Planet Arduino

A self-balancing robot isn’t a new idea, but we liked the aesthetics of [Maker ATOM’s] build. The use of a breadboard and a printed bracket looks good, as you can see in the video, below.

Like most first-time projects, though, there were some lessons learned. The power supply needs a little work and the range of balance compliance didn’t meet expectations. But those problems are soluble and, as usual, you often learn more from working through issues like these.

The heart of the system is an MPU6050 which provides a gyroscope and accelerometer along with fusion capability onboard. The availability of libraries for the sensor and the PID controller makes the project pretty simple to finish.

In particular, a PID control loop looks at the desired state of the system and the current state. It then computes an output based on the difference in state at the current time and over time in different ways. In other words, part of the output forms because of the raw difference but other parts of the output form due to accumulated error over time or from sudden perturbations. Adjusting the gains so that these parts stay in balance can be a bit tricky.

However, in the end, the two batteries were not sufficient to power the device adequately. Temporarily, a bench supply did the trick, but the batteries still needed to be there to provide some counterweights for balance. Experimenting wth some PID loop gains might also improve operations.

There are plenty of similar projects to draw inspiration from. The design doesn’t have to be difficult.

Hanging out at one side of the Atmel booth at Maker Faire was [Pamungkas Sumasta] who was showing off his Arduino cellphone called Phoenard. We really like the form-factor but its hackability is where it really shines. [Sumasta] showed off the menu system which is quite snappy and makes it simple for you to add your own applications. Software isn’t the only thing you can customize, as there’s a connector at the bottom of the phone. He showed off a breadboard attachment which was hosting LEDs of various colors. Their intensity can be altered using a simple slider app on the touchscreen. But there’s more power if want it. Also on exhibit was a self-balancing robot body which has a connector at the top for the phone.

[Sumasta] won the Atmel Hero contest and we assume that’s how he made it all the way to San Francisco from The Netherlands for Maker Faire. You can learn a few more technical details about Phoenard on the Facebook page.