Bringing drones to the people: Development of a low-cost fixed-wing UAV and multispectral camera for custom application in earth science field work, education, and outreach

Incorporation of Uncrewed Aerial Vehicles (UAVs) has greatly enriched earth science field data collection but the cost of acquiring UAVs, particularly those with customizable payloads, can be high, thus creating a barrier to using these valuable systems. We set out to design and build a low-cost 'student budget' drone and multispectral camera that could be customized for a variety of field, education, and outreach applications. UAV development followed an iterative design process guided by open-source plans resulting in a progressive series of 5 design iterations each incorporating lessons learned from previous versions. The final aircraft incorporates a flight controller for autonomous flight and a removable/customizable payload pod. Cheap components allow for easy and inexpensive repairs when damaged in the field. The final design cost is 625, but this is a max cost as a simpler system could be built based on the design for <300. The multispectral camera was built with the popular Raspberry Pi 2 computer, standard and infrared cameras, and low-cost/well-characterized filter material. The resulting multispectral camera collects imagery in the visible and near-infrared spectrum, with a total cost of ~$230. The UAV and camera cost ~1/5 & ~1/10 that of commercial systems, respectively. Unfortunately, the camera did not yield research-grade results due to image inconsistencies. Despite the lower cost, there are additional considerations when choosing a UAV and imaging platform including data needs, data quality and repeatability, ease of data collection and processing, required UAV pilot skill, and time investment for UAV construction. Given the ease of use and minimal pilot training time, commercial systems (e.g. DJI quadcopter) provide the best fit for many research applications like aerial photography or 3D outcrop modeling. However, for more complicated data needs (e.g., multispectral imaging) and/or projects with small budgets, a low-cost UAV with a customizable payload can open up new data collection avenues and scientific inquiry that was previously unavailable. Additionally, this approach has applications in STEM education to teach engineering processes, aeronautics, remote sensing, etc., and is useful as an outreach tool to educate general audiences about UAVs and their responsible use.