Assembly Line Interlock System with Feedback Using ESP8266
Keywords:
Assembly line interlock system, ESP8266 NodeMCU, IoT-based monitoring, Operator feedback, Poka-yoke, Token verificationAbstract
Modern manufacturing industries face several challenges, including assembly sequence errors, skipped operations, inconsistent product quality, and production delays caused by manual supervision and human intervention. These issues reduce manufacturing efficiency, increase product rejection rates, and affect overall production reliability. To address these challenges, this paper presents an Assembly Line Interlock System with Feedback using ESP8266 NodeMCU. The proposed system is designed to ensure proper sequential verification during assembly operations through an interlocking mechanism based on Poka-Yoke (mistake-proofing) principles. The system integrates ESP8266 NodeMCU as the central controller along with SG90 servo motors, relay modules, push-button feedback switches, an OLED display, and a web-based monitoring dashboard. During operation, each assembly stage is activated sequentially, and the operator must confirm completion of the current task before proceeding to the next stage. This confirmation-based interlocking mechanism prevents skipped operations and assembly sequence violations. The OLED display provides real-time instructions and status updates, while the relay module supports testing and process verification functions. Additionally, a token verification mechanism is implemented to improve product traceability and ensure that only verified products proceed to the final testing stage. The web-based dashboard enables real-time monitoring of assembly activities and production status. The developed system is low-cost, reliable, scalable, and suitable for smart manufacturing and industrial automation applications.
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