Consider all the tools that modify how light is transmitted and received: lasers direct light in a tightly focused beam and telescopes let us focus on an area far away. While there are certainly ways to modify sound, these techniques are not nearly as developed as their light counterparts.
With hopes of changing that, researchers from the University of Sussex and the University of Bristol have been working with metamaterials—normal materials like plastic, paper, wood or rubber with an internal structure designed to manipulate sound waves—to build acoustic lenses.
The team demonstrated the first dynamic metamaterial device with the zoom objective of a varifocal for sound, as well as create a collimator capable of transmitting sound as a directional beam from a standard speaker.
The lenses are attached to the collimator, and can be used to direct sound from a speaker or two can be employed together to construct an adjustable focus system. Focal length is regulated by the distance between the two lenses, which is controlled by an Arduino Nano and a single stepper motor mounted to an adjustable rail.
Consider how interactive devices have come to dominate our lives. Once the purview of a select few in large laboratories, powerful gadgets—supercomputers even—are carried with us everywhere we go in the form of smartphones. And as everything around us becomes increasingly more connected, those that have no interest in the technical aspects of computing will still need to know how to configure the networked things throughout their homes.
As an experiment in interactive design, Austrian researchers Florian Güldenpfennig, Daniel Dudo, and Peter Purgathofer have come up with a ‘Magic Paradigm’ for programming.
Their project uses a wand with a built-in RFID reader, allowing it to sense which RFID tagged object it’s pointing to and register various sequences. This enables devices to be customized as needed, many of which contain an Arduino Nano as ‘active’ units and an nRF24L01+ module for communication. A central desktop/Arduino setup is also implemented to coordinate system elements.
We are surrounded by an increasing number of smart and networked devices. Today much of this technology is enjoyed by gadget enthusiasts and early adaptors, but in the foreseeable future many people will become dependent on smart devices and Internet of Things (IoT) applications, desired or not. To support people with various levels of computer skills in mastering smart appliances as found, e.g., in smart homes, we propose the ‘magic paradigm’ for programming networked devices. Our work can be regarded as a playful ‘experiment’ towards democratizing IoT technology. It explores how we can program interactive behavior by simple pointing gestures using a tangible ‘magic wand’. While the ‘magic paradigm’ removes barriers in programming by waiving conventional coding, it simultaneously raises questions about complexity: what kind of tasks can be addressed by this kind of ‘tangible programming’, and can people handle it as tasks become complex? We report the design rationale of a prototypical instantiation of the ‘magic paradigm’ including preliminary findings of a first user trial.
Hacky Racers, an electric vehicle racing series that’s part of the Power Racing Series, encourages drivers to put together their own hacky vehicle. While it looks like a lot of fun, in order to keep things relatively safe, current powering the car is regulated by an inline fuse from the battery, effectively limiting the top power output to the motor—thus keeping speed in check.
This means that while drivers need some control over how fast their motor is running, traditional PWM control where as much power is thrown to the motor as needed to keep it at a certain speed doesn’t really work. Instead, you need a system that controls how much current is provided. It’s a subtle problem, solved here with the addition of an Arduino Nano, which regulates output based on feedback from a current clamp sensor. While it won’t let a racer exceed the current limit, it does allow for maximum output when needed without tripping the fuse!
If you have a broken washing machine, you may want to think twice before disposing of it. As Stephen John Saville shows in this multi-use rotary table project, they can provide a wealth of parts, from the actual physical structure/table of the build, to a motor that’s able to run via AC or DC, and various other mechanical components. There’s even an electronic timer salvaged from an old microwave.
To keep the turntable running at the desired speed, he used an Arduino Nano connected to a triad circuit, along with an LM393 chip and optocoupler to implement closed-loop control. User feedback is shown on a 16×2 LCD screen, updated every two seconds to avoid interfering with speed control functions.
As spotted here, Sam Izdat decided to make a preamplifier for a friend who provides voice talent for audiobooks and the like. The primary audio circuitry for the build is provided by a purchased PCB based on the INA217 chip from TI, but from there things get a bit more interesting.
To complete the project, Izdat added a tiny Arduino-powered OLED display. This shows a VU meter, along with a variety of other animations, seen through a window in the enclosure made from a broken wristwatch.
The device was prototyped using an Arduino Uno, while a Nano was embedded in the final product, allowing everything to fit into the unique compartmentalized enclosure that he constructed.
The amplifier is based on the Texas Instruments INA217 chip, with an Arduino Nano and 128×64 OLED display providing the visualization. [Sam] was able to find a bare PCB for a typical INA217 implementation on eBay for a few bucks (see what we mean?), which helped get him started and allowed him to spend more time on the software side of things. His visualization code offers a number of interesting display modes, uses Fast Hartley Transforms, and very nearly maxes out the Arduino.
Teeuw’s clock features a trio of indicators, properly scaled and labeled for hours, minutes, and seconds, with control via an Arduino Nano, along with an RTC module for accurate timekeeping. Each indicator is housed in its own 3D-printed module, with white LEDs added for visibility.