Mounting angle calibration for an in-vehicle accelerometer device

• Main Author: McKown Russell Carl
• Format: Patent
• Language: English
• Published: 21.03.2017
• Subjects: INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT; MEASURING; MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION,OR SHOCK; PHYSICS; TESTING

The present application provides a system, method and non-transitory computer readable medium for mounting angle estimation and compensation for in-vehicle devices with an accelerometer sensor. In example embodiments, a two phased calibration starts with the vehicle parked on a horizontal surface and uses averaging to obtain mean value estimates of the force due to gravity on each directly coupled accelerometer sensor axis. These mean value estimates are used to perform an axes reassignment, if necessary, and to estimate the pitch and roll mounting angles. The calibration is completed by estimating the yaw mounting angle while the vehicle is driven. The yaw estimate is based on acceleration data in the vehicle's x-y plane that is accumulated when the amplitude is above a threshold. The accumulation includes a sign change if forward deceleration is indicated. Calibration provides a coordinate transformation matrix that is used during device operation to transform the sensor data into the standard vehicle body coordinates for subsequent device-dependent application processing.