LQR Integrated with Fuzzy Control for Aerial Refueling Autopilot

Linear Quadratic Regulator （LQR） is modem linear control that is suitable for multivariable state feedback and is known to yield good performance for linear systems or for nonlinear systems where the nonlinear aspects are presented. The fuzzy control is known to have the ability to deal with nonlinearities without having to use advanced mathematics. The LQR integrated fuzzy control （LQRIFC） simultaneously makes use of the good performance of LQR in the region close to switching curve, and the effectiveness of fuzzy control in region away from switching curve. A new analysis of the fuzzy system behavior presented helps to make possible precise integration of LQR features into fuzzy control. The LQRIFC is verified by simulation to suppress the uncertainty instability more effectively than the LQR besides minimizing the time of the mission proposed.

基于增量非线性动态逆的导弹解耦控制设计

针对导弹大迎角机动存在强耦合动力学特点,提出了一种基于增量非线性动态逆的解耦控制方法,将自动驾驶仪分为高带宽的快变角速率内回路和低带宽的慢变角回路控制,用部分逆近似求解的方法分别设计了增量形式的动态逆控制律对消不同的耦合项,实现控制解耦的目的。典型工况数字仿真结果表明,所设计的导弹增量非线性动态逆控制解耦律大大改善了强耦合动力学下的稳定控制性能。相比传统PID控制,它能够完全消除过载响应的低频振荡和超调量,同时还使得滚转角响应能够准确跟踪指令。

地下矿无人驾驶铲运机系统设计与应用

随着我国矿产资源开发工作向深部发展,复杂的应力条件和恶劣的开采环境严重威胁到井下人员的安全,开采装备无人化是解决井下安全和效率问题的有效手段。结合自动驾驶和远程遥控技术,设计并应用了地下铲运机无人驾驶系统,在千米深井中实现了铲运机出矿作业的全流程无人化。在应用试验中,自动驾驶直线行驶的最大速度达10 km/h以上,转弯最大速度为3 km/h,远程遥控的延迟在10 ms以下。该系统可有效提高矿山生产效益、降低安全事故风险,并有助于推动我国矿山智能化转型升级。

海豚头气动外形导弹主动段过载驾驶仪设计

针对海豚头气动外形导弹主动段飞行过程中存在快速变化的俯仰干扰力矩导致驾驶仪过载指令不跟随的问题,研究了一种基于自适应控制的三回路过载驾驶仪在线调参方法。首先,对纵向短周期下的导弹动力学进行建模,建立三回路过载驾驶仪状态方程,在标称状态下采用极点配置对三回路过载驾驶仪的控制参数进行设计;其次,将标称状态下的驾驶仪视为参考模型,采用模型参考自适应方法,通过设计Lyapunov函数对自适应更新律进行设计。为了增强在建模不确定条件下自适应算法的稳定性,引入投影算子和死区的概念;最后,在气动拉偏条件下对海豚头气动外形导弹的主动段进行三回路自适应过载驾驶仪指令跟踪仿真。仿真结果表明,三回路自适应过载驾驶仪在海豚头气动外形导弹的主动段具有较好的动态跟踪特性。

无人播种平台的设计与分析

为解决传统农业种植过程中人力资源短缺和效率低下的问题,该文针对无人播种平台开展设计与分析,该平台由一个自动驾驶的播种机器人和一个云端控制系统组成,可以通过预先设定的种植方案进行自动化播种。在设计过程中,需要考虑机器人的导航和避障能力、种子的储存和投放方式,以及云端控制系统的实现,可以显著提高种植效率、降低成本和人力资源需求。然而,也需要克服一些问题与挑战,如机器人的可靠性和稳定性、不同农作物的种植要求等。最后系统分析无人播种平台的应用效益。研究结果旨在为现代化农业进程提供新的发展思路与研究方案。

基于Cortex-M3的串口与CAN转换模块的设计与实现

针对采用控制器局域网络(CAN:Controller Area Network)总线的自动操舵系统和采用串口通讯的航海导航设备之间通讯的不匹配问题,设计了一种基于Cortex-M3嵌入式平台的通信转换模块,实现了串口与CAN总线数据的双向转换功能。同时对传统CAN收发器CTM1050存在的信号稳定性不足、波特率精准度低等问题,提出并实现了一种硬件电路的替代方案,提高了数据通讯的时效性和稳定性。基于CAN2.0B扩展帧,设计了自动操舵系统内部CAN总线协议。该协议可根据报文信息优先级分配标识帧,保证了总线数据的有序传输。实验结果表明,该通讯模块功能使用正常且通讯效果良好,具有一定通用性,可在多种需要转换的设备系统上推广使用。

Observer-based Guidance Law Accounting for Second-order Dynamics of Missile Autopilots

Accounting for the missile autopilot as second-order dynamics, an observer-based guidance law is designed based on the dynamic surface control method. Some first-order low-pass filters are introduced into the design process to avoid the occurrence of high-order derivatives of the line of sight angle in the expression of guidance law such that it can be implemented in practical applications. The proposed guidance law is effective in compensating the bad influence of the autopilot lag on guidance accuracy. In the simulations of intercepting non maneuvering targets, targets with step acceleration, and targets with sinusoidal acceleration respectively, the guidance law is compared with the adaptive sliding mode guidance law in the presence of missile autopilot lag. The simulation results show that the proposed guidance law is able to guide a missile to accurately intercept a maneuvering target, even if it escapes in a great and fast maneuver and the autopilot has a relatively large lag.

Adaptive Sliding Mode BTT Autopilot for Cruise Missiles with Variable-Swept Wings

In this paper,an adaptive sliding mode method was proposed for BTT autopilot of cruise missiles with variable-swept wings. To realize the whole state feedback,the roll angle,normal overloads and angular rates were considered as state variables of the autopilot,and a parametric sliding mode controller was designed via feedback linearization. A novel parametric adaptation law was put forward to estimate the nonlinear timevarying parameter perturbations in real time based on Lyapunov stability theory. A sliding mode boundary layer theory was adopted to smooth the discontinuity of control variables and eliminate the control chattering. The simulation was presented for the roll angle and overload commands tracking in different configuration schemes. The results indicated that the controlled system has robust dynamic tracking performance in condition of the large-scale aerodynamic parametric variety resulted from variable-swept wings.

Analysis and improvement of missile three-loop autopilots

The non-minimum phase feature of tail-controlled missile airframes is analyzed. Three selection strategies for desired performance indexes are presented. An acceleration autopilot design methodology based on output feedback and optimization is proposed. Performance and robustness comparisons between the two-loop and classical three-loop topologies are made. Attempts to improve the classical three-loop topology are discussed. Despite the same open-loop structure, the classical three-loop autopilot shows distinct characteristics from a two-loop autopilot with PI compensator. Both the two-loop and three-loop topologies can stabilize a static unstable missile. However, the finite actuator resource is the crucial factor dominating autopilot function.

Missile robust gain scheduling autopilot design using full block multipliers

Reduction of conservatism is one of the key and difficult problems in missile robust gain scheduling autopilot design based on multipliers.This article presents a scheme of adopting linear parameter-varying（LPV） control approach with full block multipliers to design a missile robust gain scheduling autopilot in order to eliminate conservatism.A model matching design structure with a high demand on matching precision is constructed based on the missile linear fractional transformation（LFT） model.By applying full block S-procedure and elimination lemma,a convex feasibility problem with an infinite number of constraints is formulated to satisfy robust quadratic performance specifications.Then a grid method is adopted to transform the infinite-dimensional convex feasibility problem into a solvable finite-dimensional convex feasibility problem,based on which a gain scheduling controller with linear fractional dependence on the flight Mach number and altitude is derived.Static and dynamic simulation results show the effectiveness and feasibility of the proposed scheme.

Design of a robust guidance law via active disturbance rejection control

Focusing on the three-dimensional guidance problem in case of target maneuvers and response delay of the autopilot, the missile guidance law utilizing active disturbance rejection control （ADRC） is proposed. Based on the nonlinear three-dimensional missile target engagement kinematics, the guidance model is es- tablished, The target acceleration is treated as a disturbance and the dynamics of the autopilot is considered by using a first-order model. A nonlinear continuous robust guidance law is designed by using a cascaded structure ADRC controller. In this method the disturbance is estimated by using the extended state observer （ESO） and compensated during each sampling period. Simulation results show that the proposed cascaded loop structure is a viable solution to the guidance law design and has strong robustness with respect to target maneuvers and response delay of the autopilot.

Stabilityanalysis of tactical missile autopilots based on vector margin

A novel stability computation approach for tactical missile autopilots is detailed. The limi- tations of traditional stability margins are exhibited. Then the vector margin is introduced and com- pared with sensitivity function to show their essential relationship. The longitudinal three-loop auto- pilot for tactical missiles is presented and used as the baseline for all the available linear autopilots. Ten linear autopilot topologies using all the measurable feedback components are given with the iden- tical closed-loop characteristic equation and time-domain step response. However, the stability of the ten autopilots differs when considering the actuator dynamics, which limits their application. Then vector margin method is adopted to compute and evaluate the stability of all available autopi- lots. The analysis and computation results show that the vector margin method could better evaluate autopilot stability.

Effect of Autopilot Structure on Proportional Navigation Guidance

The dynamic characteristics of acceleration autopilot and attitude autopilot are discu.ssed in detail. Also, a comparison study was made between these two different types of control schemes for guidance loop. By means of simulation, it is concluded that the guidance accuracy is mainly determined by the slowest subsystem among different system dynamics. For air-to-ground missiles, with limited terminal guidance time, the control scheme of acceleration autopilot combined with proportional navigation guidance （PNG） law is the better choice.

H_∞-Mixed Sensitivity Design of Roll Channel of Bank-to-Turn Autopilot for Small Diameter Bomb

According to requirements of the bank-to-turn (BTT) control for a small diameter bomb (SDB), the robust design problem for the roll autopilot was studied by H∞-mixed sensitivity control method. A roll channel dynamics model was established. Considering the couple between the yaw and roll channel as uncertain disturbance, the roll autopilot was designed using dual-loop scheme which takes a linear quadratic regulator (LQR) as inner-loop, to ensure the control effect of the certain part in model, and an H∞-mixed sensitivity control as outer-loop, to restrain coupling disturbance and strengthen the system's robust performance. The dynamic tracking performance and the robustness for the parameter disturbance of the roll controller were analyzed. The simulated results show that the roll control system functions better and robustly.

Dynamic Model of Flying Machines with the Autopilot

The article considers negative effects of mechanical oscillations of a fuselage on the flying machine autopilot. The dynamic model of control system of flight is made which provides stability and compensates the mechanical oscillations arising in flight of flying machine with the autopilot.

输入饱和约束下导弹自动驾驶仪鲁棒最优自适应控制

针对遭受外部扰动和输入饱和约束条件下的导弹自动驾驶仪系统,研究其鲁棒最优控制问题。首先,引入光滑函数处理输入饱和约束,并设计超螺旋干扰观测器实现对外部扰动的实时估计;然后,结合滑模控制理论,设计基于观测器的自适应滑模控制策略;接着,针对等效滑动模态系统,引入自适应动态规划算法构造评价网络求解哈密顿⁃雅可比⁃贝尔曼(HJB)方程,设计新的更新律在线学习最优控制策略使得系统稳定的同时满足预设的性能指标;最后,导弹自动驾驶仪系统的仿真结果表明了算法的有效性。

基于ROS和Pixhawk飞控自驾仪的无人清扫船研究

本研究旨在探索基于机器人操作系统(Robot Operating System,ROS)和Pixhawk飞控自驾仪的无人清扫船的应用。通过结合先进的自动化技术和海洋保护需求,设计了一种全新的无人船系统,旨在提高海洋环境清洁和生物多样性的保护效率。研究采用了遥感和机器视觉技术,实现了船只自主导航和集中式监测控制。实验结果表明,该无人清扫船系统具有良好的性能和可控性,为实现海洋保护目标提供了新的解决方案。

BTT autopilot design for agile missiles with aerodynamic uncertainty

The approach to the synthesis of autopilot with aerody- namic uncertainty is investigated in order to achieve large maneu- verability of agile missiles. The dynamics of the agile missile with reaction-jet control system （RCS） are presented. Subsequently, the cascade control scheme based on the bank-to-turn （B-I-T） steering technique is described. To address the aerodynamic un- certainties encountered by the control system, the active distur- bance rejection control （ADRC） method is introduced in the autopi- lot design. Furthermore, a compound controller, using extended state observer （ESO） to online estimate system uncertainties and calculate derivative of command signals, is designed based on dynamic surface control （DSC）. Nonlinear simulation results show the feasibility of the proposed approach and validate the robust- ness of the controller with severe unmodeled dynamics.

基于状态输出反馈自适应模糊控制的导弹控制系统设计

针对空空导弹直接力/气动力复合控制问题,提出了一种基于模糊控制和模型参考自适应控制的导弹直接力/气动力复合控制系统。首先建立了直接力/气动力复合控制空空导弹在俯仰通道上的数学模型,分别设计了纯气动舵与直接力/气动力复合的三回路自动驾驶仪。对于直接力/气动力复合驾驶仪直接力难以控制的问题,引入模糊控制对直接力装置的工作时间进行控制并设置了更合适的分配比例,采用状态空间的输出作为反馈,构建模型参考自适应算法优化系统,减小系统的超调量。仿真结果表明,使用该模糊控制和自适应控制设计的控制系统可以使直接力/气动力复合控制导弹更快更准确地跟踪输入指令。

智能车辆局部路径规划与跟踪控制算法研究

针对无人驾驶汽车局部路径规划与跟踪控制,提出一种基于改进A^(*)算法的局部路径动态规划算法及一种基于改进LQR算法控制理论结合模糊控制与PID控制的路径跟踪控制算法。主要包括:搭建无人车辆在Frenet坐标系下利用栅格法构建预行驶区域模型;优化改进节点扩展方向,提出针对无人驾驶的五邻域扩展节点方式;A^(*)算法一次规划出代价值最小的目标节点,二次A^(*)算法规划出实时动态最优路径。另外,搭建以路径曲率变化率和横向误差变化率为状态变量的横向路径模糊跟踪控制模型,搭建以纵向误差和纵向误差变化率为状态变量的模糊PID控制模型解决参数难调问题。通过Carsim、Simulink与Perscan联合仿真平台验证设计的路径规划与跟踪控制算法有效性。