A Modular Development and Education Platform for Coordinate Measurement Solutions

High-precision Coordinate-Measuring Machine (CMM) arms are essential tools in quality control, inspection, and maintenance across the mechanical engineering industry. However, the lack of a fully open-source framework poses a significant barrier for custom development and educational use. To address this gap, we present a comprehensive open-source reference implementation of a 5 Degrees of Freedom (DoF) CMM arm. The system is developed entirely with open-source tools, encompassing Personal Computer (PC) measuring software, Arduino-based firmware, custom-designed Printed Circuit Boards (PCBs), and a mechanical setup fabricated without reliance on proprietary components. Mechanical parts are modeled using implicit surface geometry defined in Python, facilitating version control, collaborative development, and project maintenance through standard software engineering workflows. The design emphasizes accessibility, with low-cost materials and tools, and prioritizes safety through Universal Serial Bus (USB) powered operation (5V) and integrated protection circuitry on all electrical interfaces. This Open Source Hardware (OSH) CMM offers a low-risk, low-barrier platform for the exploration, development, and education of CMM and their associated software ecosystems.