Numerical and Dynamic Errors Analysis of Planar Multibody Mechanical Systems With Adjustable Clearance Joints Based...

Area of Science:

• Mechanical Engineering
• Dynamical Systems Analysis
• Computational Mechanics

Background:

• Accurate dynamical models are essential for multibody mechanical systems, especially those with clearance joints.
• Existing models often lack simplicity or accuracy for engineering applications.

Purpose of the Study:

• To present a novel, accurate, and simple dynamical modeling methodology for multibody mechanical systems with clearance joints.
• To validate the proposed methodology using a slider-crank mechanism.

Main Methods:

• Developed a new numerical methodology based on Lagrange equations of the first kind, treating clearance joint length and rotation angle as independent coordinates.
• Utilized a slider-crank mechanism with adjustable revolute clearance joints as the numerical model.
• Employed a test rig and Simulink model for experimental validation and compared results with numerical predictions.

Main Results:

• Numerical results closely matched experimental and Simulink data, confirming the methodology's correctness for modeling mechanisms with clearance joints.
• Lyapunov exponent analysis revealed the chaotic or periodic motion status of the slider.
• Mean Absolute Deviation (MAD) quantified dynamical errors (displacement, velocity, acceleration) caused by clearance joints.

Conclusions:

• The presented methodology offers a valid approach for deriving dynamical equations of mechanisms with clearance joints.
• Clearance size and drive speed significantly influence slider dynamics, exhibiting complex yet predictable behaviors.
• The study provides a robust framework for analyzing and predicting the performance of mechanical systems with joint clearances.