沈阳自动化所旋翼飞行机器人完成全功能自主飞行试验

由中科院沈阳自动化所机器人学国家重点实验室旋翼无人机组自主研发的15公斤负载级旋翼飞行机器人,日前在无锡某空域完成了全自主起飞、悬停、爬升、加减速、航迹跟踪、下降等飞行科目后,稳稳地降落在了预定位置,成功完成了全功能自主飞行。此次试飞标志着旋翼飞行机器人完成使命任务过程中已经实现不需要任何人为参与,为多项国家级项目的完成奠定了重要的基础。旋翼飞行机器人以其在多领域的潜在用途而受到国内外的普遍重视。但受其涉及多学科、系统复杂、技术封闭等影响,目前仅有美国、奥地利、瑞士等少数国家具备旋翼飞行机器人全功能自主飞行技术。此次试飞成功标志着沈阳自动化所在旋翼飞行机器人研究方面取得了重大突破。     

输入约束下多旋翼飞行机器人的大范围镇定控制

多旋翼飞行机器人具有良好的飞行稳定性,受到了越来越多的关注.而在某些特殊应用中,如:从较大飞行器上实施空投、瞬态失稳恢复等,往往需要多旋翼飞行机器人从一个高度不稳定的非零初始状态安全、快速地切换到稳定飞行模态,这就是所谓的大范围镇定控制问题.解决该问题面临的主要困难是如何在调节过程中避免飞行机器人进入到输入饱和区,从而引起周期旋转运动,导致系统完全失控.本文针对该问题,以四旋翼飞行机器人为例,详细分析了控制输入约束形式,并对6自由度模型进行了适当简化,构建了二维平面下考虑控制输入约束的非线性动力学模型;在此基础上,基于控制Lyapunov函数概念,提出了一种改进的广义逐点最小范数控制策略,构建了输入约束下的四旋翼飞行机器人大范围镇定控制器.该方法具有明确的解析控制结构,所设计的控制器满足四旋翼飞行机器人的全部控制输入约束.仿真结果表明,对比常规的线性化控制策略,该方法能在考虑控制约束的前提下避免控制器失效,实现四旋翼飞行机器人的大范围渐进稳定.     

旋翼飞行机器人研究进展

旋翼飞行机器人是面向空中自主作业需求,将旋翼飞行器与多自由度机械臂相结合所提出的新型机器人.该机器人作业过程中旋翼飞行器、机械臂与作业目标之间的动态相对运动以及与作业目标接触过程中未建模外力、力矩扰动使自主控制受到极大挑战.本文将针对旋翼飞行机器人的结构演变及关键技术、作业机构集成技术进行综述.从动力学建模及动力学特性分析、动态运动约束/力约束下的协调规划、非结构环境下的运动和作业控制、面向任务动态操作的环境感知、面向任务的实验系统构建与实验验证五个方面初步构建了旋翼飞行机器人自主作业理论体系.     

四旋翼无人机时延模糊自抗扰容错控制

针对四旋翼无人机系统执行器故障问题，为改善飞行控制系统性能，提出一种时延模糊自抗扰容错控制。首先，根据四旋翼无人机系统非线性数学模型和执行器故障模型，选择模糊自抗扰控制器作为基准控制器，在未发生执行器故障的情况下，使飞行控制系统保持稳定；其次，在发生执行器故障的情况下，利用时延控制技术估计故障信息，并与模糊自抗扰控制相结合，实现容错控制；最后，对所研究的容错控制算法进行数值仿真分析，仿真结果表明：把时延控制与模糊自抗扰控制相结合，能有效调节执行器故障，使飞行控制系统对故障产生的干扰具有良好的鲁棒性。     

旋翼飞行机器人完成全功能自主飞行试验

由中科院沈阳自动化所机器人学国家重点实验室旋翼无人机组自主研发的15kg负载级旋翼飞行机器人已在无锡完成了全功能自主飞行实验,在完成了全自主起飞、悬停、爬升、加减速、航迹跟踪、下降等飞行科目后,机器人稳稳地降落在了预定位置。此次试飞标志着旋翼飞行机器人完成使命任务过程中已经实现不需要任何人为参与,为多项国家级项目的完成奠定了重要的基础。     

水下机器人推力器容错控制技术的研究

为保证自主式水下机器人在高压、可见度差的未知海洋环境下顺利完成作业任务， 必然要求水下机器人具有容错控制能力．本文主要以哈尔滨工程大学研制的“智水Ⅲ” 型水下机器人为对象，探讨水下机器人推力器容错控制技术．文中先给出在正常情况下水下 机器人的解耦控制器及推力分配，然后给出了在推力器出现故障时的容错控制策略．仿真结 果表明，该控制器及容错控制策略都能达到很好的控制精度．     

微型五维指尖力/力矩传感器的研究

本文介绍了RPJ D型喷浆机器人的机械机构，重点给出了其分布式计算机控 制系统的设计过程．将容错技术、故障诊断技术和抗恶劣环境技术引入喷浆机器人控制系统 中，采用不同的冗余配置方式实现了控制系统规划级和控制级计算机系统高可靠性设计．现 场应用表明，完全满足了喷浆机器人在恶劣环境下工作的要求．     

RPJ-D型喷浆机器人机械结构及其分布式计算机控制系统的可靠性设计

本文介绍了RPJ-D型喷浆机器人的机械机构，重点给出了其分布式计算机控 制系统的设计过程．将容错技术、故障诊断技术和抗恶劣环境技术引入喷浆机器人控制系统 中，采用不同的冗余配置方式实现了控制系统规划级和控制级计算机系统高可靠性设计．现 场应用表明，完全满足了喷浆机器人在恶劣环境下工作的要求．     

一种容错飞行控制的神经网络方法研究

文章提出了一种新的主动容错飞行控制系统设计方法,可同时进行飞控系统执行器的故障诊断和容错控制;首先建立飞机执行器故障模型,接着应用改进的BP神经网络算法,进行飞行控制系统模型辨识,实时进行故障诊断;然后根据故障诊断信息进行自适应容错控制,为了克服故障系统引起的模型误差和非线性因素的影响,设计了自适应神经网络PID参数整定和动态逆控制器,对飞行控制系统执行器故障进行容错控制,以实现系统的良好模型跟踪和动态性能;仿真结果表明,在保证闭环系统稳定的前提下,实现了执行器的在线故障诊断与容错控制,达到了理想的效果.     

非线性系统故障诊断与容错控制技术

在分析非线性系统故障诊断与容错控制技术特点的基础上,研究了该技术在国内外的研究进展和主要方法.同时,比较了几种常见故障诊断和容错控制方法的特点.最后总结了非线性系统故障诊断与容错控制领域亟待解决的几个重点和难点问题,并对该研究领域的发展趋势进行了展望.     

未知环境中移动机器人故障诊断与容错控制技术综述

以我国月球探测为研究背景，以轮式移动机器人为研究对象，介绍了在外星球表面等未知环境中进行深空探测的移动机器人的故障模型和传感器误差模型，分析了未知环境中移动机器人故障诊断与容错控制的特点.在此基础上综述了国内外在该领域的研究进展和主要方法，包括基于多模型的方法、基于粒子滤波器的方法、基于传感器信息融合的方法以及层次容错结构等. 最后,总结了该领域待解决的几个难点问题,并对该研究领域的发展趋势进行了展望.     

Bibliographical review on reconfigurable fault-tolerant control systems

In this paper, a bibliographical review on reconfigurable (active) fault-tolerant control systems (FTCS) is presented. The existing approaches to fault detection and diagnosis (FDD) and fault-tolerant control (FTC) in a general framework of active fault-tolerant control systems (AFTCS) are considered and classified according to different criteria such as design methodologies and applications. A comparison of different approaches is briefly carried out. Focuses in the field on the current research are also addressed with emphasis on the practical application of the techniques. In total, 376 references in the open literature, dating back to 1971, are compiled to provide an overall picture of historical, current, and future developments in this area.     

An adaptive technique for robust diagnosis of faults with independent effects on system outputs

In this paper, Fault Detection and diagnosis (FDD) of faults with independent effect on system outputs by using the adaptive observer technique are investigated. At first, a class of linear systems without model uncertainty is considered. Then, a general situation where the system is subjected to either model errors or external disturbance is discussed. Robust adaptive control techniques are applied to guarantee convergence of certain signals to residual sets. An extension to FDD for a class of non-linear systems with non-linear fault function is extensively investigated. The novelty of this paper is that the strict positive realness (SPR) requirement on the plant transfer function in existing results is removed at the expense of requiring the existence of a positive definite solution to a certain matrix inequality. Furthermore, the problems of stabilization and robust stabilization by fault-tolerant control (FTC) and robust FTC are studied respectively, and faulttolerant controllers are designed to stabilize the close-loop systems. An aircraft example and a numerical example are included to verify the applicability of the proposed diagnosis methods.     

基于定量模型的故障诊断及其性能指标研究

介绍了故障诊断的基本概念,提出了基于定量模型FDD技术的5种故障分类模式,分析了基于定量模型FDD技术的基本原理,对提出的基于定量模型FDD技术的性能指标进行了研究和讨论。     

Robust and Active Fault-tolerant Control for a Class of Nonlinear Uncertain Systems

A novel integrated design strategy for robust fault diagnosis and fault-tolerant control (FTC) of a class of nonlinear uncertain systems is proposed. The uncertainties considered in this paper are more general than those in other existing works, and faults are described in a new formulation. It is proven that the states of a closed-loop system converge asymptotically to zero even if there are uncertainties and faults in a system. Simulation results on a simple pendulum are presented for illustration.     

Adaptive fault diagnosis and fault-tolerant control of MIMO nonlinear uncertain systems

This article presents an integrated fault diagnosis and fault-tolerant control (FTC) methodology for a class of nonlinear multi-input–multi-output systems. Based on the fault information obtained during the diagnostic procedure, an FTC component is designed to compensate for the effect of faults. In the presence of a fault, a baseline controller guarantees the boundedness of all the system signals until the fault is detected. After fault detection and then again after isolation, the controller is reconfigured to improve the tracking performance using online fault diagnostic information. Under certain assumptions, the stability and tracking performances of the closed-loop system are rigorously investigated. It is shown that the system signals always remain bounded and the output tracking error converges to a neighbourhood of the origin of the state space.     

Application of agent technology concepts to the design of a fault-tolerant control system

This work concerns the applicability of agent technology concepts to the design of a plant fault-tolerant control system. The operation of the fault-tolerant system is enhanced by decomposing it into autonomous subsystems and by turning them into agents. The detailed development of one of the agents, the feed line of the process, is presented and its performance is tested by simulation. The proposed framework meets the control objectives and features a significant level of fault tolerance to sensor and actuator failures. This is achieved using an observer based fault detection and diagnosis (FDD) unit. Moreover, this work shows how the control strategy may be altered to tackle a case of severely impacted control capability.     

A survey of fault-tolerant controllers based on safety-related issues

Fault-tolerant controllers (FTCs) have recently gained considerable attention due to their important role in maintaining the safety of modern technological systems via configured redundancy. The basis of a FTC through an analysis of the requirements of safety-critical systems is introduced in this paper. The development of passive FTC approaches, including their advantages and disadvantages, is discussed based on safety requirements. Closely associated with the safety-relevant issues, recent progress in active FTC design methodologies is reviewed in the sequence of fault detection and diagnosis (FDD), reconfigurable controls, and integration of FDD and reconfiguration. In summary, it is the view of this paper that addressing safety issues is the key to further development of FTCs.     

Correlation-based fault-tolerant controller design for MIMO systems under the Youla parameterisation

This paper develops a correlation-based method into the Youla parameterisation structure for a fault-tolerant controller design strategy. By tuning the Youla parameters with the proposed correlation-based algorithm, a number of conditional faults described by the dual Youla parameters are attenuated. The traditional fault-tolerant control (FTC) schemes under the Youla parameterisation often require the gradient information of the defined cost function for minimisation, which is either tedious or even unfeasible with unknown fault model. However, the proposed correlation-based FTC algorithm in this paper can compensate the faults via system data without the explicit fault model or the cost function gradient information. It is also proved that the algorithm convergence can be achieved without identifying the unknown fault model. For illustration, a simulation example with corresponding comparisons are presented to show the effectiveness of the proposed method in the end.     

Fault estimation and fault tolerant control for linear stochastic uncertain systems

This article investigates the fault estimation and fault tolerant control (FTC) problems for linear stochastic uncertain systems. By introducing the fictitious noise, the fault is augmented as part of the systems state, and then a robust estimator is proposed to simultaneously obtain the state and fault estimation. Based on the estimated information, the active FTC is presented to eliminate the impact of the fault. Finally, a simulation example is conducted to demonstrate the effectiveness of our main method.