The expansion and locking process of aircraft folding rudder is a dynamic process of multi-load synthesis. The dynamic process is studied by simulation. The dynamic simulation model is established, considering aerodynamic load and friction action in the whole dynamic process. The influence of different aerodynamic load on dynamic process is analyzed by dynamically simulating the condition of obstruction, no-load and promoting aerodynamic load. By comparing the result of no-load expansion test with the simulation result of no-load condition, the accuracy of the dynamic simulation model is verified. Based on this dynamic simulation model, the friction work under different aerodynamic load condition is identified by using angular acceleration method and angular velocity method respectively from load and energy dimensions. The result of the study shows that the friction torque is affected by aerodynamic load. The friction work increases with the increase of aerodynamic promotion. The angular acceleration method and angular velocity method are both reasonable to identify the friction work. The research provides theoretical reference for engineering design and analysis of aircraft folding rudder.

The structure of S-shaped cable is complex. When S-shaped cable is separated at high speed, it has large deformation and complex nonlinear contact. The analysis of dynamic deformation and mechanical characteristics of S-shaped cable is one of the difficulties in engineering design. ABAQUS is used to establish the dynamic simulation separation model of separation cable. The dynamic deformation mechanism and mechanical characteristics of S-shaped cable are analyzed, and the correctness of the modeling method is further verified by the ground experiment. The influence of various sensitive factors, such as length, section diameter, tail length and separation speed of S-shaped cable is studied, which can provide analysis method and reference for engineering application.

In the aspect of evaluating UAV performance, in order to improve the disadvantages, such as strong subjectivity from the experts, too sensitive to data, the UAV capability modeling is proposed. It not only shields the heterogeneity and resource diversity of UAV from the upper layer, but also retains the important characteristics of UAV, which can present the UAV's capability to support the design of upper layer model and algorithm, and reduce the prior workload of the upper-level research and promote the development of related research. Furthermore, the differential entropy weighting method based on UAV capability is also proposed to evaluate the capabilities and comprehensive performance of UAV effectively. This method determines relative weight of each feature according to the feature vector corresponding to the maximum eigenvalue of the judgment matrix, and the final evaluation result is obtained through weighted calculation. Experimental results show that the method overcomes subjective bias from experts and increases the horizontal comparison among indicators to improve the stability of calculation.

The active aircraft defense problem with unknown attacking missile's guidance law is considered, and the one-way and two-way cooperation modes for a target aircraft and a defending missile are introduced. Cooperative guidance laws for the target and defender are proposed by using sliding mode control, which can enhance the measurement observability and meanwhile guarantee the successful defensive interception. A sliding surface is firstly constructed, considering both the requirements of estimation enhancement and successful interception. And then the one-way and two-way cooperative guidance laws are derived, by adopting the double-power reaching law and the state-feedback based exponential reaching law respectively. Compared with one-way cooperative guidance law, the two-way cooperative guidance law is optimized by introducing the cost function of control effort for the target and defender. Meanwhile, in two-way cooperation mode, the target aircraft can take the cooperative maneuver to help defender impact the attacking missile with less control effort. Simulation results show that the proposed cooperative guidance law can guarantee both the good measurement observability and the well defensive guidance accuracy.

The geometrically non-linear stiffness response of morphing aircraft structures is crucial for applications with large deformations. In order to study the nonlinear mechanical behavior of zero Poisson's ratio honeycomb structure with sinusoidal corrugated walls during large deformation in plane, a nonlinear mechanic model with consideration for geometric nonlinear is established based on nonlinear beam theory. It is verified by comparison with non-linear structural analysis with FEM. The stress-strain relationships with different parameters are obtained. The results show that the geometric nonlinear increases the equivalent stiffness with the increase in strain, and the stress-strain curves are greatly affected by corrugation ratio, thickness ratio, and inclination angle, but not by height ratio.

For multi-axle vehicle which use integrated design and integral body structure, rigid-flexible coupling virtual prototype model is established, which analyzes ride comfort of distributed driving multi-axle vehicle. On base of different connective with cab and body and different cab structure, ride comfort of vehicle is given with different load and different run case. Root mean square value of vibration acceleration of the truss structure cab with inclined support is effectively reduced. Comfort of the cab with no-connectivity top structure is better. Through optimize cab's structure form and top link shape, ride comfort of vehicle improves better on case of empty-load and full-load, which can satisfy the demands.

There are many capacitive loads in airborne equipment, the safety and stability of power supply are negatively affected by the surge at the moment of switch closing of power distribution facility. The causes and hazards of surge are analyzed, and the scheme of surge restrain is introduced. The parameters of transistor scheme are studied. The experiments of high and low ambient temperature and wide input voltage range are carried out, simulated and tested to verify the function and effectiveness of the design.

The hanging process is one of the key links in the Mid-Air retrieval of launch vehicle. According to the whole process of the launch vehicle tail cabin hanging in the air, the design of the hanging device based on the helicopter as the recovery platform is carried out. The hanging device includes tension sensor, load shedding device, overload protection device and the actuator in the end of the hanging device. Parafoil and parachute eject from the bottom of the tail cabin of launch vehicle. The hanging device can realize the hanging operation of the retrieval by hanging attached apex drogue on the top of parafoil. Through the simulation analysis of the hanging process, it can be seen that when the weight of the retrieval increases, the overload increases significantly. When the parachute retraction time increases, the load reduction effect is obvious

A product-oriented virtual test framework for structural strength of aircraft bodies is proposed, under which the classical elastic-plastic damage constitutive of materials and general finite element technology are developed, and a human-computer interactive virtual test platform for aircraft cabin structure is created based on the virtual test plug-in tool developed by Abaqus built-in Python software. Using the accurate confirmation technology of step-by-step inspection, the virtual/real test comparison from the specimen to the complex cabin is carried out to verify the feasibility of the virtual test of the cabin structure. The results show that the virtual test can simulate the load-bearing failure of the cabin structure with high fidelity, and the prediction accuracy of the ultimate load-bearing capacity is 4.6%.

Trans-media aircraft refers to a new concept special aircraft with both air flight capabilities and underwater submarine capabilities, which includes submersible aircraft and submarine-launched drones. Aircraft that can span multiple domains is focused on. Through literature research, this study elaborates on trans-media aircraft and their characteristics and applications, introduces in detail the development status of trans-media aircraft at home and abroad, analyzes the technical difficulties of achieving trans-media flight, and summarizes the key technologies required for trans-media aircraft. Finally, based on the investigation and the current development at home and abroad, the prospects of the trans-media aircraft are prospected and development suggestions are put forward.