I like to move it, move itWhat my Android device really feels

Alexander Pacha07.01.2016

About me

2008 – 2011: Bachelor of Science at University of Technology Vienna2011 – 2013: Master of Science in Munich and AugsburgSince 2014: Software Developer at ZühlkeSince 2015: Trainer Clean Code (.NET) at Zühlke Academy

My work

2013: Goldfield Explorer

2013: Sensor fusion (Master thesis)

2013 – present: SightPlayer

Hardware Sensors

Gyroscope Accelerometer Compass Camera GPSMore sensors: Light and Proximity Microphone Thermometer Barometer Hygrometer

Virtual Sensors

Calibrated Gyroscope Gravity Linear Accelerometer Orientation / Rotation Vector

Image from http://www.thousand-thoughts.com/2012/03/android-sensor-fusion-tutorial/

Filter

Image from http://www.thousand-thoughts.com/2012/03/android-sensor-fusion-tutorial/

Filters introduce latency

Demonstration

Calibrated GyroscopeOrientation / Rotation Vector

?Design thoughts

FusedResult = a * GyroOrientation + (1-a) * RotationVector

The more you move, the more you can correctFusedResult = GyroOrientation + Velocity * RotationVectorVelocityRotation = GyroX + GyroY + GyroZ

Representations

Euler-Angles: yaw, pitch and roll; Suffers from gimbal lock.

Rotation Vector: general form that specifies rotation-axis (x, y, z) and angle (α)

Rotation Matrix: 3x3 matrix that is often used in computer graphics

Quaternions: Similar to rotation vector but in 4-dimensional space.Allows interpolating (SLERP)

Demonstration

Final resulthttps://bitbucket.org/apacha/sensor-fusion-demo