– Want to build your own durable, battery-free electronic device? Well, now you can!
September 29, 2021
New technology allows hobbyists to build, program smart and durable devices with infinite lifespan.
Image: TU Delft / Northwestern University
Last year, computer engineers from Northwestern University and Delft University of Technology (TU Delft) introduced the world’s first battery-less Game Boy, which recovers both solar power and power. User kinetics by mashing buttons to power unlimited life.
The same team are now presenting a new platform that allows manufacturers, hobbyists and novice programmers to create their own battery-free electronics that run on intermittent and recovered energy.
Called BFree, the system includes energy harvesting hardware (the BFree Shield) and a blackout-resistant version of Python, one of the most accessible and widely used programming languages. All the user needs is a basic understanding of Python in order to quickly and easily transform any do-it-yourself (DIY) smart device into a battery-less version. With this technology, novice programmers can now turn their DIY battery-powered motion sensor, for example, into a solar sensor with infinite lifespan.
The researchers presented their work today (September 22) at UbiComp 2021, the premier conference on ubiquitous computing. Users can find instructions on how to use the new technology here.
‘Ask the wrong question’
“Right now it’s next to impossible for hobbyists to develop devices with battery-less hardware, so we wanted to democratize our battery-less platform,” said Josiah Hester of Northwestern, who co-led the work.
All over the internet, manufacturers are asking how to extend the battery life of their devices. They are asking the wrong question. We want them to forget about the battery and instead think about more sustainable ways to generate power. “
“The manufacturer community is generally more interested in deploying their devices quickly, and that speed doesn’t always go well with durability,” said Przemyslaw Pawelczak of TU Delft, who co-led the work with Hester. “We wanted to design a viable product that could connect these two worlds. “
The Maker Movement’s battery problem
Technology-driven extension of DIY culture, Movement Maker comprises a diverse group of inventors, designers and computer programmers who build their own hardware and software for electronic devices, including motion sensors, displays, actuators and more.
Combined with cloud computing, the ability to develop fast, inexpensive, and connected devices enables the Internet of Things (IoT). These DIY enthusiasts make everything from home automation devices to weather stations and everything in between.
As the growing number of people able to build and program devices present an exciting future for technology, Hester, Pawelczak and their team are intimidated by the number of batteries that will be used up and eventually end up in landfills.
“A lot of people are predicting that we’re going to have a trillion devices in this IoT,” Hester said. “That means a trillion dead batteries or 100 million people replace a dead battery every few minutes. This presents a terrible ecological cost to the environment. What we’re doing instead is really empowering the people. We want everyone to be able to effortlessly program devices in a more sustainable way. “
‘Invisible’ for the user
But just giving up a battery isn’t as easy as it might sound. When devices bypass the battery and instead rely on energy harvesting, power is no longer constant. If the sun passes behind a cloud, for example, solar energy may be temporarily interrupted.
With BFree, researchers have solved this problem. The technology allows devices to run continuously with intermittent energy. When the power is interrupted, BFree stops the calculations. When power returns, it automatically picks up where it left off without losing memory or needing to go through a long list of operations before restarting. Not only does this save energy, but the technology is also more intuitive to the user than traditional programs, which lose all memory of what happened just before a power failure and have to restart from the very beginning.
To make the process user-friendly, the researchers coded BFree with software to interpret Python programs for battery-less devices. A user only needs to attach the BFree Shield to the manufacturer’s Adafruit Metro M0 platform (or modify it slightly to work with other CircuitPython-based platforms) and then program the device as he usually would. The BFree software takes care of the rest, allowing the program to run without batteries – only from the recovered energy – and to run perpetually in the event of a power failure.
“We wanted to make it completely invisible to the end user,” said Kortbeek, a doctoral student in Pawelczak’s group. “So we tried to keep the same original device experience without the user seeing how we modified the software to interpret Python files for battery-less technology.”
“Now anyone can build and program smart, sustainable devices,” Hester said. “This makes the future vision of ubiquitous computing more sustainable, useful and environmentally friendly. “