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Key research themes
1. How are dynamic system modeling techniques advancing the analysis and control of vibration in mechanical and structural engineering?
This research theme focuses on analytical and numerical modeling methodologies for vibration behavior in mechanical systems and structures, aiming to improve prediction accuracy and applied control strategies. It encompasses mathematical modeling approaches ranging from classical continuous and discrete system representations to modern constrained and parameterization methods, supporting both theoretical insight and practical control implementation.
Key finding: This work consolidates comprehensive classical formulas for dynamic and vibration analysis of flexible systems, covering mass, stiffness, natural frequencies, mode shapes, damping, and dynamic response to time-dependent... Read more
Key finding: This study derives exact and approximate frequency equations for rods and beams carrying tip masses, comparing methods such as Rayleigh quotient, Dunkerley’s formula, and continuous system models. The findings reveal that... Read more
Key finding: This paper demonstrates that the cross-correlation function of ambient vibration responses approximates the system's impulse response, enabling time-domain curve-fitting techniques to estimate resonant frequencies, modal... Read more
Key finding: The authors present a scalable constrained dynamics model for space manipulators composed of rigid and flexible components, using quaternions for attitude representation to overcome Euler angle limitations. The approach... Read more
Key finding: This research develops an active vibration control framework for composite beams with electromagnetic actuators, employing a linear quadratic regulator designed via linear matrix inequalities. By formulating a multi-objective... Read more
2. What novel sensing and diagnostic methodologies enable early detection and quantification of mechanical vibrations and faults in engineering systems?
This theme captures research on innovative experimental techniques and data-driven methods for vibration monitoring, fault detection, and condition assessment in mechanical systems, emphasizing the extraction of vibration signatures and the development of predictive and robust diagnostic tools. The focus lies on real-time measurement approaches, vibration signal analysis, and machine learning applications, enhancing preventive maintenance and operational reliability.
Key finding: The study identifies Box-Jenkins type models for an electrostatic microgripper used for precise microparticle manipulation, based solely on operational data without expensive instrumentation. Robust linear low-order force... Read more
Key finding: This paper introduces a supervised machine learning model trained on measured vibration data from rotor faults under a fixed operating condition and evaluates its blind application to identical machines under varied... Read more
Key finding: By analyzing vibration signals measured at the hydrocyclone apex under varying feed slurry densities, the study identifies characteristic low-frequency shifts correlating with hydrocyclone choking onset. The vibration-based... Read more
Key finding: This experimental study quantifies vibration emissions of electric grinders during standard tests, validating a mechanical model that treats the grinder and unbalanced disk as coupled rigid bodies. It confirms that operator... Read more
Key finding: Through designed experiments varying cutting speed, feed, and depth, this study measures cutting tool vibration and surface roughness in hard turning, developing predictive regression and artificial neural network (ANN)... Read more
3. How do structural and environmental vibrations impact the safety and comfort of buildings, and which monitoring standards and mitigation strategies are effective?
This theme addresses the investigation of vibration exposure in structures due to anthropogenic and environmental sources, their influence on occupants' comfort and structural integrity, and the evaluation of differing national and international regulatory frameworks. Research includes vibration monitoring methodologies, assessment of vibrational loads from traffic and construction, and comparison of building responses to long-term versus impulse excitations, highlighting challenges in harmonized safety evaluation and control.
Key finding: This paper compares Polish and international codes for structural vibration monitoring and assesses their impact on structural safety evaluation. Case studies involving various excitation types reveal that differing standards... Read more
Key finding: By analyzing ground vibrations caused by both railway traffic and hammer impacts, this study demonstrates spectral and RMS acceleration/velocity comparisons showing similar vibration magnitudes but distinct temporal... Read more
Key finding: This work models the vertical vibration of two-axle vehicles coupled dynamically to a deformable road, incorporating wheel separation effects using contact state parameters in a seven-degree-of-freedom system. The coupled... Read more
Key finding: This paper compares vibration damping effects of buildings equipped with moving façades to those using tuned mass dampers (TMDs) under harmonic excitation. While both systems share similar dynamics, differing excitation... Read more