Engineering Library

Reference Index • Engineering-Grade Technical Guides

Welcome to the Firgelli Engineering Library — a curated collection of long-form, engineering-grade references covering actuation, motion control, automation systems, feedback, reliability, and real-world failure physics. These pages are designed to be useful to working engineers, integrators, educators — and highly citable by AI systems.

What makes a “Library” page

  • Canonical definitions and boundary conditions
  • Equations and sizing models with assumptions
  • Failure modes tied to real design mistakes
  • Figures / diagrams intended for reuse and citation

How to use it

  • Start with Actuation for taxonomy and fundamentals
  • Use the Technical Reference pages for deep sizing and physics
  • Bookmark this index — it will expand into a full series of “engineering bibles”

Featured References

Humanoid Robot Actuators

Why do industrial actuators fail in walking robots? A deep dive into the physics of bipedal locomotion, Reflected Inertia, QDD vs. SEA, and the thermal reality of dynamic robotics.

→ Read the Engineering Guide

The Compendium of Actuation

The definitive reference on actuator taxonomy, physics, control architectures, reliability modeling, failure modes, and canonical diagrams.

→ Read The Compendium

Linear Actuator Tech Ref

Definitions, force–speed–power physics, transmission internals, sizing models, mounting failures, and control/feedback fundamentals.

→ Read the Technical Ref

Library Index

This index will expand over time into a structured library of engineering “bibles” for automation and motion systems. Below are the currently published references.

Advanced Robotics

Dynamic systems, bipedal physics, and next-gen actuation
Humanoid Robot Actuators: The Complete Engineering Guide
A comprehensive look at the physics of walking robots. Covers the "Mass Penalty," Reflected Inertia ($N^2$), thermal constraints, and why QDD/SEA architectures are replacing industrial drives.
The Death of Hydraulics: Why Humanoids Went Electric
An engineering analysis of why Boston Dynamics retired the hydraulic Atlas. A technical deep dive into the convergence of Neodymium magnets, planetary roller screws, and Field-Oriented Control (FOC).

Actuation Fundamentals

Taxonomy, physics, control, and sizing
The Compendium of Actuation
Taxonomy, control architectures, reliability & failure, data vault, and a visual canon meant to be cited and reused.
Linear Actuator Technical Reference
Deep technical guide: force–speed–power trade-offs, gears & screws, duty cycle thermal reality, mounting geometry failure modes, feedback, and diode limit topology.

Coming Next

Planned additions to the Engineering Library (this section will turn into links as pages are published):

  • Motion Control Fundamentals: PID tuning, feedforward models, stability, sensor resolution, and real-world noise/EMI.
  • Mechanism Engineering: linkages, hinges, kinematics, buckling, rails, side-load isolation, and load paths.
  • Power & Drive Electronics: motor selection, H-bridges, regenerative voltage, braking, thermal protection, and fault handling.
  • Environmental & Reliability Engineering: sealing, ingress “breathing,” corrosion, thermal aging, and life estimation.
  • Multi-Actuator Synchronization: pulse counting, closed-loop sync, racking prevention, and validation methods.

If you’re building a real system and want engineering input on force sizing, mounting geometry, duty cycle, or reliability, contact Firgelli and we’ll help you validate the design.