Features of a real-time s-shaped acceleration/deceleration curve constructing with piecewise linear interpolation of complex-shaped surfaces

Features of a real-time s-shaped acceleration/deceleration curve constructing with piecewise linear interpolation of complex-shaped surfaces

Alexander A. Zelensky
Federal State Educational Institution of Higher Education «Moscow State Technological University «STANKIN» (FGBOU VO «MST «STANKIN»), Department of High Performance Technologies and Processing, Assistant Professor, 1, Vadkovsky per., Moscow, GSP-4, 127055, Russia, This email address is being protected from spambots. You need JavaScript enabled to view it.

Tagir Kh. Abdullin
FGBOU VO «MST «STANKIN», laboratory of Electronic Modules Production Technologies, Leading Engineer, 1, Vadkovsky per., Moscow, GSP-4, 127055, Russia, This email address is being protected from spambots. You need JavaScript enabled to view it.

Andrei V. Alepko
FGBOU VO «MST «STANKIN», laboratory of Electronic Modules Production Technologies, Leading Engineer, 1, Vadkovsky per., Moscow, GSP-4, 127055, Russia, This email address is being protected from spambots. You need JavaScript enabled to view it.

Received 08 June 2021

Abstract
In this paper we considered the problem of an s-shaped acceleration/deceleration curve constructing in real time with linear-spline interpolation, taking into account given constraints on the contour acceleration, jerk, and feed rate. The input data for the s-curve were defined in the lookahead algorithm and the geometric smoothing module. The choice of a particular acceleration/deceleration strategy depends on the segment length, the allowable feed rates at the segment junction, and the given kinematic constraints. Each trajectory segment can have a maximum of seven time intervals and their rounding will produce inaccuracies when forming the velocity profile. Therefore, to compensate for rounding errors, the method of half division was applied, which made it possible to remove gaps in the velocity contour. The experimental data obtained indicate the correctness of the chosen approach for its implementation as part of the CNC for high-speed machining of surfaces with complex shapes.

Key words
Feed-rate planning algorithm, s-shaped acceleration/deceleration, trajectory smoothing, numerical control system, real-time, frame preview algorithm.

Acknowledgements
The research was carried out with financial support of Ministry of Science and Higher Education of Russian Federation in the frame of state assignment (project no.FSFS-2020-0031).

DOI
https://doi.org/10.31776/RTCJ.9304

Bibliographic description
Zelensky, A., Abdullin, T. and Alepko, A., 2021. Features of a real-time s-shaped acceleration/deceleration curve constructing with piecewise linear interpolation of complex-shaped surfaces. Robotics and Technical Cybernetics, 9(3), pp.186-195.

UDC identifier:
519.688

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