Design, Development, and Field Testing of the GlacierHawk: an Unmanned Aerial System for Geoscience Data Retrieval
Open Access
- Author:
- Volpe, Marc
- Graduate Program:
- Aerospace Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- December 12, 2019
- Committee Members:
- Jacob Willem Langelaan, Thesis Advisor/Co-Advisor
Sridhar Anandakrishnan, Committee Member
Amy Ruth Pritchett, Program Head/Chair
Sven G Bilen, Committee Member - Keywords:
- Unmanned Aerial System
glaciology
geoscience
aircraft design
aerospace engineering
rotorcraft
flight
Greenland
Helheim
glacier
geoPebble
sensor - Abstract:
- The GlacierHawk Unmanned Aerial System (UAS) serves as a data retrieval platform in support of the geoPebble sensor system developed at the Pennsylvania State University. The mission of the distributed sensor network is to wirelessly collect seismic and movement data across areas of interest on glacial surfaces over a multi-day deployment period. Due to the cragginess and volatility of the ice, the sensors are inaccessible except by air and may not be recoverable at the end of the defined deployment period. Should a sensor be lost to ice calving or system failure, some or all of its data may be lost, so the ability to retrieve data on demand during a deployment is of significant value. Furthermore, beyond serving as a backup, mid-deployment retrieval provides earlier access for analysis during longer deployments. The cost, risk, logistics, and required expertise of helicopter-based access to the geoPebbles makes such a method infeasible except for sensor installation and removal, so the concept of a drone-based solution quickly becomes attractive. This thesis outlines the design, development, and concept of operations of the GlacierHawk UAS, from initial concept generation to field testing over Helheim Glacier in southeast Greenland. The importance of endurance to the geoPebble mission, coupled with Helheim’s remote, austere operating environment, make battery selection and rugged, modular design two of the most critical factors in this application. To accommodate transport and field assembly, the GlacierHawk’s thin-walled composite airframe consists of a square-section fuselage tube and two cylindrical arm tubes, both of which are durable and easily removable. Battery storage and most cable routing are internal, whereas the Pixhawk autopilot, sensors, and Wi-Fi access point payload are externally mounted. The construction process leverages conventional production methods and materials with composites and additive manufacturing. Commercial-off-the-shelf components and systems are also leveraged with custom fabrication whenever suitable. During field testing with a deployed sensor array, the resulting 11.6-kg, 30+-minuteendurance quadcopter demonstrated the capability of flying glacier transit profiles and facilitating geoPebble data retrieval. Insights gained from the Greenland proof-of-concept mission are presented as concepts for implementation in future vehicle designs and field deployments. Identified areas for improvement include, among others, robustness of the positioning system and data links, redesigned landing gear, motor tilt for improved maneuverability, and increased endurance to support longer, more complex mission profiles.