Science + Technology + Engineering + Art + Math = STEAM
Everyone loves funky goggles and the Adafruit Neopixel rings are perfect for building a flashy pair. To kick it up a notch, we STEAMed up these goggles with some high tech sensors and a bit of applied math and physics.
The goggles are controlled by a Flora microcontroller with a LSM303 accelerometer/magnetometer to track the motion of the wearer’s head. A simple physics engine implements virtual pendulum display on the LED rings that swings in response to the motion of the wearer. The effect is much like a pair of hyperactive electronic googly eyes.
Everywhere we go with these, people ask us where they can get a pair!
Have you ever wanted to build devices that react to audio, but have been unsure about or even intimidated by analyzing signals? Don’t worry! This guide is an overview of applying the Fourier transform, a fundamental tool for signal processing, to analyze signals like audio. I’ll show you how I built an audio spectrum analyzer, detected a sequence of tones, and even attempted to detect a cat purr–all with a simple microcontroller, microphone, and some knowledge of the Fourier transform.
Continue on to learn some background information about the Fourier transform.
Mojang, the original developers of Minecraft have ported Minecraft to the Raspberry Pi. The result is called Minecraft Pi Edition. It is not the full Minecraft implementation, it is closer to the mobile version of Minecraft, but none the less a lot of fun.
This tutorial will show you how to install and run Minecraft Pi Edition on a Raspberry Pi.
Ultrasonic sensors are excellent at proximity detection. Whether on a robot or protecting an area. The Adafruit shop carries an excellent selection of sensors by Maxbotix.
The LCD display with an I2C backpack works well in Trinket projects as an informational display. It only requires two of the five Trinket pins.
Sensor monitoring is very common for Internet of Things (IoT) projects. This project can be placed in a very small enclosure and used anywhere sensing is needed. The code and concepts may be used in a number of your own projects.
Soft robots can potentially do a lot of jobs a hard robot made of steel and servos just can’t do. Something composed of soft, flexible structures and actuators might be able to burrow through the dirt like an earthworm, conform to complex objects like a human hand, and go huge distances on minimal power just like organic machines (bats, bugs, dolphins, etc) do.
One reason you don’t see too many robots like these is how difficult they are to design, plan, and manufacture. Either they’re made of lots of interconnecting soft structures knitted together with glue and fasteners (each seam meaning additional labor, expense, and chances of breaking), or composed of a single skin.
I’ve been poking at easier ways to manufacture soft robots and think that these single skin designs have a lot of potential. I think that making robots this way could lower their cost while increasing their strength and durability. I’ve been calling these single skin robots plionics.
The method consists of designing your robot in CAD and working backwards from there to produce an outer mold and an inner core. Casting silicone between the mold and the core forms the robot itself and melting out the core gives you the finished product.
You can find the documentation behind a whole series of these robots here.
In this tutorial I’m going to demonstrate how to put together one of my most successful robot designs (a strange squishy creature called the Trefoil Tentacle) using a combination of 3d printing, silicone casting, an arduino, and a bit of pneumatics.
The first thing a microcontroller project must do is communicate, often with us humans. While the Trinket mini microcontroller does not have a serial monitor built in (like the Arduino Uno), it can talk over various protocols including software serial, I2C (two wire), and SPI. Adafruit sells a wide array of I2C devices including a backpack to interface with a number of nice liquid crystal (LCD) displays – perfect as it only requires two of the five Trinket pins.
Monitoring sensors is very common for Internet of Things (IoT) projects. Here we’ll select the popular DHT series of temperature and humidity sensors.
This project can be placed in a very small enclosure and used anywhere environmental monitoring is needed. The code and concepts may be used in a number of your own projects.
Trinket and Gemma are perfect for small projects needing to receive some external event, triggering your own defined output. This project uses the Adafruit IR Sensor to first receive IR commands from a remote, then to use those codes in controlling a project of your own.
To learn about IR signals and how they are decoded by a microcontroller, see the IR Sensor Tutorial from which this tutorial is based.
Many larger Arduino projects use the excellent IRRemote library by Ken Shirriff. This library allows for multiple protocols and is quite flexible. But it relies on hardware specific to larger Arduino processors. This project simplifies the process of obtaining codes and using them to scale to the limits of the ATTiny85 processor in the Trinket and Gemma boards.
The Trinket’s USB port is used for uploading sketches, but you can also use it for some basic USB 1.1 devices. For example, under USB 1.1, you can make low speed USB devices such as…
many more… the drivers come from the operating system
MIDI devices (input notes from sensors, or generate outputs from notes, etc)
Custom devices (you have to write your own driver though)
There are a few more rare applications. However, USB 1.1 cannot do stuff like virtual serial ports or mass storage devices, these require USB 2.0, sorry. The easiest and most useful is an HID keyboard, which is a device that does not require a driver, and acts just like a plain keyboard, but a little more customized. I have created an Arduino library that will transform your Trinket into an USB keyboard, and give you an example of how to use the library to create a two button keyboard.
TRINKET 3.3V and TRINKET 5.5V versions. Trinket may be small, but do not be fooled by its size! It’s a tiny microcontroller board, built around the Atmel ATtiny85, a little chip with a lot of power. We wanted to design a microcontroller board that was small enough to fit into any project, and low cost enough to use without hesitation. Perfect for when you don’t want to give up your expensive dev-board and you aren’t willing to take apart the project you worked so hard to design. It’s our lowest-cost arduino-IDE programmable board!
The Attiny85 is a fun processor because despite being so small, it has 8K of flash, and 5 I/O pins, including analog inputs and PWM ‘analog’ outputs. We designed a USB bootloader so you can plug it into any computer and reprogram it over a USB port just like an Arduino. In fact we even made some simple modifications to the Arduino IDE so that it works like a mini-Arduino board. You can’t stack a big shield on it but for many small & simple projects the Trinket will be your go-to platform.
There are two versions of the Trinket. One is 3V and one is 5V. Both work the same, but have different operating logic voltages. Use the 3V one to interface with sensors and devices that need 3V logic, or when you want to power it off of a LiPo battery. The 3V version should only run at 8 MHz. Use the 5V one for sensors and components that can use or require 5V logic. The 5V version can run at 8 MHz or at 16MHz by setting the software-set clock frequency.
Here are some useful specifications!
ATtiny85 on-board, 8K of flash, 512 byte of SRAM, 512 bytes of EEPROM
Internal oscillator runs at 8MHz, but can be doubled in software for 16MHz
USB bootloader with a nice LED indicator looks just like a USBtinyISP so you can program it with AVRdude (with a simple config modification) and/or the Arduino IDE (with a few simple config modifications)
Mini-USB jack for power and/or USB uploading, you can put it in a box or tape it up and use any USB cable for when you want to reprogram.
We really worked hard on the bootloader process to make it rugged and foolproof, this board wont up and die on you in the middle of a project!
~5.25K bytes available for use (2.75K taken for the bootloader)
Available in both 3V and 5V flavors
On-board 3.3V or 5.0V power regulator with 150mA output capability and ultra-low dropout. Up to 16V input, reverse-polarity protection, thermal and current-limit protection.
Power with either USB or external output (such as a battery) – it’ll automatically switch over
On-board green power LED and red pin #1 LED
Reset button for entering the bootloader or restarting the program. No need to unplug/replug the board every time you want to reset or update!
5 GPIO – 2 shared with the USB interface. The 3 independent IO pins have 1 analog input and 2 PWM output as well. The 2 shared IO pins have 2 more analog inputs and one more PWM output.
Hardware I2C / SPI capability for breakout & sensor interfacing.
After finishing the LED Video Wall, I wanted to take advantage of the fact that each panel is modular and can be arranged in nearly any way imaginable. I present to you, the Adafruit Video Cube! Each side has 1024 LEDs, for a grand total of 6144 LEDs– it’s super bright in every direction!
Larson Scanner Shades (Trinket-Powered NeoPixel LED Strip Glasses) @ The Adafruit Learning System – We must repeat! Our “Kaleidoscope Eyes” goggles project was so popular that we wanted an easier option for newcomers to electronics. These “Larson Scanner” shades offer a lot of bling with fewer parts and less tricky connections. Freedom of choice is what you got!
The Adafruit Shield Compatibility Guide now literally goes to eleven: alongside the original five shields are details for six more: the Ultimate GPS Logger Shield, Wave Shield, LCD Shield w/16×2 Character Display, CC3000 WiFi Shield, 2.8″ TFT Touch Shield and 1.8″ TFT Shield w/Joystick. Pin usage, links to libraries and tutorials, it’s all there!
The Raspberry Pi has an on-board audio jack, which is super handy for all kinds of sound effects and speech, just plug and go! However, for when you want better audio for music playback, a USB audio card can greatly improve the sound quality and volume, this tutorial will show you how…
The CC3000 WiFi module from Texas Instruments is a small silver package which finally brings easy-to-use, affordable WiFi functionality to your Arduino projects.
It uses SPI for communication (not UART!) so you can push data as fast as you want or as slow as you want. It has a proper interrupt system with IRQ pin so you can have asynchronous connections. It supports 802.11b/g, open/WEP/WPA/WPA2 security, TKIP & AES. A built in TCP/IP stack with a “BSD socket” interface supports TCP and UDP in both client and server mode, with up to 4 concurrent socket connections.
Make a Raspberry Pi Wifi-Controlled Cat Laser Toy. This project will show you how to create a laser toy for your cat which is controlled over the web with a Raspberry Pi. The project demonstrates using a web application to control servos with the Raspberry Pi and an excellent way to keep your cat exercising when you’re umm busy playing minecraft. You can see an early version of the project on the September 7th adafruit Show and Tell show (~12 minutes into the show)!
Here’s a project to dazzle onlookers at Halloween parties, cosplay conventions, raves or at Burning Man. These full-color animated LED goggles attract a LOT of attention!
Adafruit NeoPixel LED rings fit perfectly inside the eyecups of most 50mm round goggles — a very common size. It’s almost as if these rings were made with this project in mind! (Actually, they were…then our clever customers came up with a million and one other uses.)
NeoPixel Ring – 16 x WS2812 5050 RGB LED with Integrated Drivers — Round and round and round they go! 16 ultra bright smart LED NeoPixels are arranged in a circle with 1.75″ (44.5mm) outer diameter. The rings are ‘chainable’ – connect the output pin of one to the input pin of another. Use only one microcontroller pin to control as many as you can chain together! Each LED is addressable as the driver chip is inside the LED.
Adafruit TRINKET – Mini Microcontroller. Trinket may be small, but do not be fooled by its size! It’s a tiny microcontroller board, built around the Atmel ATtiny85, a little chip with a lot of power. We wanted to design a microcontroller board that was small enough to fit into any project, and low cost enough to use without hesitation. Perfect for when you don’t want to give up your expensive dev-board and you aren’t willing to take apart the project you worked so hard to design. It’s our lowest-cost arduino-IDE programmable board!