## 1 Introduction  
Nowadays, unmanned aerial vehicles (UAVs) are widely used in civilian and military applications. They are used for tactical reconnaissance, territory surveillance, target placement, and other military operations, as well as mapping, field monitoring, meteorological exploration, highway inspection, package delivery, and other civil applications. Their range applicability is due to their excellent design, which makes them efficient and cost-effective. They are also renowned for flying at varying speeds, hovering over locations, maintaining a stable position, and performing sophisticated maneuvers. Unfortunately, unanticipated events, such as actuator and sensor failures, can negatively impact their performance and raise safety concerns. Especially in multirotor UAVs, which use merely spinning rotors for thrust generation, actuator failure is a severe issue. Such causality potentially results in flight troubles, leading to a vehicle accident, resulting in a catastrophe and injuries to civilians. An effective way to mitigate this problem is to develop a fault-tolerant system that can endure a failure and continue to operate without significant performance degradation. The article by [PERSON] et al. [1] presents a complete survey on UAV fault-tolerant systems. Generally, two main components make up active fault-tolerant schemes. The first component is the fault diagnosis unit responsible for detecting, isolating, and identifying the fault. A second unit is a reconfiguration unit that employs an appropriate methodology that can compensate for the appearance of faults so that the UAV continues its flight mission or lands safely [2]. However, the reconfigurability of multirotor UAVs is possible whenever the UAV is designed so that it allows alternative actuator distribution to compensate for failed actuators. Researchers suggest several configurations of multirotor UAV layout to address the issue of actuator failure. The use of servomotors to convert the vehicle to reconfigurable ones by tilting rotors [3], changing the spinning direction of unidirectional rotors [4], the use of bidirectional rotors [5], and actuator redundancy that results in a bigger structure [6] are among suggested solutions. Although these solutions could regain control for the considered fault condition, post-failure mission execution capacities are limited to indoor and controlled environments. Howbeit, in densely populated areas where landing is impracticable, recovery operations are usually put through autonomous, obstacle-free, and time-optimal path planning to prerecord location and guidance by or landing on a moving vehicle by the vision-based detection technology of markers [7]. In such a situation, the UAV should be feasible for outdoor applications of such landing site searching operations that may require excellent maneuverability in flight with high perturbation. Taking the design flexibility of multirotor UAVs, appropriately arranging actuators at the design level allows compensation for failed actuators. [PERSON] et al. [8] proposed a method of determining an aircraft's capability to perform the desired maneuver in a nominal case. The authors represented the required moment as a time history of moments and directly overlaid it into an attainable moment set (AMS) envelope that shows the aircraft's maximum moment-producing capability. As a result, they infer that the existence of requested moment points outside the envelope indicates the inability to conduct the intended operation. However, an attempt involving improving the shroud and including the outside points is not mentioned. Hence, this work contributes to filling the gap by proposing a framework that can optimize a given multirotor UAV configuration to be actuator fault-tolerant and capable of performing desired recovery operation maneuvers. Hence, it provides flexibility in designing advanced failsafe operations that meet the environmental factors.