变胞机构的稳态特性与变胞构态工况自适应性研究

According to imbalance and loss of control during configuration transformation process of constrained metamorphic mechanisms, stable index of configuration transformation is defined to describe and control the instability (unreliable) problem of configuration transforming during metamorphic process, probatilistic calculation model is built to describe stable performance during configuration transforming of metamorphic mechanisms, which provides reference for stable parameter designing. On the other hand, the influence factors and change rule of configuration incontrollable behavior are studied to achieve self-adaptive of metamorphci configuration to the changing of operating condition by mechanical design and control. Based on the equivalent resistance gradient model of metamorphic mechanism proposed in previous studies, research on stable performance of metamorphic mechanism is translated into constrained force accuracy analysis and control of metamorphci joint. According to the theory and method of mechanical reliability analysis, probatilistic errors model describing the accuracy of constrained force is established and constrained force changing rule of metamorphic mechanism considering foece errors is obtained in order to provide the basis of constrained force parameter designing of constrained metamorphic joints. When metamorphic configurations are out of control and offset, random configuration changing mechanism, change rule, main influence factors and its engineering application value are analyzed to extend the application field of metamorphic mechanism. Constrained types achieving self-adaptive of metamorphci configuration to operating condition are synthesized, and constrained parameters disigning and controlling method is studied, and it provides the basis of analysis theoy and parameter design method of constrained metamorphic mechanisms which are suitable for practical application.

针对提出的约束变胞机构构态变换的失调和失控问题，引入构态变换的稳定性指标描述和调控变胞过程的构态变换的不稳定（不可靠）问题，建立变胞机构构态变换概率稳态特性的分析模型，为稳态参数设计提供依据。另一方面，研究构态失控或失控的影响因素和变化规律，进而设计和调控实现变胞构态对作业工况（如载荷等）变化的自适应。基于前期研究构建的变胞运动副等效阻力梯度模型，将变胞机构的稳定性问题，转化为变胞运动副约束力精度分析和调控问题。借鉴机构可靠性分析理论和方法，建立影响约束力精度的概率误差模型，获取约束力变化规律，为约束变胞运动副约束力参数设计提供依据。分析构态失控和失调时的随机构态变化机理，变化规律及其主要影响因素，从而为变胞机构的应用开拓新的领域。同时，探索实现变胞构态随作业工况的自适应变化的约束构型及约束参数设计和调控方法，进一步建立面向工程应用的约束变胞机构分析理论和参数设计方法的基础。

针对课题提出的约束变胞机构构态变换的失调和失控问题，首先对约束变胞源机构的构型综合理论与方法进行了研究，将作业任务分解为子任务，获取对应的变胞构态及其输出运动形式，进而获得对应的变胞运动副的类型及约束周期，构成了基于任务的变胞机构的输出运动与约束组合循环图。建立了扩展Assur杆组与变胞机构的运动形式与约束组合的关联，因而可以便捷设计出变胞源机构。应用上述提出的约束变胞机构的设计理论和方法，结合实际应用的工程特点与作业约束，首次综合设计出2种变胞机构的新结构形式，即一种具有高副机构的超高输电压线路巡检机器人变胞机构，一种开闭链（串并联）间构态转换的超高输电压线路绝缘子检测机器人变胞机构。该设计成果拓展了变胞机构的研究和应用领域，其构型综合与设计理论和方法也将成为变胞机构研究的新的研究热点。研究了影响变胞机构的运行稳定性和在外载荷力下的自适应性主要因素，对构成变胞运动副的典型接触界面的接触刚度、接触阻尼、滑动摩擦力、静摩擦系数进行分析，获取构态失控或失控的影响因素和变化规律，为变胞机构的运行稳定性和在外载荷力作用下的自适应性提供分析依据和判定准则，建立了设计和调控变胞构态对作业工况变化的自适应的理论基础。引入机械运转不均匀系数，描述构态变换的稳定性指标用以调控变胞过程的构态变换的不稳定（不可靠）问题，并将变胞机构的稳定性问题，转化为为变胞运动副约束力精度分析和调控问题。建立各类约束变胞机构的约束力精度模型的难题，转化为扩展Assur杆组的力精度模型，实现用扩展Assur杆组和/或变胞运动副的稳定性描述变胞机构的稳态特性，揭示变胞杆组及变胞运动副及其组合与变胞机构稳态特性的关联和内涵。