Date of Award
Master of Science in Electrical Engineering (MSEE)
Electrical, Computer, and Biomedical Engineering
As Unmanned Aerial Vehicles (UAVs) become more commonplace in society they encounter greater risks due to crowded environments. In this thesis a novel solution for the locomotion of a Fully Actuated UAV is proposed, by having a UAV use a ring to roll along a surface. By rolling on the wall the UAV can use its point of contact to stabilize the UAV and anchor itself in the presence of wind disturbances and creating a more certain trajectory.
The Kinematic Rolling Model used to create the rolling motion uses 3 virtual Denavit-Hartenberg frames controlled by 3 parameters to define the position and orientation of the UAV from a given frame on a surface, with z being the normal. By creating a trajectory with these parameters the UAV’s positional and rotational trajectories were calculated. After plugging the linear and angular accelerations into a Dynamic Model for a UAV, which was modified to include a normal force, the forces and required torques were found. This procedure was tested in both Matlab and ROS/Gazebo environments and found that the UAV was able to perform wall rolling. Though like other vehicles with nonholonomic constraints the UAV may be required to maneuver to reach a desired point.
To show possible methods of control of the UAV while wall rolling and in free flight, a Nonlinear Model Predictive Controller was developed with Feedback Linearization and Gradient Descent path planners. While each path planner was somewhat successful the Wall Rolling Feedback Linearization and Free Flight Gradient Descent path planners had drawbacks that hampered their usage.
Additionally the ability of the UAV to resist wind gust was simulated in the ROS/Gazebo environment. The UAV was found to be able to resist wind forces better than the UAV in free flight with comparable controllers. The ability to resist the wind was also dependent on the direction of the wind.
Little, Matthew, "A NONLINEAR MODEL PREDICTIVE CONTROLLER FOR A WALL-ROLLING FULLY ACTUATED UAV" (2021). Open Access Master's Theses. Paper 2001.