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1、本科毕业设计(本科毕业论文)外文文献及译文文献、资料题目:Vibration suppression of fixed-time jib crane maneuvers文献、资料来源:网络文献、资料发表(出版)日期:2010.11院 (部): 机电工程学院专 业: 机械工程及自动化班 级: 机械0808姓 名: 秦梅学 号: 指导教师: 周海涛翻译日期: 2012.3.26外文文献:Vibration suppression of fixed-time jib crane maneuversABSTRACTA jib crane consists of a pendulum-like end
2、line attached to a rotatable jib. Within this general category of cranes there exist devices with multiple degrees of freedom including variable load-line length and variable jib length. These cranes are commonly used for construction and transportation applications. Point-to-point payload maneuvers
3、 using jib cranes are performed so as not to excite the spherical pendulum modes of their cable and payload assemblies. Typically, these pendulum modes, although time-varying, exhibit low frequencies. The resulting maneuvers are therefore performed slowly, contributing to high construction and trans
4、portation costs. The crane considered here consists of a spherical pendulum attached to a rigid jib.The other end of the jib is attached to a direct drive motor for generating rotational motion. A general approach is presented for determining the open-loop trajectories for the jib rotation for accom
5、plishing fixed-time, point-to-point, residual oscillation free,symmetric maneuvers. These residual oscillation free trajectories purposely excite the pendulum modes in such a way that at the end of the maneuver the oscillatory degrees of freedom are quiescent. Simulation results are presented with e
6、xperimental verification.Keywords: Rotary Crane, Control, Swing-Free, Oscillation-Free, Input Shaping 1 INTRODUCTION.Construction and transportation cranes can generally be grouped into one of two categories based on their configuration. The first category consists of overhead, gantry cranes. These
7、systems incorporate a trolley which translates in the horizontal plane. Attached to the trolley is a load-line for payload attachment. Typically, they have varying load-line length capabilities. Thesecond category consists of rotary cranes. As the name implies, the load-line attachment point undergo
8、es rotation. Other degrees of freedom may exist such as translation of the load-line attachment point along the jib, variable load-line length, or if the jib is replaced by a boom, the characteristic boom rotational motion, known as luffing* Auernig and Troger consider time optimal payload maneuvers
9、 of a gantry crane undergoing trolley translation and load-line length change. The coupled, nonlinear equations of motion and adjoint equations, obtained from the application of Pontryagins maximum principle, are solved analytically for the cases of constant and variable hoisting speeds. In both cas
10、es the maneuvers are developed such that the payload is residual oscillation free. Moustafa and Ebeid demonstrate a state feedback controller for damping load sway for a gantry crane configured to move along two orthogonal directions in the horizontal plane. This work is expanded on by Ebeid et. al.
11、 to incorporate actuator dynamics into the crane model. Fliess et. al. investigate a feedback linearizing controller for a one-dimensional gantry crane. Trolley traversal and load-line length changes are considered. Simulation results indicate the ability of the closed-loop controller to control loa
12、d sway for relatively slow maneuvers. This same system is examined by Nguyen where simulation and experimental results of a nonlinear st2te-feedback controller is used. Small motions are assumed about a specified operating point. This allows for decoupled equations of motion and decoupled controller
13、 design.Sakawa and Nakazumi investigate a rotary crane undergoing hub and boom rotation and load hoisting using a combined open and closed-loop approach. The open-loop input to the crane is designed based on a postulated set of functions such that the sway motion of the load is excited minimally. Th
14、e closed-loop controller is then switched on when the maneuver is near the end, providing significant sway damping. Vaha et. al. generate suboptimal, minimum time inputs for a rotary crane. Tracking is achieved via a state feedback control law. However, radial sway, due to centripetal acceleration o
15、f the payload, is not compensated. Souissi and Koivo consider a rotary crane undergoing a boom-rotation-boom maneuver using a proportional-integral-derivative controller similar to Fliess et。al. 4. The simulation model considers both radial and tangential payload sway, however, the control strategy
16、used results in residual load oscillation.In this paper a procedure for generating open-loop inputs for a rotary jib crane is introduced. The primary maneuver of interest is the residual oscillation, point-to-point movement of a payload. The input angular acceleration to the jib motor is postulated
17、as having a pulse-coast-pulse form. A numerical optimization technique is used to generate the parameters which define this pulse sequence such that the maneuver is residual oscillation free . Of secondary interest are maneuvers where the payload oscillates in a specified manner at the end of the ma
18、neuver. Again, the pulse sequences are designed via numerical optimization. Experimental results for these maneuvers verify the results of the numerical optimization procedure.2. CRANE DESCRIPTIONThe crane considered here consists of a rotatable jib with a load-line attached to the end. A mass, repr
19、esenting a payload, is attached to the end of the load-line. This apparatus is shown in Fig. 1 The coordinate system is attached to the jib and rotates about the hub with angular rate y .The rotation angles el.,8 are defined as rotations of the load-line about the 8, 6, axes respectively. The attach
20、ment point of the load-line to the jib is at a distance x from the center of rotation of the hub. The load-line has length L and the payload has mass m .The two rotations will from now on be referred to as the radial (0,) and the tangential (e1 ). The input to this system is the hub rotation traject
21、ory y ( t ) and the outputs are the rotation angles of the load-line, 0, ( t ),e, ( t ) . The experimental system uses a constant velocity, computer controlled, direct-drive, motor. Physical values for x, m, L are given in Table 1. . As mentioned in the introduction, several maneuvers are examined a
22、ll of which consist of a 90 jib rotation. The first is designed such that the payload is residual oscillation free .The second allows only tangential oscillation at the end of maneuver, while the third allows only radial oscillation of the payload.3. RESULTSTable 2 shows the parameters obtained via
23、the optimization process which result in the three maneuvers of interest. Plots of jib rotation are shown in Fig. 3 through Fig. 5. The angular accelerationprofiles implemented on the hardware, described in Section2, produce the desired maneuvers with no modification of the inputs. This implies an e
24、xcellent ability to model and simulate this system. The absence of residual oscillation was determined by observation during testing. Due to the agreement between simulation and experiment, simulation plots are presented.The residual oscillation free maneuver of Fig. 3 uses an acceleration profile s
25、ymmetric in time about the half period of the maneuver. This is consistent with the results obtained by Petterson and Robinett lo. Allowing pendulum sway in either the radial or tangential directions only, requires nonsymmetric acceleration histories as in Fig. 4 and Fig. 5. Plots of the pendulum sw
26、ay are shown in Fig. 6 through Fig. 8. Centrifugal effects during the maneuver are illustrated by Fig. 9 through Fig. 11which show the projection of the payload and the jib end onto the horizontal surface. In all cases the load is observed moving initially outward from the tip path.The acceleration
27、profiles developed here purposely excite the oscillatory motion of the load. This is illustrated by investigating the Fourier series of the acceleration history. Examination of the quasi-static stiffness matrix of Eq. 6 throughout the residual oscillation-free maneuver indicates only slight changes
28、in the quasi-static natural frequencies of the load. Specifically, the nominal (nonrotating)natural frequency in both radial and tangential directions is 0.995 Hz .The initial acceleration pulse, with zero velocity, results in a slight increase of this frequency. However, the softening effect of the
29、 angular velocity during the maneuver causes the quasi-static natural frequency to decrease to 0.978 Hz at the half-period of the maneuver. This change in quasi-static natural frequency is symmetric in time about the half-period. Fig. 12 shows a 20-term Fourier sine series expansion of the input acc
30、eleration history. The first 5 coefficients of the jib angle history, obtained from integrating the acceleration history, are given in Table 3.Finally, some mention of the robustness of this technique is in order. It is expected that the performance of the system will suffer due to inaccuracies of t
31、he model. Sensitivity analyses indicate that the most important model parameter is the load-line length. Small errors in this quantity can lead to residual vibration, whereas similar errors in jib length can be tolerated without significant degradation of performance. Sensitivity of the response due
32、 to the discontinuous nature of the acceleration profile can be reduced by using a smoothed profile such as a versine function. This technique has been used for vibration suppression of a flexible rod, and is applicable here. l24. SUMMARYA method for generating residual oscillation free maneuvers fo
33、r a rotary jib crane has been presented. This method uses the model of the system in conjunction with a numerical optimization process to generate parameters describing the jib angular acceleration profile. Maneuvers obtained using this procedure were experimentally verified demonstrating not only t
34、he usefulness of this method but also the ability to accurately simulate such a system. The input profiles were also shown to purposely excite the quasi-static frequencies of the payload in order to decrease the operating time of the jib crane (i.e., decrease construction costs).5. ACKKNOWLEDGMENTST
35、his work performed at Sandia National Laboratories is supported by the U S Department of Energy under contract DE-ACO4-94AL.85000.6. REFERENCES1. J.W. Auernig and H. Troger, “Time Optimal Control of Overhead Cranes with Hoisting of the Load,” Automatica, Vol. 23,No. 4 pp. 437-447, 1987. ,2. K.A.F. M
36、oustafa and A.M. Ebeid, “Nonlinear Modeling and Control of Overhead Crane Load Sway,” Journal of Dynamic Systems, Measurement, and Control, Vol. 110,pp. 266-271,1988.3. A.M. Ebeid, K.A.F. Moustafa and H.E. Emara-Shabaik, “Electromechanical Modelling of Overhead Cranes,” International J o u m l of Sy
37、stems Science, Vol. 23,No. 12,pp.2155-2169,1992.4. M. Fliess, J. Levine P. Rouchon, “A SimplifiedApproach of Crane Control via a Generalized State-Space Model,” IEEE Proceedings of the 30th Coilferenceon Decision and Control, Brighton, England, pp. 736-741, 1991.5. H.T. Nguyen, “State-Variable Feedb
38、ack Controller for an Overhead Crane,” Journal of Electrical and Electronics Engineering,Australia, Vol. 14 ,No. 2, pp. 75-84,1994.6. Y. Sakawa and A. Nakazumi, “Modeling and Control of a Rotary Crane,” Joumal Of Dynamic Systems, Measurement, and Control, Vol. 107,pp. 200-206, 9 518. .中文译文:振动抑制的固定式悬
39、臂起重机演示摘要:一个旋臂起重机由一个钟摆般的结束线连接到一个可旋转的吊臂。在此起重机的一般类别中存在具有多自由度,包括变量的负载线的长度和可变臂长的设备。这些起重机通常用于建筑和运输等领域。点至点的有效载荷机动臂起重机进行,以免激发他们的电缆和有效载荷组件的球形钟摆模式。通常情况下,这些钟摆模式,尽管时间变,表现出低频率。因此产生的回旋是缓慢进行的,为高的建筑和运输成本做出贡献。起重臂这里由刚性臂连接到一个球形摆。臂的另一端连接到一个直接驱动电机产生旋转运动。一个普遍的做法是确定完成固定时间,点至点,无残留振荡臂旋转的开环的轨迹对称回旋。这些残留振荡的自由轨迹有意激发在这样一种方式,在演习结
40、束时,自由振荡是静态的钟摆模式。模拟结果与实验验证。关键字:旋转式起重机,控制,水平自由度,无振动,输入整形1、 引言建设和交通起重机根据其配置,一般可分为两类。第一类包括开销式龙门起重机。这些系统包括一个在水平面的小车。无轨电车是连接到负载线的有效载荷附件。通常情况下,他们有不同的负载线长度。第二类包括旋转式起重机。顾名思义,负载线的连接点可进行旋转。其他的自由程度可能存在,如连接的负载线的连接点沿臂,变负载线的长度,或如果替换,具有旋转运动特征的臂,众所周知,作为变幅臂架。auernig和Troger考虑龙门起重机进行小车运动和负载线的长度变化的最佳负载回旋。耦合,运动和伴随方程的非线性方
41、程组,获得庞特里亚金的最大值原理的应用,解决了常量和变量的吊装速度的情况分析。在这两种情况下,回旋是发展的有效载荷如残留振荡。穆斯塔法和奥贝德展示了一门式起重机的阻尼载荷配置在水平面沿着两个正交方向摇摆的状态反馈控制器。这项工作是扩大对奥贝德等起重机模型纳入执行机构动力学。佛里斯等为一维的龙门吊调查反馈线性化控制器。拉杆穿透和负载线的长度变化。仿真结果表明,闭环控制器的控制能力对于回旋负荷摆动相对缓慢。此相同的系统研究由阮云道一个的非线性st2te反馈控制器的仿真和实验结果承担有关指定的经营点小运动这使得运动方程解耦和解耦控制器的设计。Sakawa和Nakazumi调查旋转起重机进行枢纽、臂的
42、旋转和载荷悬挂,使用相结合的开放式和闭环方法起重机开环输入的功能,如负载的摆动运动被激发最低推测的基础上设计闭环控制器,然后接通演习接近尾声时,提供明显的摆动阻尼。vaha等产生最理想的旋转起重机,最短的时间投入通过状态反馈控制律通过跟踪的然而,由于向心力的有效载荷,径向摇摆,没有得到补偿。 souissi和Koivo考虑使用比例 - 积分 - 微分控制器类似的佛里斯等人经历了旋转臂操纵旋转起重机 的仿真模型,同时考虑径向和切向载荷摆动,然而,在剩余的载荷振荡控制策略的使用结果。本文介绍产生一个旋转的旋臂起重机开环输入程序感兴趣的主要策略是残留振荡,点至点的有效载荷的运动假设有一个脉冲,脉冲形
43、式输入角加速度臂电机数值优化技术用于生成定义演习如残留振荡脉冲序列的参数二次感兴趣的是回旋在演习结束时的有效载荷,在指定的方式振荡再次,脉冲序列通过数值优化设计这些回旋的实验结果验证了数值优化过程的结果。2、 吊车描述这里考虑的起重机由一个旋转臂与负载线连接到终端群众,代表的有效载荷,连接到负载线此设备如图 1坐标系统是连接臂和旋转角速率为y的枢纽旋转角度,8 EL。负载线的旋转约8,6,轴分别定义。臂负载线的连接点,如在一个旋转的枢纽中心的距离为x负载线的长度L和有效载荷质量为m,从现在起将交由两个旋转的径向(0)和切向(E1)这个系统的输入如枢纽旋转轨迹Y(T)和输出负载线,0,(T),E
44、(t)的旋转角度。实验系统采用恒定的速度,电脑控制,直接驱动,电机表1给出了物理,X,M,L值。在介绍中提到,回旋是检查,其中包括90“臂旋转,首先是设计,有效载荷如残留振荡第二只允许在操纵结束的切向振动,而第三个允许只有径向振荡的有效载荷。5。结果表2显示了三个回旋利用率通过优化过程中获得的参数臂旋转的曲线图所示通过图3 5。在硬件上实现的角加速度型材,在第2节所述,生产没有修改输入所需的回旋这意味着一个优秀的建模和模拟这个系统的能力在测试过程中的残留振荡的情况下通过观察确定由于仿真和实验之间的协议,仿真图。图残留振荡的自由操纵 使用时间约半期的操纵加速度分布对称;这是与Petterson和
45、罗比内特劳的方法得到的结果一致允许在径向或切向方向的钟摆摆动,只需要在图非对称加速记录 4和图 5。钟摆摆动的曲线图所示 6,通过图 8。演习过程中的离心效应由图所示 9,通过图 11which显示投影的有效载荷和臂架底的水平表面上。在所有情况下的负载观察尖路径从最初向外移动这里的加速发展概况刻意激发振荡运动负荷。调查傅里叶级数的加速记录说明了这一点。准静态刚度矩阵式的检查。整个剩余的自由振荡回旋表明,在准静态负载的自然频率只有轻微的变化。具体来说,标称(非旋转)在径向和切向方向的固有频率如0.995赫兹。初始加速度脉冲,速度为零,在这个频率略有增加的结果。然而,在演习角速度软化效应导致的准静
46、态的自然频率,在演习期间半减少到0.978赫兹。这在准静态的自然频率的变化是在大约半周期的时间对称。图12显示的输入加速度记录20长期Fourier正弦级数展开。表3给出了臂的角度整合加速记录从获得的记录,前5个系数。最后,有些值得一提的是这项技术的可靠性。预计该系统的性能将受到不准确的模型影响。敏感性分析表明,最重要的模型参数是负载线的长度。这些质量上的小错误可能导致残余振动,性能显着降低,而臂长的类似的错误,也不可容忍。由于加速剖面的连续性质的响应灵敏度,可以减少使用平滑的轮廓,如正矢函数。这项技术已用于灵活的杆振动抑制,并在这里适用。6. 总结旋臂起重机旋转产生的残留振荡而自由回旋的方法
47、已被提出。此方法使用的系统模型上的结合数值优化过程描述臂角加速度剖面上的生成参数。演习使用此过程中获得的实验验证表明不仅这种方法的实用性,但也能够准确地模拟系统。输入配置上的也显示,以刻意激发准静态载荷上的频率,以减少臂起重机(即降低建筑成本)上的工作时间。7致谢桑迪亚国家实验室进行上的这项工作如由美国能源部支持根据合同DE - ACO4-94AL.85000上的。8.参考文献1. J.W. auernig H. Troger,“时间最优控制的桥式吊车吊装的负载,”自动化卷。 23号4页437-447,1987。 2. K.A.F.穆斯塔法和上午奥贝德,“非线性建模与控制的桥式起重机载荷摆动,”动态系统,测量控制卷。 110页266-271,1988。3.上午奥贝德,K.A.F.穆斯塔法阁下埃马拉Shabaik,“桥式起重机上的机电模拟,”国际系统科学,卷J ouml。 23号12,pp.2155-2169,1992。4.M.佛里斯,J. P. Rouchon,“通过广义状态空间模型起重机控制SimplifiedApproach上的莱文,”30 Coilf
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