US 12,247,886 B2
Sensor calibration
Sasu Tarkoma, Helsingin Yliopisto (FI); Tuukka Petäjä, Helsingin Yliopisto (FI); Markku Kulmala, Helsingin Yliopisto (FI); and Joni Kujansuu, Helsingin Yliopisto (FI)
Assigned to University of Helsinki, Helsingin Yliopisto (FI)
Appl. No. 16/976,194
Filed by University of Helsinki, Helsingin Yliopisto (FI)
PCT Filed Mar. 22, 2019, PCT No. PCT/FI2019/050242
§ 371(c)(1), (2) Date Aug. 27, 2020,
PCT Pub. No. WO2019/180325, PCT Pub. Date Sep. 26, 2019.
Claims priority of application No. 20185271 (FI), filed on Mar. 22, 2018.
Prior Publication US 2021/0003461 A1, Jan. 7, 2021
Int. Cl. G01K 15/00 (2006.01); G08C 23/00 (2006.01)
CPC G01K 15/005 (2013.01) [G08C 23/00 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising calibrating a first sensor in a changing operating environment in a calibration process that comprises:
receiving sensor data from the first sensor;
receiving sensor values from a known calibrating sensor;
obtaining a localized sensor map and profile for the first sensor:
maintaining a sensor specific model for the first sensor using the localized sensor map and profile;
detecting calibration needs by estimating a drift and error of the sensor data, taking into account a difference between the sensor data from the first sensor and the sensor values from the calibrating sensor; and
estimating a correction factor or a correction model to the sensor data using said difference and the sensor specific model; and
using the estimated correction factor or correction model for calibrating the first sensor;
wherein the calibrating sensor is a virtual sensor based on a model of sensor data provided by one or more calibrated sensors,
wherein the calibrating sensor is ranked higher than the first sensor in a hierarchical model,
wherein the first sensor, the calibrating sensor and additional sensors form groups of sensors communicating with each other via a sensor network, and
wherein calibration is performed inside a node of the sensor network and between nodes of the sensor network to provide for improving accurate sensing capabilities.