A flow meter, and related system and method are provided. The flow meter includes a coupler, a support member, an image sensor, a valve, and one or more processors. The coupler is adapted to couple to a drip chamber. The support member is operatively coupled to the coupler. The image sensor has a field of view and is operatively coupled to the support member. The image sensor is positioned to view the drip chamber within the field of view. The one or more processors are operatively coupled to the image sensor to receive image data therefrom and to the actuator to actuate the valve. The one or more processors are configured to estimate a flow of fluid through the drip chamber and to actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate.