Autonomous sortie scheduling for carrier aircraft fleet under towing mode

Safe and efficient sortie scheduling on the confined flight deck is crucial for maintaining high combat effectiveness of the aircraft carrier.The primary difficulty exactly lies in the spatiotemporal coordination,i.e.,allocation of limited supporting resources and collision-avoidance between heterogeneous dispatch entities.In this paper,the problem is investigated in the perspective of hybrid flow-shop scheduling problem by synthesizing the precedence,space and resource constraints.Specifically,eight processing procedures are abstracted,where tractors,preparing spots,catapults,and launching are virtualized as machines.By analyzing the constraints in sortie scheduling,a mixed-integer planning model is constructed.In particular,the constraint on preparing spot occupancy is improved to further enhance the sortie efficiency.The basic trajectory library for each dispatch entity is generated and a delayed strategy is integrated to address the collision-avoidance issue.To efficiently solve the formulated HFSP,which is essentially a combinatorial problem with tightly coupled constraints,a chaos-initialized genetic algorithm is developed.The solution framework is validated by the simulation environment referring to the Fort-class carrier,exhibiting higher sortie efficiency when compared to existing strategies.And animation of the simulation results is available at www.bilibili.com/video/BV14t421A7Tt/.The study presents a promising supporting technique for autonomous flight deck operation in the foreseeable future,and can be easily extended to other supporting scenarios,e.g.,ammunition delivery and aircraft maintenance.

A Multirobotic Planning Based on Expert System

A robotic planning system using the technique of expert system for multirobotic coordi-nated motion with collision-avoidance has been developed.Its general architecture and theroles of its components are introduced in this paper.The task planning diagram of this sys-tem is also briefly explained.A mechanism for multirobotic planning has been proposed.Two examples of traffic control system,i.e.two-robot coordinated pathfinding system withcollision-avoidance have been demonstrated.In order to avoid the collision,some controlstrategies are applied.The results of this planning system are valuable and helpful for plan-ning the multirohotic coordinated motion with collision-avoidance.

Order-Preserved Preset-Time Cooperative Control:A Monotone System-Based Approach

This paper is concerned with order-preserved preset-time cooperative control of multi-agent systems with directed graphs.A novel monotone system-based approach is proposed to preserve the initial order of agents while guaranteeing the preset-time state agreement.Specifically,three different distributed controllers together with sufficient conditions are designed to realize leaderless consensus,leader-following consensus,and containment control,respectively.The proposed controllers facilitate preset-time deployment of agents in practical scenarios with collision avoidance requirement.Comparison studies through a numerical example are carried out to illustrate the effectiveness of the proposed controllers.

Design of ADS-B Simulator

In this paper, the ADS-B （automatic dependent surveillance-broadcast） used for manned aircrafts is chosen for aSee-and-Avoid sensor of UAV （unmanned aerial vehicle）, then GDL90 type is selected among three types of ADS-B. The serialcommunication data protocol which communicates between GDL90 and control panel of GDL90 is analyzed and tailored for theinterface of the GDL90 simulator here. This ADS-B （GDL90） simulator sends intruder information to FCC （flight control computer）of UAV for collision avoidance function.

Fast cooperative trajectory optimization and test verification for close-range satellite formation using Finite Fourier Series method

The process of formation reconfiguration for close-range satellite formation should take into account the risk of collisions between satellites.To this end,this paper presents a method to rapidly generate low-thrust collision-avoidance trajectories in the formation reconfiguration using Finite Fourier Series(FFS).The FFS method can rapidly generate the collision-avoidance threedimensional trajectory.The results obtained by the FFS method are used as an initial guess in the Gauss Pseudospectral Method(GPM)solver to verify the applicability of the results.Compared with the GPM method,the FFS method needs very little computing time to obtain the results with very little difference in performance index.To verify the effectiveness,the proposed method is tested and validated by a formation control testbed.Three satellite simulators in the testbed are used to simulate two-dimensional satellite formation reconfiguration.The simulation and experimental results show that the FFS method can rapidly generate trajectories and effectively reduce the risk of collision between satellites.This fast trajectory generation method has great significance for on-line,constantly satellite formation reconfiguration.