二级倒立摆摆起控制的研究

通过对二级倒立摆系统的理论分析，研究二级摆从自然悬垂位置摆到倒立点位置的摆起控制问题，提出了基于动态设计变量优化算法的复杂非线性系统控制策略．仿真实验证明，该策略可成功地实现圆轨和直轨两种二级倒立摆的摆起控制，并且算法具有较快的收敛速度和较高的计算精度．     

基于H∞环路成形和自适应神经模糊推理系统的模糊控制器设计

H_∞环路成形方法设计的控制器阶次较高,不便于工程实现和参数调整;用传统方法确定模糊控制器隶属度函数的参数和模糊规则比较费时且难以保证鲁棒性能和时频域性能指标.针对上述情况,提出了一种综合运用H_∞环路成形和自适应神经模糊推理系统来设计模糊控制器的方法.首先采用H_∞环路成形设计方法,得到鲁棒裕量、动态和稳态性能都符合要求的控制器,然后用自适应神经模糊推理系统来逼近此控制器,最后根据自适应神经模糊推理系统参数确定相应的模糊控制器规则和参数.该方法确定模糊控制器隶属度函数的参数精确而省时,且能保证控制器具有较强的鲁棒性和良好的控制效果.通过对小车倒立摆系统进行的仿真,验证了该控制器设计方法的有效性.     

Human-like natural behavior generation based on involuntary motions for humanoid robots

Human behaviors consist of both voluntary and involuntary motions. Almost all behaviors of task-oriented robots, however, consist solely of voluntary motions. Involuntary motions are important for generating natural motions like those of humans. Thus, we propose a natural behavior generation method for humanoid robots that is a hybrid generation between voluntary and involuntary motions. The key idea of our method is to control robots with a hybrid controller that combines the functions of a communication behavior controller and body balancing controllers. We also develop a wheeled inverted pendulum type of humanoid robot, named “Robovie-III”, in order to generate involuntary motions like oscillation. By applying our method to this robot and conducting preliminary experiments, we verify its validity. Experimental results show that the robot generates both voluntary and involuntary motions.     

多级旋转式倒立摆的建模与分析

运用刚体的动力学知识对多级旋转式倒立摆系统进行了动力学分析,归纳其规律性,并推导出旋臂及各级摆杆的运动微分方程,从而获得任意级旋转式倒立摆的非线性数学模型。文中还对旋转式倒立摆系统进行了能控性分析。最后利用MATLAB对一级、二级旋转式倒立摆的控制进行了仿真,并得到较好的仿真结果。     

VS‐CONTROL WITH TIME‐VARYING SLIDING SECTOR — DESIGN AND APPLICATION TO PENDULUM —

In general, a Variable Structure (VS) system is designed with a sliding mode. Recently a sliding sector, designed by an algebraic Riccati equation, has been proposed to replace the sliding mode for chattering‐free VS controllers. In this paper we extend the design algorithm for the sliding sector to a time‐varying sliding sector. The time‐varying sliding sector is defined by functions dependent on both state and time, hence time‐varying uncertainty can be considered. The VS controller is designed to stabilize an uncertain system, quadratically. The design procedure for real systems is introduced via an implementation to the control of “Furuta pendulum”. To enhance the stability it is necessary to compensate the time‐varying nonlinear static friction of the actuator adequately, hence this problem is a good example to demonstrate the performance of the proposed VS control method. In the experiment, it will be shown that the VS control with the time‐varying sliding sector is superior to an orthodox chattering‐free VS control.     

Optimum design of mounting components of a mass property measurement system

Measurement of inertia properties of aerospace vehicle and submarine are vital to meet the intended motion objectives. The Moment of Inertia (MOI) is calculated by measuring the frequency of free torsional oscillation of the object mounted on a nearly friction less air bearing. For getting accurate measurement and to nullify the effect of undesired vibrations, the stiffness of the different components of the mounting and fixture (torsion rod, flexure) should be maintained appropriately. The optimum design of torsion rod and flexure is based on ensuring desired natural frequencies in different modes. Initiating with an analytical approach, the actual dimensions of the components are determined based on natural frequencies obtained by finite element analysis of the components. Simulated results are verified with experimental results.     

块系覆岩中摆型波传播对巷道支护动力响应影响

为研究支护体自身的动力响应规律,通过理论和计算分析岩体中的非线性摆型波传播对巷道支护动力响应的影响,根据摆型波在非连续自应力块系上覆岩体中传播时的支护动力响应模型,研究上覆岩块间的黏弹性性质及岩块破坏对支护动力响应的影响。通过计算分析得出,上覆岩块间弹性下降时,支护的动态受拉和受压幅值随之下降且周期变大;上覆岩块间阻尼增大时,支护的受拉和受压周期不变,但周期内的微扰动逐渐消失且幅值略有下降;上覆岩块沿垂直冲击方向破裂成两个子块时,支护的受拉和受压次数增加。     

设置FPS质量调谐阻尼器减振效果分析研究

根据拉格朗日方程推导了结构设置FPS调谐质量系统地震动力反应分析计算公式,并考虑了接触面滞滑效应的影响。分析与计算结果表明:设置质量调谐系统之后,结构动力反应层间位移有所减小。当接触面滑动摩擦系数为0.15左右、滑道半径为0.7 m、调谐附加质量为楼层质量的1.4倍以上时,质量调谐系统具有较好的减振效果、消能效果与复位能力。     

Stochastic rotational response of a parametric pendulum coupled with an SDOF system

In this paper, parametric excitation of a lumped mass pendulum is investigated when having its pivot point vertically excited. Such a system is described by a sinus type nonlinear Mathieu equation and attention is drawn to the rotational motion of the mass. A single-degree-of-freedom (SDOF) system is used as a base for the pendulum, floating on ocean waves and being externally excited by them thus falling into the subclass of autoparametric systems. Due to the random nature of waves, a narrow-band stochastic process is used to model the environmental excitation. The effect of dry friction is considered and the interaction between the pendulum's rotational response and the base is studied.