This paper presents the design and development of a portable, low-cost mechanical ventilator intended for emergency respiratory support in resource-constrained healthcare environments. The proposed system automates a conventional Bag Valve Mask (BVM) using a stepper motor– driven lead screw mechanism to deliver controlled ventilation. Key parameters such as tidal volume, respiratory rate, airway pressure, and inspiration–expiration ratio are regulated using a microcontroller-based control unit. Real-time feedback from an airway pressure sensor and a pulse oximeter ensures patient safety by preventing over-pressurization and maintaining                              adequate            oxygenation. Experimental evaluation using an artificial lung model demonstrates stable and repeatable ventilation performance within clinically safe limits. Due to its low power consumption, portability, and affordability, the proposed ventilator is well suited for use in rural healthcare centers, ambulances, and emergency disaster-response situations.

Keywords -Ventilator, Bag Valve Mask (BVM), Low-Cost, Low-Power, Portable, Automated Ventilation