swaroophangal / magneticimager

A magnetic imaging tile constructed from an array of Hall Effect sensors

Magnetic Imaging Tile

Work-in-progress. Please use at your own risk.

This is a board intended to function as a "magnetic field camera", and visualize magnetic fields. In it's current form, it consists of an array of 12x12 hall effect sensors (144 total) that sense magnetic fields, arrayed in a 4mm grid. Each sensor is connected to an array of analog switches, that allow an individual sensor to be addressed. Read out is accomplished one magnetic "pixel" at a time, selecting a given hall sensor from the array, reading it's value (either using the internal ADC, or an external ADC), and repeating this process until the entire array has been read out.

The current array is designed to be tile-able, with up to four of the boards (24x24 magnetic field sensors) arrayed together.

The Arduino firmware has a framerate of approximately 10 frames per second, when the image data is streamed over the serial port and displayed using the Processing visualization. The Raspberry Pi Python example achieves approximately 30fps. The array itself is likely capable of much higher speeds, but one of the major limiting factors is currently the speed of the I2C I/O multiplexer (used to select which magnetometer to read from).

For more information (and a video of the tile in use), please see: https://hackaday.io/project/18518-iteration-8/log/64376-a-magnetic-imager-tile

Open Source

This project is open source software and hardware, and is released under various open licenses.

Disclaimer

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