Here’s one way to really keep the component count low. [David] developed an NES controller that doesn’t use any buttons. The copper clad has been milled to provide a pad which registers a button push based on capacitance. The board has a SIL header at the top, making it easy to plug into the Arduino board that reads the inputs.
[David] had trouble getting the Arduino pin read functions to respond fast enough for he NES console’s expectations. He ended up using commands to access the ATmega’s peripherals directly in order to achieve the target timing. Speaking of, he did his own sniffing of the communication scheme using a logic analyzer. The results of that work, as well as the board files and code are available at the site linked above. And there’s a demo of the controller used to play Super Mario Bros. in the clip after the break.
Texas Instruments just released a product they call the Capacitive Touch Boosterpack which is basically a touch-sensitive shield for the Launchpad. The video after the break shows an unboxing and demonstration of the product which TI is launching with a $4.30 limited-time price tag. The red PCB itself has a capacitive touch button in the center, surrounded by a touch-scroll wheel, which is centered in a proximity senor that takes up the rest of the board. There are also nine LEDs which look like they’re soldered on the underside of the board, through routed holes that mount them flush with the top surface. The pack also comes with a new MSP430 microcontroller, the G2452, which has 8 KB of flash memory and takes care of calibrating, reading, and processing signals from the board thanks to the software package that goes along with the add-on kit.
Looks quite nice. There’s a heck of a lot of information in the documentation for this hardware. We do wish it was a bit easier to find board layout information, but we’re sure it’s there somewhere.
Wanting to save space and weight on his project build [Florin] set out to find a way to add Ethernet connectivity without the magnetics. His ill-advised first try involved directly coupling two switches, frying both in the process. After some research he found that Ethernet hardware manufacturers have considered the need for devices without the magnetics and there are several application notes available on the subject. [Florin] followed the information that Realtek has for their devices and learned that they can be couple capacitively. After depopulating the magnetics from a second pair of switches he wired up some resistor-capacitor networks on a breadboard and got the connecting to work.
The chill of autumn is upon us, and with it comes the awkward sport of trying to work touch-sensitive phones and gadgets with gloved fingers. One can try toughing it out with fingerless gloves, or we’ve seen some costly solutions in the forms of specialized gloves and capacitive-compatible styluses, but sometimes simple is best: all it takes is a few stitches of conductive thread in the fingertips.
Conductive thread is available from various sources; SparkFun Electronics comes naturally to mind, but most vendors carrying the LilyPad Arduino will stock a suitable thread as well. Don’t fret if you’ve never sewn before — just a few simple loops are required, and it doesn’t need to be especially tidy. In principle this should work for trackpads and capacitive mice as well, if you use those in the field. For multitouch devices, add a separate conductive bit to each fingertip.
That title’s a mouthful but you’re already familiar with the technology and application of foot pads as sensors in games like Dance Dance Revolution. The usbddr project sought to make a USB connected DDR controller from scratch. The microcontroller used is an Atmel ATmega8 running the V-USB firmware for connectivity and uses the analog to digital converts to read in data from the capacitive sensors.
The physical implementation is cleaver. The base plate has a capacitor plate attached to the top of it and the tile has the other capacitor plate attached to the bottom of it. The two are separated by some weather-stripping which is spongy enough to allow compression, bringing the two capacitor plates together.
We’re not convinced of the long-term durability of the system. We certainly don’t think it will hold up to very much hard-core DDR playing. But we would love to see a Super Mario RPG style puzzle to unlock the door to the ‘castle’ at a child’s birthday party.
Microsoft is showing off five concepts for added mouse functionality. All of them seek to replace traditional move-and-click with touch sensitivity through either capacitive sensing, video recognition, sensor articulation, or laser scanning. We’re excited about the prospects of some of these features but at the same time wonder what this does to the price of this much-abused peripheral. After the break we’ll touch on each of the devices, along with time references for the video embedded above. Read the rest of this entry »
[Fritz] built this 600 joule capacitive discharge spot welder in a case scavenged from a Lincoln plasma cutter. All of the circuitry was designed by [Fritz] and the schematics are available on his website. He has a few other welding related project also documented on his site that are worth checking out. While this isn’t the first homemade spot welder we have seen, it is definitely the first one with a case mod. If you are not up to the challenge of building one quite as complex as [Fritz]‘s example, a microwave can be used as the donor appliance in simpler designs.
[Agent420] brought up this touchpad and VFD hack in the comments on our capicitive sensor guide post. He had broken dell laptop from which he harvested the touchpad and an HP laserjet that contributed the VFD. Though the touchpad communicates using standard PS2 protocol, he wanted to use it with his Atmel 8535 AVR which required him to write some custom code. In the picture above, you can see the VFD displaying the coordinates of his finger. You can download his code as well as the spec sheets for the different pieces on the project thread.
