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Lateral-profile planning:Three-dimensional-profile-based optimal trajectory generation

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Science China(Technological Sciences) 2022年第12期65卷 3057-3068页

作者： ZHANG YuanLong XIE Yu bao weimin College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China Science and Technology Committee of China Aerospace Science and Technology Corporation Beijing 100048China

The conventional re-entry guidance method considerably limits the maneuverability of hypersonic glide vehicles under pre-given angle-of-attack *** address this issue,based on a previous three-dimensional(3D)profile guidance method,we propose a lateral-profile-first 3D profile optimization design strategy to solve the trajectory generation problem under complex conditions involving multiple *** the traditional method,which prioritizes the design of the longitudinal drag acceleration profiles,our method first converted the re-entry flight constraints into a lateral flight corridor,generated the initial lateral profile via parameterization,and solved the 3D profile using the coupling relationship between the longitudinal and lateral *** design of the 3D profile requires simultaneous consideration of waypoints,no-fly zones,and altitude profiles;hence,a new 3D profile optimization design model was constructed,and a customized sequential quadratic programming algorithm was employed to solve *** advantages of the proposed method were demonstrated based on landing footprint results obtained using the lateral profile-first ***,simulation results based on the common aero vehicle-high-performance model verified the feasibility and effectiveness of the strategy.

关键词： hypersonic glide vehicle three-dimensional profile lateral profile-first planning optimal trajectory footprint

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Multi-constrained intelligent gliding guidance via optimal control and DQN

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Science China(Information Sciences) 2023年第3期66卷 214-229页

作者： Jianwen ZHU Hao ZHANG Sibo ZHAO weimin bao School of Aerospace Science and Technology Xidian University China Aerospace Science and Technology Corporation

In order to improve the adaptability and robustness of gliding guidance under complex environments and multiple constraints, this study proposes an intelligent gliding guidance strategy based on the optimal guidance, predictor-corrector technique, and deep reinforcement learning(DRL). Longitudinal optimal guidance was introduced to satisfy the altitude and velocity inclination constraints, and lateral maneuvering was used to control the terminal velocity magnitude and position. The maneuvering amplitude was calculated by the analytical prediction of the terminal velocity, and the direction was learned and determined by the deep Q-learning network(DQN). In the direction decision model construction, the state and action spaces were designed based on the flight status and maneuvering direction, and a reward function was proposed using the terminal predicted state and terminal constraints. For DQN training, initial data samples were generated based on the heading-error corridor, and the experience replay pool was managed according to the terminal guidance error. The simulation results show that the intelligent gliding guidance strategy can satisfy various terminal constraints with high precision and ensure adaptability and robustness under large deviations.

关键词： gliding flight optimal guidance velocity control deep reinforcement learning intelligent decision

Uncertainty analysis and probabilistic design optimization of hybrid rocket motors for manned lunar landing

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Science China(Technological Sciences) 2015年第7期58卷 1234-1241页

作者： ZHU Hao TIAN Hui CAI GuoBiao bao weimin School of Astronautics Beihang University China Aerospace Science and Technology Corporation

To obtain a conceptual design for a hybrid rocket motor(HRM)to be used as the Ascent Propulsion System in the Apollo lunar module,the deterministic design optimization(DDO)method is applied to the HRM *** on the results of an uncertainty analysis of HRMs,an uncertainty-based design optimization(UDO)method is also adopted to improve the design *** HRM design process,which is a multidisciplinary system,is analyzed,and a mathematical model for the system design is established to compute the motor performance from the input parameters,including the input variables and model *** input parameter uncertainties are quantified,and a sensitivity analysis of the model parameter uncertainties is conducted to identify the most important model parameter uncertainties for *** DDO and probabilistic UDO methods are applied to conceptual designs for an HRM to be used as a substitute for the liquid rocket motor(LRM)of the Ascent Propulsion *** conceptual design results show that HRMs have several advantages as an alternative to the LRM of the Ascent Propulsion System,including nontoxic propellant combination,small motor volume,and comparable functions,such as restarting and *** of the DDO and UDO results indicate that the UDO method achieves more robust and reliable optimal designs than the DDO *** probabilistic UDO method can be used to develop better conceptual designs for HRMs.

关键词： hybrid rocket motor deterministic design optimization uncertainty-based design optimization sensitivity analysis manned lunar landing

Uncertainty analysis and design optimization of hybrid rocket motor powered vehicle for suborbital flight

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Chinese Journal of Aeronautics 2015年第3期28卷 676-686页

作者： Zhu Hao Tian Hui Cai Guobiao bao weimin School of Astronautics Beihang University China Aerospace Science and Technology Corporation

Abstract In this paper, we propose an uncertainty analysis and design optimization method and its applications on a hybrid rocket motor （HRM） powered vehicle. The multidisciplinary design model of the rocket system is established and the design uncertainties are quantified. The sensitivity anal- ysis of the uncertainties shows that the uncertainty generated from the error of fuel regression rate model has the most significant effect on the system performances. Then the differences between deterministic design optimization （DDO） and uncertainty-based design optimization （UDO） are discussed. Two newly formed uncertainty analysis methods, including the Kriging-based Monte Carlo simulation （KMCS） and Kriging-based Taylor series approximation （KTSA）, are carried out using a global approximation Kriging modeling method. Based on the system design model and the results of design uncertainty analysis, the design optimization of an HRM powered vehicle for suborbital flight is implemented using three design optimization methods： DDO, KMCS and KTSA. The comparisons indicate that the two UDO methods can enhance the design reliability and robustness. The researches and methods proposed in this paper can provide a better way for the general design of HRM powered vehicles.

关键词： Design optimization Hybrid rocket motor Kriging model Uncertainty analysis Uncertainty-based designoptimization

Extended differential geometric guidance law for intercepting maneuvering targets

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Journal of Systems Engineering and Electronics 2018年第5期29卷 1046-1057页

作者： HUANG Jingshuai ZHANG Hongbo TANG Guojian bao weimin College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Aerospace Science and Technology Corporation Beijing 100048China

Without assumptions made on motion states of missile and target, an extended differential geometric guidance law is derived. Through introducing a line of sight rotation coordinate system, the derivation is simplified and has more explicit physical significances. The extended law is theoretically applicable to any engagement scenarios. Then, on basis of the extended law, a modified one is designed without the requirement of target acceleration and an approach is proposed to determining the applied direction of commanded missile acceleration. Qualitative analysis is carried out to study the capture performance and a criterion for capture is given. Simulation results indicate the two laws are effective and make up the deficiency that pure proportional navigation suitable for endoatmospheric interceptions cannot deal with high-speed maneuvering targets. Furthermore, the correctness of the criterion is validated.

关键词： missile guidance maneuvering target extended differential geometric guidance law capture performance proportional navigation

Trajectory generation of heat load test based on gauss pseudospectral method

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Science China(Technological Sciences) 2018年第2期61卷 273-284页

作者： ZHANG YuanLong LIU LuHua TANG GuoJian bao weimin College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Aerospace Science and Technology Corporation Beijing 100048China

A new trajectory generation for heat load test is proposed based on gauss pseudospectral method within limit range. Firstly,with multiple path constraints and flight task requirements taken into consideration, heat load parameters are introduced into the dynamics equations. In order to solve the problem of generating such a trajectory within limit range rapidly, the dynamics equations have been normalized by Earth related parameters. Secondly, since the gauss pseudospectral method is just employed to solve the discrete nonlinear programming problem, transformations are developed, which can relate the Lagrange multipliers of the discrete nonlinear programming problem to the costates of the continuous optimal control problem. In addtion, another approach of trajectory generation by tracking the given heat rate is also presented. Finally, simulation results with common aero vehicle(CAV-H) show that the trajectories obtained by both methods can well perform the heat load test with high stagnation heating rate and the large total aeroheating amount; meanwhile, gauss pseudospectral method is better than the compared one in the given range. Furthermore, the 3-D trajectory states and control variables, angle of attack and bank, which are generated by gauss pseudospectral method, can change smoothly.

关键词： glide vehicle trajectory generation heat load test gauss pseudospectral method

Fast and Adaptive Multi-Agent Planning under Collaborative Temporal Logic Tasks via Poset Products

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Research 2024年第2期2024卷 81-94页

作者： Zesen Liu Meng Guo weimin bao Zhongkui Li Deparment of Mechanics and Engineering Science College of EngineeringPeking UniversityBejing 0081 China Science and Technology Commission of China Aerospace Science and Technology Corporation Beijing 100048China

Efficient coordination and planning is essential for large-scale multi-agent systems that collaborate in a shared dynamic environment. Heuristic search methods or learning-based approaches often lack the guarantee on correctness and performance. Moreover, when the collaborative tasks contain both spatial and temporal requirements, e.g., as linear temporal logic (LTL) formulas, formal methods provide a verifiable framework for task planning. However, since the planning complexity grows exponentially with the number of agents and the length of the task formula, existing studies are mostly limited to small artificial cases. To address this issue, a new planning paradigm is proposed in this work for system-wide temporal task formulas that are released online and continually. It avoids two common bottlenecks in the traditional methods, i.e., (a) the direct translation of the complete task formula to the associated B點hi automaton and (b) the synchronized product between the B點hi automaton and the transition models of all agents. Instead, an adaptive planning algorithm is proposed, which computes the product of relaxed partially ordered sets (R-posets) on-the-fly and assigns these subtasks to the agents subject to the ordering constraints. It is shown that the first valid plan can be derived with a polynomial time and memory complexity with respect to the system size and the formula length. Our method can take into account task formulas with a length of more than 400 and a fleet with more than 400 agents, while most existing methods fail at the formula length of 25 within a reasonable duration. The proposed method is validated on large fleets of service robots in both simulation and hardware experiments.

关键词： hardware service system

Three-dimensional nonlinear coupling guidance for hypersonic vehicle in dive phase

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Science China(Technological Sciences) 2014年第9期57卷 1824-1833页

作者： ZHU JianWen LIU LuHua TANG GuoJian bao weimin College of Aerospace Science and Engineering National University of Defense Technology China Aerospace Science and Technology Corporation

Three-dimensional(3D)nonlinear diving guidance strategy considering the coupling between longitudinal and lateral motions for hypersonic vehicle is investigated in this *** constructs the complete nonlinear coupling motion equation without any approximations based on diving relative motion relationship directly,and converts it into linear state space equation with the same relative degree by feedback *** the linear equation,slide mode control with strong robustness is employed to design the guidance law,and 3D diving guidance law which can satisfy terminal impact point and falling angle constraints with high precision is obtained by substituting the previous control law into the origin nonlinear guidance ***,regarding lateral overload as the standard,hybrid control strategy which can take full advantage of the excellent characters of both bank-to-turn(BTT)and skid-to-turn(STT)controls is designed to improve the guidance accuracy ***,the results of CAV-H vehicle guidance test show that the algorithm can realize high accuracy guidance even if serious motion coupling exists,and has strong robustness to the path disturbances and navigation errors as well.

关键词： hypersonic vehicle 3D diving guidance coupling feedback linearization slide mode control hybrid control strategy

Numerical and experimental investigation of aerodynamic heat control of leading edge of hypersonic vehicle's flexible skin

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Science China(Information Sciences) 2022年第10期65卷 211-224页

作者： Xiaozhou Lü Chao YUAN weimin bao Guanghui BAI Fancheng MENG School of Aerospace Science and Technology Xidian University Science and Technology on Space Physics Laboratory College of Materials Science and Engineering Chongqing University of Technology

In this paper, a flexible skin inspired by the sudoriferous gland structure of human skin is developed for ultra-thermal protection of hypersonic morphing vehicles. The effect of different coolants and cooling flow rates on the cooling performance of the leading edge is studied using finite element analysis.A wind tunnel experiment is conducted at high temperatures with the heat flux Q = 700 k W/m2, and the results indicate the following:(1) the flexible skin can effectively reduce the surface temperature of hypersonic vehicles;(2) when using liquid water instead of argon as the cooling medium, the cooling efficiency of flexible skin performs better;(3) when liquid water is used as the cooling medium, the cooling effect peaks at a flow rate of 0.01 m/s, and further increasing the flow rate will not benefit cooling efficiency significantly;(4) the flexible skin can withstand extreme thermal environments, demonstrating its feasibility in applications of over-limit thermal protection for hypersonic morphing vehicles. This study aims at optimizing the cooling performance of the flexible skin for ultra-thermal protection. The proposed skin can overcome the heat-resistance limit of flexible materials with morphing properties, laying a theoretical and experimental foundation for its future applications in hypersonic morphing vehicles.

关键词： hypersonic vehicle flexible skin ultra-thermal protection micro-channel transpiration cooling

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