A two-phased object orientation controller on soft finger operations
A two-phased object orientation controller on soft finger operations
复制标题
软手指操作的两阶段对象定向控制器
DOI：
10.1109/iros.2007.4399136
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
S. Hirai
中科院分区：
文献类型：
--
作者：
T. Inoue;S. Hirai
软指操作的最大特点是在操作过程中的柔软性和灵活性。在以往的工作中，从物理和力学的角度对这种本征性质进行了定量的解释，即由大的弹性变形引起的变形能自动存在一个最小平衡点。因此，本文首先在能量分析的基础上推导出两指软指机械手的运动方程，并解释了即使在用手操作运动的情况下，组合能量函数上也存在一个平衡点。在本文中，平衡点被称为LMEEwC，它被展开为有约束的弹性能量的局部最小值。接下来，我们证明了通过应用与手的每个关节角度相关联的两相控制器，可以很容易地实现对被最小自由度的手抓住的刚性对象的姿态控制，这是本报告中新提出的。该控制方案由两部分组成：关于手指角度的PD控制器和关于被抓取物体方向的积分控制器。后一部分控制方法的特点是，手的期望关节角由积分控制器相对于对象方向动态产生。最后，在软指操作的情况下，验证了该控制方法的有效性。
The greatest characteristic of soft-fingered manipulation is its softness and flexibility during manipulating operations. In previous works, this intrinsic property had been quantitatively explained from the viewpoint of physical and mechanical perspective that the deformation energy induced by large elastic distortion automatically has a minimum equilibrium point. Hence this report first derive equations of motion of two-fingered soft finger robotic hand on the basis of energy- based analysis, and explain that an equilibrium point on a combined energy function exists even in the case of manipulating motions by the hand. In this paper, the equilibrium point is called LMEEwC that is unfolded as local minimum of elastic energy with constraints. Next, we show that the posture control of a rigid object grasped by the minimal degrees-of-freedom hand can easily be achieved by applying a two-phased controller associated with each joint angle of the hand, which is newly proposed in this report. This control scheme is constructed by two parts: a PD controller with respect to the finger angle and an integral controller with respect to the orientation of the grasped object. The characteristics of the control method of the latter part is that the desired joint angle of the hand is produced dynamically by the integral controller with respect to the object orientation. Finally, we clarify the effectiveness of the proposed control method in the case of the soft-fingered manipulation.