Control of a Flexible Manipulator Using Hierarchical Multi-processors

使用分层多处理器控制柔性机械手

• 批准号: 60460110
• 负责人: YOSHIMOTO Kenichi
• 金额: $ 4.61万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60460110/
• 关键词: Flexible Manipulator; Flexible Link; Finite Dimensional Model; Optimal Type I Servomechanism; 分散階層制御系

Conventionally, the positioning accuracy of robot manipulators has been improved by increasing the rigidity of the system. A high rigidity, however, results in an increase in mass which leads to deterioration in efficiency and high-speed behaviour. By developing a control strategy in which the flexibility of the link is taken into account, we can design a light manipulator with high positioning accuracy. This paper presents a real-time control system using hierarchical multi-processors with a state feedback for each joint. Using this flexible manipulator system, a precise control at high working speed is demonstrated. The outcome of this research is summerized as follows:1. A simple mathematical model of the flexible manipulator which considers only the first mode of the link proved to be sufficiently accurate, whereas a precise model considering higher modes is extremely complicated and therefore not suitable for control purposes.2. In linearing the equation, non-linear feedback was partially introduced. This gave better results than a simple linear expansion around the equilibrium point.3. Dynamic feedback of link deformation proved to be an effective means of active damping.4. Compensation of Coulomb's friction by feedforward was effective in improving positioning accuracy and damping the residual elastic vibration.5. In order to achieve further precision in positioning and to compensate for changes in payload or friction, a type I servomechanism was implemented for each joint.6. In the designing process, the control system was reduced by means of modal decomposition neglecting high-order vibration modes caused by interference between different modes. Nevertheless, the manipulator for this study had no trouble with respect to spillover because of its sufficient structural damping.

通常，通过提高系统的刚度，可以提高机器人操纵器的定位精度。然而，高刚度会导致质量增加，从而导致效率和高速行为恶化。通过制定控制链接灵活性的控制策略，我们可以设计具有高定位精度的轻型操纵器。本文使用分层多处理器提出了一个实时控制系统，每个关节都有状态反馈。使用此灵活的操纵器系统，展示了高工作速度的精确控制。这项研究的结果如下：1。仅考虑链接的第一个模式的灵活操纵器的简单数学模型被证明是足够准确的，而考虑到较高模式的精确模型非常复杂，因此不适合控制目的。2。在线方程式中，部分引入了非线性反馈。这比在平衡点周围的简单线性扩展提供了更好的结果。3。链路变形的动态反馈被证明是有效的主动阻尼手段。4。通过进料对库仑摩擦的补偿可有效提高定位准确性和阻尼残留弹性振动。5。为了在定位方面取得进一步的准确性并弥补有效载荷或摩擦的变化，为每个关节实施了I型伺服机制6。在设计过程中，通过模态分解减少了控制系统，从而忽略了由不同模式之间的干扰引起的高阶振动模式。然而，由于其足够的结构阻尼，这项研究的操纵器在溢出方面没有任何麻烦。