This paper presents the development of a low-cost, cyber-physical inventory management system, serving as Volume I of a multi-stage research project. The study focuses on the foundational prototype development and baseline system feasibility of utilizing sensor fusion and digital twin technology for MSME logistics. Initial iterations using standalone piezoelectric sensors identified a critical failure mode involving signal decay under static loads. To mitigate false detection and establish a reliable data foundation, a secondary LDR (Light Dependent Resistor)-based verification layer was integrated into a NodeMCU-based architecture. The framework is validated through a modular benchtop experimental setup synchronized with a 3D digital twin interface. While this phase establishes high-integrity data mirroring, a hypothesis for future optimization using 12-bit ADC platforms and predictive modeling is proposed as Volume II of this research.