There are plenty of great products on the market that do not need any electronics to operate. Gyro Bowl, Eggies, and Hot Huez all function just fine without any batteries or LCD screens. However, there is no doubt that some products, like many toys, pieces of fitness equipment and music players need electronics to have marketable appeal. When the Edison Nation engineering team gets a project like this, we need a quick and reliable way to prototype the circuits. Most of the time we choose a microcontroller to do the job. In this installment, I will explain what microcontrollers are and how they are used to make great prototypes.
A microcontroller is a small integrated circuit chip that has a processor inside of it and some onboard memory. Code can be written to make the processor read inputs from sensors or buttons, make decisions based on the coded logic, and send outputs to displays or LEDs. Simple code can make the micro controller blink an LED when a button is pushed, but more complex code can be found in quad copters that take the input signals from the gyro sensors and change the speed of each of the motors to keep the copter hovering in the air. The creative possibilities with micro controllers are endless, they are easy to program, and there is all manner of example code on the web. This makes it very easy for the EN engineering team to use them in our electronics projects.
The most popular microcontrollers right now are the Basic Stamp from Parallax, and the Arduino Uno, and these are what we use the most in the Edison Nation shop. They are similar in their number of inputs and outputs and their processing speed, so the knowledge of the programming language are the primary factors when the engineering team chooses a microcontroller for a project. I had Basic Stamp experience from college when I taught a class on it, and I have used it for many of my electronics projects. The Arduino is open source and has gotten a lot traction in the maker and hacker communities. The programming and implementation of hardware like LCDs and sensors is really easy, so we have been using it more lately. Both have sensors and peripherals available at our local Radio Shack store which is a help when we need components on the quick. There are other players in the microcontroller space like the Raspberry Pi. It has a much faster processor and can take keyboard inputs and produce graphics like a normal desktop computer. It is also inexpensive, but we have yet to use it on any projects.
When we start doing electronics development work with micro controllers, we usually start by creating an outline of what we want to achieve before doing any circuit building. We figure out what inputs and outputs we need and starting sketching out what the circuit might look like. Then we find sensors that have the accuracy that we need and check to make sure they are compatible with the microcontroller board. If there is a sensor available that also has example code or an Arduino library we tend to use those. If we need a display or other outputs like an LED, a servo, or a relay, we source those too. Then we use a breadboard to build the circuit and write the code we need. During this step is where most of the iteration happens. Inevitably a sensor gets broken, code is wrong, or something gets shorted out, and it takes a few tries to get everything working in harmony. Once we have a working circuit and code we get a PCB (printed circuit board) made to clean up the circuit and get it small enough to fit in the product. Then we make small changes as necessary.
We have used microcontrollers in a bunch of interesting projects. In a previous installment of ProtoTYPING, I introduced the Huber board bender. This product used a Basic Stamp 2 microcontroller to read position sensors and display the amount each board would bend on and LED display when subjected to the same load. The EN engineering and design teams competed in the Red Bull Creation competition last summer. We used an Arduino board (re-badged as a Bull-duino for the competition) in our audition video when we turned a cubicle into a fully-stocked bar. We also used both a Basic Stamp and an Arduino when we made our environmental foosball table (dubbed “Fools-ball”) to control the motion of our goalies as well as control the rain and wind on the table. Watch a video of Fools-Ball.
We have also used microcontrollers on the slow-pull dog leash in season 4 of Everyday Edisons. Once the filming was done we used it to make a test bed to read the force on the leash in different configurations.
Microcontrollers are a great tool that the EN engineers use all the time. More and more projects and innovations rely on electronics and sensors to achieve the desired result. Microcontrollers like the Basic Stamp and Arduino allow us to quickly build circuits and code to make prototypes and “fail more quickly” so that we can get to a great product sooner. For those who want to explore microcontrollers for your development projects at home, there are starter kits available at Radio Shack or online through the Maker Shed website.