Department of Electrical and Electronics Engineering
Permanent URI for this collectionhttp://localhost:4000/handle/123456789/1925
Browse
3 results
Search Results
Item UAV Performing Level Turn Maneuver Under CG Offset: Backstepping Control Scheme(IEEE, 2023) Mukherjee, Bijoy K.When an Unmanned Aerial Vehicle (UAV) experiences uneven cargo loading or release, the center of gravity (c.g.) undergoes a lateral shift, leading to complex coupled and non-linear asymmetric dynamics. This poses significant challenges in controlling the UAV, particularly during lateral/directional maneuvers. To ensure the UAV's safety and stability, it becomes imperative to implement nonlinear control strategies. This study tackles the issue by first ad-hoc modeling the asymmetric dynamics and then effectively transforming them into strict feedback form. This transformation guarantees the desired level turn maneuver performance for a fixed-wing UAV, even when facing lateral center of gravity shifts. Subsequently, a backstepping control approach is developed to enable autonomous maneuver execution. Simulation results illustrate that the maneuver performance under lateral asymmetry closely resembles that of the symmetric case, demonstrating the effectiveness and need of the proposed control strategy in handling such scenarios.Item Asymmetric UAV Performing Pointing Maneuver Under Lateral CG Offset: An Adaptive Backstepping Control Approach(IEEE, 2023) Mukherjee, Bijoy K.This work addresses the complex issue of autonomously executing the maneuvers with fixed-wing Unmanned aerial vehicles (UAV), which can experience significant lateral center of gravity (c.g.) variations due to uneven cargo loading or release. The study establishes that the asymmetric flight dynamics of the UAV, caused by laterally shifted c.g., can be effectively represented in a block strict feedback form. Subsequently, an adaptive backstepping controller is proposed to enable the closed-loop system to adapt to c.g. variations. The controller’s stability is proven using Lyapunov’s method. To verify the effectiveness of the proposed control scheme, simulations are conducted involving pointing maneuvers with the Aerosonde UAV. The results demonstrate that the proposed scheme exhibits high resilience to lateral c.g. variations and achieves superior tracking performance.Item Lateral Maneuvering with a UAV Mitigating Lateral CG Variations: Modeling and an Efficient Adaptive Backstepping Control(World Scientific, 2024) Mukherjee, Bijoy K.In this paper, an adaptive backstepping-based control scheme is proposed to perform autonomous lateral maneuvers under significant lateral offset in the center of gravity (c.g.) position in a UAV. It is first shown that the coupled equations of motion arising from lateral c.g. shift can be simplified and cast in block strict feedback form making it amenable to a two-step backstepping control design. Useful nonlinear terms in the equations of motion are identified and retained in the backstepping design to ensure a less conservative control. Adaptation law is incorporated to dynamically adjust to changes in the c.g. position by adding an adaptive term to each step of the backstepping control. Lyapunov’s direct method and LaSalle’s invariance principle are applied to establish asymptotic stability of both tracking errors and errors in the c.g. estimate. To validate the effectiveness of the proposed control strategy, simulation results for horizontal turn maneuver are presented for the fixed wing Aerosonde UAV and maneuver performance is observed to remain highly insensitive to a wide range of lateral c.g. positions on either side of the fuselage centerline. Furthermore, a comparative control performance analysis is carried out against an ad-hoc model-based adaptive backstepping control scheme available in the literature and the results show significant performance enhancement in the proposed scheme. Along with the c.g. variations, the effects of steady crosswind are also investigated and the control formulation is modified to mitigate these effects too. Real-time control hardware in loop simulations are also provided in support of the real time viability of the proposed control.