Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing pr...Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing precondition.In this paper, a new four-sensor method with an improved measurement system is proposed to on-machine separate the straightness and tilt errors of a linear slideway from the sensor outputs, considering the influences of the reference surface profile and the zero-adjustment values. The improved system is achieved by adjusting a single sensor to di erent positions. Based on the system, a system of linear equations is built by fusing the sensor outputs to cancel out the e ects of the straightness and tilt errors. Three constraints are then derived and supplemented into the linear system to make the coe cient matrix full rank. To restrain the sensitivity of the solution of the linear system to the measurement noise in the sensor outputs, the Tikhonov regularization method is utilized. After the surface profile is obtained from the solution, the straightness and tilt errors are identified from the sensor outputs. To analyze the e ects of the measurement noise and the positioning errors of the sensor and the linear slideway, a series of computer simulations are carried out. An experiment is conducted for validation, showing good consistency. The new four-sensor method with the improved measurement system provides a new way to measure the straightness and tilt errors of a linear slideway, which can guarantee favorable propagations of the residuals induced by the noise and the positioning errors.展开更多
The purpose of this study is to develop a Web-based on-machine mould identification and measurement system. The Web-based mould identification system matches obtained vision information with CAD database. Developed We...The purpose of this study is to develop a Web-based on-machine mould identification and measurement system. The Web-based mould identification system matches obtained vision information with CAD database. Developed Web-based system is to exchange messages between a server and a client by making of ActiveX control, and the result of mould identification is shown on Web-browser at remote site. For effective feature classification and extraction, the signature method is used to make meaningful information from obtained image data. For on-machine measurement of the matched mould, inspection database is constructed from CAD database using developed inspection planning methods. The results are simulated and analyzed using developed system to verify the effectiveness of the proposed methods.展开更多
Parts with high-quality freeform surfaces have been widely used in industries,which require strict quality control during the manufacturing process.Among all the industrial inspection methods,contact measurement with ...Parts with high-quality freeform surfaces have been widely used in industries,which require strict quality control during the manufacturing process.Among all the industrial inspection methods,contact measurement with coordinate measuring machines or computer numerical control machine tool is a fundamental technique due to its high accuracy,robustness,and universality.In this paper,the existing research in the contact measurement field is systematically reviewed.First,different configurations of the measuring machines are introduced in detail,which may have influence on the corresponding sampling and inspection path generation criteria.Then,the entire inspection pipeline is divided into two stages,namely the pre-inspection and post-inspection stages.The typical methods of each sub-stage are systematically overviewed and classified,including sampling,accessibility analysis,inspection path generation,probe tip radius compensation,surface reconstruction,and uncertainty analysis.Apart from those classical research,the applications of the emerging deep learning technique in some specific tasks of measurement are introduced.Furthermore,some potential and promising trends are provided for future investigation.展开更多
As crucial parts of an aeroengine,blades are vulnerable to damage from long-term operation in harsh environments.The ultrasonic surface rolling process(USRP)is a novel surface treatment technique that can highly impro...As crucial parts of an aeroengine,blades are vulnerable to damage from long-term operation in harsh environments.The ultrasonic surface rolling process(USRP)is a novel surface treatment technique that can highly improve the mechanical behavior of blades.During secondary machining,the nominal blade model cannot be used for secondary machining path generation due to the deviation between the actual and nominal blades.The clamping error of the blade also affects the precision of secondary machining.This study presents a two-sided USRP(TS-USRP)machining for aeroengine blades on the basis of on-machine noncontact measurement.First,a TS-USRP machining system for blade is developed.Second,a 3D scanning system is used to obtain the point cloud of the blade,and a series of point cloud processing steps is performed.A local point cloud automatic extraction algorithm is introduced to extract the point cloud of the strengthened region of the blade.Then,the tool path is designed on the basis of the extracted point cloud.Finally,an experiment is conducted on an actual blade,with results showing that the proposed method is effective and efficient.展开更多
In this study, an air-bearing capacitive linear variable differential transformer （LVDT）-like contact sensor with a rounded diamond tip was mounted to a desktop machine tool to construct an on-machine （OM） measuri...In this study, an air-bearing capacitive linear variable differential transformer （LVDT）-like contact sensor with a rounded diamond tip was mounted to a desktop machine tool to construct an on-machine （OM） measuring system. The measuring system was capable of decoding the digital signals of linear encoders mounted on the machine tool and acquiring the analog signal of the contact sensor. To verify the measuring system, experimental examinations were performed on an oxygen-free copper （OFC） convex aspheric mold with a diameter of 5 mm and a curve height of 0.46 mm. The acquired signals were processed by the implemented Gaussian regression filter （GRF）, removing the tilt of measured profile, and compensating for the radius of probe tip. The profile obtained was compared to that measured using a commercially available device, and a maximum deviation of 14.6μm was found for the rough cutting. The compensation cutting was then performed according to the form error of OM measurement. As a result, the PV form error compared with the designed profile was reduced from 19.2μm over a measured diameter of 4 mm to 9.7 μm over a measured diameter of 3.1 mm, or a percentage improvement of 35.4% in form accuracy. Through the examination for aspheric machining, the effectiveness of the implemented OM measuring system was demonstrated, and the technical details of system implementation were presented. Further improvement was suggested to reduce the diameter of probe tip and measuring force.展开更多
The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining.However,current on-machine measurement methods cannot precisely obtain the tool nose radius an...The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining.However,current on-machine measurement methods cannot precisely obtain the tool nose radius and wear.This study therefore investigated the onmachine measurement of tool nose radius on the order of hundreds of microns and wear on the order of a few microns to tens of microns during precision/ultra-precision machining using the edge reversal method.To provide the necessary replication,pure aluminum and pure copper soft metal substrates were evaluated,with pure copper exhibiting superior performance.The feasibility of the measurement method was then demonstrated by evaluating the replication accuracy using a 3D surface topography instrument;the measurement error was only 0.1%.The wear of the cutting tool was measured using the proposed method to obtain the maximum values for tool arc wear,flank wear,and wear depth of 3.4 lm,73.5 lm and 3.7 lm,respectively.展开更多
The machining accuracy of the curved surfaces of integrated turbine blades directly determines the performance and service life of the turbojet engine system.In this paper,a non-contact on-machine measurement system i...The machining accuracy of the curved surfaces of integrated turbine blades directly determines the performance and service life of the turbojet engine system.In this paper,a non-contact on-machine measurement system is developed for precision milling of integrated turbines to reduce the impact of workpiece deformation,overcutting,tool chatter,and material work hardening.Milling with the on-machine measurement system obtained high-quality integrated turbine surfaces.The geometric accuracy error(PV)is below 3μm,and the surface roughness(Ra)is less than 2μm.The processed integrated turbine blade can achieve the accuracy requirements in the design and manufacturing and can be practically applied to the entire turbojet engine.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51435006)
文摘Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing precondition.In this paper, a new four-sensor method with an improved measurement system is proposed to on-machine separate the straightness and tilt errors of a linear slideway from the sensor outputs, considering the influences of the reference surface profile and the zero-adjustment values. The improved system is achieved by adjusting a single sensor to di erent positions. Based on the system, a system of linear equations is built by fusing the sensor outputs to cancel out the e ects of the straightness and tilt errors. Three constraints are then derived and supplemented into the linear system to make the coe cient matrix full rank. To restrain the sensitivity of the solution of the linear system to the measurement noise in the sensor outputs, the Tikhonov regularization method is utilized. After the surface profile is obtained from the solution, the straightness and tilt errors are identified from the sensor outputs. To analyze the e ects of the measurement noise and the positioning errors of the sensor and the linear slideway, a series of computer simulations are carried out. An experiment is conducted for validation, showing good consistency. The new four-sensor method with the improved measurement system provides a new way to measure the straightness and tilt errors of a linear slideway, which can guarantee favorable propagations of the residuals induced by the noise and the positioning errors.
基金Project (No. KRF-2005-202-D00046) supported by the Korea Re-search Foundation
文摘The purpose of this study is to develop a Web-based on-machine mould identification and measurement system. The Web-based mould identification system matches obtained vision information with CAD database. Developed Web-based system is to exchange messages between a server and a client by making of ActiveX control, and the result of mould identification is shown on Web-browser at remote site. For effective feature classification and extraction, the signature method is used to make meaningful information from obtained image data. For on-machine measurement of the matched mould, inspection database is constructed from CAD database using developed inspection planning methods. The results are simulated and analyzed using developed system to verify the effectiveness of the proposed methods.
基金partially supported by the Natural Science Foundation of Shanghai(Grant No.22ZR1435200)the National Natural Science Foundation of China(Grant No.52075337)the Open Research Fund of State Key Laboratory of Digital Manufacturing and Equipment Technology,HUST(Grant No.DMETKF2022010)。
文摘Parts with high-quality freeform surfaces have been widely used in industries,which require strict quality control during the manufacturing process.Among all the industrial inspection methods,contact measurement with coordinate measuring machines or computer numerical control machine tool is a fundamental technique due to its high accuracy,robustness,and universality.In this paper,the existing research in the contact measurement field is systematically reviewed.First,different configurations of the measuring machines are introduced in detail,which may have influence on the corresponding sampling and inspection path generation criteria.Then,the entire inspection pipeline is divided into two stages,namely the pre-inspection and post-inspection stages.The typical methods of each sub-stage are systematically overviewed and classified,including sampling,accessibility analysis,inspection path generation,probe tip radius compensation,surface reconstruction,and uncertainty analysis.Apart from those classical research,the applications of the emerging deep learning technique in some specific tasks of measurement are introduced.Furthermore,some potential and promising trends are provided for future investigation.
基金The authors gratefully acknowledge the financial support extended by the National Natural Science Foundation of China(Grant Nos.51975214,51725503,and 51575183)the 111 Project.Zhang X C is also grateful for the support by the Major Program of the National Natural Science Foundation of Shanghai(Grant No.2019-01-07-00-02-E00068).
文摘As crucial parts of an aeroengine,blades are vulnerable to damage from long-term operation in harsh environments.The ultrasonic surface rolling process(USRP)is a novel surface treatment technique that can highly improve the mechanical behavior of blades.During secondary machining,the nominal blade model cannot be used for secondary machining path generation due to the deviation between the actual and nominal blades.The clamping error of the blade also affects the precision of secondary machining.This study presents a two-sided USRP(TS-USRP)machining for aeroengine blades on the basis of on-machine noncontact measurement.First,a TS-USRP machining system for blade is developed.Second,a 3D scanning system is used to obtain the point cloud of the blade,and a series of point cloud processing steps is performed.A local point cloud automatic extraction algorithm is introduced to extract the point cloud of the strengthened region of the blade.Then,the tool path is designed on the basis of the extracted point cloud.Finally,an experiment is conducted on an actual blade,with results showing that the proposed method is effective and efficient.
文摘In this study, an air-bearing capacitive linear variable differential transformer （LVDT）-like contact sensor with a rounded diamond tip was mounted to a desktop machine tool to construct an on-machine （OM） measuring system. The measuring system was capable of decoding the digital signals of linear encoders mounted on the machine tool and acquiring the analog signal of the contact sensor. To verify the measuring system, experimental examinations were performed on an oxygen-free copper （OFC） convex aspheric mold with a diameter of 5 mm and a curve height of 0.46 mm. The acquired signals were processed by the implemented Gaussian regression filter （GRF）, removing the tilt of measured profile, and compensating for the radius of probe tip. The profile obtained was compared to that measured using a commercially available device, and a maximum deviation of 14.6μm was found for the rough cutting. The compensation cutting was then performed according to the form error of OM measurement. As a result, the PV form error compared with the designed profile was reduced from 19.2μm over a measured diameter of 4 mm to 9.7 μm over a measured diameter of 3.1 mm, or a percentage improvement of 35.4% in form accuracy. Through the examination for aspheric machining, the effectiveness of the implemented OM measuring system was demonstrated, and the technical details of system implementation were presented. Further improvement was suggested to reduce the diameter of probe tip and measuring force.
基金the financial support provided by the National Key Research and Development Program(Grant No.2018YFA0702900)the National Natural Science Foundation of China(Grant No.51975096).
文摘The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining.However,current on-machine measurement methods cannot precisely obtain the tool nose radius and wear.This study therefore investigated the onmachine measurement of tool nose radius on the order of hundreds of microns and wear on the order of a few microns to tens of microns during precision/ultra-precision machining using the edge reversal method.To provide the necessary replication,pure aluminum and pure copper soft metal substrates were evaluated,with pure copper exhibiting superior performance.The feasibility of the measurement method was then demonstrated by evaluating the replication accuracy using a 3D surface topography instrument;the measurement error was only 0.1%.The wear of the cutting tool was measured using the proposed method to obtain the maximum values for tool arc wear,flank wear,and wear depth of 3.4 lm,73.5 lm and 3.7 lm,respectively.
基金the financial support from National Natural Science Foundation of China(Nos.51775046&51875043&52005040)Beijing Municipal Natural Science Foundation(No.JQ20014).
文摘The machining accuracy of the curved surfaces of integrated turbine blades directly determines the performance and service life of the turbojet engine system.In this paper,a non-contact on-machine measurement system is developed for precision milling of integrated turbines to reduce the impact of workpiece deformation,overcutting,tool chatter,and material work hardening.Milling with the on-machine measurement system obtained high-quality integrated turbine surfaces.The geometric accuracy error(PV)is below 3μm,and the surface roughness(Ra)is less than 2μm.The processed integrated turbine blade can achieve the accuracy requirements in the design and manufacturing and can be practically applied to the entire turbojet engine.
