Open-Source Hardware Design and Construction of a Modular Robotics Kit for STEM Education

This article presents the open-source hardware design, construction, and validation of a modular experimentation kit aimed at teaching robotics and automation concepts in secondary education. Addressing the limitations of expensive, proprietary educational tools, this work details the engineering of a replicable, low-cost platform based on the Arduino ecosystem and 3D-printed structural components. The kit comprises six distinct functional modules, ranging from basic environmental sensing to complex electromechanical automation, integrated with standard sensors (IR, RFID, DHT11) and actuators. The paper provides a comprehensive description of the hardware architecture, including mechanical CAD models, electronic schematics, and assembly instructions, ensuring full replicability by the open-source community. Validation was conducted through functional stress testing during a 6-hour workshop with 40 students, confirming the system's robustness and operational reliability. Furthermore, the pedagogical effectiveness of the hardware was assessed using a pre-test/post-test methodology ($p=0.01411$), demonstrating that this open-source design effectively bridges the gap between theoretical engineering concepts and practical application. All design files are provided as supplementary materials.