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Hard vs soft impacts in oscillatory systems' modeling revisited
Andrzej Okolewski1, Barbara Blazejczyk-Okolewska2
1Institute of Mathematics, Lodz University of Technology, Wolczanska 215, Poland.
Chaos (Woodbury, N.Y.)
|September 2, 2021
Summary
This study re-examines soft and hard impact models for vibro-impact systems. Different results arise when applying the soft impact model to systems with low stiffness or high energy dissipation compared to the hard impact model.
Area of Science:
- Mechanical Engineering
- Vibration Analysis
- Nonlinear Dynamics
Background:
- Vibro-impact systems are crucial in many engineering applications.
- Soft and hard impact models are commonly used to represent collisions within these systems.
- Understanding the equivalence and differences between these models is essential for accurate system representation.
Purpose of the Study:
- To reconsider the application of soft and hard impact models for vibro-impact systems.
- To discuss the conditions for equivalence between soft and hard impact models regarding energy dissipation.
- To investigate the influence of additional elastic-damping elements and external forcing on system behavior.
Main Methods:
- Revisiting and analyzing existing soft and hard impact models.
- Deriving and demonstrating key features of soft impact models.
- Examining the effects of system modifications (elastic-damping element, external forcing) on vibro-impact dynamics.
Main Results:
- Conditions for energy dissipation equivalence between soft and hard impact models were established.
- Soft impact models exhibit distinct behaviors compared to hard impact models under specific conditions.
- Discrepancies arise when the soft impact model is applied to low-stiffness bases or high-dissipation stiff bases.
Conclusions:
- The choice of impact model (soft vs. hard) significantly affects vibro-impact system behavior, particularly with variations in stiffness and energy dissipation.
- The soft impact model offers a more nuanced representation in scenarios with significant energy loss or flexible system components.
- Further research into model selection criteria for specific vibro-impact applications is warranted.
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