Combined Structural and Dimensional Synthesis of Task Redundant Robot Manipulators

迄今为止，关于结构和尺寸综合的研究活动仅涉及无冗余的特定任务机器人。该项目的目的是研究建模和选择方法，以便为工业中部署的机器人提供更多的替代方案，提高效率，并通过考虑特定领域的条件，更大规模地开辟医疗技术等应用领域。该项目专注于具有五个定义自由度（DoF）的任务，例如钻孔、铣削、焊接或激光切割，其中旋转对称导致末端执行器DoF的一个冗余度（任务冗余度）。更多DoF的存在既有缺点（更多致动器，因此更高的能耗、质量和成本），也有优点（冗余度增加了工作空间，有助于避免奇异性）。这些优点和缺点的自动平衡以及与现有结构的比较必然导致使用冗余结构，如果它们对相应的任务有利的话。因此，使用尺寸较小的标准机器人，它们在结构上具有比任务所需的更多的末端执行器DoF（任务冗余），并且尺寸过大。虽然这些机器人满足运动学的要求，如碰撞和奇异的自由工作空间，他们的能量消耗是高于必要的，由于较大的质量和额外的drivers.The建议的目的是扩展的冗余分辨率的方法相结合的结构和尺寸合成的特定任务的机器人。这将启用针对给定任务优化尺寸的任务冗余运动学。这导致机器人在尺寸上具有特定的任务，但由于冗余，它们的结构并不特定。要包括在比较中的结构的任务冗余允许通过不影响任务本身的零空间移动来优化性能特性。与非冗余运动学相比，使用任务冗余来增加性能特性必须已经发生在结构的尺寸合成中，因为这种类型的冗余的潜力强烈地依赖于机器人的尺寸。冗余为影响尺寸合成的更高级别目标函数的逆运动学问题的解决方案提供了自由度。由于在冗余解析中，一个（可能是另一个）目标函数被优化，因此必须找到级联优化（维度合成和冗余解析）之间的相互作用，以使两个级别能够相互补充。拟议项目的重点是将方法从运动学转移到任务冗余和开发优化结构。

Research activities on the combined structural and dimensional synthesis so far only have dealt with task-specific robots without redundancy. The aim of this project is to investigate modelling and selection methods in order to offer more alternatives for robots deployed in industry, to enable efficiency increases and to open up fields of application such as medical technology on a larger scale by taking into account field-specific conditions. The project focuses on tasks with five defined degrees of freedom (DoF), e.g. drilling, milling, welding or laser cutting, where rotational symmetry leads to one degree of redundancy of the end effector DoF (task redundancy).The presence of more DoF offers both disadvantages (more actuators, thus higher energy consumption, mass, costs) and advantages (redundancy increases the workspace and helps avoiding singularities). The automated balancing of these advantages and disadvantages and the comparison with existing structures perspectively leads to the use of redundant structures, if they are advantageous for the respective task. As a result, less oversized standard robots are used, which both have structurally more end-effector DoF than necessary for the task (task redundancy) and are oversized in their dimensions. Although these robots fulfill kinematic requirements such as a collision- and singularity-free workspace, their energy consumption is higher than necessary due to the larger masses and additional drives.The aim of the proposal is to extend the methods for redundancy resolution for the combined structural and dimensional synthesis of task-specific robots. This enables task-redundant kinematics whose dimensions are optimized for a given task. This results in robots that are task specific in their dimensions, but not – due to redundancy – in their structure. The task redundancy of the structures to be included in the comparison allows the optimization of performance characteristics through null space movements that do not influence the task itself. The use of task redundancy to increase the performance characteristics compared to non-redundant kinematics must already take place in the dimensional synthesis of the structures, since the potential of this type of redundancy depends strongly on the dimensioning of the robot.The redundancy provides a degree of freedom for the solution of the inverse kinematics problem which influences the higher-level objective function of the dimensional synthesis. Since in the redundancy resolution one (possibly other) objective function is optimized, interactions between the cascaded optimizations (dimensional synthesis and redundancy resolution) have to be found to enable the two levels to complement each other. The focus of the proposed project is a transfer of methods from kinematic to task redundancy and the development of the optimization structures.