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.

以往，通过提高系统的刚性来提高机器人操作器的定位精度。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。通过开发一种控制策略，其中的灵活性的链接被考虑在内，我们可以设计一个光机械手具有高定位精度。本文提出了一个实时控制系统，采用分层多处理器与状态反馈的每个关节。使用这种柔性机械手系统，在高工作速度下的精确控制被证明。本研究的主要成果如下：1.一个简单的数学模型的柔性机械手，只考虑第一模式的链接被证明是足够准确的，而一个精确的模型，考虑到更高的模式是非常复杂的，因此不适合于控制业务。在对方程进行线性化时，部分地引入了非线性反馈。这给出了比平衡点附近的简单线性展开更好的结果。连杆变形的动力反馈被证明是一种有效的主动阻尼手段.采用前馈补偿库仑摩擦力，可以有效地提高定位精度和抑制残余弹性振动.为了进一步提高定位精度，并补偿有效载荷或摩擦力的变化，每个关节都采用了I型伺服机构。6.在设计过程中，采用模态分解的方法对控制系统进行了简化，忽略了模态间相互干扰引起的高阶振动模态。然而，本研究的机械手没有溢出方面的问题，因为它有足够的结构阻尼。