工业机器人火箭喷管冷却通道线激光在位测量系统开发

Development of in-situ line-laser measurement system for cooling channel of rocket nozzle based on industrial robot

针对液体火箭发动机喷管现有的人工检测方式无法实现喷管全域几何特征快速高精度测量的问题,设计并开发一套基于工业机器人和线激光的火箭发动机喷管冷却通道几何特征在位测量系统。建立基于工业机器人和线激光的测量系统运动学模型,研究基于空间定点约束的手眼参数辨识方法,根据火箭喷管冷却通道的几何特征与测量需求规划线激光扫描路径,提出基于最大类间方差法的喷管冷却通道关键尺寸计算算法,基于C++语言和Qt框架开发出具备系统标定、测量路径规划、关键尺寸计算、测量结果分析与技术报告输出等功能的软件系统。采用带有通道特征的试验样件和某型号火箭发动机喷管进行综合试验验证,结果表明:该系统对通道的筋宽测量精度为0.025 mm,对通道的槽深测量精度为0.018 mm,单个测点测量用时30 ms,满足火箭发动机喷管全域几何特征快速高精度检测的需求。

Aiming at the problem that the existing manual detection method of liquid rocket engine nozzle cannot realize the rapid and high precision measurement of the global geometric characteristics of the nozzle,a set of in-situ measurement system of the geometric characteristics of the nozzle cooling channel of the rocket engine is designed and developed based on industrial robots and line-laser.The kinematic model of measurement system based on industrial robot and line-laser is established,the identification method of handeye parameters based on space fixed point constraint is studied,the linear laser scanning path is planned according to the geometric characteristics and measurement requirements of the rocket nozzle cooling channel,and the key size calculation algorithm of the nozzle cooling channel is proposed based on the maximum class variance method.Based on C++language and Qt framework,a software system with functions such as system calibration,robot and turntable measurement path control,key dimension calculation,measurement result analysis and technical report output is developed.The test samples with flow channel characteristics and a rocket engine nozzle were used for comprehensive test verification.The results show that the measurement accuracy of the system is 0.025 mm for the width of the flow channel,0.018 mm for the depth of the flow channel,and 30 ms for a single measuring point to measure,which meets the requirements of rapid and high precision detection of the global geometric characteristics of the rocket engine nozzle.