• Silviya Salapateva Faculty of Mechanical Engineering,Technical University of Sofia, Plovdiv Branch (BG)
  • Iliya Chetrokov Faculty of Mechanical Engineering,Technical University of Sofia, Plovdiv Branch (BG)
  • Bano Stefanov Faculty of Mechanical Engineering,Technical University of Sofia, Plovdiv Branch (BG)



pure/actual/finish milling, complex surfaces, CNC machine tool, optimization


The idle running times of the working units of a machine tool are the sum of the idle running times for the tool change and for changing the section uder treatment. The time, spent on idle running is the extra machining time. A large number of milling cutters are used for purely mechanical machining of details with complex surfaces and for a significant number of machined sections, where the complex surface is broken as a rule. This leads to an increase in the extra time for treatment. Reducing the auxiliary time in machining the parts will significantly increase the productivity of the actual milling process. When modeling the process of machining details with complex surfaces on triaxial milling machines, the optimization of the sequence of moves will allow to reduce the idle running time by up to 50% without causing deterioration in the quality of the surface layer.

Supporting Agencies
The results were obtained under a project funded by the research grant at TU –Sofia -contract № 222ПД0021-24 – Optimization of the parameters of technological processes for mechanical machining on CNC machines by means of digital models.


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B. Ponomarev, Optimization of the milling strategy. Irkutsk: IRSTU, 2003.

B. Ponmarev and B. Medvedev, “Optimization of the boundaries of honeycomb milling of parts with a complex profile and artistic bas-reliefs”, Scientific and Technical Conference on Improving the efficiency of technological preparation of machine-building production, November 15 -18 2002, Irkutsk, 2002.

B. Ponomarev and V. Repin, A method for automatically finding the optimal parameters for strategies for fine milling of complex parts, All-Russian Scientific and Technical Conference on Computer Technologies in Science, Design and Production, January 1999, Nizhny Novgorod, Russia. State Technical University, 1999.

B. Ponomarev and V. Repin, “Improving the productivity of shaping complex parts on CNC milling machines”, Journal of ISTU, vol.3, pp 50-53, 1998.

V. Danilov, Form-forming processing of complex surfaces by cutting. Minsk: Publishing House Nauka and Tekhnika,1995.

A. Groshev. “Methods and means of improving the accuracy of processing shaped parts on CNC milling machines”, M.S. thesis, Naberezhnochelni State University, Nabarezhnye Chelny, Russia, 2002.

A. Hanta, R. Grive and P. Broomhead, “Automatic CNC milling of pockets: geometric and technological issues”, Journal Computer Integrated Manufacturing Systems, vol.11, pp.309-330, 1998.

A. Makarov, „Optimization of the processing of complex-shaped parts on CNC milling machines“, M.S. thesis, Lomonosov Moscou State University, Moscow, Russia, 2002.

C. Zhu, “Tool-path generation in manufacturing sculptured surfaces with a cylindrical end – milling cutter”, Journal Computer in Industry, vol.7, pp.385-389, 1991.

F. Medvedev, “Creation of artistic bas-reliefs in the ArtCAM Pro software package”, Scientific and Technical Conference on Modern high-performance technologies in mechanical engineering for various industries, October 6-8 2001, Irkutsk, 2001.

G. Elber and E. Cohen, “Tool path generation for freeform surface models”, Journal Computer – Aided Design, vol. 26, pp. 490-496, 1994.

G. Sun, F. Wang and P. Wright, Operation Decomposition for Freeform Surface Features in Process Planning, ASME Design Engineering Technical Conference, September 12–16 1999, Las Vegas, Nevada, 1999.

H. Pottmann, J. Wallner and G. Glaeser, “Geometric criteria for gouge-free three-axis milling of sculptured surfaces”, Journal ASME of Mechanical Design, June 1999, Issue 121, pp.241-248, 1999.

S. Radzevich, Shaping the surfaces of parts. Kiev: Rastan, 2001.

S. Radzevich, Formation of complex surfaces on CNC machines. Minsk: Vysha Shkola, 1991.

V. Repin, „Method for automatic selection of a strategy for finishing complex-shaped parts on a three-axis CNC milling machine“, Journal of ISTU, vol.3, pp. 54-59, 1998.

Y. Lee and T. Chang, “Application of computational geometry in optimization 2.5D and 3D NC surface machining”, Journal Computers in Industry, vol.26, pp.41-59, 1995.

Y. Xiao, Z. Jiang, Q. Gu, W. Yan and R. Wang,”A novel approach to CNC machining center processing parameters optimization considering energy-saving and low-cost, Journal of Manufacturing Systems, Volume 59, Pages 535-548, April 2021.

A. Gromashev, B. B. Ponomarev and F.V. Medvedev, Vocational training of graduates of technical universities in the field of automation of design and technological work, International scientific and technical conference Mechanical engineering and the technosphere at the turn of the XXI century, Junе 2001, Doneck, Russia, 2001.

S. Salapateva, B. Stefanov, I. Chetrokov, “Mathematical model for minimizing a tool idle motion while milling complex surfaces on on 3-axis CNC milling machines when changing the machined area”, presented at National Conference on Mechanical Engineering and Mechanical Science (It is to be published in the journal Machine Science, 2023), Varna, Bulgaria, 2022.

C. Cerrone, R. Cerulli and B. Golden, “Carousel greedy: A generalized greedy algorithm with applications in optimization”, Computers & Operations Research, Volume 85, pp. 97-112, 2017,

J. Li, Y. Du, K. Gao, P. Duan, D. Gong and Q. Pan, “A Hybrid Iterated Greedy Algorithm for a Crane Transportation Flexible Job Shop Problem”, IEEE Transactions on Automation Science and Engineering, Volume 19, Issue: 3, pp. 2153-2170, 2022.

J. Dubois-Lacoste, F. Pagnozzi and T. Stützle, “An iterated greedy algorithm with optimization of partial solutions for the makespan permutation flowshop problem”, Computers & Operations Research, Vol.81, pp. 160-166, May 2017.

A. Brum, R. Ruiz and M. Ritt, “Automatic generation of iterated greedy algorithms for the non-permutation flow shop scheduling problem with total completion time minimization”, Computers & Industrial Engineering, Volume 163,107843, January 2022,

X. Han, Y. Han, B. Zhang, H. Qin, J. Li, Y. Liu and D. Gong, “An effective iterative greedy algorithm for distributed blocking flowshop scheduling problem with balanced energy costs criterion”, Applied Soft Computing, Volume 129, 109502, November 2022.

. J. Gallego, J. R. Rico-Juan and J. J. Valero-Mas, “Efficient k-nearest neighbor search based on clustering and adaptive k-values”, Pattern Recognition, Volume 122, 108356, February 2022,

L. Ribeiro de Abreu, K. A. Araújo, B. de Athayde Prata, M. S. Nagano and J. V. Moccellin, “A new variable neighbourhood search with a constraint programming search strategy for the open shop scheduling problem with operation repetitions”, Engineering Optimization, Volume 54, pp.1563-1582, 2022.

C.Friedrich and R. Elbert, “Adaptive large neighborhood search for vehicle routing problems with transshipment facilities arising in city logistics”, Computers & Operations Research, Volume 137, 105491, January 2022.

M. Alinaghian, M. Jamshidian and E. B. Tirkolaee, “The time-dependent multi-depot fleet size and mix green vehicle routing problem: improved adaptive large neighbourhood search”, A Journal of Mathematical Programming and Operations Research, Volume 71, 2022 - Issue 11: Special Issue Dedicated to the International Conference «Dynamical Control and Optimization», DCO 2021.

C. Zhang, F. Han and W. Zhang, “A cutting sequence optimization method based on tabu search algorithm for complex parts machining”, Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, Volume 233, Issue, 2018.




How to Cite

S. Salapateva, I. Chetrokov, and B. Stefanov, “ALGORITHM FOR OPTIMIZATION OF IDLE TOOL MOVES WHEN MILLING COMPLEX SURFACES ON A TRIAXIAL CNC MILLING MACHINE”, ETR, vol. 3, pp. 226–232, Jan. 2024, doi: 10.17770/etr2023vol3.7193.