Open AccessAdaptive sliding‐mode‐assisted disturbance observer‐based decoupling control for inertially stabilized platforms with a spherical mechanism
Author(s) -
Tian Dapeng,
Wang Meiyu,
Wang Fuchao,
Xu Rui
Publication year - 2022
Publication title -
iet control theory and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.059
H-Index - 108
eISSN - 1751-8652
pISSN - 1751-8644
DOI - 10.1049/cth2.12296
Subject(s) - control theory (sociology) , gimbal , kinematics , decoupling (probability) , computer science , sliding mode control , inertial frame of reference , attitude control , workspace , observer (physics) , control engineering , engineering , robot , artificial intelligence , control (management) , nonlinear system , classical mechanics , quantum mechanics , aerospace engineering , physics
An inertially stabilized platform (ISP) is a gimbal used to hold a camera. It is essential for isolating the attitude sway during an imaging process. To make the platform more compact, the implementation of an ISP with a spherical mechanism has been proposed. However, this design introduces complex non‐linear coupling characteristics, significantly increasing the complexity of control. This study aims to solve this problem and present an algorithm to achieve high‐performance inertial stabilization control. To achieve this, kinematic and dynamic models were established, and the proposed control algorithm was then designed in three parts. Gravity compensation control was set up in the internal loop to counter the influence of unbalanced gravity moment. An adaptive sliding‐mode‐assisted disturbance observer (ASMADO) was also included in the joint space to decouple the influence of complex non‐linear characteristics on the platform. Further, a feedback controller was added to the workspace based on the kinematic model. This design simplifies the control algorithm for novel ISPs with a spherical mechanism. It effectively compensates for the complex non‐linear characteristics and enables superior inertial stabilization control. Experimental results show that the proposed method effectively decreases the motion isolation error for the line‐of‐sight of the camera compared to traditional control methods.