Sunday we saw robots playing pool and an augmented reality pool game. Today we’ll complete the pool trifecta: virtual pool using a real cue stick and ball in another vintage video from Hack a Day’s secret underground vault. The video is noteworthy for a couple of reasons:
First is the year it was made: 1990. There’s been much buzz lately over real-world gaming interfaces like the Nintendo Wii motion controller or Microsoft’s Project Natal. Here we’re seeing a much simpler but very effective physical interface nearly twenty years prior.
Second: the middle section of the video reveals the trick behind it all, and it turns out to be surprisingly simple. No complex sensors or computer vision algorithms; the ball’s speed and direction are calculated by an 8-bit processor and a clever arrangement of four infrared emitter/detector pairs.
The visuals may be dated, but the interface itself is ingenious and impressive even today, and the approach is easily within reach of the casual garage tinkerer. What could you make of this? Is it just a matter of time before we see a reader’s Mini-Golf Hero III game here?
[Tom Gerhardt] has made this very interesting mud interface for a computer. Follow the link to see a video of it in action. It appears as though he’s using a laser grid of some kind to establish elevation. We might be way off on that though, there aren’t any details on the construction. He does mention that it is an open source hardware and software project, so maybe the details are available on request. In the video you can see it running as a projection surface where people are interacting with items directly on the mud. You can also see it being used as an external input device. People play Tetris using it in that example.
UPDATE: [Moon] reports from the ITP show that the tub has a 16×12 grid of generic pressurs sensors on the bottom. These feed into a MacBook Pro which is projecting on the surface. Despite the sparse grid, [Tom] says he gets good resolution by interpolating between sensors; it can detect a resting hand pivoting on the surface.
Microchip’s MCP6S21/2/6/8 are programmable gain amplifiers that multiply an input voltage by a factor of 1, 2, 4, 5, 8, 10, 16, and 32. The MCP6S22/6/8 also have selectable input channels for working with different signal sources. The multiplication factor and input channel are configured through an SPI interface. This chip is useful for multiplying a small input signal, and selecting among several analog input sources. We demonstrate the six channel MCP6S26 below.
We use the Bus Pirate to interface a new chip without writing code or designing a PCB. Based on your feedback, and our experience using the original Bus Pirate to demonstrate various parts, we updated the design with new features and cheaper components.
There’s also a firmware update for both Bus Pirate hardware versions, with bug fixes, and a PC AT keyboard decoder. Check out the new Hack a Day Bus Pirate page, and browse the Bus Pirate source code in our Google code SVN repository.
We cover the design updates and interface a digital to analog converter below.
A few weeks ago we wrote about our Bus Pirate universal serial interface tool. We used the recent holiday to add some new features, like a JTAG programmer, macros, frequency measurement, and more. A major code reorganization makes everything easier to read and update.
Check out the a demonstration of the new features below. We’re compiling a roadmap and wish list, so share your ideas in the comments. You can also see how we used the Bus Pirate to read a smart card and test-drive an I2C crystal oscillator.
[floe] wrote in to tell us about his multitouch based thesis work. While many projects have focused on the hardware side of multitouch, TISCH is designed to promote the software side. TISCH is a multiplatform library that features hardware abstraction and gesture recognition. This takes a lot of weight off of widget developers since they can specify known library gestures instead of writing the exact motions from scratch. Using TISCH also means a standard set of gestures across multiple widgets, so the learning curve will be much easier when a user tries out a new app. If you’re researching multitouch, check out this project and help improve the codebase.
Our fascination with multitouch is fairly well known, but it expands even further to cover all sorts of man machine interaction. Embedded above is a tech demo of g-speak, a spatial operating environment. The user combines gestures and spatial location to interact with on screen objects. If it seems familiar, it’s because one of the company’s founders advised on Minority Report. We doubt all this hand waving is going to catch on very quickly though. Our bet is on someone developing a multitouch Cintiq style device for people to use as a secondary monitor. It would bridge the gap between between our standard 2D interactions and gestures without making a full leap to 3D metaphors.
Brain activity is measured using passive or active electrodes. Passive electrodes require a conductive paste to make proper contact with the skin (examples: 1, 2). Active EEG sensors don’t need conductive goop because they have an amplifier directly on the electrode (examples: 1, 2, 3).
[Curiouslee] put up some pictures of his Siftables burn in. He got them in the mail with all their accessories and decided to make a special box to carry it all. He started with an ArtBin parts box and cut out dividers where necessary to make everything fit nice and tidy.
The Siftables are quite interesting. They are an information interface that is supposed to be more physical and natural. The analogy they use is a container of nuts and bolts can be sifted through quite easily using your hands. They envision us being able to sift through data similarly. They also mention that it could be used as a gestural interface as well.
Machinecollective.org is bringing rapid prototyping to every day artists and hackers. We’ve covered similar interfaces like the monome, MIDIbox, and Stribe. Machinecollective allows you to make your own input system using multiple blocks to get exactly what you want. The setup allows you to fit pretty much anything in a block that you can think of. They’re developing potentiometers, slide potentiometers, button grids, toggle switches, LCD’s, FSR/LDR’s, velocity sensitive pads, and touch screens.
Currently, they support software enviroments like: Processing, Max/MSP, VVVV, and Adobe Flash. That list will undoubtedly grow as the community plays with it. They envision the hardware connecting via MIDI, OSC, RS232, TCP/UDP, DMX, or USB.
They encourage others to design their own inputs. Community members can share modifications and designs, though there isn’t a forum or store yet. If you design a setup that you really like, they can even fabricate a single unit for you. Keep your eyes on this one, it could be a real hit.
A similar idea for general gadgetry can be seen over at Bug Labs. Starting with a base unit, you can add different input and output modules to create various useful functions. They currently offer GPS, a camera, a display, and motion sensing. Mix and match to make your dream gadget.
