US 11,809,639 B2
Pedestrian sensor accuracy with minimal dependence on magnetometer
William Morrison, San Francisco, CA (US); Hsiao Chien Liang, San Jose, CA (US); Gautam Nirula, San Jose, CA (US); and Himanshu Shah, Milpitas, CA (US)
Assigned to QUALCOMM Incorporated, San Diego, CA (US)
Filed by QUALCOMM Incorporated, San Diego, CA (US)
Filed on Sep. 29, 2021, as Appl. No. 17/489,190.
Prior Publication US 2023/0107423 A1, Apr. 6, 2023
Int. Cl. G06F 3/0346 (2013.01); G01C 25/00 (2006.01); G06F 3/038 (2013.01)
CPC G06F 3/0346 (2013.01) [G01C 25/005 (2013.01); G06F 3/038 (2013.01)] 46 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
a gyroscope for determining a rotational position of the apparatus;
a gyroscope temperature sensor for measuring temperatures of the gyroscope;
memory; and
at least one processor, communicatively coupled at least to the memory, and configured to:
estimate a set of gyroscopic biases for a plurality of temperatures or temperature ranges to create a mapping that maps the plurality of temperatures or the temperature ranges to the set of gyroscopic biases;
monitor the temperatures of the gyroscope via the gyroscope temperature sensor;
calibrate the gyroscope in response to the gyroscope changing from a first temperature to a second temperature based on the mapping or based on a predicted value derived from the mapping;
identify a gyroscope-based orientation based on the calibrated gyroscope without using a magnetometer-based orientation identified by a magnetometer; and
calculate a dead reckoning (DR) trajectory of the apparatus based on the gyroscope-based orientation of the apparatus, wherein the magnetometer-based orientation is not used for calculating the DR trajectory if the gyroscope is calibrated and the magnetometer-based orientation is used for calculating the DR trajectory if the gyroscope is not calibrated.