Validus Group Inc.  |  Technical Library

Validus Group Technical Library

Engineering · Automation · Precision Manufacturing · Applied AI & Operations

This library contains engineering papers, technical documentation, and reference material developed by Validus Group for advanced manufacturing, controls, automation integration, sensor-driven systems, and practical operations execution. Each entry can be opened directly in the browser or printed on standard 8.5" × 11" paper.

Sensors & Embedded Systems

Interfacing, bus discovery, validation workflows

Jetson Orin Nano: I²C + ADXL345 Integration White Paper

Hardware interface overview, I²C bus discovery, timing and addressing, ADXL345 register configuration, and a practical test workflow for stable sensor acquisition on Jetson Orin Nano.

Tags: Jetson Orin Nano · ADXL345 · I²C · Embedded Linux · Sensor Integration

Controls, PLCs & Motion Systems

Safety architecture, motion profiles, practical controls

Rotary Molding: Dynamic Load & Process Stability Analysis

Analysis and control strategy for rotary molding operations, including cycle optimization, servo-based motion profiling, and downtime reduction tactics in production environments.

Tags: Rotary Molding · Motion Control · Servo Systems · Cycle Optimization

Two-Hand vs. Light Curtain Safety Relay: Practical Controls Comparison

Comparison of dual two-hand control and light curtain-based safety implementations for presses and motion systems, including relay selection, risk considerations, and practical wiring concepts.

Tags: Safety Relays · Two-Hand Control · Light Curtains · Machine Safety · Press Controls

Raspberry Pi + Relay DDL: PLC Input Simulation & Fault Injection via I²C

Low-cost, repeatable PLC input simulation using a Raspberry Pi 4 and a 4-channel Relay DDL I²C HAT. Includes I²C enablement, venv setup, bus scan validation at 0x10, and deterministic seeded stimulus patterns for fault injection and regression testing.

Tags: Raspberry Pi · Relay DDL · I²C · PLC Inputs · Fault Injection · Regression Testing · Commissioning

Raspberry Pi 4 + Waveshare 8-Channel GPIO: Deterministic Output Control (Debian Trixie)

Field-proven GPIO control method for 8-channel Waveshare boards on Raspberry Pi 4 running Debian Trixie headless. Includes confirmed CH1–CH8 pin mapping, gpiod v2 notes, permissions/udev rules, venv setup, and a gpioset “holder process” pattern to prevent floating lines and “stuck” outputs.

Tags: Raspberry Pi 4 · Waveshare 8-Channel · GPIO · gpiod v2 · Debian Trixie · Headless · Automation Integration

Magnetic Fields Refresher (Engineering): E, H, B, Materials, and Practical Design

An engineering-level refresher that connects Maxwell’s equations and constitutive laws to practical design work (cores, gaps, inductors/transformers, saturation, and loss mechanisms including eddy currents and skin depth).

Tags: Electromagnetics · Magnetic Fields · E/H/B · Inductors · Transformers · Motors · Materials · Saturation · Eddy Currents

Contactor Coil Snubbers (AC/DC, 220 VAC): Practical Selection & Wiring Tech Note

A practical field note on coil suppression for contactors and relays: why snubbers matter (PLC output protection, EMI control, nuisance-trip reduction, contact life), how AC vs. DC coils differ, and when to use RC snubbers, MOVs, diodes, or TVS devices. Includes wiring placement guidance and common failure modes to avoid.

Tags: Contactor Coils · Snubbers · RC · MOV · Flyback Diode · TVS · EMI/EMC · PLC Outputs · 220 VAC

Dual Check Valves on Air Cylinders: Preventing Lockup, Drift, and Unstable Motion (Tech Note)

Why air cylinders can lock-up, “ratchet,” or behave unpredictably when flow paths backfeed or pressure equalizes across ports. Covers the practical purpose of dual check valves (and where they belong), how they stabilize motion and holding behavior, and best-practice design guidelines to avoid common pneumatic failure modes.

Tags: Pneumatics · Air Cylinders · Dual Check Valves · Motion Stability · Lockup Prevention · Best Practices

Operations & Workforce Capability

Hiring signal quality, capability validation, loss reduction

Credential Chasing and the “Online Degree Signal” Problem

How low-signal credentials, weak validation, and checkbox hiring quietly increase cost, risk, and operational drag — and a practical capability-first framework to fix it.

Tags: Hiring Signal Quality · Operational Loss Reduction · Capability-First Screening · Promotions · Risk & Reliability

Software Engineering & Dev Tooling

Python packaging, editable installs, unit test discovery

Python Project Layout: src/, Editable Installs, and Reliable unittest Discovery

Practical guidance for structuring Python repos with a src/ layout, using editable installs for clean local development, and making unittest discovery behave consistently across CLI runs, IDEs, and CI. Covers common failure modes and a repeatable workflow that prevents “it works on my machine” regressions.

Tags: Python · src Layout · Editable Install · pip · Packaging · unittest · Test Discovery · Repo Structure · CI

CNC, Tooling & Process Optimization

Probing, process windows, chatter mitigation, 5-axis tuning

Future location for CNC process capability notes, fixturing concepts, and optimization white papers. Topics will include probing strategies, tooling selection, chatter mitigation, and 5-axis process tuning.

Data, Analytics & Predictive Systems

Measurement → insight → sustained standards

Tribal Knowledge, Cross-Functional Collaboration, and Hidden Manufacturing Losses

A quantitative framework for estimating the annual financial impact of person-dependent processes across performance, quality, downtime, and training, and how weak Production–Engineering–Maintenance collaboration amplifies those losses.

Tags: Tribal Knowledge · OEE & Capacity · Continuous Improvement · Cross-Functional Teams · Manufacturing Operations

Probabilistic Root Cause Assessment (PRCA): A Practical Engineering Framework

A structured, probability-based approach to troubleshooting complex equipment and manufacturing problems. Covers hypothesis framing, evidence weighting, confidence updates, and how to avoid common failure modes like “single-cause fixation” and low-signal assumptions.

Tags: Root Cause · Troubleshooting · Probabilistic Reasoning · Bayesian Updating · Reliability · Manufacturing Operations

Future additions in this section will cover vibration/FFT workflows, accelerometer-based condition monitoring, and practical AI/ML approaches for predictive maintenance and defect classification.