Abstract
Localisation of workpieces with large sculptured surfaces can be difficult. Previously, such pieces were measured by the probe of the machine and adjusted manually. This process is arduous and time-consuming and an even allowance cannot be ensured for every measured point. Searching for the optimal location of surface matching by computer can realise computer aided localisation (CAL) and thus enhance the precision of localisation, saving a lot of time and greatly accelerating machining cycles while reducing machining cost.
In this paper, a method is proposed for a localisation problem that consists of rough surface matching and accuracy surface matching. Rough matching determines the variable range of the follow-up algorithms. Accuracy matching acquires the optimal location. Then fast localisation and a clamp can be implemented. A hybrid global optimisation method is adopted to cope with the accuracy matching. It shares the advantages of both genetic algorithms (GAs) and simplex algorithms. The method presented in this paper has been used in the 5-axis machining of both large Kaplan and Francis hydro turbine blades. It shows that the method is easy to realise and the algorithm is steady and robust.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Li ZX, Gou JB, Chu YX (1998) Geometric algorithms for workpiece localisation. IEEE Trans Robot Automat 14(6):864–878
Chu YX, Gou JB, Li ZX (1998) On the hybrid workpiece localisation/envelopment problems. In: Proceedings of IEEE international conference on robot automation 1998, pp 3665–3670
Li XM, Yeung M, Li ZX (1996) An algebraic algorithm for workpiece localisation. In: Proceedings of IEEE international conference on robot automation 1996, pp 152–158
Gou JB, Chu YX, Li ZX (1998) On the symmetric localisation problem. IEEE Trans Robot Automat 14(4):533–540
Chu YX, Gou JB, Li ZX (2000) On hybrid workpiece localisation/envelopment problems. Chin J Mech Eng 36(1):45–49 (in Chinese)
Esat II, Bahai H (2000) Surface alignment based on the moment of inertia and improved least-squares methods. In: Proceedings of Inst Mech Eng 214B(B7):547–554
Surazhsky T, Elber G (2001) Shape blending matching free-form surfaces. Comput Graphic 25:3–12
Arun KS, Huang TS, Blostein SD (1987) Least-squares fitting of two 3-D point sets. IEEE Trans Pattern Anal 9:698–700
Brockett RW (1989) Least squares matching problems. Linear Algebra Appl 1222(123,124):761–777
Michalewicz Z (1992) Genetic algorithms + data structure =evolution. Springer, Berlin Heidelberg New York
Liu WX (1994) Optimal design for mechanics. Tsinghua University Press
Acknowledgements
This work was supported by Dongfang Electrical Machinery Co. Ltd., and the large hydro turbine blades were machined there. The authors greatly appreciated the support.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Sijie, Y., Yunfei, Z., Fangyu, P. et al. Research on the localisation of the workpieces with large sculptured surfaces in NC machining. Int J Adv Manuf Technol 23, 429–435 (2004). https://doi.org/10.1007/s00170-003-1897-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00170-003-1897-2