Cable-direct-driven-robot (CDDR) with a 3-link passive serial support

Cable-direct-driven-robots (CDDRs) provided with a passive serial support represent an interesting and rising evolution of planar cable robots. The paper is devoted to present and analyze a novel CDDR robot. The robot consists in a fully actuated CDDR supported against loading normal to the motion plane with a 3-link passive planar serial manipulator. This hybrid structure combines positive features of both parallel and serial architectures, and prevents out-of-plane movements without the necessity for the robot to be supported on the motion plane. The adoption of a 3-link serial manipulator ensures a greater workspace area compared with similar structures that adopt a smaller number of links, and improves specific characteristics of their dynamics. Nevertheless undesired oscillations may occur since the serial manipulator is underconstrained. For this reason damping elements are inserted in the structure. Simulation examples are presented to demonstrate the novel CDDR concept and its dynamics. In addition, a strategy to select proper values of damping coefficients is presented.     

不同重力环境的空间机械臂自抗扰轨迹跟踪控制

针对空间机械臂在地面装调与空间应用时,由于重力环境变化导致机械臂模型发生变化的问题,提出了一种自抗扰控制算法,用于完成空间机械臂轨迹跟踪控制的任务.该算法通过将系统模型及未知外扰作为系统的总和扰动,并利用扩张状态观测器对该扰动进行观测且给予补偿,从而提高了系统抗扰的性能.当机械臂模型随重力环境变化而发生变化时,使用同一个自抗扰控制器对其末端轨迹进行控制,均能取得较好的控制效果.通过对系统的稳定性进行分析,证明了所设计控制器的有效性.将仿真结果与PD控制及自适应鲁棒控制做比较,结果表明该控制算法不仅能适应机械臂模型的变化而且还能有效抵抗系统的扰动,从而使系统具有较强的鲁棒性.     

物联网技术在科研量化管理平台中的应用及探索

科研管理的现代化及高效化是社会发展的趋势,将物联网技术集成到科研管理平台中,能达到高效、科学、高效的效果。完善当前科研管理系统的功能,使得平台除基本的管理功能外,同时具备量化积分功能及论文共享机制等功能,为考核、评价及后续工作提供参考数据,适应当前形势下的复杂需求。     

基于广义预测控制的船舶编队

针对多船舶之间的编队合作问题,对船舶的编队控制进行研究。利用广义预测控制方法在船舶运行中对理想路径曲线进行预测,得出船舶的运动控制策略;通过运用领导-跟随者编队方法,在Cartesian坐标系下建立船舶编队控制模型,基于这种模型建立一系列船舶航迹约束,得到船队跟随者成员的控制策略。同时在船舶运行过程中,加入风浪的扰动,进行模拟仿真,得到船队的运行轨迹。     

Sliding mode disturbance observer-based backstepping control for a transport aircraft

This paper presents a novel control method by integrating the sliding mode disturbance observer- based control and the backstepping control technique, and successfully applies it to a flight control system for heavy cargo airdrop operations. The super-twisting second order sliding mode disturbance observer （SOSMDO） is employed to estimate bounded but otherwise arbitrary disturbances, thus ensuring asymptotic convergence of the estimation error to zero in a finite time. Besides, the integrated controller can significantly improve the robustness of the flight control system to modeling uncertainty and external disturbance in the presence of state/control constraints. The closed-loop stability is guaranteed in the sense of Lyapunov. In addition, the proposed approach can considerably reduce design cycles. The performance of the proposed control method is demonstrated in a very low altitude extraction airdrop simulation with a high-fidelity six-degree-of-freedom transport aircraft model.     

10 kV用无源电子式电压传感器的应用研究

针对传统技术中采用电磁式CT互感器存在的不足,提出了适用于10 kV的无源电子式电压互感器。根据电压互感器的工作原理,介绍了10 kV无源电子式电压互感器在电能表检定装置方面的意义。进一步分析了无源电子式电压互感器在电力设备中应用的重要性和必要性,该技术能够有效地避免传统技术在电力线路信号传输和处理时带来附加误差,大大提高电能计量、保护和测量系统的精度,推进了电力系统朝向数字化、电子化、自动化、网络化的方向发展。实验表明,采用10 kV的无源电子式电压传感器与传统CT互感器相比,误差精度提高了10%以上。     

Observer‐based compensation control of servo systems with backlash

For compensating backlash phenomenon in servo systems, the authors propose an observer method in this paper to estimate both system states and vibration torque before controller design. First, a systematic scheme is given to obtain plant parameters, which is very important in observing system states. This is a parameter estimation principle that gives a crude estimation and computes the differences between the crude and true values. As a result, the precise value of the parameters is obtained by adding together the crude value and the difference. Then, based on the precise estimated parameters, an extended state observer (ESO) is designed to obtain feedback and feedforward signals. Consequently, robust compensation control is achieved by designing an output feedback controller, consisting of a feedback term and a feedforward term. Finally, in order to validate the proposed approach, extensive experiments are performed on a practical servo system with backlash nonlinearity.     

改进麻雀搜索算法求解作业车间调度问题

针对最小化完工时间的作业车间调度问题(JSP),提出改进麻雀搜索算法(ISSA).首先设计有效的编码转换方式,形成JSP离散决策空间与麻雀搜索算法(SSA)连续搜索空间的对应关系.然后,针对SSA在求解后期易陷入局部最优,利用量子计算、正余弦搜索和警戒者数量递减策略对SSA进行改进,同时引入多邻域搜索和高斯扰动策略以弥补SSA在求解离散问题时深度发掘能力不足的弊端.最后,进行FT、LA系列10个测试问题、6种算法和2个应用实例的对比实验.结果表明,ISSA在求解JSP时,能获得更好的最小值、平均值和寻优成功率,验证了ISSA求解JSP的有效性.     

输入饱和与姿态受限的四旋翼无人机反步姿态控制

本文针对四旋翼无人机研究了鲁棒反步姿态控制策略.由于四旋翼无人机结构复杂,其非线性数学模型难以精确建立,因此在控制器设计过程中需要综合考虑模型不确定性、未知外部干扰、输入饱和以及姿态受限等因素.针对模型中的不确定项,使用神经网络进行逼近;对于外部未知干扰,使用非线性干扰观测器进行补偿;使用双曲正切函数逼近饱和函数,解决输入饱和问题;同时使用界限Lyapunov函数设计控制器,确保姿态满足限制条件.最后,设计四旋翼无人机反步姿态控制器,并根据Lyapunov稳定性定理证明了闭环控制系统的有界稳定.仿真结果表明了所研究控制方法的有效性.     

基于QS-ML-PMHT的多目标无源协同定位方法

针对目标个数未知时无源协同定位系统低可观测目标的航迹起始及维持问题,提出一种基于拟蒙特卡罗模拟退火极大似然概率多假设的双基站多目标无源协同定位方法。首先,建立双基站无源协同定位系统数学模型。其次,提出基于极大似然概率多假设的多目标无源协同定位航迹起始算法,通过假设法确定目标个数,并首次利用拟蒙特卡罗模拟退火算法解决极大似然概率多假设中多目标的优化求解问题,以提高多目标检测跟踪性能。最后,通过滑窗法实现航迹维持。仿真结果表明,所提方法能够有效解决目标个数未知时双基站无源协同定位系统低可观测目标的航迹起始及维持问题。