Stable and high-precision localization is a prerequisite for realizing the cooperative autonomous navigation of unmanned ground vehicle (UGV).LiDAR simultaneous localization and mapping (SLAM) often fails to achieve the precise localization in scenarios lacking geometric features,such as corridors,tunnels,and deserts.Therefore,a leapfrog cooperative LiDAR SLAM degradation correction method is proposed for UGVs.This method is used to estimate the normal vector of each feature point in the current frame,and a LiDAR SLAM degradation detection algorithm is devised.When the degradation of environment is detected,the ranging information about two unmanned vehicles is utilized to correct the degradation in LiDAR SLAM.Finally,the locating results are further optimized in the pose graph.Testing on two self-built UGV platforms reveals that the proposed method achieves better mapping performance compared to the current famous LiDAR SLAM methods,demonstrating its significant capability to enhance the locating performance of LiDAR SLAM in degraded scenarios.

The control strategy of traditional tank bidirectional stabilizers is difficult to effectively deal with the coupling,nonlinearity and uncertainty in the new generation of all-electric bidirectional stabilizers,while the model-based nonlinear control can make full use of a priori information from the dynamic model of the system to enhance the control effect.Based on this,an electromechanical coupled dynamics model of an all-electric bidirectional stabilizer taking the actuator dynamics into account is established,and a nonlinear sliding mode control method based on neural network compensation is proposed.The sliding mode surface and the improved sliding mode robust control law based on hyperbolic tangent function are introduced to construct the nonlinear sliding mode control function,which can effectively eliminate the system oscillations and improve the system stability.Meanwhile,the multilayer neural network technique is deeply fused to accurately estimate the uncertainty in the system and make compensation for the feedforward,thereby avoiding high-gain feedback.It is rigorously demonstrated by the stability theory based on Lyapunov functions that the proposed control strategy can achieve the asymptotic stability performance of tank all-electric bidirectional stabilizer with continuous control inputs.A co-simulation environment and a semi-physical experimental platform are built.The superiority of the proposed control strategy is verified through a large number of comparative experiments.

Lubricating oil plays a pivotal role in engines due to carrying a wealth of information about the engine state,and is crucial for characterizing the faults of engine.The engine of an armored vehicle is studied,and a fault diagnosis method for the engine is proposed,which leverages the kernel linear discriminant analysis (KLDA) and an improved dung beetle optimization (DBO) algorithm to optimize a back propagation (BP) neural network.The dimensionality reduction of the acquired lubricating oil data is performed through KLDA,and the dimensionality reduced data is taken as input for the BP neural network.The DBO algorithm is then enhanced by integrating optimal Latin hypercube sampling method,weighting factors and Levy flight strategy in order to further optimize the key parameters of neural network.A fault diagnosis model is established to predict the faults in test data effectively.Experimental results affirm the proposed method’s efficacy in rapidly and accurately predicting the faults,providing a scientific basis for the maintenance and repair of engines in armored vehicles.

Addressing the uncertainty of dynamic model parameters in the terminal guidance phase of hypersonic gliding vehicles and the slow convergence speed of traditional reinforcement learning algorithm,an adaptive guidance algorithm based on reinforcement learning is proposed.The terminal guidance problem for hypersonic gliding vehicles under nominal conditions is converted into an optimal control problem,which is solved using the sequential convex optimization algorithm to generate a dataset of state-control pairs.The dataset is fitted through supervised learning to obtain a corresponding guidance model.The disturbances such as aerodynamic parameter deviation,uncertainty in control response delay coefficient,and state measurement noise are introduced,and the guidance model is further optimized based on the reinforcement learning framework through numerous interactions between the vehicle and the current environment.Numerically simulated results indicate that the proposed guidance method exhibits better robustness and accuracy compared to the supervised learning guidance method.

The high-speed electromechanical transmission(EMT) system for vehicle is characterized by a highly compact structure and high-speed components,leading to significant electromechanical coupling effects and susceptibility to resonance.This paper analyzes the electromechanical coupling inherent vibration characteristics of a series EMT system.An inherent vibration model of the system is derived,its natural frequencies and mode shapes are studied,and six typical vibration modes of the system are summarized based on the characteristics of each mode shape.The influences of high-speed operating conditions and electromechanical coupling effects on the system’s natural frequencies and mode shapes are investigated.The resonance speeds of the system within a wide operating speed range are studied using Campbell diagrams and modal energy method.The results indicate that the electromechanical coupling effects alter the low-frequency vibration characteristics of the system,and the high-speed operating conditions can significantly change the certain natural frequencies of the system.Both factors should be fully considered in dynamics modeling.The research of resonance speed provides a reference for the dynamic regulation and optimization of system.

As the potential applications and strategic value of unmanned ground vehicles(UGVs)in complex operational environments become increasingly prominent,the safety of their autonomous actions is of paramount importance.This paper proposes a system safety analysis method for UGV,which combines the system-theoretic process analysis(STPA)method and the Bow-Tie model.Focusing on the safety of teleoperated UGVs,the STPA method is utilized to identify the unsafe control actions(UCAs)within the UGV system and their associated latent risks.Subsequently,the Bow-Tie model is utilized to analyze the event chain from loss causation scenarios to potential accident consequences,thereby delineating the risk propagation and diffusion pathways.Ultimately,the active and passive safety stratified control measures are determined based on the Bow-Tie analysis,and the system safety management is realized through an autonomous safety controller.

Reforming the current manned tracked vehicles into the unmanned tracked vehicles is one effective way to develop the unmanned tracked vehicle.To this end,a data acquisition system is designed to collect the vehicle state and driver’s operation data.Based on the collected data,the driver’s steering behaviors during the tracked vehicle’s operation are clustered and analyzed based on the Gaussian mixture model(GMM),and a steering control behavior model is established.Based on different steering categories from GMM,a prediction model for the driver’s steering operation is trained by taking the running speed and steering angle deviation of vehicle as model inputs and the turning angle of hydraulic motor swinging arm as the predictive truth value of steering control.The proposed predsiction model is used for the statistical modeling and prediction of driver steering behavior in the in real cross-country environment.Experimental results show that the proposed steering control model can predict the driver’s steering behavior accurately.

Skid-steering wheeled vehicle has a wide range of applications. Understanding the impact of drive system on the vehicle driving and steering performance is the basis for forward design. In response to the design and analysis requirements of hydraulically-driven skid-steering wheeled vehicle, a coupling simulation model of hydraulic drive system and vehicle dynamics system is established based on the principle of the hydraulically-driven skid-steering wheeled vehicle systems. Combined with the specific vehicle parameters, the characteristics of the vehicle driving and steering conditions are simulated and analyzed to obtain the dynamic response characteristics of hydraulic driving system during vehicle driving. The simulated results of the model are verified through the actual vehicle. The results show that time-varying parameters such as road resistance, vehicle speed and driver operation have a great impact on the pressure of hydraulic driving system, which is strongly related to the dynamic steering resistance. The coupled simulation model can be used for the coupled simulation of vehicle motion state and hydraulic driving system state and the coupled analysis of hydraulic driving system characteristics and vehicle dynamics characteristics.

Unmanned surface vehicles (USVs) have high mobility,strong concealment,and extensive operational range,making them highly suitable for performing a wide array of tasks such as reconnaissance,anti-submarine warfare,search and rescue.Environmental perception technology,crucial for the operation of USVs,has attracted considerable attention.This paper conducts a survey on the development status of environmental perception technology for USVs at abroad,and define and analyzed the challenges in USV environmental perception through specific case studies.The current state of research on USV environmental perception technology is analyzed from the perspectives of both unimodal and multimodal perception,considering the sensory equipment utilized by USVs.Finally,the unresolved challenges in USV environmental perception technology are summarized,and its future development is prospected.

Time series matching technology is widely used in vehicle handling consistency evaluation.An evaluation method of vehicle throttle control action consistency based on segmented dynamic time warping (DTW) is proposed for the motion consistency evaluation of a coach vehicle in the process of cooperative driving.On the basis of the inconsistent number of sample data points in the cooperative control test of coach vehicle and the slope constraint of dynamic bending path, the traditional DTW rectangular search area is transformed into a parallelogram search area to reduce the area of the search area by changing the slope of search path, thus greatly reduce the calculation amount.Four groups of typical throttle action curves are selected to carry out 50 rounds of iterative experiments for verification, and the DTW distance matrix between the action curves of real vehicles A and B is calculated by segmented DTW method.A minimum deviation leveling method is used to combine the cluster objects for the actions of vehicles A and B, so as to complete the consistency evaluation of throttle action data.The experimental results show that the average matching accuracy of the improved DTW algorithm in each throttle action can reach 89.2%, which is about 3.2% higher than that of the single DTW algorithm, and the average matching time is about 92.45s, which is about 12.6% lower, thus verifying the feasibility and superiority of the segmented DTW algorithm in the consistency evaluation of throttle action.

Taking the external disturbances caused by the uneven road surfaces of marching tank gun control system (TGCS) and the unbalanced moment of tank gun elevation motion during TGCS operationinto consideration,a two-axis coupled two-degrees-of-freedom (2-DOF) dynamics model of the marching TGCS is established using the second kind of Lagrange method. In terms of the actual force and motion state of TGCS,an electromechanical coupling dynamics model is established for the marching TGCS, which is equipped with permanent magnet synchronous motors (PMSM) in the azimuthal and elevational direction drive system and the gear reduction gearboxes and roller screws in the transmission mechanism. A stable tracking controller for marching tank with finite-time convergence characteristicsis designed to quickly reject the effects of internal and external disturbances of the marching TGCS on the stable tracking of target. This design is based on a nonsingular fast terminal sliding mode (NFTSM) control law and a linear extended state observer (LESO). The stability precision and arrival time of TGCS for marching tank are calculated based on the stable tracking process for targets. The computational results are then compared with those obtained by utilizing traditional control methods under various operating conditions. The findings demonstrate that the proposed tracking controller exhibits rapid response speed,strong robustness against disturbances,and high tracking accuracy,thereby validating the effectiveness of the controller design.

To improve the mobility performance of off-road vehicles, this paper proposes a swing-cylinder hydro-pneumatic suspension system, which utilizes a high-pressure pneumatic principle and a back-pressure adjustable damping valve structure for the real-time adjustment of stiffness and damping characteristics. The vibration responses achieved by different stiffness control methods are comparatively analyzed using a single-wheel suspension model, and the fixed-point equations are derived for frequency-domain damping properties.A graded stiffness adjustment strategy and a frequency-domain hybrid damping control method are proposed. The effectiveness of the proposed method is verified through a single-wheel suspension dynamics model, and a high-mobility tracked vehicle dynamics model is established for the simulation analysis of a full-vehicle. The results show that the driving speed of off-road vehicle with the suspension employing the combined stiffness and damping control is increased by more than 25% compared with that of off-road vehicle with the traditional passive suspension under the actual road conditions of Kangzhuang, Yangbajing and Tuoli. These findings demonstrate the superior vibration suppression capabilities of the proposed control method, supporting the adaptive regulation of stiffness and damping characteristics of suspension system.

With the goal of addressing the challenges of real-time observation and localization of high-value military vehicles on the ground, a real-time algorithm for the detection and localization of military vehicles in aerial photography is proposed. An Armed_vehicle dataset for the detection of multi-type and multi-scale military vehicles in an actual combat environment in aerial photography is established. The detection accuracy reaches 85.82% and the detection efficiency is higher by introducing a large kernel attention (LKA）module into the lightweight neural network model YOLOX-Tiny and using the SIoU edge regression function. A monocular visual localization algorithm based on the visible light images from the unmanned aerial vehicles (UAVs) is proposed. The average target localization error is 3.69 m at a flight altitude of 100 meters. It indicates that the proposed algorithm can accurately obtain the geographical location of ground targets and has good comprehensive performance and application prospects.

The key parts of vehicle occluded due to complex backgrounds and variations in vehicle posture can not be accurately identified in images. A detection method based on partially deformable object graph convolutional network (PDO-GCN) is proposed for detecting the occluded key parts of vehicle. This method is founded on the rigid body structural relationships of vehicles, constructing a spatial association model between key parts on the 2D imaging plane based on PDO-GCN, and utilizes the detected results of visible key parts to estimate the locations of occluded ones. Experimental results demonstrate that the PDO-GCN model can effectively infer the complete vehicle structural information without the need for complex annotations, significantly improves the detection accuracy of occluded parts and fulfils the real-time requirements, thus showcasing considerable potential for practical application.

The formation keeping, reconfiguration and transformation functions of unmanned ground vehicle (UGV) formation systems are studied A hybrid leader-follower strategy is proposed to reduce the dependence on the leading vehicle and ensure the formation integrity. An independent obstacle avoidance function based on vehicle-to-vehicle (V2V) communication for the following vehicles is developed, and a formation node management system is designed manages the attributes of formation members in real time and supports the human-computer interaction. A dynamic extended trajectory planning method with cubic spline curve in three-dimensional space is proposed to generate the following trajectory and realize the obstacle avoidance by acquiring the position information of the front vehicle through V2V communication. The Frenet coordinate system is utilized to decouple the distance keeping and trajectory tracking problems, and the proportional-integral-differential (PID) controller and linear quadratic regulator (LQR) controller are used for longitudinal control and lateral trajectory tracking, respectively. The research results show that the performance of the proposed method can be quickly verifued in the simulation environment built, showing that the method has good performance. And the three functions of the vehicle formation system are verified by real vehicles, and the proposed method is confirmed to have good real-time performance through the stable maintenance of the distance between the vehicles, which is capable of realizing the effective following of the multi-vehicle formation, and shows a high degree of intelligent expansion and adaptability through the transformation of multiple formation shapes as well as the scenarios of members' joinning and departuring from the vehicle formation.

Mines,improvised explosive devices and roadside bombs have become serious threat to vehicle-mounted howitzers(VMH),and the blast wave generated by mine explosion can also cause damage to the cab structure of VMH and endanger the life safety of crew. Because of the significant difference in the response of the shock wave generated by the mines explosion at different positions at the bottom of the cab,numerical simulation of the response process of the cab bottom of VMH under six explosion-shock conditions was carried out. ALE algorithm was used to establish models of soil,air and explosive,and Lagrange algorithm was used to establish the models of cab and chassis of VMH,and the fluid-solid coupling algorithm was used to calculate the propagation process of the explosion-shock wave,as well as the dynamic response of the cab of VMH in this process. The changes of shock-wave pressure,acceleration and velocity at the bottom plate of the passenger's foot position were analyzed,and the maximum shock-wave pressure,acceleration and velocity at the bottom plate of the passenger's foot position were obtained,and the damage to the cab structure under the worst-case operating conditions was analyzed. The simulation results show that the shock wave generated by the mine will make the cab floor produce greater acceleration and speed,and the cab structure will be damaged. In this case,the passengers will be injured. It is necessary to add a protective structure for the cab of VMH. The simulation results can provide reference for the design of cab protective-structure of VMH.

In order to expand the application scope of folding wing UAV and extend the information acquisition ability of underwater platform,an underwater vehicle scheme of carrying UAV for dry launch was proposed by combining the advantages of UUV and UAV. In order to better evaluate the feasibility of launching UAV on the sea,the computational fluid dynamics simulation software StarCCM+ was used to simulate the launching environment of UAV on the sea,and the floating and launching process of UAV was simulated in the simulation environment. The air-bag scheme and the propeller scheme were designed respectively by referencing foreign design experience,and the different sea-conditions,different structural-parameters and attitude parameters were simulated and evaluated,and finally the launching process was simulated under the sea conditions. The results show that the UAV carrier in the state of zero buoyancy underwater can float stably on the water surface under different sea-conditions by the air bag scheme and the propeller propulsion scheme. In terms of UAV launch,the difference between the maximum sinking distance of the air-bag scheme in still water and sea conditions is about 2.5%,and the consistency is better than the error level of the propeller scheme of 30%. The average maximum sinking-distance of the vehicle during the launch of UAV is 0.28 m,which is lower than 0.4 m of the propeller propulsion scheme. In a comprehensive comparison,the air-bag scheme is more stable and reliable.

The trajectory design of air-launched vehicle is limited by many factors such as load,carrier safety,attitude control capability,etc. In order to solve the trajectory optimization problem under complex and multi-constraint conditions,an optimize method considering the crossing distance,maximum load and maximum control capability constraints was proposed. The crossing distance model and load calculation model of the aircraft and launch vehicle were established. By transforming the above model into process constraints and introducing them into the trajectory optimization problem,the pseudo-spectral method was used to solve the trajectory optimization problem,so as to realize the rapid optimization of the ascent trajectory of the air-launched launch vehicle under multiple constraints. On this basis,the typical parameters affecting the rocket crossing distance and maximum load in the trajectory design were sorted out,and the constraints between the parameters were analyzed. The simulation results show that the method can realize the trajectory optimization of the ascent phase of the air-launched vehicle under multiple constraints,and provide a reference for the development of the air-launched vehicle. From the point of view of reducing the maximum flight load of the rocket and improving the overall performance,the air-launched vehicle should be launched at a high altitude. After the launch,the angle of attack should be adjusted to the maximum at the maximum angular rate to ensure that the rocket can quickly pass through the dense atmosphere. At the same time,the crossing distance should be shortened as far as possible to avoid the acceleration of the rocket at low altitude.

To investigate the ventilated cavity flow characteristics of the vehicle water entry with gas jet cavitator,experiments of the vehicle water entry with gas jet cavitator were performed. The formation and development of the open cavity in the process of water entry were analyzed,and the effects of different ventilation rates and water entry angles on the cavity shape and gas jet length were discussed. The results indicate that there are different flow regions(i.e.,disturbance region,transition region,and the cavity develop region)during the formation of the open cavity,and it is related to the position of the vehicle. After the vehicle penetrates the air-water interface,the cavity surface(gas-liquid interface)exhibits the K-H instability significantly due to the viscous shear flow. The cavity collapse phenomenon was observed under the low ventilation coefficient. As the vehicle penetrates the water surface,the cavity diameter and gas jet length decrease gradually. The open cavity depth,cavity diameter and gas jet length increase linearly with the ventilation coefficient. The affect of the water entry angle is limited.

To solve the problem of optimal ascent trajectory design in case of small thrust-weight ratio of launch vehicle’s last stage,and send payloads into orbit with much less velocity loss and propellant consuming,a new trajectory design method based on more accurate line-gravity field was proposed by simplifying yaw program angle and co-states,which transfered the optimal thrust direction in vacuum flight into a two-point boundary value problem containing five constraints,and got the optimal trajectory by integrating motion equations. Furthermore,the initial values of iteration were analyzed according to launch vehicle’s flight features,and an estimation method of initial values of co-states and flight time was deduced,and a means and process of launch vehicle trajectory design in whole ascent flight based on linear-gravity field was put forward. The simulations show that this method generates the same results with the conventional method in situation of normal thrust-weight ratio,and pitch program angle varies nearly linearly. In situation of small thrust-weight ratio,this method generates much less velocity loss,saving 2.9% and 2.1% propellant compared with the conventional method and iterative guidance respectively,and pitch program angle varies non-linearly. This method is of good convergence and optimization effect,and can be well applied in trajectory design of small thrust-weight ratio and launch vehicle’s whole ascent flight. This method can also supply a new means of online trajectory planning,etc.

The design of trajectory in boost phase of the lift vehicle is facing the difficult problem of carrying capacity optimization under the coupling condition of multiple constraints in the complex atmospheric flight environment. It is necessary to design the program angle of the boost phase to maximize speed of entering orbit under the constraints of stages separation height,angle of attack limit,height of the orbit entry point,etc. In order to find an engineering design method to quickly solve this problem,taking the three-stage solid launch vehicle as the research object,the multi-constraint trajectory design method in boost phase of the lift vehicle was put forward. The design variables were formulated by designing the flight trajectory mode of the boost phase,and the constraint conditions of the boost phase were determined. The optimization model aiming at the maximum orbital speed under multi constraints was built. By analyzing the coupling relationship between design variables and constraints,an efficient optimization process was formulated. The optimization initial value was determined by Newton iterative method,and the optimization simulation was carried out by sequential quadratic programming method. The optimal solution satisfies the multi-constraint conditions,and the orbit entry speed increases by 3.1%,which verifies the correctness of the trajectory design method and the effectiveness of the optimization process. The multi-constraint trajectory optimization design method in boost phase of lift vehicle has strong engineering practicability. The modeling method and optimization process can offer reference for other optimization problems.

In order to analyze the influence of power station vibration on a high-precision wheeled weapon launch vehicle,the structural layout of the launch vehicle was analyzed. The chassis suspension structure,the flexible characteristics of tire and mounting bracket,and friction effects of locking mechanism were considered,and the force analysis was carried out. A flex-rigid multi-body dynamics model of this vehicle was established. Vibration load was applied according to the data of power station vibration test,and the verification model was built. Transmission characteristics of power station vibration were simulated,and the aiming precision of launcher under composite impacts of servo adjustment of launcher,the flexibility of bracket and tyres,and power station vibration were analyzed. The simulation results show that vibration of power station was absorbed and attenuated during transmission. The power station and bracket have obvious effect on vibration attenuation. The residual vibration can affect the aiming precision of launcher after the vibration of power station transmitting to the launcher.

In order to accurately reflect the dynamic characteristics,optimize the comprehensive performance and obtain better control tracking effect for tank servo systems,the mathematical model of the nonlinear dynamics of the coupled load between the axles,the mathematical model of the drive end of the azimuth subsystem,and the mathematical model of the drive end of the pitch subsystem,were established. Simulation software Mworks based on Modelica language was used to establish the simulation model base of the tank servo system,and the simulation research was carried out. The results show that the model based on Mworks can accurately simulate and verify the tank servo system,and it can meet the requirement of stable precision of the tank servo system. Based on MWorks,the tank servo system can be intuitively simply modeled,and the relationship between modules directly reflects the relationship between physical quantities. The established comprehensive dynamic model of the tank servo system has good repeatability,which improves the modeling efficiency.

In order to study the supercavitating flow characteristics of series vehicles in shallow water,the continuity equation and momentum equation of the mixed phase of air,water and steam were established by using the Volume of Fluid multiphase flow model. The supercavitating flow field of series vehicles in shallow water was numerically simulated,and the effects of water depth and vehicle spacing on supercavitating flow were studied. The results show that,in the motion course of vehicles with the forward and backward series,the supercavitation will form,and the initial shape and outline of the bubble are similar,and the leading waves will be excited on the free surface. In shallow water,there will be air above the supercavitation,but with the increase of water depth,the air above the supercavitation is no longer involved in the cavitation. With the increase of the spacing between vehicles,the contour of supercavity becomes smoother in the full development stage. When the distance is greater than 5 times the diameter of the vehicle,there is no significant difference in the supercavity profile of the series vehicles with different spacing.

The ionization reactions were divided into three sections according to different reaction mechanisms,and they were introduced into DSMC with different criteria for the occurrence of chemical reactions. The influence of ionization reaction on the aerodynamic characteristics of hypersonic vehicle was studied,and different calculation results derived from different flow fields composed of different species were compared. Most of the electrons concentrate at the head of the vehicle in the flow field. The flow field temperature and the heat flux get a sharp decrease after introducing ionization reactions. The effects of different ionization reactions on the characteristics of the flow field were compared. The associative ionization is the basis of all ionization reactions,and the electron-excitation ionization can promote the formation of free electrons in the flow field,but the charge exchange reaction do just the opposite,whereas both of the two kinds of ionization can weaken the heat flux on the surface of the hypersonic vehicle.

In order to accurately describe the barrel stabilization system of a moving tank,the united simulation model based on multi-body dynamics and hydraulic adjustment systems was built by using multi-body dynamics software RecurDyn and hydraulic system simulation software AMESim. Based on multi-body dynamic analysis software,a multi-body dynamic model of the moving tank was built,and a PID hydraulic control system of vertical stabilizer was built based on professional hydraulic system simulation software. The united simulation of the stability model of the moving tank was carried out through the interface block. The scheme of vertical stabilizer on single side was compared with that of stabilizer on symmetrical arrangement. The calculation results show that this united simulation model can accurately simulate the tank stability system,and it meets the accuracy requirements of stabilization system of tank. The symmetrical arrangement can improve the proposal stabilization effectively. The research offers reference for improving the stabilization of tank under the condition of high mobility.

To solve the problems such as uncertain configuration,multiple target orbits requirements and huge workload of optimization design of launch vehicle,a simplified optimal trajectory design algorithm was proposed. By simplifying the dynamic equation and control variables,the non-linear programming problem which is difficult to be modeled due to uncertain configuration,was transformed into a simplified algorithm which is suitable for multiple launch configurations and convenient for optimization. Different orbit-mission requirements of launch vehicle were analyzed,and all the missions were classified according to whether there was a glide segment,and a trajectory splicing method for different missions was proposed. The actual flight curves of two kinds of launch vehicles CZ-3B and Falcon9 with different configurations were fitted by the simplified trajectory design algorithm. The simplified algorithm is correct.

To build the more perfect firing dynamics simulation model of gun,the elevating mechanism gear wheel and gear arc for infantry combat vehicle were taken as object,and the double tooth contact coefficient of elevating mechanism was calculated and combinded with the whole ADAMS firing dynamics model. The contact coefficient was joint in the ADAMS firing dynamics model. The gear wheel and gear arc were defined as flexible bodies,and the finite element model of the gear wheel and gear arc was built by applying ANSYS software,and the original tooth position was set to double-tooth meshing zone. Pure penalty method was adopted,and then the contact characteristics such as contact force,contact clearance and contact sink were calculated. Combined with contact force formula,the double tooth contact coefficient was calculated. The infantry combat-vehicle rigid-flexible firing dynamic model was built based on the contact coefficient base data,and the auto-gun firing process on the move was analyzed. The construction dynamics response of four middling road conditions in the second speed was studied,and the influence of dynamic clearance on gun was researched. The calculated contact-stiffness-coefficient can effectively reflect the dynamic characteristics in the launching process on the move,and the result can offer basic data for achieving the high-precision hit ability and increasing the firing precision.

To study the effect of the change of general parameters on the motion stability of autonomous underwater vehicle’s turning performance,the sensitivity of general parameters of autonomous underwater vehicle was studied. The 6-DOF motion equations were established,and the three-dimensional motion model of underwater vehicle was built,and the turning pattern was numerically simulated by use of MATLAB/Simulink model,and the turning motion regulation was obtained. Taking turning performance of underwater vehicle as an example,the effects of general parameters such as buoyancy,the distance between gravity centre and buoyancy centre,the downward displacement of gravity centre and the lateral displacement of gravity centre on the turning velocity,turning angular-velocity,turning depth and turning space motion of underwater vehicle were numerically calculated and analyzed. The results show that the effect of buoyancy variation on motion performance of underwater vehicle is small; the variation of the distance between gravity centre and buoyancy centre can cause the change of pitch angle. The increase of downward displacement of gravity centre can improve the motion stability,but the increase of the lateral displacement of gravity centre can reduce the motion stability.

To meet the requirement of adaptability of the ascent guidance of combined-cycle vehicle under multi-constraints,a closed-loop guidance method based on receding horizon pseudo-spectral optimization was studied. The guidance was carried out under the framework of the hierarchy-structure receding horizon optimization,which applied segmented pseudo-spectral method to generate the online real-time command,and the command can be updated iteratively with the state feedback. The mesh update strategy was introduced to improve the efficiency of the algorithm,and the guidance cycle was adjusted adaptively based on real-time state deviation. Simulation results show that the proposed guidance method is feasible,and it can effectively suppress the influence of model parameter uncertainty and external interference. The guidance accuracy meets the mission requirements. The calculation time is in the order of hundred milliseconds. Thus,the method is of certain value for engineering application.

To study the effect of technical conditions of the breechblock and anti-recoil mechanism on armored-vehicle firepower system(AVFS)and precisely judge the latent fault caused by the variation of technical conditions,the cloud theory was applied to analyze and process the test data of technical condition parameters. The change-rule model of all the test data in the whole test period was built,and the cloud model was applied to predict the change of the condition parameters in the short term. Based on the cloud transformation method,a plenty of technical condition parameters of AVFS were transformed into multiple qualitative cloud concepts to simplify the test data categories. A series of cloud-fault reasoning rules of technical condition parameters were put forward through the association-rules mining,and the credibility of corresponding reasoning results was calculated. The combination-rule generator was established on the basis of cloud reasoning,and a large number of samples were applied to train and improve the generator. The stable fault-prediction results whose credibility was greater than the set threshold were obtained. The instance indicates that the technical condition prediction-method based on cloud theory and fault reasoning generator can use non-equal time interval test data of technical condition parameters to accurately assess the technical condition and accurately diagnose the fault type.

In order to assess the vulnerability of typical tank under HEAT,the damage tree diagram of tank was established by analyzing tank external structure and internal key components,and the typical tank was described by computer. Based on the penetration mechanism of jet and the principle of tank damage,the vulnerability evaluation model of tank under HEAT was established. The vulnerability of typical tank under HEAT from front and left was calculated. The result shows that,the average damage probability(0.16)of M-level in front of the tank is greater than that of the F-class(0.06)and K-class(0.02),and the average damage probability(0.22)of F-level on the left side of the tank is greater than that of the M-class(0.21)and K-class(0.14). The tank vulnerable area of the left surface is larger than that of the front.

The separation of capsule and vehicle plays a significant role during water-surface separation process,which affects the initial motion attitude of vehicle after separation. Aiming at this problem,the forces on the capsule and the vehicle were analyzed,and the strip theory was used to set up the hydrodynamic model. By using MATLAB,the model of the separation of capsule and vehicle on the water surface was built,and the changing progress of capsule and vehicle during the process of separation was showed. The reliability of the model was proved by comparing simulation results with tank experiment results. The simulation results show that the absolute value of the pitch rate decreases during the separation process on water suface.

To study the planning approach of low-altitude rapid ascent trajectory for air-launched near-space vehicle,the ascent trajectory was divided into four phases such as dropping phase,the first powered phase,gliding phase and the second powered phase. To climb rapidly after the dropping,the maximum normal load was applied during the first powered phase. In order to satisfy the terminal constraints of the second powered phase,the time-varying longitudinal control variable was parameterized as a piece-wise polynomial,with a lateral energy management scheme based on triangle function. A parameter-programming problem with multiple phases and constraints was formulated,and the modified particle swarm optimization was employed to solve it. The simulation results show that the constraints of load,control and separation were well satisfied; this method can provide reference trajectories with high accuracy and computational efficiency for different constraints.

In order to accurately describe the gun pitch system of a moving tank,the dynamic model of multi-body system of a marching tank was established by the dynamic software RecurDyn. The credibility of the model was preliminarily verified by simulation and experiment. The dynamic modeling and analysis of the gun pitching system with the permanent magnet synchronous motor(PMSM)as the actuator were carried out,and the mathematical model of the gun pitching system was established. On this basis,aiming at the problem of poor controlled by the traditional three loop structure,the adaptive robust controller of the gun pitch servo system and the disturbance observer for feedback compensation of the system disturbance were designed. The stability analysis of the controller was completed,and the control model of the gun pitch system was designed. Finally,the co-simulation of the tank pitching system was realized through the interface module. The simulation results show that the multi-body system dynamic model established in this paper is reasonable,and control strategy of the designed gun pitch servo system has good step response,aiming stability,strong robustness and anti-interference ability.

目前坦克火炮控制系统主要有电液式和全电式两种控制方式。国外第三代坦克均采用全电式火炮控制系统结构。我国的步兵战车也采用了全电式火炮控制系统结构。对比分析了国内外坦克火炮控制系统技术发展现状,提出了坦克火炮控制系统技术发展趋势,分析了坦克火炮控制系统的关键技术并对开展坦克火炮控制系统技术研究提出了建议。

火炮控制检测系统各检测信号大多含有随机干扰,利用卡尔曼滤波可对检测信号进行实时递推滤波。以某型坦克火炮控制检测系统为实例,将噪声简化处理为白噪声,通过建立参数的运行模型和观测模型,完成了卡尔曼滤波在火炮控制检测系统中的应用。

分析了某坦克简易火控系统的性能特点和各种可能的射击方法。采用各种射击方法时,弹着散布、瞄准误差等随机误差对方位向命中概率的影响基本相同,因而忽略瞄准误差等的影响,只考虑理想散布中心与目标中心的关系,以此来分析各种射击方法的射击精度。通过对各种射击方法进行精度分析,可以得出结论:使用火控系统自动测量目标角速度并进行射击,是对运动和静止目标射击的基本方法,在火控系统能够正常工作时必须首先采用。

为满足部队对新装备不解体检测的需求,尽快形成新装备维修和综合保障能力,利用LabWin-dows/CVI虚拟仪器开发工具,高度集成各种测量和控制硬件实现了某型坦克火控系统火控计算机及传感器等各部件的检测。与传统的检测系统相比,简化了硬件设计,实现了测试信号的实时采集与处理,并具有较强的人机交互功能。

针对坦克装甲车辆火炮控制系统,设计了以数字信号处理器为控制核心,以第三代智能功率模块(IPM)为逆变器,以永磁同步电机(PMSM)为驱动电机的数字交流炮控伺服系统。系统采用F28X系列DSP控制器,它不但可提供强大的程序容量和运算速度,而且把马达控制中常用的硬件电路固化在芯片中,完全可以满足对电动机控制愈来愈高的性能要求。系统的总体解决方案为以电传控制系统为基础,配以陀螺仪组、传感器及必要的机械传动装置,结果表明,整个驱动系统可靠性高,控制灵活。