【作者】 张婷婷；

【导师】 王欣；

【作者基本信息】 大连理工大学 ， 机械工程， 2025， 硕士

【摘要】 随着国内外大型基建的蓬勃发展,对起重机的性能要求也越来越高。在全地面起重机转向时,转向系统与悬挂系统间存在复杂的耦合关系,悬挂油缸结构参数对转向操纵稳定性的影响有必要进行综合的考虑和优化。为此,以提高五轴全地面起重机的操纵稳定性为研究目标,以悬挂系统与转向系统耦合影响关系作为研究内容,对全地面起重机转向性能进行仿真与优化。论文主要研究内容如下:(1)多轴转向线性动力学建模与动特性分析。基于动力学理论构建包含侧向运动、横摆运动、侧倾运动的五轴全地面起重机三自由度转向模型,以零质心侧偏角控制理论为基础求解后三轴轮胎转角与第一轴轮胎转角的比例系数,设计比例前馈控制器,仿真对比全轴转向与前两轴转向模式在角阶跃输入下的转向响应特性,为后续非线性耦合模型的建立奠定理论基础。(2)非线性耦合动力学建模与参数敏感性研究。考虑轮胎非线性侧偏特性与油气悬挂系统刚度阻尼特性,建立包含悬挂-转向耦合作用的非线性动力学模型,以悬挂动行程和转角为模型输入变量,采用半正弦激励模拟悬挂油缸实际作业行程。运用单因素分析法揭示悬挂油缸结构参数对质心侧偏角、横摆角速度和侧倾角的影响,再通过多因素正交实验进行多参数协同优化,选取最优方案,提升起重机稳定性。(3)Adams多体动力学仿真验证。构建Adams多体动力学模型,根据第三章所得的三组正交实验方案进行仿真,对比得出方案3为最优方案。对方案3在B级、E级路面谱下进行动态转向响应分析,结果表明无论在低速还是高速状态下最优参数都使得质心侧偏角、横摆角速度和侧倾角显著降低,验证参数优化方法的有效性。(4)多目标转向控制器设计。基于最优控制理论建立以质心侧偏角、横摆角速度、侧倾角为状态变量的多目标代价函数,提出低速、中高速自适应的权重系数切换策略:低速域强化路径跟踪性能,中高速域侧重侧倾稳定性。采用粒子群算法对控制器权重矩阵参数进行优化,仿真结果表明优化后的控制系统使得质心侧偏角稳定在零值附近,横摆角速度追随理想模型,侧倾角降低,稳定性显著提升,验证了控制器的有效性。更多还原

【Abstract】 With the rapid development of large-scale infrastructure projects domestically and internationally,the performance requirements for cranes have become increasingly stringent.During the steering process of all-terrain cranes,there exists complex coupling relationships between the steering system and suspension system,necessitating comprehensive consideration and optimization of the structural parameters of suspension cylinders on steering stability.This study aims to improve the handling stability of five-axle all-terrain cranes through simulation and optimization of steering dynamics,focusing on the coupled interaction between suspension and steering systems.The main research contents are as follows:(1)Multi-axle steering linear dynamics modeling and dynamic characteristic analysis.A three-degree-of-freedom steering model incorporating lateral motion,yaw motion,and roll motion was established based on dynamic theories.Utilizing zero center of mass lateral deflection control theory,the proportional coefficient between rear three-axle tire steering angles and front axle tire angle was determined.A proportional feedforward controller was designed.Simulations comparing transient and steady-state response characteristics under angular step steering input between all-wheel steering and front-two-axle steering modes were conducted,laying theoretical foundations for subsequent nonlinear coupled model development.(2)Nonlinear coupled dynamics modeling and parameter sensitivity study.Considering tire nonlinear lateral deflection characteristics and hydro-pneumatic suspension stiffness-damping properties,a nonlinear dynamic model incorporating suspension-steering coupling was developed.Using suspension dynamic stroke and steering angle as input variables,semi-sinusoidal excitation was employed to simulate actual suspension cylinder operation.Single-factor analysis revealed the influence of stiffness-damping parameters on center of mass lateral deflection,pendulum angular velocity,and lateral inclination angle.Multi-factor orthogonal experiments enabled collaborative parameter optimization,resulting in selected optimal solutions that significantly improved crane stability.(3)Multi-body dynamics simulation and validation.An Adams multi-body dynamics model was constructed.Simulations based on three orthogonal experimental schemes from Chapter 3 identified Scheme 3 as optimal.Dynamic steering response analyses under Class B and Class E road spectra demonstrated that optimal parameters significantly reduced center of mass lateral deflection,pendulum angular velocity,and lateral inclination angle across both low and high speed conditions,validating the effectiveness of parameter optimization methods.(4)Multi-objective steering controller design.An optimal control-based multi-objective cost function with center of mass lateral deflection,pendulum angular velocity,and lateral inclination angle as state variables was established.An adaptive weight coefficient switching strategy was proposed:enhancing path-tracking performance in low-speed range while prioritizing roll stability at medium-high speeds.Particle swarm optimization algorithm optimized controller weight matrix parameters.Simulation results demonstrated optimized control system stabilized center of mass lateral deflection near zero,improved yaw rate tracking of ideal model,reduced lateral inclination angle,and significantly enhanced stability,verifying controller effectiveness.更多还原