Recent Blogs
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.
Three-link Kinematic Chain: Generic Planar Mobility
Compare open and closed ideal three-link chains, counting ground as one link. Calculate nominal mobility and joint constraints without solving dimensions or motion.
Ten-bar Linkage: Nominal Planar Mobility Calculator
Explore a conceptual ten-link chain and calculate its nominal planar mobility from link and revolute-joint counts. Dimensions and motion paths are not solved.
Sylvester–Kempe Linkage: Concept and Illustrative Budget
Explore the historical straight-line linkage concept and a separate illustrative mismatch-and-clearance budget. The arithmetic does not predict tracer error.
Swashplate Mechanism: How a Helicopter Rotor Head Works, Parts, Diagram and Uses Explained
See how collective and cyclic controls affect a helicopter swashplate. Explore ideal attachment height and frequency; blade pitch and loads are not calculated.
Studded Disk and Bell Crank: Alternating Motion Calculator | FIRGELLI
Explore a studded disk driving a bell crank with a weighted-cord return. Calculate event timing, ideal cord tension and counterweight moment.
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.
Stephenson Topology Six-bar Linkage: How It Works, Diagram, Parts, Uses & Calculator
Stephenson topology six-bar linkage explained — how it works, kinematic equations, and real applications in packaging, automotive seats, and industrial machines.
Steering Linkage Mechanism Explained: Ackermann Geometry, Parts, Diagram and Calculator
How a Steering Linkage works, with Ackermann geometry, tie rod sizing, bump steer math, and a worked example for an off-road truck build. Engineer's guide.
Slider Crank Chain Inversion Mechanism: How It Works, Diagram, Parts and Uses Explained
Explore a crank-driven slotted lever and connected ram, and compare ideal long and short stroke times from crank radius, pivot spacing and speed.
Six-bar Linkage Mechanism Explained: How It Works, Parts, Diagram and Uses
Explore a moving Watt-type six-bar linkage with seven pin joints and use the planar mobility calculator to compare link and joint counts.
Single Pivoted Clamp with Fixed Side-piece: How the Lever Mechanism Works, Parts & Uses
Explore a curved pivoted clamp jaw and fixed side piece, then compare ideal lever forces with selected arm lengths and a loss percentage.
See-saw Mechanism Explained: How a First-Class Lever Balances Torque, Parts, and Uses
How a see-saw lever works, the pivot geometry that makes it balance, and real-world examples from playgrounds to industrial counterweighted lifts.
Screw-clamp (handle and Lever Holder) Mechanism Explained: How It Works, Parts, Formula and Uses
How a screw-clamp handle and lever holder works, the clamping force formula, and real-world examples from machine shops, jig builders, and fixture designers.
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.
Rod End Bearing Mechanism: How It Works, Parts, Diagram, and Linkage Uses Explained
Rod End Bearings (Heim joints) handle misalignment in linkages — see how they work, load ratings, failure modes, and selection rules for motorsport and CNC...
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.
Rigid Origami Mechanism Explained: How Single-DOF Miura-ori Folding Works, Parts, Formula & Uses
Rigid origami folds flat panels along hinge creases without bending the faces. Used in aerospace deployables, medical stents, and architectural shading systems.
Rhombic Drive Mechanism: How Philips' Counter-Rotating Stirling Linkage Works, Diagram & Uses
Explore a symmetric rhombic drive with counter-rotating cranks and four equal links. Calculate rhombus height limits and shaft angular speed.
Quadruplanar Inversor: Ideal Circle-Inversion Map
Quadruplanar Inversor explained — how this 4-bar inversion linkage converts circular motion to straight-line travel for drafting tools, optics jigs, and lab gear.
Quadrant Catch Hand-Gear Form B: Ideal Reduction Ledger
Quadrant catch hand-gear form B explained — how the spring-loaded pawl locks elevation arcs on field guns and survey theodolites, with formulas and a worked...
Quadrant Catch Hand-Gear Form A: Declared Arc-Index Ledger
Quadrant Catch Hand-gear Form A explained — how the toothed quadrant lever locks naval gun elevation, with diagrams, formulas and restoration examples.
Two-Oblique-Bar Press Motion: Exact Toggle Geometry
Two oblique bars convert horizontal input into vertical press motion. See the geometry, formula, worked example, and trade-offs for press tooling builders.
Single-Rod Hydraulic Cylinder: Ideal Net Rod Load and Nominal Stress
Piston Rod explained — how it transmits force from piston to crank, sizing rules, buckling limits, and real examples from diesel engines to hydraulic presses.
Peaucellier-Lipkin Linkage: Exact Straight-Line Inversor
Explore the Peaucellier-Lipkin straight-line linkage. Calculate the inversion constant, line offset and ideal output stroke from link lengths and driver swing.