TY - JOUR
T1 - Deterioration of form accuracy induced by servo dynamics errors and real-time compensation for slow tool servo diamond turning of complex-shaped optics
AU - Huang, Peng
AU - Wu, Xiaoyu
AU - To, Suet
AU - Zhu, Li Min
AU - Zhu, Zhiwei
N1 - Funding Information:
This work is jointly supported by the National Natural Science Foundation of China ( 51705254 ), the Natural Science Foundation of Jiangsu Province ( BK20170836 ), the Young Innovation Talents Program of Universities in Guangdong Province ( 2018KQNCX217 ), the State Key Laboratory of Mechanical Systems and Vibration ( MSV202006 ), the European Commission/Research Grants Council Collaboration Scheme ( E-PolyU502/17 ), and the European Unions Horizon 2020 Research and Innovation Program ( 767589 ).
Funding Information:
This work is jointly supported by the National Natural Science Foundation of China (51705254), the Natural Science Foundation of Jiangsu Province (BK20170836), the Young Innovation Talents Program of Universities in Guangdong Province (2018KQNCX217), the State Key Laboratory of Mechanical Systems and Vibration (MSV202006), the European Commission/Research Grants Council Collaboration Scheme (E-PolyU502/17), and the European Unions Horizon 2020 Research and Innovation Program (767589).
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/7
Y1 - 2020/7
N2 - Tool servo diamond turning is a promising method for generating complex-shaped optics. Considering the dynamic oscillation of the tool, servo dynamics are essential for the accuracy of the form generated with tool servo turning. Although static geometric errors and multiple compensation strategies for these errors have been studied extensively, the effects of dynamics errors of the servo axis on surface quality have received less attention. In this study, a dynamic surface generation model is established by considering the coupling effect between the servo axis dynamics and the cutting force. Using a micro-lens array (MLA) as an example, the components of the servo dynamics error of the servo motion, including dynamic deformation, resonant vibration, and trajectory tracking error, are characterised. The relationship between the servo dynamics error and the resulting form error is then theoretically identified with experimental verification. To compensate for the servo dynamics error in real-time, the concept of a cooperative tool servo (CTS) is proposed by incorporating a slow tool servo (STS) into a fast tool servo using a master-slave control strategy. Relative to using a STS for turning an MLA, the peak-to-valley (PV) servo motion error when using a CTS decreases from 4.8 μm to 0.3 μm experimentally, and the corresponding PV form error for one hexagonal lenslet decreases from 4 μm to 1.4 μm, demonstrating the effectiveness and superiority of a CTS for dynamics error compensation in the manufacturing of complex-shaped optics.
AB - Tool servo diamond turning is a promising method for generating complex-shaped optics. Considering the dynamic oscillation of the tool, servo dynamics are essential for the accuracy of the form generated with tool servo turning. Although static geometric errors and multiple compensation strategies for these errors have been studied extensively, the effects of dynamics errors of the servo axis on surface quality have received less attention. In this study, a dynamic surface generation model is established by considering the coupling effect between the servo axis dynamics and the cutting force. Using a micro-lens array (MLA) as an example, the components of the servo dynamics error of the servo motion, including dynamic deformation, resonant vibration, and trajectory tracking error, are characterised. The relationship between the servo dynamics error and the resulting form error is then theoretically identified with experimental verification. To compensate for the servo dynamics error in real-time, the concept of a cooperative tool servo (CTS) is proposed by incorporating a slow tool servo (STS) into a fast tool servo using a master-slave control strategy. Relative to using a STS for turning an MLA, the peak-to-valley (PV) servo motion error when using a CTS decreases from 4.8 μm to 0.3 μm experimentally, and the corresponding PV form error for one hexagonal lenslet decreases from 4 μm to 1.4 μm, demonstrating the effectiveness and superiority of a CTS for dynamics error compensation in the manufacturing of complex-shaped optics.
KW - Cooperative tool servo
KW - Micro-structured optics
KW - Servo dynamic error
KW - Ultra-precision diamond turning
UR - http://www.scopus.com/inward/record.url?scp=85083713293&partnerID=8YFLogxK
U2 - 10.1016/j.ijmachtools.2020.103556
DO - 10.1016/j.ijmachtools.2020.103556
M3 - Journal article
AN - SCOPUS:85083713293
SN - 0890-6955
VL - 154
JO - International Journal of Machine Tools and Manufacture
JF - International Journal of Machine Tools and Manufacture
M1 - 103556
ER -