Electric trimmers allow you to shed unwanted hair, with the side effect of a constant buzzing sound. This noise is related to the motor’s speed, which as shown in Device Orchestra’s video below, doesn’t necessarily have to be continuous. It could instead be tuned to play music.
After removing the stock circuit board on a trimmer and attaching new leads, the concept was first proved out on a benchtop power supply, varying the motor speed and notes via the voltage level. This behavior was then duplicated by an Arduino Due and motor driver module, using PWM output to produce a rousing rendition of “When the Saints Go Marching In.”
Slide whistles and recorders can be great for learning music, and perhaps a bit of fun, but what about teaching a robot to play such a wind instrument? The Mixed Signal’s MIDI-controlled system could be used for just that.
The project is comprised of a 3D-printed fipple and piston that go into a PVC tube, while air input is via a centrifugal blower fan. A plunger with a rack-and-pinion gear are used to move the piston back and forth, changing the note being played.
A keyboard provides the user interface here, though any number of digital audio workstation devices should be able to duplicate this human task if needed. It’s hooked up to an Arduino Due with a CNC shield, which controls the single stepper motor.
You can find more details on the fipple flute on Hackster and Hackaday, and see a demo of it in action below.
VersaTouch — which works on everyday surfaces — uses one or more receivers to measure sound waves emanating from the wearer’s “augmented” fingers, allowing it to calculate their positions and/or movements. The plug-and-play system can also sense force based on a changing audio signature and track individual digits by alternating each one’s sonic outputs.
Importantly, VersaTouch can be configured without permanent modification to the newly interactive surface. The setup includes an Arduino Due to receive signals, a Teensy 3.6 to control the transducers, and a MacBook to process the data and calculate the touch positions with a Java program.
VersaTouch is a portable, plug-and-play system that uses active acoustic sensing to track fine-grained touch locations as well as touch force of multiple fingers on everyday surfaces without having to permanently instrument them or do an extensive calibration. Our system is versatile in multiple aspects. First, with simple calibration, VersaTouch can be arranged in arbitrary layouts in order to fit into crowded surfaces while retaining its accuracy. Second, various modalities of touch input, such as distance and position, can be supported depending on the number of sensors used to suit the interaction scenario. Third, VersaTouch can sense multi-finger touch, touch force, as well as identify the touch source. Last, VersaTouch is capable of providing vibrotactile feedback to fingertips through the same actuators used for touch sensing.