In recent years unmanned aerial vehicles (UAVs) have found a growing number of applications in various fields. Due to the increased UAV usage, the safety and security challenges posed by these UAVs also increase. A technology to detect and safely neutralize the threat-posing UAVs is required to overcome these challenges. As many of the offensive techniques to neutralize the adversarial UAV have the potential risk of collateral damage due to falling debris and projectiles, net capture can be explored as a viable alternative. Here, the capture net needs to be carried by a group of UAVs (pursuer UAVs) towards the adversarial UAV (target UAV) to aid in the mid-air capture. These net-carrying pursuer UAVs should be able to reach the target from any desired orientation and able to synchronize their velocities with the target's velocity, while also moving in a coordinated manner respecting the constraints imposed by the net being carried. Suitable guidance strategies are required to achieve this objective. Accordingly, this thesis aims to develop PN-based terminal orientation-constrained guidance strategies for the pursuer UAVs carrying a net for the mid-air capture of an UAV.
First, a PN-based all-aspect approach algorithm to approach a moving but non-maneuvering target from any desired orientation is developed and, this algorithm will then be extended to synchronize the velocity of the pursuer and the target. Then, the net-imposed constraints will be taken into the consideration to develop the guidance law for the coordinated movement of the net-carrying UAVs.