We propose a flow meter that, unlike turbine or pressure-based sensors, is not flow intrusive, requires zero maintenance, has low risk of clogging, and is compatible with harsh conditions. Using optical fiber sensing, we monitor the temperature distribution along a fluid conduit. Pulsed heat. The method is experimentally validated for water and ethanol using optical frequency-domain reflectometry (OFDR) with millimetric spatial resolution over a 1.
[pdf] PX4 FLOW is a smart camera processing optical flow directly on the camera module. Its main output is a UART or I2C stream of flow measurements at ~400 Hz. It can be used to determine speed when navigating without GNSS — in buildings, underground, or in any other GNSS-denied environment. It has a native resolution of 752x480 pixels and calculates optical flow on a 4x binned and cropped area at 400 Hz, giving it a very high light sensitivity. Unlike many mouse sensors, it also works indoors and in low outdoor light conditions without the need. Optical Flow uses a downward facing camera and a downward facing distance sensor for velocity estimation.
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