Recent Blogs
Two-degree Cylindrical Pair: Independent Sliding and Rotation
Explore independent axial sliding and rotation in a cylindrical pair. Compare entered geometric ratios and a simple friction estimate; jamming is not predicted.
Spherical Pair Mechanism Explained: How a Ball-and-Socket Joint Works, Diagram, Parts, and Uses
Spherical pair explained — how a ball-and-socket joint delivers 3 rotational DOF with zero translation, with formulas, real robotics examples and tolerances.
Sliding-and-rotating Prism in Cylinder: How This Two-DOF Kinematic Pair Works, Parts, and Uses
Explore independent rotation and sliding of a hexagonal prism in a circular bore. Calculate its ideal corner envelope, section area and engagement ratio.
Roller-on-cam Higher Pair Mechanism: How It Works, Diagram, Pressure Angle and Uses Explained
Roller-on-cam higher pair explained — contact geometry, pressure angle, and sizing for automotive valvetrains, indexers, and packaging cams. With worked example.
Prismatic Pair: Declared Sliding-Friction Ledger
Prismatic Pair explained — the sliding lower-element joint behind every Linear Actuator, machine slide and hydraulic cylinder. Specs, formulas, real builds.
Planar Pair: Exact Three-Coordinate Pose Geometry
Planar Pair explained — the plane-on-plane kinematic pair gives 3 DOF in machine-tool slides, surface grinders, and flatbed printers. Formula, examples, tradeoffs.
Hyperboloid Pair: Ideal Effective-Radius Ratio Calculator | FIRGELLI
Compare ideal speed and torque ratios for two effective rolling radii. The tangent-circle illustration does not design hyperboloid surfaces, teeth or skew-axis contact.
Helical Gear Pair: Ideal Force-Component Calculator | FIRGELLI
Calculate tangential and axial force magnitudes from torque, pitch diameter and helix angle. Contact ratio is entered, and gear strength and bearing life are not...
Gear-Tooth Higher Pair: Involute Gear Geometry Calculator | FIRGELLI
Calculate nominal spur-gear ratio, driven speed, centre distance and pitch-line speed. Explore how pressure angle changes the base circles and line of action.
Cylindrical Pair (revolute) Mechanism Explained: How It Works, Diagram, and Uses
Explore a journal with axial retaining collars. Calculate projected bearing area, nominal radial pressure and length-to-diameter ratio from load and dimensions.
Cylinder-on-cylinder Lower Pair Mechanism: How It Works, Diagram, Parts and Uses Explained
Explore independent sliding and rotation in a cylindrical joint. Compare bore and shaft diameters to calculate signed radial and diametral clearance.
Cone-on-cone Rolling Pair Mechanism: How It Works, Parts, Formula and Uses Explained
Explore ideal rolling cones with a shared apex. Compare cone angles, shaft angle and speed ratio, with apex offset shown as a separate length comparison.
Cam-and-follower Higher Pair Mechanism: How It Works, Diagram, Parts, Formula and Uses Explained
Explore a harmonic disk cam and guided knife-edge follower. Compare lift, peak speed and pressure angle, with equations and a worked example matching the calculator.
Screw Pair Mechanism: How It Works, Diagram, Lead Formula, Parts, and Uses Explained
Screw Pair explained — how helical threads convert rotation into linear motion, with lead/pitch math, real applications in machining, and design tradeoffs.