758xCB (ALLEGRO0758) IC that uses Hall effect to measure current flowing through it's terminals and ATmega8 microcontroller for the brains. According to the Allegro's IC specification, the maximum current that can flow through it is 150 Amps. The ATmega8 reads analog voltage that the sensing IC produces and sends it over RS232 to PC which receives and plots data for later analyzing. Installation of this digital ampere meter is a matter of placing it between the output of the alternator and its connecting wire. The source code is pretty straightforward and it is available for download on the project page.
Source: Josh - ImSolidState.com
DEC11
ArduiNIX is now open source hardware
When trying to make a nixie or VFD tube clock/display one might find it a bit hard to interface high voltages required to light up the display and low controlling voltages from a microcontroller.
This device handles all that and makes it extremely easy to interface many tubes since it supports multiplexing. The only thing left is to write some Arduino code and - voila, you are back in 1950's. Even if you don't like Arduino you can still interface this shield to any other microcontroller you like. The interesting thing about this project is that now it is totally open source hardware. So, if you don't want to buy the KIT, you can etch your own PCB and make one yourself! I just need to ask: Who doesn't love nixies?
Source: ArduiNIX
DEC8
Single Button Code Entry System
Don't want to use keys to enter your home... don't want that boring keypad either? If so, than this device is made just for you!
With a secret keying combination, actually 4 secret "modulated" key-presses on a single button, a relay is activated and any end-device can be actuated such as motor or a solenoid. This is great for garage doors but it might be a bit tricky to enter that code with lots of nines in it on a cold winter day. In the video we can see the automatic key-press entering with a rotary phone's dial, so it would be cool to open doors with this rotary input device instead of common boring keypad.
Source: Alan Parekh
DEC7
Open source hardware SD logger: OpenLog
How do you make a GPS logger? Well, the simplest way would be to get a GPS receiver, a microcontroller to parse NMEA data and SD or MMC memory card to store it all on. In that case you would need to make your own "file system" on memory card and PC application to download the data and put it all together. The other way would be to write FAT16/32 routines in microcontroller to store data in classic TXT files. Yet another way would be to buy DOSonChip IC that handles FAT and not worry a thing about the file system whatsoever.
This project is very very similar to DOSonChip. One big difference is that it is open source (open hardware) and based on ATmega328P! You can talk to it via serial communication using special set of "AT" commands to write, read and delete files. Very very cool stuff.
Source: Roland Riegel
DEC3
The Decision Maker - fun microcontroller project
Now this looks like a fun project to build and to use. You can use it on daily basis which is not recommended, or just in those mind-splitting situations.
While the traditional Magic 8 Ball gives you more answers which you can interpret however you like, this machine is straightforward - the answer is either yes or no. It is based on PICaxe 08M microcontroller which has internal A/D converter, but with source-code included it can easily be translated to PICBasic. The sensors are touch-sensitive copper plates - two coins actually, and when touched the current passes through your fingers or the entire body if more than one person is looking for the "universal" answer. The PIC reads the A/D value and randomizes two LEDs giving out a random result after the sensor is released.
Source: Chris the Carpenter @ GadgetGangster
DEC1
PC mouse based on accelerometer
This one is for all of you game freaks out there. Tired of dragging your mouse on a flat surface? Try tilting it in mid-air for a change!
It is powered from and connected to RS232 port with a special "driver" application written in Visual Basic. The main thing inside this mouse is Freescale's MMA6270 dual axis (X/Y) accelerometer which is connected to PIC16F690 microcontroller. PIC reads accelerometer values via internal A/D converter and transforms this data to serial data which is fed to RS232 port through MAX232 level translator IC. Later in the video we can see that this mouse works pretty good, the only thing it lacks is USB connection and standardized USB mouse protocol.
Source: uC Hobby
NOV25
Wireless XBee temperature sensor
XBee is one cool chip. I never worked with them so I didn't know that you could configure it to periodically read and send an analog readout of some of it's analog input pins. This way if you need to make some analog measurements you don't need an additional microcontroller, just good old XBee.
This project is a remote temperature sensor with LM34 temperature sensor and XBee at one side (the transmitter) and an Arduino with XBee and LED display to receive, parse and display the temperature value. Cool stuff!
Source: Michael Krumpus
NOV23
Innovative tiny password reminder
Now this is how professionals do it! Small, compact, easy to use and most important - very intuitive implementation of a simple password storage device.
This device has an amazing data-entry method. It can receive data from any web browser literally by "looking at the screen" with its photo-transistor. Custom web page with some JavaScript was made for data-entry, so to store a new password you just need to go to that web page and store it by pointing a device to the monitor screen. Access to stored passwords is PIN-protected and all data is displayed on 2x16 LCD display.
Source: Alberto Ricci Bitti
