Inventing with the Raspberry Pi

At its core, a computer is any electronic device capable of receiving input, storing data, processing that data, and returning an output. This means computers can range in complexity from motion-sensing lights, to the device on which you’re reading this, to weather-predicting supercomputers; however, these tend to be largely fixed, premade computing devices. It would likely be prohibitively difficult to alter the basic functioning or connectivity of those devices.

The Raspberry Pi represents a return to the basics of computing. It comes with a CPU, GPU, memory, and power—but beyond that, everything is up to the user. Raspberry Pi’s don’t even come with a standard I/O interface; it’s left to the user to hook up mice, keyboards, sensors, screens, and speakers as they see fit. This isn’t intended as a limitation—rather as a way of freeing users to only include the elements they need—and to do so on the cheap.

This blog will detail a few particularly creative uses of the Raspberry Pi, so you can catch a glimpse of the possibilities this little device opens up!

A drum machine is a device that takes musicians’ physical, percussive inputs and translates them into sound. This is typically accomplished by providing a small grid of push-buttons for users to press. Raspberry Pi innovator Scott Garner took a different, tongue-in-cheek approach to drum machine interfaces.

Using the natural conductivity of beets, Garner turned the vegetables into capacitive touch sensors, allowing musicians to trigger notes simply by touching the plants. An MPR121 Capacitive Touch Sensor was used to collect the touch signals and send them to the Pi via an I2C bus, where the pygame library processed the inputs and triggered audio responses in real-time.

Garner has provided a detailed description of how he managed his solution, complete with a link to the relevant code on GitHub.

The Pi can also be put to more mellow uses. James Pavur has created a Raspberry Pi extension to brew his tea with robotic precision. There existed previously a number of bagged and loose-leaf tea-preparing devices, but these were typically feature-limited and quite expensive (often several hundred dollars).

Pavur’s solution can be built for less than $70 and has a number of useful features: It accepts voice commands; allows pre-scheduling of tea preparation; and can adjust steeping temperature, steeping time, and cooled temperature to the user’s exact preferences.

Perhaps most notably, Pavur began his project with no experience making mechanical devices. He taught himself everything from the coding to the soldering in an attempt to prove how simple these systems could be made, and he seems to have been successful in his efforts, encouraging others to take on similar projects.

Computers have now mastered chess so totally that, when asked whether he would ever publicly challenge the world’s top AI’s, reigning world champion Magnus Carlsen replied that he “wouldn’t stand a chance.” Libraries such as Houdini and Komodo return expert-level moves based on board states and time constraints, regularly crushing human players. One maker decided to put these libraries to use in the real-world by implementing the currently dominant Stockfish library on a physical chess board.

Soldering sensors on both the chessmen and the board, the maker provided real-time data to their Raspberry Pi about the state of the board, used Stockfish to evaluate the best response, and displayed the computer’s suggested responses to a small LED screen.

Their website contains a wealth of information about how this was accomplished, from the physical construction of the chessboard to the Python scripting used to communicate with the library.

Of course, the Pi isn’t limited to these particular applications; its versatility is one of its largest selling points. This page contains a huge repository of tutorials and projects, and a quick Google search will turn up similar collections for more specific purposes/setups (e.g., this list of nearly eight hundred projects for the Model B alone).

If you have an idea for a hardware/software application utilizing the Raspberry Pi, get in touch with TechArk today! We’d love to help you develop your very own custom solution.