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In the past decade, the personal ownership of unmanned aerial vehicles has exploded in the US and around the world. The rapidly declining size and cost of integrated circuits, sensors and embedded micro-controllers has lead to a flourishing community of hobbyists designing flight controllers with levels of sophistication approaching those for government and military applications. The typical flight assisted controllers integrate data from the user's control system and an Inertial Measurement Unit (IMU) in order to keep the craft level and on course. Deriving mostly from the radio controlled (RC) hobby industry, the flight control technologies for both rotary and fixed wing systems are generally community-built and open source. While this leads to rapid development and ease of modification, quality usually suffers. Because the community is not a community of professionals, best coding practices are often left behind, leading to unexpected failures. Such flight control systems are unsuitable for integration into US airspace due to their failure-prone nature and inability to mitigate the failure of flight control surfaces. Fixed wing systems can also be controlled without an onboard flight controller or autopilot, with a simple camera downlink and direct control surface control being sufficient for most firrst-person video (FPV) needs. This has left a hole in the market for such controllers, with all offerings lacking in professional features such as redundancy and failure mitigation. Our project suffered from many setbacks, including one team member becoming ill and another leaving the project halfway into development. We were also hampered by our choice to use the brand new STM32Cube Hardware Abstraction Layer (described in more detail in Chapter 9), as 3rd party support and example code was nonexistent or conflicting with official documentation. As such, we were required to greatly reduce the featureset of our system. To compensate for this, we implemented a basic software plugin system, where future developers can code their own flight modes and recompile the software without having to revisit the basic I/O required to setup and access the onboard sensors and actuators. Looking forward, we believe we have solved many of the issues involved with developing a flight controller on this powerful, next-gen platform. We have implemented basic IMU-based flight stabilization and control, and future developers can easily code in the more premium features, such as GPS and telemetry, on top of the existing foundation.

1. Introduction -- 2. From Community to Public Libraries: Liberalism, Education, and Self-Government -- 3. Cultivating Public Readers: Citizens, Classes, and Types -- 4. 'A mob of light readers': Holdings, Genre Proportions, and Modes of Reading -- 5. Knowing the 'Native Mind': Ethnological and Philological Collections -- 6. Conclusion

Context. Prescribed (or controlled) burning is frequently advocated as a means of reducing fuel loads in peri-urban forests to minimise the risk of high-intensity wildfires. An important consideration in prescribed burns is the impact on native wildlife.


Aims. An opportunity arose to follow the movements of radio-collared peri-urban swamp wallabies during a prescribed burn and after an unexpected wildfire in the same location a short time later. Movement data was used to assess the relative impacts of the prescribed burn and wildfire on mortality, emigration and habitat use; the behavioural responses and methods of avoidance used by swamp wallabies in response to an oncoming fire front; and the management implications for wildlife that inhabit fire-prone habitats in proximity to human settlement where wildfire mitigation is necessary.


Methods. Here we report on the movements of radio-collared swamp wallabies, Wallabia bicolor, before, during and after a prescribed fire and after a wildfire on the same site 6 months later.


Key results. No radio-collared swamp wallabies were killed during the prescribed burn and only one wallaby was observed to emigrate from the area post-fire. This contrasted to the wildfire where one wallaby died during or just after the fire and another perished in the post-fire environment a few months later. The wildfire also increased emigration post-fire.


Conclusions. We demonstrate that wallabies can avoid fire fronts and that this avoidance behaviour may be more successful during cooler fires. The prescribed burn provided a suitable habitat for wallabies but did not result in a shift in habitat preference.


Implications. Mitigation of the impact of prescribed burns on swamp wallabies may be achieved by allowing sufficient time for habitat complexity to re-establish between burns.