The fact that you can build a cellphone around an Arduino is pretty neat. But we’re drawn to this project more as a testament to the advancement of hobby electronics. An [Average Joe] can build this thing with a minimum or background knowledge and without breaking the bank. Wow.
Of course this isn’t the first DIY cellphone we’ve come across. One of our favorites is this one which resides on a home etched PCB. There was even another Arduino offering with similar components back in September. But the one seen above really pulls it all together into a package that is usable for everyday life. The components include and Arduino Uno, GPRS shield from Seeed Studios, a TFT touch screen, Lithium battery and charging circuit, and a few other bobbles. All of it is mounted inside of a 3D printed case.
A simple phone calls for a simple UI and that’s included as well. The main menu has two buttons, one for placing a call, the other for sending a text. From there you get the virtual keypad seen above for typing out the phone number or composing a message.
The cost of an Ethernet shield for an Arduino isn’t horrible; generally between $17 and $32 depending on which one you buy. But have you seen the cost of a WiFi shield? Those are running North of $70! [Martin Melchior] has a solution that provides your choice of Ethernet or WiFi at a low-cost and it’ll work for most applications. He’s using a WiFi router as an Arduino Internet shield.
This is the TP-Link WR703N which has been very popular with hackers because of its combination of low price (easy to find at $25 or less) and many features: the USB is super hand and, well, it’s a WiFi router! The Arduino Pro Mini shown dead-bug style is talking to the router using its serial port. [Martin] wires a pin socket to the router, which makes the rest of assembly as easy as plugging the two together. The rest of his post deals with handling bi-directional communications with Arduino code.
If you really just need that direct Ethernet pipe consider building an ENC28J60 chip into your designs.
[Dirk] had a problem: while he already had an Arduino with an Ethernet shield, he needed WiFi for an upcoming project. Running a Cat5 cable was out of the question, and a true Arduino WiFi shield is outrageously expensive. He did, however, have a WiFi router lying around, and decided it would make a perfect WiFi shield with just a little bit of cutting.
The router [Dirk] used was a TL-WR702N, a common router found in the parts bins of makers the world over. Inspiringly, the size of the router’s PCB was just larger than the space between the Arduino’s pin headers. Turning the router into a shield is simply a matter of scoring the edge of the board and gluing on a few pins for mechanical strength.
Power and ground lines were soldered between the pin headers and the router, while data is passed to the Arduino and Ethernet shield through a short cable. It may not look pretty, but if it works in a pinch we can’t complain.
Scratch, a graphical programming language developed by MIT’s Media Lab, is an excellent tool for teaching programming. [Daniel] created an Arduino Sensor Shield to interface with Scratch, allowing for real-world input to the language.
This board is a derivative of the Picoboard, which is designed for use with Scratch. Fortunately, the communication protocol was well documented, and [Daniel] used the same protocol to talk to the graphical programming environment. The shield includes resistance sensing, a light sensor, a sound sensor, and a sliding potentiometer.
The main goal was to create a board that could easily be built by DIY etching. This meant a one sided board with as few jumpers as possible. The final design, which can be downloaded and etched at home, is single sided and uses only one jumper. Detailed steps on testing the board are provided, which is very helpful for anyone trying to build their own.
This board is perfect for educational purposes, and thanks to [Daniel]’s optimizations, it can be built and tested at at home.
Here’s an LED and Button shield for the Stellaris Launchpad (translated) which you can fabricate at home. It gives you access to a 5×5 matrix of LEDs, and adds four more buttons. In order to cut down on the number of I/O pins required to operate the lights [Cosimo] is using the concept of Charlieplexing. This lets him get away with just six driver pins and four button pins.
It’s not just the finished product that interests us here. The fabrication itself is worth clicking through to his project post. What initially caught our eye is the use of Kapton tape as an insulator so that clipped off LEDs could be used as jumpers flat against the top side of the board before populating the LEDs themselves. After those are soldered in place he masks them off, as well as the button footprints, and uses spray paint to protect the top side of the board. The final look is more polished than most at-home project boards.
This hexapod was made almost entirely via 3d printing (translated). The parts that you need to supply include a few fasteners to make connections, twelve servo motors, and a method of driving them. As you can see in the video after the break, all those parts come together into a little robot that functions quite well. The only thing that we think is missing are some grippy feet to help prevent slipping.
[Hugo] calls the project Bleuette. It is completely open source, with the cad files and source code available on his Github repository. There is additional information in the wiki page of that repo. This gives us a good look at the electronic design. He’s controlling the legs with an Arduino, but it’s all dependent on his own shield which features a PIC 18F452 to take care of the signals used to drive all of the servo motors. The board also has some peripherals to monitor the current draw and regulate the incoming power.
Continue reading “3d printed hexapod robot”
[100uf] built an LED matrix shield for the MSP430 launchpad. His goal with this design was to have it play Conway’s Game of Life. It does just that, as you can see in the clip after the break. But it’s just waiting to learn some more tricks. After he tires of watching the cellular automaton he can try his hand at making some LED pendant animations.
As you can tell, the board was made in his home workshop. It’s not etched, but milled using the CNC machine shown in this image gallery. This is a single-sided PCB, which works well enough for the surface mount components and the downward facing pin sockets. But we wonder how difficult it was to solder the legs of that 8×8 LED matrix. It does have plastic feet at each corner that serve as standoffs to separate the body from the copper layer. But it still looks like a tight space into which he needed to get his iron and some solder.
Continue reading “MSP430 Launchpad Game of Life shield”