ALGORITHMS FOR SOFTWARE COMPENSATION OF TORSIONAL VIBRATIONS IN H-BOT 3D PRINTERS BASED ON FILTERED B-SPLINES

The rapid development of additive manufacturing technologies imposes increasingly stringent requirements on the positioning accuracy and dynamic stability of motion systems, particularly in printers employing H-bot kinematic architectures, which are prone to torsional vibrations. Such vibrations significantly degrade print quality by inducing trajectory deviations of the print head and cannot be effectively mitigated solely through mechanical reinforcement or conventional control strategies. This study proposes a software-based torsional vibration compensation method founded on the use of filtered B-splines for motion trajectory correction at the planning stage. Unlike existing approaches that rely on rigid digital filtering or realtime adaptive control, the proposed method combines the high approximation capability of B-splines with selective attenuation of spectral components responsible for resonant torsional oscillations.
A mathematical model of torsional vibrations in H-bot frame structures is developed, followed by a spectral analysis of their dynamic characteristics to justify the applicability of B-spline-based filtering for identifying and compensating critical frequency components. Numerical simulation results demonstrate a substantial reduction in vibration amplitude and a corresponding decrease in trajectory tracking error of the print head. The practical relevance of the proposed approach lies in its ability to be integrated into standard trajectory planning algorithms without hardware modification, making it applicable to a wide class of H-botbased additive manufacturing systems.

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