The motor with optical control uses a flat opaque disk with four blades attached to the rotor. If you're interested in the field of robotics and computer vision systems, you've likely heard of optic flow sensors. But what exactly are they, and how are they used. PMW3901 is an optical flow ASIC that computes the flow internally and provides a difference in pixels between each frame. It uses a tracking sensor that is similar to what you would find in a computer mouse, but adapted to work between 80 mm and infinity. It can be used to determine speed when navigating without GNSS — in buildings, underground, or in any other GNSS-denied environment.
[pdf] Design of a current sensor based on optical fibers This paper present the design of a current sensor based on Faraday Effect using optical fibers devices and a polarizing beam splitter (PBS). Two different schematics are to be taken into account, for high currents. Accurate measurement of electrical current in devices is a fundamental technology that is essential for controlling and monitoring the systems and equipment that many industries and our daily lives depend upon. Typically, current transformers have been used to measure electric current. The superposition principle of composite OAM beam is deduced, and the current sensing process is derived by Jones matrix.
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