  In the COVID-19 period, the number of deaths has increased every day around
the world. The pandemic has impacted the life and economy. Especially, there is
a shortage in medical including a lack of technology, facility and equipment.
One of those, ventilators are the essential equipment that does not provide
enough requirements for the hospital. A ventilator is an essential unit in
hospitals because it seems to be the first step to protect the life of the
patient getting sick. Some low-income countries aim to make a simple ventilator
using locally available and low-cost materials for primary care and palliative
care. One of the simple principles of ventilators is to adopt an artificial
manual breath unit (AMBU) bag with paddles. Unfortunately, the squeezing angle
of paddles is not proportional to the exhaust air volume from the AMBU bag.
This paper analyzes the character of the squeezing angle of the paddles and the
exhaust air volume of the adult AMBU bag through experiments. The result can be
used to control the squeezing angle through a DC motor mounted with paddles to
obtain the desired air volume.
