Folding Angle Detection

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Video #07

Tri-axis magnetic sensor, AK0997x is the most suitable sensor for measuring strong magnetic fields in magnets.
The magnetic sensitivity in three axis directions makes it easy to detect from which direction the magnetic field is being applied to the sensor.
Even for the complicated foldable structure using special hinges, the AK0997x can estimate a folding angle by detecting 3D magnetic variation associated with folding motion. The AK0997x is suitable for screen folding angle detection at foldable phones because it's housed in a small package and it has wide measurement range each axis.
In this demo video, we show you that folding operation, detection mechanism, proposed application and the demo kit.

#01

What kind of demo?

  • Folding angle detection using tri-axis magnetic sensor
  • Easily detects folding angle without dependence on mobile terminal posture
  • Simple configuration with a tri-axis magnetic sensor and a single magnet

#02

How do you detect it?

  • The sensor moves according to the folding action, and the magnetic field applied from the magnet changes.
  • Making the reference table between applied magnetic field and folding angle for initial calibration
  • After initial calibration, you can get folding angle only using output data from tri-axis magneitc sensor. Accuracy does not depend on terminal posture
  • The magnetic field generated outside of the folding motion can be detected as a disturbance field

#03

For what purpose?

  • GUI changing function depending on folding angle of foldable smartphones
  • Web camera and monitor brightness/colorfulness adjustment function is appropriate to folding angle of note PCs
  • Detecting the angle of finger bending in VR gloves

#04

Detail of Demo kit

  • Sensor (AK09970D) / magnet / MCU / LED for angle checking / foldabe body are provided
  • The magnet is attached to a hinge part, and the sensor is mounted in a position (e.g., screen) that moves according to the folding motion 
  • Making the reference table between applied magnetic field and folding angle for initial calibration
  • LEDs turn on/off depending on folding angle situation
  • Accuracy of folding angle detection does not depend on terminal posture
  • 4th LED turns on when magnetic disturbance is detected