Using 3D-printers and Low-cost Microcontroller Boards to Build Open-source Environmental Instrumentation

Recent advances in additive manufacturing (i.e., 3D printing) and low-cost, user-friendly electronics (e.g., Arduino) now make it possible to economically fabricate your own custom instrumentation. The ability to rapidly prototype sensor designs, literally on your desktop, has many advantages when developing new measurement techniques. The cycle of creativity is accelerated – think of Sebastian Thrun's law of innovation “Build it, break it, improve it.” Also, these fabrication methods can make the cost per unit very low, which has distinct advantages when a network of sensors is needed to characterize spatial variability. Finally, these technologies are often associated open-source hardware and software, a feature that promotes collaboration among research groups and across disciplines. The objective of this research was to determine the utility of using 3D printers and Arduino boards to build a variety of measurement systems, including: a complete weather station, data loggers, heat pulse sap flow gauges, and a robotic air sampling system. The goal was to develop instruments that most people could build with off-the-shelf components and only elementary skills in fabrication and electronics. Custom components were printed in ABS plastic using a hobby-grade 3D printer (e.g., RepRap Project). Performance of the prototype instruments was compared to research grade equipment or some other independent standard. The weather station included custom 3D printed components such as a photodiode pyranometer and aspirated air temperature shield. The bodies for the sap flow sensors were also 3D printed and the control electronics were built around the Arduino. The CNC design framework used by the 3D printer was ”hacked” and repurposed to make a novel air sampling system that routed air samples to glass serum bottles. These technologies could have many applications in meteorology and environmental science.