Recent Blogs
Watt's Linkage: Illustrated Path and Cubic Comparison
View the midpoint path of a fixed illustrative Watt four-bar. Compare an assumed cubic expression with an entered allowance; it is separate from the drawn...
Tusi Couple: Two-to-one Geometry and Straight-line Stroke
Explore the ideal straight-line trace of a circle rolling inside a circle twice its diameter. Calculate stroke and amplitude for the exact two-to-one case.
Hoeken Straight-Line Example: Animation and Path Calculator | FIRGELLI
Scale a defined Hoeken four-bar and compare travel, sampled deviation and crank period. See the approximately straight working interval and curved return.
Scott Russell Linkage Mechanism Explained: Diagram, Formula, Stroke and Uses
Scott Russell linkage explained — how this straight-line mechanism converts rotary motion into perfectly linear travel for test rigs, lifts, and lab equipment.
Roberts Linkage Mechanism: How It Works, Diagram, Formula, and Uses in Straight-Line Motion
Roberts Linkage explained — a four-bar straight-line mechanism used in robotics, prosthetics, and instrument design. Geometry, formulas, and a worked example.
Hart's Inversors: Crossed-Link Motion and Geometry Calculator
Explore a Hart inversor with a crossed four-link cell, circular input and straight tracing point. Calculate the midpoint inversion constant from full bar lengths.
Hart's Exact Straight-Line Inversor: Stroke and Animation
Size an ideal Hart inversor stroke from full bar lengths. See the crank angle, available travel and connected crossed-link motion without a sliding guide.
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.
Elliptical Crank: Trammel Animation and Point-Velocity Calculator
Explore a double-slider elliptical trammel. Adjust horizontal and vertical semi-axes, initial phase and cycle time while following position and speed.
Hart's W-frame: Crossed-Link Animation and Stroke Calculator
See a Hart W-frame maintain an ideal straight tracing path. Compare bar sizes, input swing and stroke with a connected crossed-link animation.
Rack-Gear Parallel Motion: Ideal Opposed-Rack Kinematics
Rack gear parallel motion guides a steam piston rod in a straight line using a rack, pinion and counter-rack. See the geometry, math and a...
Peaucellier Parallel Motion: Exact Inversion Straight Line
Explore the Peaucellier straight-line linkage. Calculate its inversion constant, line offset and ideal output stroke from link lengths and driver swing.