The traditional theremin is more or less an audio oscillator with two metal rods. Using proximity sensing, one rod controls the pitch of the oscillator and the other controls the volume. [Teodor Costachiou] apparently asked himself the excellent question: Why does the proximity sensor have to use capacitance? The result is an Arduino-based theremin that uses IR sensors to determine hand position.
[Teodor] used a particular type of Arduino–the Flip and Click–because he wanted to use Click boards for the IR sensors and also to generate sound via an MP3 board based around a VS1053. The trick is that the VS1053 has a realtime MIDI mode, and that’s how this Theremin makes it tones.
Continue reading “The Infrared Theremin”
[Gregory McRoberts] was born with reduced vision in one eye and has never experienced the three dimensional sight which most of us take for granted. Recently he was inspired by the concept of a hearing aid to build a device which can augment his vision. Behold, the very Borg-like eye-patch that he wears to add distance and heat to his palette of senses.
The hardware he chose is an Arduino-compatible Lilypad board. It is wired to an ultrasonic rangefinder and an infrared sensor which monitor the area in front of him. The function of his right eye is still capable of seeing light and color, so a pair of LED boards are mounted on the inside. One is connected to the thermal sensor, displaying blue when below eighty degrees Fahrenheit and red when above. The other LED is green and flashes at a different speed based on the range sensor’s reading.
This is distracting when a person with normal sight wears it because of the intensity of the LEDs. We found [Gregory’s] explanation of this (called Helmet Fire) quite interesting.
When it comes to bathroom etiquette, [Nick] and the crew at Gadget Gangster are nothing less than proper gentlemen. Inspired by a Japanese toilet that automatically plays a “courtesy flush” noise in an effort to conserve water while masking sounds, they created the Toilet Buddy.
While the Toilet Buddy does nothing to cover up any aromas, it does provide some sound cover for those louder times. Not only that, it also helps serve as a reminder for other bathroom courtesies as well. When mounted on the tank lid, the Toilet Buddy alerts the last occupant to put the seat down and shut off the lights before leaving the bathroom. Built with a Parallax Propeller board, it uses IR and ambient light sensors to determine the position of the toilet seat and the status of the bathroom lights, playing an audio notifier when necessary. Now if it only sprayed air freshener automatically!
[Nick] points out that the Toilet Buddy is not limited to bathroom duty, and can be used in a variety of projects where light/motion sensing is required. Be sure to check out his writeup for some usage suggestions if you’re thinking of building one.
In the meantime, continue reading to see a video of the Toilet Buddy in action.
Continue reading “Toilet Buddy helps cover up bathroom noises”
There are so many good things about [Jose Julio’s] robotic spider. It’s design is dainty yet robust, and the behaviors encoded in the firmware are nothing short of spectacular.
The body is built from a piece of balsa wood in between sheets of carbon fiber. The legs are carbon rods, using two servo motors for left and right leg movement, and a third servo which can move the intermediary legs like the roll axis of a plane. An IR sensor rides on the front for obstacle avoidance, with system control courtesy of an Arduino. For more hardware info check out his build log.
Don’t miss the video after the break. You’ll see that the little bot can be manually controlled, or allowed to roam free. As we said before, the behavior is fantastic. Not only has [Jose] programmed interesting characteristics like the spider getting tired and sitting down for a while, but when it is awakened it leaps into the air. The movements are fun to watch for human and feline alike; if only your house cat could be so lucky.
Continue reading “ArduSpider entertains children and exercises pets”
What do you do with 100 player piano rolls but no player piano? You come up with a way to digitize the information for MIDI playback. The rolls have 90 columns worth of holes, 88 for the keys and two more for pedals. Voids in the paper cause a note or pedal to be played, so an optical sensor can be used to transform the analog data into digital information. Simple enough, you’ll just need 90 sensors. But this brings up quite an alignment issue. The solution is to use fiber optic cable to position the IR light source in a hand-made 0.2″ spaced jig. At least the spacing meshes nicely with standard 0.1″ protoboard, which is what was used for mounting the sensors.