Dissertation > Excellent graduate degree dissertation topics show

A Study on Thermal Distortion Error Model of CL-20A CNC Lathe

Author: WuChengWei
Tutor: HuPengHao
School: Hefei University of Technology
Course: Precision instruments and machinery
Keywords: CNC machine tools Thermal error Support Vector Machine BP NeuralNetwork Least Squares method
CLC: TG519.1
Type: Master's thesis
Year: 2012
Downloads: 25
Quote: 0
Read: Download Dissertation

Abstract


CNC machine tools are widely used in modern manufacturing. With thedevelopment of science and technology, the higher accuracy of CNC machine toolis needed. Theoretical and practical research has shown that the thermal error is oneof the main obstacles and constraints the improvement of CNC accuracy. With theproject support from Ministry of Science and technology of China, CL-20AHorizontal Lathe of Dalian Machine tool Factory is chosen as research target, therelevant theoretical and experimental study has been expanded, here, the topicmainly focus on building of machine tool thermal error, which will be adopted inthe online real-time machine tool error compensation.First, many temperature sensors are pasted on the machine tool based on heatsource characteristics and distribution of machine tools, three inductance sensorsare employed to detect thermal deviation from spindle to tool position in threedirections. Then, the experimental data will be analyzed by successive regressionanalysis to identify the temperature-sensitive point and its location. With thetemperature-sensitive point, further experiment is designed and executed to find therelationship between the temperature variation of the machine sensitive point andthe thermal deviation of the spindle.The large amount obtained experimental data is analyzed by support vectormachine modeling and regression analysis. At the same time, the BP neural networkand least squares method are tested also to provide reference for Support VectorMachine method. The modeling results show that support vector machine is moresuitable for predicting the machine tool error, BP neural network and the leastsquares method has lower forecasting accuracy. Furthermore, compared to theblack-box operation and not fixed predict results of the Neural Network method,Support Vector Machine method can get the clear formula for calculation, and thetheory process is very rigorous, which will be convenient and useful to program andimplant into the NC system to achieve real-time thermal error compensationcalculation. Compared to the Least Squares method, Support Vector Machinemethod removed the redundant data, only a part of support vector used for modeling, so the generalization ability is strong.

Related Dissertations

  1. Research on Automatic Detection Algorithm for Substructure Distress of Highway Pavement Based on SVM,U418.6
  2. Research on Autamatic Music Structrue Analysis,TN912.3
  3. Research on Transductive Support Vector Machine and Its Application in Image Retrieval,TP391.41
  4. Fault Diagnosis Method Based on Support Vector Machine,TP18
  5. Process Support Vector Machine and Its Application to Satellite Thermal Equilibrium Temperature Prediction,TP183
  6. American Option Pricing under Stochastic Market Option Model Based on Dividend and Treatment Fees,O211.6
  7. Research for Infrared Image Target Identification and Tracking Technology,TP391.41
  8. Study on the Road Condition Monitoring Based on Vehicular 3D Acceleration Sensor,TP274
  9. Research of Diagnosing Cucumber Diseases Based on Hyperspectral Imaging,S436.421
  10. Research on Whispered Speaker Identification in Channel Mismatch Conditions,TN912.34
  11. Scholar Resume Automatic Generation Based on Text Mining,TP391.1
  12. Research on Intrusion Detection Based on Feature Selection,TP393.08
  13. Research on Transmembrane Protein Prediction Based on SVM,Q51
  14. Research and Application of Gas Emission Prediction Based on LS-SVM,TD712.5
  15. The Research on Intrusion Detection System Based on Machine Learning,TP393.08
  16. The New Privacy Preserving Algorithms for Linear Programming and SVMS,O221.1
  17. Dimensionality Reduction Methods for Gene Expression Data Base on SVM,TP181
  18. Prediction of Binding Affinity of Human Transporter Associated with Antigen Processing,R392.1
  19. Study on Applications of Soft Sensor in Chloromethane Recovery,TQ222.214
  20. Research of Fault Diagnosis Method of Analog Circuit Based on Improved Support Vector Machines,TN710
  21. The Forecast Methods of Mining Risk of the Coal Resources Affected by Dynamic Disaster,TD713

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metal cutting and machine tools > Turning and lathe ( lathe ) > Program control lathes and CNC lathes
© 2012 www.DissertationTopic.Net  Mobile