Recent Blogs
Chebyshev Approximate Straight-Line Linkage: Exact Four-Bar Closure
Quadrangular rectilinear motion explained — how a four-bar linkage produces straight-line output, with formulas, tolerances, and real packaging-line examples.
Power Escapement: One-Tooth Lock–Release–Relock Schedule
Power escapement explained — how it meters energy release in clocks, indexing tables, and ammunition feeds, with formulas, tolerances, and a worked example.
Positive Shuttle Motion: Valid Closed-Groove Cam Schedule
Positive Shuttle Motion drives a carriage back and forth with locked timing — how it works, formula, design tradeoffs, and named examples in textile and...
Pivoted Follower: Exact Declared Chord-Lift Geometry
Pivoted follower explained — how the swinging arm tracks a cam profile to drive valves, indexers and printing presses. Geometry, formula and worked example.
Bell-Crank Toe Levers: Declared Contact Layout
Explore two contacting bell-crank toe levers. Calculate combined reach, nominal overlap and output-tip arc lengths from pivot spacing, projection and swing.
Ovoid Curve: Declared Convex Limacon Geometry
Explore the convex limaçon r=R(1+e cos theta). Calculate minimum, maximum and selected-point radii and a polygonal approximation to its perimeter.
Ideal Simple Harmonic Motion: Circular Projection
Explore simple harmonic motion as a circular projection. Calculate ideal position, velocity, acceleration and phase from amplitude, angular frequency and time.
Oblique Rollers: Ideal Sheet-to-Guide Kinematics
Explore oblique rollers guiding sheet material toward a straight edge. Calculate ideal velocity components, lateral travel and the length needed to close a gap.
Oblique Disc Motion: Hiscox Rod-and-Roller Mechanism
Explore a tilted rotating disc driving a guided rod and roller. Calculate ideal stroke, peak rod speed and cycle period from radius, tilt and shaft...
Needle-Bar Slot Cam: Rotating Groove With Shuttle Dwell
Explore a needle-bar slot cam with an illustrative bottom dwell. Adjust stroke, dwell angle and shaft speed to calculate active angle and dwell duration.
Mutilated Rack Frame: Alternate Spur-Gear Rotation
Explore alternate spur-gear rotation from upper and lower rack runs on one moving frame. Calculate ideal rotation, pitch length and travel time.
Multiple-Return Grooved Cylinder: Travel and Cycle Calculator
Explore a grooved-cylinder traverse diagram and calculate follower travel, mean path speed, return cycles and reversal rate from stroke and drum speed.
Dual Crank-Wrist Spur-Gear Variable Traverse
Explore a dual crank-wrist spur-gear traverse and calculate opposite-direction speed ratio, crank-configuration repeat time and mesh tooth-passage rate.
Irregular Vibrating Circular Motion: Eccentric-Force Calculator | FIRGELLI
Calculate point-unbalance force and the net force from two equal vectors at a fixed phase difference. Machine vibration, force moments and structural response are not...
Irregular Cam Motion: Four-Phase Timing Calculator | FIRGELLI
Convert ordered cam-phase angles into rise, high-dwell, return and low-dwell times at constant speed. Includes an illustrative profile; roller contact and dimensional cam synthesis are...
Internal Rack Reciprocator: Pitch Speed and Nominal Rate Calculator | FIRGELLI
Calculate metric pinion pitch diameter, pitch-line speed and nominal traverse rates from an entered stroke. Tooth handoff and real cycle dynamics are not solved.
Internal Multiple Cam: Dimension and Phase-Time Comparisons | FIRGELLI
Explore a cam ring adjusting six radial slides. Separately compare diameter plus clearance and shaft phase time; these sums do not size the illustrated cam.
Intermittent Reciprocating Motion: Dwell Time Calculator | FIRGELLI
Convert a total dwell angle and constant input rpm into cycle, dwell and non-dwell time. Rack travel and gear engagement are illustrative.
Intermittent Rotary Motion: Geneva and Carousel Pitch Calculator | FIRGELLI
Compare external-Geneva output step, driver engagement and dwell with carousel station pitch. The calculator identifies a direct pitch match, not a complete mechanism design.
Hydro-Extractor: Basket-Wall Speed and Acceleration Calculator | FIRGELLI
Calculate ideal basket-wall rim speed, centripetal acceleration and acceleration relative to gravity from diameter and rpm. Extraction performance and safe operating speed are not calculated.
Hooke’s Angular Shaft Coupling: Ideal Speed Variation | FIRGELLI
Calculate the ideal minimum and maximum speed ratios of a single Hooke joint from shaft angle and input rpm. These kinematic results do not rate...
Heddle Cam: Dwell-Time and Frame-Travel Calculator | FIRGELLI
Explore camshaft dwell time, assumed heddle-frame travel and a simplified rise-dwell-fall cycle. Actual loom clearance and operating speed are not calculated.
Heart-Shaped Drum Groove: Ideal Traverse Calculator | FIRGELLI
Compare ideal axial traverse speed, unwrapped lead angle, half-turn timing and entered pin-to-groove width difference.
Grooved Cylinder Cam: Ideal Rise Calculator | FIRGELLI
Compare pressure angle, average rise speed and ideal torque for a constant-slope cylinder cam. Includes a rotating drum, guided follower, worked example and clear model...
Globe Gyroscope Mechanism: How It Works, Parts, Precession Diagram & Calculator
How a Globe Gyroscope works, why museums and physics labs rely on it for stable rotation demos, plus formulas, real specs and a worked spin-up...