3D printers may be old news to most of us, but that’s not stopping creative individuals from finding new ways to improve on the technology. Your average consumer budget 3D printer uses an extrusion technology, whereby plastic is melted and extruded onto a platform. The printer draws a single two-dimensional image of the print and then moves up layer by layer. It’s an effective and inexpensive method for turning a computer design into a physical object. Unfortunately, it’s also very slow.
That’s why Hasso Plattner Institute and Cornell University teamed up to develop WirePrint. WirePrint can slice your three-dimensional model into a wire frame version that is capable of being printed on an extrusion printer. You won’t end up with a strong final product, but WirePrint will help you get a feel for the overall size and shape of your print. The best part is it will do it in a fraction of the time it would take to print the actual object.
This is a similar idea to reducing the amount of fill that your print has, only WirePrint takes it a step further. The software tells your printer to extrude plastic in vertical lines, then pauses for just enough time for it to cool and harden in that vertical position. The result is much cleaner than if this same wire frame model were printed layer by layer. It also requires less overall movement of the print head and is therefore faster.
The best part about this project is that it’s a software hack. This means that it can likely be used on any 3D printers that use extrusion technology. Check out a video of the process below to see how it works. Continue reading “WirePrint is a Physical ‘Print Preview’ for 3D Printers”
One day while sitting in class in a Cornell University schoolroom, [Will] and [Michael] thought how cool it would be to send text messages to each other via their Texas Instruments calculators. Connecting the two serial ports with a serial cable was out of the question. So they decided to develop a wireless link that would work for both TI-83 and TI-84 calculators.
The system is powered by a pair of ATmega644’s and two Radiotronix RF Modules that creates a wireless link between the two serial ports. The serial ports are 3 wire ports, which can be used for several things, including acting as a TV out port. [Will] and [Michael] reverse engineered the port’s protocol and did an excellent job at explaining it in full detail. Because they are dealing with the lowest level of the physical protocol, there is no need for them to deal with higher levels like checksums, header packets, ext.
Be sure to stick around after the break to see a video of the project in action. It’s quite slow for today’s standards. If you have any ideas on how to speed it up, be sure to let everyone know in the comments.
Continue reading “Send Wireless TXT between Two TI Calculators”
[Chonggang Li] wrote in to share a link to the final project he and [Ran Hu] built for their embedded systems class. It’s called Piano Hero and uses an FPGA to implement a camera-based touch screen system.
All of the hardware used in the project is shown above. The monitor acts as the keyboard, using an image produced by the FPGA board to mark the locations of each virtual key. It uses a regular VGA monitor so they needed to find some way to monitor touch inputs. The solution uses a camera mounted above the screen at an obtuse angle. That is to say, the screen is tilted back just a bit which allows the images on it to be seen by the camera. The FPGA board processes the incoming image, registering a key press when your finger passes between the monitor and the camera. This technique limits the input to just a single row of keys.
This should be much simpler than using a CCD scanner sensor, but that one can track two-dimensions of touch input.
Continue reading “Camera-based touchscreen input via an FPGA”
This isn’t an FPGA emulating Mario Bros., it’s an FPGA playing the game by analyzing the video and sending controller commands. It’s a final project for an engineering course. The ECE5760 Advanced FPGA course over at Cornell University that always provides entertainment for us every time the final projects are due.
Developed by team members [Jeremy Blum], [Jason Wright], and [Sima Mitra], the video parsing is a hack. To get things working they converted the NES’s 240p video signal to VGA. This resulted in a rolling frame show in the demo video. It also messes with the aspect ratio and causes a few other headaches but the FPGA still manages to interpret the image correctly.
Look closely at the screen capture above and you’ll see some stuff that shouldn’t be there. The team developed a set of tests used to determine obstacles in Mario’s way. The red lines signify blocks he will have to jump over. This also works for pits that he needs to avoid, with a different set of tests to detect moving enemies. Once it knows what to do the FPGA emulates the controller signals necessary, pushing them to the vintage gaming console to see him safely to the end of the first level.
We think this is more hard-core than some other autonomous Mario playing hacks just because it patches into the original console hardware instead of using an emulator.
Continue reading “FPGA plays Mario like a champ”
Check out the game of chess going on above. It’s a virtual game where each player uses a glove as the controller. Or course the game board and pieces are missing from this image. They’re displayed on a computer monitor which both players can see.
The hardware rather simple, and we think it would be a great project to challenge your microcontroller skills. Each glove has an accelerometer attached to it, as well as a ring of copper foil on the pointer finger and thumb. One ATmega1284 monitors both gloves. The accelerometer data is used to move the mouse cursor on the screen, while the contacts are used to grip or release a playing piece. The game board and pieces are displayed using MATLAB with controller commands fed to it via a USB connection.
If you’re more into building a mechanized game check out this pair of telepresence chess boards.
Continue reading “Virtual chess uses glove controllers”
This video game gives your thumbs a rest while stretching those vocal chords. The pair of microphones seen above control the video game on the LCD display. Saying “Biu” will launch a projectile while “ahh” adjusts the flight path. The system was developed by [Tian Gao] as a final project for his ECE 4760 course at Cornell University.
The inputs are common computer microphones connected to some processing circuitry which he built on a piece of protoboard. This consists of some RC filtering and an LM358 opamp to get the signal ready for use with the ATmega1284. There is only one ADC on that chip so [Tian] alternates sampling from the microphones by using the multiplexer built into the chip. The video signal itself is an NTSC composite signal. To facilitate a reasonable frame rate he uses graphics that are packed in multiples of 8-bits. All in all this allows him to create a 160×200 pixel display.
All of this makes the game sound a little dry, but we dare you to listen to the video clip after the break without cracking a smile.
Continue reading “Voice controlled video game uses “Biu” and “ahh” for control”
Whenever we hear about ECE 4760 we take notice. That’s because a ton of fantastic hacked together projects have resulted from the class. It’s offered at Cornell University and focuses on designing projects based on microcontrollers. We look at it as a ‘how to connect everything to your microcontroller’ guide. The good news for you is that 34 lecture videos from the Spring 2012 ECE 4760 class are now available to watch for free online. When coupled with the course webpage itself (which outlines the reading, labs, and homework) this turns into an opportunity to work through the entire course on your own schedule.
If you need a brief preview, here’s a couple random things we’ve seen as final projects from the course: a digital saxophone, a handwriting decoder, and a haptic feedback unit for building your biceps.
We’re still working our way through the Nand2Tetris project, but we’re putting these lectures on our watch list for later.