Towards Self-Sustainable Unmanned Aerial Vehicles
In recent years, the popularity of unmanned aerial vehicles (UAV's) has soared. The most common type of UAV's, the quadcopter, requires a large amount of energy to create lift and stay in the air. For this reason, it suffers from very large charging times and very short flight times. In this project, we explore another type of UAV, a blimp, whose helium-filled balloon makes it as light as air. Though blimps have limited the speed and are more susceptible to adverse wind conditions, it significantly reduced energy requirements. The largest part of any aerial vehicle’s power budget is the mechanical system. A blimp, however, requires significantly less power for horizontal propulsion. Furthermore, a blimp’s available surface area on the balloon. This can be exploited in conjunction with solar panels, which depending on area and lighting conditions, can provide a substantial amount of power. In certain cases, the harvested power can be used to directly power the blimp, either in a slow continuous movement, or in a burst-like fashion. Part of the main questions to be answered in this thesis is to determine the ratio between the input power harvested from the balloon and the power consumed for propulsion. There are of course different trade-offs between energy/velocity/time when traveling fixed distances that can be used as a way to reach the energy neutrality condition: Pin = Pout.
The main goals of this semester thesis is to build/test an energy-harvesting blimp and propose energy-aware algorithms to bring it as close as possible to self-sustainability. Using a commercially available platform , the student will make all the hardware/software modifications to have a fully controllable, remote operated blimp. The student will need to study the basic mechanics of blimps, and determine the best way to include a flexible, light weight solar panel covering the balloon, and characterize the power budget for standard indoor lighting conditions. Once a blimp prototype has been characterized, different power-aware algorithms can be proposed to either dynamically adjust propeller intensity based on the battery’s state of charge, or switch between continuous motion to burst-based movement. In particular the goals of the project can be summarized as follows:
- Develop a helium-based, remote controllable blimp prototype.
- Adapt freeRTOS  firmware to control the blimp.
- Add solar harvesting capabilities by attaching thin-film solar panels and charging circuits the to the blimp.
- Propose power-aware scheduling algorithms to achieve self-sustainability.
- Familiarity with embedded system programming in C.
- Basic knowledge of FreeRTOS  and STM32F4 MCU family  is favorable.
- 25% Theory
- 25% Study of existing systems
- 30% C embedded programming
- 20% Verification and experimental evaluation
Detailed Task Description
Meetings & Presentations
The student(s) and advisor(s) agree on weekly meetings to discuss all relevant decisions and decide on how to proceed. Of course, additional meetings can be organized to address urgent issues.
 Bitcraze Crazyflie2.0 http://www.bitcraze.io/crazyflie-2/
 Free RTOS http://www.freertos.org/
 STM32F405/7 http://www.st.com/resource/en/datasheet/stm32f405og.pdf