Rapid urbanization coupled with a sharp surge in vehicle ownership has created acute parking crises inmetropolitanregions, especially in developing nations like India. Cities such as Pune, Mumbai, Bengaluru, and Delhi witness consistent vehiclegrowth, with Pune RTO recording over 3.03 lakh new registrations in 2024 (3.47% growth) and approximately 3.30lakhin2025(9% increase), including more than 2.11 lakh two-wheelers and 74,814 cars. Two-wheelers continue to dominate, contributingaround 60% of registrations, far outstripping available parking infrastructure and leading to chaotic on-street parkingthatoccupies 40% or more of road networks in core areas. This results in severe traffic congestion, excessive fuel wastage, elevatedairpollution levels (with idling vehicles contributing up to 30–40% of peak-hour emissions), driver frustration, andsubstantialeconomic losses estimated in billions annually. This paper details the end-to-end design, simulation, hardware prototyping, and performance validation of a microcontroller-basedAutomated Parking System (APS). The system features a multi-level grid-based mechanical structure governed by ahierarchicalnetwork of microcontrollers. A central Main Control Unit (MCU) orchestrates intelligent slot allocation and systemdiagnostics,while distributed Grid Control Units (GCUs) manage local actuation and sensing. Robust hybrid communicationis achievedthrough CAN for deterministic real-time control, SPI and I2C for high-speed local peripherals, and Modbus RTUforreliablemonitoring and SCADA integration. Innovative elements include multi-sensor fusion for accurate vehicle detection and positioning, closed-loop motor control withPIDtuning for precise platform movement, multi-layer interlocking safety mechanisms, and a user-centric Graphical User Interface(GUI) for real-time status visualization, logging, and manual intervention. The modular, scalable architecture accommodates deployments from small-scale residential setups (20–50 slots) to large smart-city installations (500+ slots), withspecialconsideration for mixed two-wheeler and four-wheeler parking common in Indian cities. Comprehensive simulations in Proteus and MATLAB/Simulink, alongside scaled hardware testing (1:8 prototype with3D-printedcomponents), demonstrate 82–88% space utilization, 70–85% reduction in average retrieval time (45–90 seconds), near-zerocollision rates, and robust fault tolerance (95% recovery within 2 seconds). Detailed power consumption analysis (180–280Wpercycle) and economic feasibility studies further establish practicality. By integrating cost-effective embedded solutions with industrial-grade protocols and safety engineering, this work addresses key gaps in existing literature. Future enhancements with renewable energy, AI-driven prediction, and IoT/cloud analytics align seamlessly with India’s Smart Cities Mission and sustainable urban development goals. Keywords: Automated Parking System, Microcontroller, STM32, Smart Parking, IoT, Smart City, Embedded Systems, CANProtocol, Multi-level Parking, Intelligent Control, Modbus, PID Control