Min Zhang

The cooperative tracking of moving ground targets in obstacle environments by multiple fixed-wing Unmanned Aerial Vehicles (UAVs) has broad applications in both military and civilian fields. While extensive research has focused on tracking guidance laws and obstacle avoidance methods, existing approaches typically treat these functions separately. In contrast, this paper proposes a unified guidance design method that simultaneously addresses both target tracking and obstacle avoidance. The method develops a three-dimensional guidance strategy for fixed-wing UAVs under maneuvering constraints, considering the coupling of linear and angular velocities during cooperative tracking and obstacle avoidance. Comprehensive stability theory proofs are provided to ensure global asymptotic stability for the proposed method. To evaluate the effectiveness of the guidance law, simulations were conducted, including a comparative study with the artificial potential field method, where the proposed approach demonstrated superior robustness and coordination. Additionally, six-degree-of-freedom (6-DOF) simulations validated the applicability of the guidance law under realistic UAV dynamics, showing strong adaptability and realtime responsiveness.

Partition operating system conforming to ARINC653 is widely used in airborne to support application software integration. Under the two-level scheduling model for partition operating system, the demanding real-time requirements of airborne software are usually difficult to obtain effective deterministic guarantee, so it is very important to analyze the schedulability of the system. Judging whether the scheduling table can meet the real-time requirements of the process in the partition through the schedulability analysis algorithm is an effective means to ensure that all processes in the system complete the computing task within the specified time. Based on the method of operations research and the introduction of virtual process, a schedulability analysis algorithm for multi partition system is designed, and the numerical verification is carried out. The verification results show that the algorithm can accurately judge whether the scheduling table matches the process time attribute, give the qualitative analysis conclusion of whether the system can be scheduled, help the system integrator to verify the rationality of the scheduling table before the actual operation of the system, and reduce the risk of test and flight test. 机载领域普遍采用符合ARINC653标准的分区操作系统支撑应用软件综合化。在分区操作系统的两级调度模型下，机载软件苛刻的实时性要求通常难以得到有效的确定性保证，因此对系统进行可调度性分析显得至关重要。通过可调度性分析算法判断调度表是否能满足分区内进程的实时性要求，是保障系统中所有的进程在规定的时间内完成运算任务的有效手段。基于运筹学方法，通过引入虚拟进程，设计了一种多分区系统可调度性分析算法，并进行了数值验证。验证结果表明，该算法能够准确判断调度表与进程时间属性是否匹配，给出系统是否可调度的定性分析结论，帮助系统集成人员在系统实际运行前对调度表的合理性进行先期验证，降低试验和试飞风险。

This paper addresses the problem of network security for distributed filtering when subject to malicious cyber attacks. First, based on the Dempster–Shafer (D‐S) theory a protector for each sensor is proposed, that can decide whether to use data sent by neighboring sensors. Furthermore, a distributed estimator is proposed for the nonlinear system with the designed detector. Besides, a sufficient condition is presented for the stability of the estimator equipped with the designed protector when under cyber attacks. Finally, several numerical examples are presented to verify the proposed protection strategy's efficacy.

This article deals with cooperative target circumnavigation control strategy for a team of unmanned aerial vehicles (UAVs) when only range measurements are available. First, we propose novel guidance laws based solely on range measurements for tracking and cooperation. Then, convergence and stability of the proposed guidance laws are proved by a rigorous inference of mathematics. Moreover, an illustrative simulation shows that the controlled UAVs orbit around a target and maintain even spacing along the common circle, which confirms the performance of the proposed guidance algorithms.

An advanced chemical reaction optimization algorithm based on balanced local search and global search is proposed, which combines the advantages of adaptive chemical reaction optimization (ACRO) and particle swarm optimization (PSO), to solve continuous optimization problems. This new optimization is mainly based on the framework of ACRO, with PSO’s global search operator applied as part of ACRO’s neighborhood search operator. Moreover, a “finish” operator is added to the ACRO’s structure and the search operator is evolved by an adaptive scheme. The simulation results tested on a set of twenty-three benchmark functions, and a comparison was made with the results of a newly proposed hybrid algorithm based on chemical reaction optimization (CRO) and particle swarm optimization (denoted as HP-CRO). The finial comparison results show the superior performance improvement over HP-CRO in most experiments.

This paper provides a method of fixed-structure μ controller design with a novel particle swarm optimization (PSO) technique. The structured synthesis problem based on optimization is formulated and solved by a kind of constrained PSO algorithm which is relatively simple and without any new parameters added in the objective function. The experimental results tested on a set of 12 benchmark functions show that the proposed algorithm can outperform others in most cases. What is more, an air-to-air missile longitudinal channel control structure based on the proposed algorithm is studied and the simulation results are compared with other algorithms. The final comparison results also show the superior performance improvement over other algorithms.

One important problem for unmanned aerial vehicles (UAVs) in mission applications is to track ground targets automatically. A major concern is how to keep the tracking process stable and efficient while the motion of the ground targets changes rapidly. In this brief, a new guidance strategy for the ground target “Search and Capture” based on a virtual target is proposed. First, a virtual trajectory, which is composed of straight lines and arcs, is generated based on the motion of the target. The straight lines are used to capture, while the arcs are used to search, and switch between straight line and arc when some condition is met; second, we design a new guidance law based on line-of-sight (LOS) which makes a UAV to track the virtual target automatically. This new method solves the following three problems simultaneously: (1) The UAV always keeps a constant speed to track the target with changing velocity, (2) the generated trajectory meets the flight constraints of the UAV, and (3) the speed range of the ground target can be from the stationary to almost the maximum cruising speed of the UAV. Simulation results show that the proposed guidance strategy can achieve stable tracking for various motions of the ground target.

Over-flight and standoff tracking are the two typical modes of fixed wing unmanned aerial vehicle tracking ground targets. The guidance law of each mode is usually designed independently and thus shows different forms. In this paper, based on the constraints on unmanned aerial vehicle flight, a novel unitized guidance law, which is compatible with these two modes, is proposed. The stability of the guidance law is rigorously proved by a Lyapunov function, and the design of guidance parameters is discussed. Numerical simulation results show that the proposed guidance law can be used for automatically tracking the stationary and moving ground targets well, and also can switch between the two tracking modes smoothly.