This thesis explores innovative multifunctional designs for Unmanned Aerial Vehicles (UAVs) to achieve multimodal capabilities. Current robotic platforms often struggle in complex environments, necessitating a more adaptive and versatile approach. Drawing inspiration from nature, we propose a multifunctional appendage design for multirotors that enables the robot to perform aerial and terrestrial locomotion, coupled with perching. Our avian-inspired claw design allows UAVs to perch on horizontal bars and branches or walk on the ground. This design uses a fully passive mechanism to reduce weight and complexity.

Additionally, we introduce a novel crash-perching technique for fixed-wing UAVs, by employing wing morphing to allow crash-landings on vertical poles, followed by hugging with wings for secure perching. This fully passive multifunctional wing design provides a robust and efficient way to perch on various structures, achieving more than 70% of success rate when crash-perching on trees. We extend the capabilities of this hugging-wing robot by proposing bioinspired methods for climbing and unperching off vertical poles, offering enhanced versatility for inspection and exploration tasks. This approach integrates multifunctional wings and tail components for energy-efficient repositioning without fully disengaging from the perch.

In response to the need for collision resilience in UAVs, as well as for increasing the durability of crash-perching capable ones, we propose a tensegrity-based nose and shoulder joint, inspired by woodpeckers and bird wings. These design methods demonstrate a significant reduction in impact forces, by over 50%, compared to conventional foam planes, and yield outstanding resilience with minimal damage when subjected to hundreds of crash tests.