10/14/2025
How is the Orientation Maintained on Message Fans?
The fan needs to know exactly where the spinning blade is at all times during its rotation to "paint" the image in the correct place, making it appear stationary.
Sensing the Starting Point: A small position encoder on the motor shaft or a Hall effect sensor (which detects a magnet placed on the stationary part of the fan body) is used to detect when the blade passes a specific, pre-determined point (e.g., the top of the circle). This is the synchronization pulse.
Timing the Pixels: Once the synchronization pulse is received, a microcontroller (a tiny computer on the fan blade's circuit board) starts a precise internal timer and tracks the angular position of the blade.
Flashing the LEDs: The microcontroller calculates the exact moment the fan blade's LED array has rotated to the position of the next "column" of the message. It then instructs the individual LEDs to flash on or off in a specific pattern to form that column of the text.
Creating the Image: As the blade continues to spin, the microcontroller repeats this process, flashing the LEDs at thousands of points around the circle in perfect timing. The blade's physical movement provides the horizontal "space" for the image, while the column of LEDs provides the vertical "pixels."
Because the fan is spinning fast, your eye retains the light from each flash just long enough until the next flash occurs in an adjacent spot, and your brain blends all these rapidly changing spots of light into a single, coherent, and stationary image (the message)
And it only costs $1.50 to make it.
