| Strictly controlling the machining error of aero-engine blades and ensuring good profile accuracy are the keys to ensuring the machining quality of the blades,and the three-dimensional measurement of aero-engine blades is the key to evaluating the surface quality of aero-engine blades and further improving the machining process.As an offline measurement method,the traditional 3D measurement technology based on CMM has many shortcomings in the actual measurement process,such as the high measurement cost based on CMM,the difficulty in maintaining the CMM,and the introduction of secondary positioning errors,etc.,in order to make up for these deficiencies,advanced on-machine measurement technology came into being.In this context,this paper studies the key technologies of on-machine measurement of aero-engine blades.The main research contents are as follows:（1）The modeling theory and compensation method of on-machine measurement error are studied.First of all,by analyzing the many error sources that affect the on-machine measurement error,the two most important errors—geometric error of on-machine measurement and pre-travel error of on-board measurement are studied.Then,based on the theoretical derivation of the multi-body system system,a mathematical model of the geometric error of the on-board measurement is established,and a mathematical model of the pre-travel error of the on-board measurement is established based on the theoretical derivation of mechanical analysis.Secondly,the coupling analysis of the above two errors is carried out.A mathematical model of comprehensive error of on-machine measurement is presented,finally,the compensation process of comprehensive error of on-machine measurement is given in detail.（2）The on-machine measurement data acquisition process based on OPC UA is researched and implemented.Firstly,the demand analysis and system design of the on-machine measurement data acquisition system based on OPC UA were carried out.Then the on-machine measurement OPC UA information model is constructed.Secondly,the establishment of the OPC UA server and the development of the OPC UA client were carried out respectively.Finally,the prototype of the proposed on-machine measurement data acquisition system based on OPC UA is verified and tested.（3）The on-machine measurement software is researched and developed,the functional module composition and specific development process of the on-machine measurement software are analyzed in detail,and the developed functional modules are tested accordingly.The software functional modules include import and display 3D model module,three-dimensional measurement point selection and measurement path planning module,on-machine measurement comprehensive error compensation module and on-machine measurement report output module.（4）The measurement simulation and actual measurement verification of the on-machine measurement were carried out.First,the measurement simulation of the 3D probe was carried out on the basis of the simulation simulation to prevent collision safety,and on this basis,the actual on-machine measurement function verification of the blade was realized. |
