面向航空部件高精度作业的机器人刚度强化机制与轨迹补偿方法

Currently, using industry robot in high value-added processing tasks is a research hotspot, and high requirements have been presented in cutting performance and trajectory accuracy. The project aims at systematic research in robotic stiffness strengthening mechanism and trajectory compensation method, and breaking the using limitation in aviation product high accuracy operation which result from the weak stiffness property and low trajectory accuracy. An analytical stiffness model for certain direction is established, according to distribution character of cutting force. The equivalent stiffness model under pressing force is established, and the function mechanism of pressing force to intensify the robotic stiffness performance is researched. Combine the kinematics and stiffness performance evaluated model, a robotic configuration comprehensive optimization method is raised on the basis of redundant degree of freedom. An online prediction and compensation method of robotic processing trajectory deviation is come up with by collecting and analyzing robotic force characteristics. A robot high precision control strategy is studied based on the closed loop feedback technology of robotic joints, and the joint deviations are on-line detection and self-adaption modification, so the accuracy of robotic trajectory could be guaranteed, and the adaptability to the processing environment could be improved. The research results of the project have a great significance to enrich the theoretical system of high-precision robot operation and promote the application of industrial robots in high-precision manufacturing field.

工业机器人应用于高附加值的精加工领域是当前机器人技术研究热点，对机器人切削性能与轨迹精度都提出了更高要求。本项目旨在系统研究机器人刚度强化机制与轨迹补偿方法，突破机器人由于弱刚性属性与低轨迹精度在航空产品高精度作业中的使用限制。根据加工过程切削载荷的分布特性，建立机器人定向刚度解析模型；建立压紧状态下的等效刚度模型，研究压紧力对机器人刚度强化的作用机理；结合运动学与刚度评估模型，提出基于冗余自由度的机器人姿态综合优化方法。通过在线采集与分析加工过程中的机器人受力特性，研究机器人加工轨迹偏差在线预测与补偿方法；基于关节闭环反馈技术提出机器人高精度控制策略，实现机器人关节转角误差在线监测与自适应修正，从而保障机器人运动轨迹精度，并提高对加工环境的适应性。研究成果对丰富机器人高精度作业理论体系并推进工业机器人在高精度制造领域的应用具有重要意义。

工业机器人作为一种智能、柔性加工载体，在飞机装配领域中具有广泛的应用前景。然而受其串联结构固有特性的影响，其刚度仅是数控机床的1/50~1/20，甚至更低。对于面向高精度加工领域的工业机器人，机器人本体刚度特性会造成加工精度与加工质量缺陷。本项目以工业机器人自动加工系统为研究对象，重点分析机器人刚度特性对制孔、铣削过程的作用机理，为分析机器人制孔过程、寻求提升机器人加工性能的方法奠定理论基础。研究了辅助末端压紧的机器人作业刚度强化机制，形成了刚度最优与作业稳定性导向的机器人作业姿态综合规划方法，实现了机器人复杂加工轨迹高精度控制及在线自适应补偿。本项目成果为提高机器人作业刚性提供了新的解决方案，并成功应用于机器人高精度制孔/铣削系统，推动了以工业机器人为柔性加工载体的先进制造装备在高端制造领域的推广应用。