Climate monitoring is a critical step towards understanding and mitigating natural disasters. Needing to monitor sizable spreads of land, ecologists turn to quadrotor robots. Simple and cost-effective to operate, quadrotor remote sensing bridges the gap between manned aerial surveillance and ground-based ecological monitoring methods.

Yet the need for manual sampling remains. This is especially true of densely forested areas; the canopy cover limits the useful data generated with above-canopy sensing. Just as the remote forest understories are treacherous for ecologists to navigate, robots face similar difficulties. Operating in confined spaces and far from the electrical grid, manoeuvrability and endurance become critical performance limiters. Production and maintenance also pose challenges in remote locations with limited logistical support.

For aerial robots to be productive in forests, they must become more compact and adaptable to their environment. This thesis addresses this aim and its challenges through the application of morphing designs on quadrotor robots. I explored the use of conventional morphing designs, using multi-part assemblies with rigid-body joints, such as bearings and ball joints. Utilising this design concept, I created multiple prototype tiltrotor-quadrotor robots. But as I strived to create lighter and more compact robots, conventional morphing designs became limited in their scalability and possible morphologies. Thus, I applied metamorphic designs with compliant mechanisms, creating robots that can fold their body to interact with and perch on trees.

The range of prototype robots demonstrates how morphing aerial robots can adapt to and take advantage of their environment to enhance their capabilities. Each robot showcases a different morphing quadrotor design. These robotic systems are analytically and numerically studied, experimentally characterised, and compared to identify the broader insights of morphing quadrotor design.

The unique shape-shifting abilities of the presented robots created performance trade-offs. But it is evident that a morphing quadrotor integrates capabilities without substantial increases in size or weight. Overall, integrated morphing design is an effective solution towards creating aerial robots for working within confined and changing natural environments.