Tag Archives: uno

Rapidly create your own capacitive multi-touch sensors with this kit

via Arduino Blog

You likely use touchscreens every day when interacting with your phone — perhaps even to read this article — but prototyping your own capacitive matrix is unfortunately out of reach for most makers and electronics novices. As seen here, researchers have devised a new technique that will allow for easier prototyping of this type of interface, which can function on both flat and curved surfaces, over a variety of materials.

To accomplish this, the team developed an Arduino library, as well as one for Processing, and used OpenCV to track multiple finger positions. Interactions have been tested with an Uno, Mega and LilyPad, and would presumably work with almost any other Arduino board as needed!

We introduce Multi-Touch Kit, a low-cost do­ it-yourself technique to enable interaction designers, makers, and electronics novices alike to rapidly create and experiment with high-resolution multi-touch sensors of custom sizes, ge­ometries, and materials. 

In contrast to existing solutions, the Multi-Touch Kit is the first technique that works with a commodity microcontroller (our implementation uses a standard Arduino) and does not require any specialized hardware. As a technical enabler, we contribute a modified multi-touch sensing scheme that lever­ ages the human body as a transmission channel of MHz range signals through a capacitive near-field coupling mechanism. This leads to a clean signal that can be readily processed with the Arduino’s built-in analog-to-digital converter, resulting in a sensing accuracy comparable to industrial multi-touch con­ trollers. Only a standard multiplexer and resistors are required alongside the Arduino to drive and read out a touch sensor matrix. 

The technique is versatile and compatible with many types of multi-touch sensor matrices, including flexible sensor films on paper or PET, sensors on textiles, and sensors on 3D printed objects. Furthermore, the technique is compatible with sensors of various scale, curvature, and electrode materials (silver, copper, conductive yarn) fabricated using conductive printing, hand-drawing with a conductive pen, cutting, or stitching. 

An IMU ring for low-latency mixed reality input

via Arduino Blog

Because of their ability to visually sense the environment, head-mounted mixed reality (MR) systems can detect when a user touches a wall or other surface. These surfaces can then become interactive panels, with the small caveat that they traditionally treat a finger coming within 10mm of the surface as a touch. 

While this leads to sometimes inaccurate readings, researchers at Tsinghua University in Beijing have implemented an inertial measurement unit (IMU) ring apparatus for contact sensing to increase precision from around 85% to just under 99%. 

The experimental setup for this exercise used an Arduino Uno to read accelerometer data, along with a capacitive arrangement to confirm when a touch actually took place. Accelerometer data was compared with readings from a Leap Motion optical sensor, which in addition to greater accuracy, also reduced latency.

Rolling robot transformed into a zip lining contraption

via Arduino Blog

MOREbot is an Arduino-powered educational robotic platform that’s currently available for pre-order. While the base kit is geared (literally and figuratively) towards building a small two-motor robot, MORE Technologies CEO Canon Reeves shows off how it can be reconfigured into an RC zip lining device in the video below.

The project uses the kit’s DC motors for traversing the cable, with O-rings that normally form the tires taken off in order to grip the top of a paracord. Everything is controlled by an Arduino Uno and a motor shield, while a Bluetooth module provides wireless connectivity. Control is via an iPad app, which simply rotates both motors at the same time as needed.

Since the parts are all modular, Reeves is planning on adding a few other attachments including a GoPro camera mount and perhaps even a servo that lets him drop a payload like a water balloon from it.

TipText enables one-handed text entry using a fingertip keyboard

via Arduino Blog

Today when you get a text, you can respond with message via an on-screen keyboard. Looking into the future, however, how would you interact unobtrusively with a device that’s integrated into eyeglasses, contacts, or perhaps even something else?

TipText is one solution envisioned by researchers at Dartmouth College, which uses a MPR121 capacitive touch sensor wrapped around one’s index finger as a tiny 2×3 grid QWERTY keyboard.

The setup incorporates an Arduino to process inputs on the grid and propose a number of possible words on a wrist-mounted display that the user can select by swiping right with the thumb. A new word is automatically started when the next text entry tap is received, allowing for a typing speed of around 12-13 words per minute.

Proxino takes your virtual circuit into the real world

via Arduino Blog

While circuit simulation tools become more accessible all the time, at some point it’s necessary to actual build your device and test it. Proxino, developed by researchers at Dartmouth College, takes a different approach, and enables you to virtually create a circuit, then test parts of it as needed with electronic components via physical proxies. 

To accomplish this, Proxino hardware sits on an Arduino Uno as a shield, and generates the virtual circuit’s responses to inputs. This setup allows for the implementation of physical elements like buzzers, lights, and sensors to complement the simulated environment, which can even be shared by remote collaborators in different locations. 

Proxino certainly looks like it could be an excellent instructional tool, or perhaps more!

Some tips and tricks for controlling a servo with an Arduino

via Arduino Blog

Servos aren’t particularly hard to control with Arduinos, and in fact there’s a library available just for that purpose. Actually making the connection between the board and servo and managing one’s power usage will require a bit more finesse.

In the video below, Jeremy S. Cook explains how you can create an adapter that goes between your servo and an Uno, including a capacitor to help even out voltage spikes. While in most cases you would want to supply power your servos separately from the Arduino, this technique seems to work well in a quick round of tests. 

In addition, the clip shows how to attach a servo and then detach it to cut it off, using a function outside of the main loop and no additional hardware. This would be very helpful in applications where power is at a premium — or if you just don’t want the servo jittering back and forth!