Recent Blogs
Crank and Slotted Lever: Sweep-Time Calculator | FIRGELLI
Calculate slotted-lever sweep angles, unequal timing intervals and cycle time from crank radius, center distance and speed. The attached ram has separate turning points.
Hoecken Linkage: Link-Length Scaling and Model Limits | FIRGELLI
Explore approximate straight-line linkage geometry and calculate scaled link lengths. Velocity variation, usable stroke, full-cycle closure and payload are not verified by this tool.
Grashof Linkage: Four-Bar Assembly and Rotation Calculator | FIRGELLI
Check four link lengths for assembly and Grashof rotation. Compare sorted sums and margin, with a longest-ground four-bar animation and worked example.
Closed Four-Link Chain: Planar Mobility Calculator | FIRGELLI
Explore planar link and joint counts, the Gruebler–Kutzbach equation and a four-bar illustration. Understand connectivity and constraint assumptions.
Four-Bar Linkage: Grashof Margin and Geometry Explorer | FIRGELLI
Explore four-bar lengths, Grashof margin and sampled angles. Learn the limits of branch selection, angle spans and the illustrative index.
Evans Grasshopper Linkage: Coupler-Path Calculator | FIRGELLI
Explore an Evans four-bar linkage with an approximately straight coupler path. Compare link scale, crank sweep, traced stroke and lateral wander.
Drag-link Mechanism Explained: How It Works, Parts, Diagram, Quick-Return Uses & Formula
Explore a drag-link four-bar with adjustable link lengths and input speed. Calculate Grashof margin, variable output rpm and two output half-turn times.
Double-rocker Mechanism: How It Works, Parts, Formula, Diagram and Uses in Four-Bar Linkages
Explore a double-rocker four-bar linkage. Set four link lengths to calculate assembly class, feasible input limits and sampled output swing.
Double-crank Mechanism Explained: How It Works, Diagram, Parts, Grashof Condition and Uses
Explore a double-crank four-bar linkage. Adjust link lengths, check the Grashof condition, and calculate instantaneous output speed through the cycle.
Crank-rocker Mechanism: How It Works, Diagram, Parts, Formula, and Industrial Uses Explained
Explore four-bar linkage geometry. Check full input rotation, output angular range, Grashof margin and minimum transmission angle from four entered link lengths.
Cognate Linkage Mechanism: How It Works, Roberts-Chebyshev Theorem, Diagram and Uses Explained
Compare three Roberts–Chebyshev four-bar cognates tracing one point path. Scale the coupler triangle and inspect matching configurations and different fixed pivots.
Chebyshev Linkage: Double-Rocker Motion and Coupler-Midpoint Path
Explore a Chebyshev double-rocker linkage. Adjust four link lengths and compare sampled horizontal span and vertical variation of the coupler midpoint.
Rocking Motion Mechanism Explained: Crank-Rocker Four-Bar Linkage, Parts, Formula & Uses
Rocking motion converts continuous rotation into a bounded back-and-forth swing. Learn the geometry, formula, and real applications across textile, packaging, and HVAC.
Rocking Arm Mechanism Explained: How a Crank-Rocker Four-Bar Linkage Converts Rotation to Oscillation
Rocking Arm mechanism explained — how it converts rotation to oscillation, sizing formulas, real machine examples in textiles, printing, and packaging.
Drag-link Quick-return Mechanism: How It Works, Diagram, Parts, Time Ratio and Uses Explained
Explore a drag-link quick-return drive with a guided ram. Calculate stroke, position, velocity and the time ratio between its two travel directions.