4 Bar Linkage

4-Bar Linkage Mechanism

Project Overview

Designed and analyzed a planar 4-bar linkage mechanism (4R closed-loop system) to achieve a specified input–output motion relationship. The project focused on kinematic synthesis, motion analysis, and accurate representation of linkage behavior through both analytical and visual methods. The mechanism was modeled and simulated in Autodesk Fusion 360 and GeoGebra, with emphasis on developing precise IO relationships and understanding real-world applications of linkage systems.

How was the Project Created?

Performed analytical synthesis using both uniform and Chebyshev distributions of input–output angles, applying the tangent half-angle method to derive governing equations for the mechanism. Link dimensions were determined using coupler ratios, ensuring a unique and constrained design. Conducted detailed kinematic and dynamic analysis in Maple and MATLAB, including evaluation of angular velocity and acceleration under constant input conditions. Implemented continuous approximate synthesis (CAS) to minimize structural error across the motion range and compared results against uniform synthesis. Simulated and animated the mechanism in Fusion 360 and GeoGebra to validate motion and support intuitive understanding of linkage dynamics.

Results

Successfully developed and validated a functional 4-bar linkage design that meets the desired motion criteria with minimized structural error. Analytical and simulation results showed strong agreement, confirming the accuracy of the synthesized IO relationships and dynamic behavior. The project demonstrates a comprehensive approach to mechanism design, integrating kinematic synthesis, error evaluation, and mechanism simulation, while strengthening proficiency in engineering tools such as Maple, MATLAB, and CAD-based motion analysis.