Recent Blogs
Mutilated Bevel Gear: Opposed Intermittent Outputs A and B
Explore Brown movement 74: one toothed sector alternately drives two opposed bevel gears. Calculate ideal output steps, engagement sectors and dwell angles.
Maltese Cross Mechanism: Exact External-Geneva Timing
Explore an external Geneva mechanism. Calculate output step, driver indexing angle and dwell time from slot count and constant driver speed.
Silent Ratchet (friction) Mechanism Explained: How It Works, Diagram, Parts, Formula and Uses
Silent Ratchet (friction) explained — how friction-grip pawls index loads without clicking, with worked examples from elevator hoists and rod-feed lathes.
Combination Crank-motion Curves: Crank-Rocker Linkage and Interactive Pen Trace
Explore the curve drawn by a pen on a crank-rocker’s rigid connecting arm. Change link lengths, pen offset, starting angle and cycle time.
Sun and Planet Gear Mechanism Explained: How Watt's Epicyclic Drive Works, Parts, Diagram, Uses
Explore the sun-and-planet gear. Compare tooth counts, speed ratio and pitch geometry; equal gears give two sun revolutions per orbit in the ideal model.
Spiral-Stud Conical Wheel: Variable-Speed Motion, Diagram and Calculator
Explore opposed conical wheels on parallel shafts. Animate one spiral-stud pass and calculate local speed ratio, stud spacing and pass time.
Double Tri-toothed Pendulum Escapement Mechanism: How It Works, Parts, Geometry & Uses Explained
Explore the double tri-toothed pendulum escapement with alternating locks, a triangular arbor and curved pallets. Calculate release timing and tip motion.
Elastic Spur Gear Mechanism Explained: How It Works, Diagram, Parts, Formula and Uses
See a toothed rim wind against a spring-coupled shaft center. Calculate relative angle, stored energy, arc displacement and tangential force from supplied stiffness.
Combination of Friction Gear Mechanism: How It Works, Diagram, Parts, Formula, and Uses Explained
Compare three friction-wheel diameters and their ideal speed ratios. See why the idler changes its own speed and shaft spacing while the final ratio stays...
Wittgenstein's Rod: Clearance and RSS Error-budget Calculator
Compare entered rod clearance, pin play and straightness with an assumed root-sum-square budget. The tool does not solve linkage motion or production tolerances.
Watt Six-bar Linkage: Mobility Count and Dwell-time Comparison
View a fixed illustrative Watt I six-bar. Calculate generic planar mobility and convert an entered interval to cycle angle and percentage at constant speed.
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.
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.
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.
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.
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.
Parallel Ruler (Form 5): Hiscox Slotted Crossed Bars
Explore Hiscox’s slotted parallel ruler with equal crossed bars. Calculate ruler separation, sliding-end span and center-to-end distance from bar length and angle.
Parallel Ruler (Form 1): Exact Equal-Arm Translation
Explore an equal-arm parallel ruler. Calculate longitudinal shift, line separation, enclosed area and ideal parallelism from pivot spacing, arm length and angle.
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.
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.
Crossed-slider Chain Mechanism Explained: How It Works, Parts, Formula, and Uses
Explore an elliptic trammel with a tracing point between two slider pins. Calculate ellipse width, height, area and pin spacing, and compare slider travel.