Accurate calibration of installation errors is of paramount importance for achieving high-performance in integrated navigation systems. In this paper, a self-calibration method for addressing installation errors in an integrated inertial/polarization/celestial navigation system is proposed. The method utilizes the information from gravity, polarized E-vector, and sun to establish constrained relationship between the multiple vectors. By employing a nonlinear least squares method, the installation parameters are iteratively determined. The effectiveness of the proposed method is demonstrated through comprehensive simulation tests. The results reveal that the method achieves improved accuracy and robustness in estimating installation errors.
The configuration of spacecraft thrusters directly affects the realization of precise automatic control and propellant consumption. At present, the design of thruster configuration lacks of theoretical guidance. Spacecraft carrying out complex space missions such as rendezvous and docking are often equipped with too many thrusters. This paper proposed a theoretical design method of thruster configuration for six-dimensional position and attitude control missions. Firstly, the mathematical description of thruster configuration is introduced. Then, a general design method of thruster configuration for six-dimensional control task is proposed. Finally, simulation of relative position and attitude control of rendezvous and docking task is taken as an example to verify the correctness and validity of the above method.
In this article, the optimal attitude tracking control problem of quadrotor unmanned aerial vehicle is investigated in the presence of actuator faults and uncertain perturbation. First, based on reinforcement learning and robust control theory, the robust learning-based optimal controller is designed. Then, according to the learning-based control strategy, the fault-tolerant control is further reconstructed to suppress the influence of actuator fault. Finally, the stability analysis based on Lyapunov is given to prove the stability of the closed-loop system. Simulation results verify the practicability of the designed controller.
In the future complex and dangerous combat environment, in view of the pilot’s difficulty in processing massive/incomplete information quickly, the lack of flight control ability, the conventional flight is difficult to deal with the battlefield environment and other problems, intelligent design ideas are introduced and the pilot intelligent assistant system is proposed. This paper first introduces the development history of pilot association system (PAS) at home and abroad, and puts forward the current design requirements. Finally, it systematically presents the challenges and key technologies in the overall architecture design, decision-making technology, human-computer interaction, autonomous learning and test verification.
Aero-engine is an important component of aviation equipment. Due to the special working environment and the poor temporality of fault diagnosis, it is difficult for aircraft maintenance personnel to make accurate fault diagnosis of aero-engine. To address this problem, this paper proposes an aero-engine fault diagnosis method based on an improved snake optimization algorithm (ISO) and a bidirectional long and short-term memory network (BiLSTM). The idea of balanced pool of EO algorithm is introduced in the snake optimization algorithm to build an elite pool to compensate for the low accuracy of calculation caused by randomly selected individuals, while the Lévy flight perturbation mechanism is introduced to enhance the SO’s performance of finding the best; the optimized parameters are substituted into the BiLSTM to reconstruct the model, train the fault data for prediction and output the results. In the simulation experiments, five failure modes are diagnosed with real monitoring data of a certain type of aero-engine and compared with the BiLSTM and SO-BiLSTM fault diagnosis models. The experimental results show that the ISO-BiLSTM fault diagnosis method proposed in this paper has better fault diagnosis effect compared with BiLSTM and SO-BiLSTM, and provides a new idea for aero-engine fault diagnosis.
