In response to the current reality that cryogenic liquid launch vehicles have become the mainstay of space missions and the urgent need to enhance personnel competency, this study proactively addresses the training requirements of launch sites for the upcoming universal ground-based testing, launch, and control systems. By fully considering scenarios such as normal testing and launch procedures, troubleshooting under abnormal conditions, and emergency response operations, research, design, and development of a simulation and training system for cryogenic liquid launch vehicle testing and launch procedures are conducted. This system thoroughly analyzes the universal characteristics of the product and aligns with the training needs of launch sites for the soon-to-be-deployed universal ground-based testing, launch, and control systems. It develops hardware equipment and testing software consistent with actual products, covering all phases of testing operations across launch site systems. It supports comprehensive, full-process operational training for all systems and positions, fully meeting the training needs of personnel involved in cryogenic launch vehicle testing and launch operations. The system is capable of fostering a more technically proficient testing and launch team, thereby comprehensively supporting the foundational capacity building of a leading spacefaring nation.

To address the limitations of existing methods for underwater unmanned vehicle (UUV) motor fault diagnosis, which rely on manual feature extraction and do not fully leverage the potential of intelligent diagnosis, a two-stream CNN-LSTM fault diagnosis model is proposed. The model employs convolutional neural networks as feature extractor, which can learn the low frequency trend and high frequency detail features of the original signal without complex pre-processing steps, making real-time motor status monitoring possible. Afterwards, the classifier based on the long short-term memory network uses these features to explore temporal dependencies and identify motor faults. Experiments are conducted on a self-constructed UUV motor fault simulation platform, and the performance of the model is validated by setting multiple speeds and load conditions. The results show that this method can efficiently diagnose six typical states in UUV motors and achieve an average diagnostic accuracy of 97.22%. These findings demonstrate the model's effectiveness and robustness in UUV motor fault diagnosis.

The rolling screw transmission mechanism is a key transmission component of the servo mechanism. Monitoring its operating state is crucial for the normal operation of the servo control system. Currently, there are still difficulties in the state monitoring of rolling screw transmission mechanisms, such as low integration and wiring difficulties. A multi-parameter wireless micro-nano sensing monitoring system for rolling screw transmission mechanisms is designed. The sensing module, MCU module, wireless module and power management module are integrated in this system, which can be integrated with the nut of the rolling screw transmission mechanisms directly and flexibly, improving integration and reducing wiring complexity. The sensing module contains three types of MEMS sensors for temperature, acceleration, and acoustics to meet the condition monitoring requirements of multi-point distributed and multi-parameter sensing on the surface and interior of the nut. This system has advantages of small size, easy installation, flexibility and high integration, effectively monitoring the working state of rolling screw transmission mechanisms.

At present, with the complex and changeable game environment, deep learning models such as deep convolutional neural networks are introduced to assist in improving personnel's cognition and decision-making level of the game situation. However, when deep learning is introduced into game situation understanding, it also introduces data uncertainty and cognitive uncertainty in artificial intelligence, which leads to problems such as divergence of artificial intelligence prediction results. Key elements of uncertainty in the measurement process of game situation understanding are decomposed, extracted and measurement modeling constructed based on the measurement uncertainty evaluation method. The experimental results show that the physical measurement method based on GUM can effectively measure and evaluate the cognitive uncertainty of game situation accurately and efficiently. Finally, based on Monte Carlo method, the proposed new qualitative measurement method of game situation cognition uncertainty is verified, which shows the accuracy and applicability of the proposed method.

Numerical investigation on the characteristics of a two-dimensional, mixed-compression inlet with various leading edge bluntness is presented. Effects of leading edge bluntness on the self-starting ability, aerodynamic performance of the inlet at design and off design operations are acquired. Results indicate that, with the increase of blunted radius, the self-starting ability and mass flow capture of the inlet are deteriorated, the backpressure tolerance capability and critical total pressure recovery coefficient goes down, while the drag coefficient rises obviously. 5% decrease of mass flow ratio is observed while the backpressure tolerance and critical total pressure recovery coefficient drop off at least 8.5% for the design operating point. Complex shock wave interference pattern forms due to the oblique shock waves from the external compression of the inlet intersecting the bow shock wave produced in front of the leading edge with the variation of freestream Mach number and the angle of attack. Diminution of flow separation in the inner side of the inlet lip is observed with the increase of blunted radius at a high Mach number condition. As the angle of attack rises, the influence of the bow shock wave induced by the blunted leading edge on the performance of the inlet is found to be weaken.

This article takes the real-time intelligent reconnaissance of the American "Black Swift" hypersonic intelligent aircraft as an example to analyze the demand for strong real-time, high-energy efficiency intelligent computing of typical intelligent hypersonic vehicles. On this basis, it analyzes in detail how to build a strong real-time, high-energy efficiency intelligent computing system for intelligent hypersonic vehicles from three levels: intelligent model lightweight, software and hardware collaborative compilation and optimization, and ultra-heterogeneous integrated computing hardware. Furthermore, a system integration example is provided to illustrate the practical application of these principles. In the future, with the loading of the strong real-time, high-energy efficiency intelligent computing system, intelligent hypersonic aircraft will be more autonomous, reliable and capable of group collaboration, and will drive the intelligent upgrade of aerospace cross-domain flight and global rapid transit.

Overload changes the internal ballistics of the motor and the erosion of the thermal protection structure, which increases the coupling degree between engine design and flight trajectory design. Conventional solid rocket overall-motor discrete design is difficult to fully consider this coupling relationship. By studying the coupling relationship between internal ballistics, external ballistics and thermal protection structure, an internal ballistics model and a thermal protection structure model considering flight overload are formed. An integrated simulation method based on internal ballistic model, external ballistics model and thermal protection structure model is established to achieve accurate prediction of internal, external ballistics and thermal protection structure erosion under overload. The calculation results show that under overload, the pressure of the motor increases, the altitude and the local flight path angle of the shutdown point increases, while the flight speed remains basically unchanged. The total mass of the thermal protection structure increases and the thermal protection structure thickness of the nozzle changes, requiring strengthened thermal protection. The integrated simulation correctly predicts the changes of internal and external ballistics under overload, laying the foundation for the joint design of internal ballistics, external ballistics and thermal protection structure, which can improve the integration degree of solid rocket overall-motor design.

In order to respond to the booming development of the commercial satellite launch service market, while effectively utilizing the launching capacity of domestic satellite launch missions and the available envelope space within the payload fairing, and to provide more cost-effective launch services for satellite users, the Long March-2D launch vehicle has developed a main satellite-disk mounting configuration and a tandem-parallel-side hybrid configuration for micro satellite piggyback and multi-satellite rideshare launch missions. This has been applied in the launch missions of the Chinese Hα Solar Explorer (CHASE) and Qilu-2/3 satellites. The feasibility and efficiency of the configuration layout design have been validated through flight tests, achieving effective integration and flexible deployment of satellites with different installation methods. As a mature liquid launch vehicle of conventional propellant, the application of rideshare mode further enhances the mission adaptability of the Long March-2D launch vehicle and can reduce the launch cost of a single satellite.

The guidance system, a core subsystem of launch vehicles, is crucial for the successful launch. Perturbation guidance, as the primary guidance method for domestic rockets within the atmosphere, relies on the design efficiency and precision of guidance parameters to determine the overall system performance. Traditionally, the parameter design is carried out by designers through extensive trial calculations and experience-based adjustments, resulting in low efficiency and high costs. To address this issue, an automatic optimization method for perturbation guidance parameters based on adjoint sensitivity and the Adam gradient descent algorithm is proposed. By constructing a point-mass dynamic model of the launch vehicle, the guidance parameter design is transformed into a constrained optimization problem. The adjoint sensitivity method is employed to efficiently compute the gradient of the objective function with respect to parameters, while the Adam algorithm adaptively adjusts the learning rate to achieve parameter auto-tuning. A two-stage launch vehicle is tested under random wind field disturbances. The perturbation guidance control parameters are optimized using a cost function that combines trajectory tracking errors and terminal range deviations. Simulation results show that the compared with the traditional manual tuning method, the proposed method can quickly find suitable control parameters. It provides an efficient and precise solution for the design of perturbation guidance parameters in launch vehicles, significantly reducing simulation time and design costs. The method also offers engineering reference value for improving the optimization efficiency of complex dynamic systems

In order to study the locking-swing phenomenon and swing suppression method during the pyrotechnic driving-locking process of aerocraft door, an explicit dynamic finite element simulation is conducted for an aircraft door opening-locking mechanism driven by a pyrotechnic actuator. The pyrotechnic driving-locking process of the mechanism is simulated in stages and verified compared with the pyrotechnic driving test. The locking-swing phenomenon and mechanism of the door are revealed, and swing suppression method is proposed. The research shows that the simulation method is effective, reproducing the experimental locking-swing phenomenon, and the swing angle is basically consistent with high-speed photography results. A single-freedom torsional vibration model can be used to estimate the swing characteristics of the door. Increasing the stiffness of the actuator or supported structure, or enhancing the door goose neck, has limited effect on swing suppression. Weakening the door goose neck, making it under plastic deformation during door swing, can effectively suppress the swing angle, and meet the demand for pyrotechnic opening of the door in emergency situations.