机器人自动钻铆技术突破了飞机装配质量和灵活性瓶颈，在装配效率和成本上有巨大优势，已成为飞机数字化、柔性化装配发展的必然选择。目前机器人钻铆系统大多以6自由度工业串联机器人为平台，此类机器人具有结构弱刚性的固有缺点，在钻铆作业过程中承受较大的压紧力和制孔力等载荷时，机器人末端和执行器会发生一定的变形甚至颤振，严重影响钻铆精度和质量。该文以钻铆机器人为对象建立机器人静刚度模型，设计关节刚度辨识实验获取了机器人关节刚度值，进一步结合刚度性能评价指标分析了机器人工作空间范围内刚度性能分布特征，根据实际作业工况，采用粒子群算法对机器人进行位姿优化，从而增强了机器人刚度性能，对于保证系统作业稳定性和作业质量具有重要意义。
Automatic robotic drilling and riveting greatly improve aircraft assembly quality and flexibility while reducing costs, so automatic drilling and riveting are being widely used for aircraft assembly. However, almost all robotic drilling and riveting systems are based on six degrees of freedom serial robots. However, these robots have an inherent weakness due to their poor rigidity. Large pressing and drilling forces during drilling and riveting can lead to deformation and even flutter of the robot end actuator, which seriously affect the drilling and riveting accuracy and quality. A static stiffness model of a drilling and riveting robot is developed with joint stiffness measurements to predict robot joint stiffnesses. A stiffness evaluation index is then used to characterize the robotic arm stiffness in the working space. The stiffness index can be used to optimize the robot position and posture for a specific operation using a particle swarm algorithm to improve the stiffness. This improves the system stability and quality.
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