The Shocking Potential of Energy Harvesters

Smart sensors and connected devices have become ubiquitous in modern life, changing the way we interact with our environment. From smart homes and cities to advanced industrial systems, the widespread use of these devices has led to the seamless integration of technology into our daily lives. In our homes, these sensors regulate temperature, lighting, and security, providing us with greater convenience and efficiency. In urban areas, they help to develop intelligent infrastructure by optimizing traffic flow, waste management, and energy consumption. Additionally, in industries, these devices have streamlined operations, enabling predictive maintenance and improving overall productivity.

However, the convenience offered by these interconnected devices comes at a significant cost. A major challenge lies in our reliance on batteries to power them. The constant need for recharging and replacement not only incurs substantial financial expenses but also generates an alarming amount of electronic waste. According to recent estimates by the Environmental Protection Agency, the global volume of discarded batteries has surged to approximately 180,000 tons annually, posing a significant threat to the environment due to their toxic components.

To counteract this issue, researchers have turned their attention to the development of energy harvesting devices, which can harness wasted energy from everyday activities, such as the act of switching on a light or turning on a faucet. By converting this otherwise squandered energy into a usable power source, our dependence on traditional batteries can be substantially reduced, if not eliminated altogether.

However, the implementation of energy harvesting solutions remains a complex task, as each environment generally requires a customized approach. Moreover, designing these systems demands interdisciplinary expertise, comprising knowledge in engineering, physics, and materials science, posing a significant impediment to their development. These problems could soon be a thing of the past, according to a team of researchers at Texas A&M University and the University of California, Los Angeles. They have recently created a system called E3D that greatly simplifies the process of designing, and 3D printing, one’s own energy harvesting devices.

The E3D toolkit takes a clever approach in leveraging the inertial measurement unit (IMU) in an off-the-shelf smartwatch to collect motion data from a wearer. This IMU data is fed into a machine learning algorithm that was trained to recognize 36 different types of everyday objects and kinetic interactions. In this way, commonly repeated actions, like opening a drawer, can be identified as good targets for energy harvesting activities. Moreover, the IMU data provides range of motion and trajectory estimates associated with the actions, which in turn can be used to design a 3D model for a device, of the correct scale, to harvest energy. Once 3D printed, the structure will have the attachments required to capture the wasted energy and use it to turn a DC motor, which in turn generates electricity.

A web-based application, with a Python back-end, was created to guide the user through the process of generating the finalized device design. This tool enables the user to choose the type of motion that they would like to exploit, and confirm the type of object that the device will be attached to. Further, the user can specify their desired type of energy collection mechanism, then fine-tune certain parameters to maximize the amount of energy that can be captured.

The design of the toolkit is versatile, in that it can adapt to virtually any environment. It also takes the complex design work out of the equation, by both identifying the best available opportunities for energy harvesting, and providing the designs for the devices to make it happen. E3D also lowers the bar in terms of cost — little more than a basic 3D printer is needed to get an energy harvesting solution off the ground. While the designs may not be especially aesthetically pleasing, they are functional, and could one day enable us to reduce our reliance on battery-based energy sources for a wide range of use cases.