US-12625000-B2 - Calibrating an infrared (IR) sensor in a fire sensing device

US12625000B2US 12625000 B2US12625000 B2US 12625000B2US-12625000-B2

Abstract

Devices, methods, and systems for calibrating an infrared (IR) sensor in a fire sensing device are described herein. One device includes a camera configured to capture an image of an environment, an IR sensor configured to detect a radiation level of the environment, and a controller configured to compare a radiation level of the image of the environment captured by the camera to the radiation level of the environment detected by the IR sensor and calibrate the IR sensor based on the comparison.

Inventors

Vyshnavi Rajesh
Agnel ANTO

Assignees

HONEYWELL INTERNATIONAL INC.

Dates

Publication Date: 20260512
Application Date: 20230515

Claims (12)

1 . A fire sensing device, comprising: a camera configured to capture an image of an environment; an infrared (IR) sensor; and a controller configured to: convert the image from red, green, and blue color space to a number of hue saturation values; determine whether the image includes an IR body by comparing the number of hue saturation values of the image to a number of hue saturation values of an image without an IR emitting body, wherein the image without the IR emitting body has no radiation; determine, responsive to determining the image does not include an IR body, the image has no radiation; and initiate calibration of the IR sensor responsive to determining the image has no radiation.
2 . The device of claim 1 , wherein the camera is used for flame detection.
3 . A method for calibrating a fire sensing device, comprising: capturing an image of an environment using a camera of the fire sensing device; converting the image from a red, green, and blue color space to a first number of hue saturation values; determining whether the image includes an infrared (IR) body by comparing the first number of hue saturation values of the image to a number of hue saturation values of an image without an IR emitting body, wherein the image without the IR emitting body has no radiation; determining, responsive to determining the image does not include an IR body, the image has no radiation; and calibrating an IR sensor of the fire sensing device responsive to determining the image has no radiation.
4 . The method of claim 3 , wherein the image captured by the camera is in the red, green, and blue color space.
5 . The method of claim 4 , wherein the method includes comparing the first number of hue saturation values to a number of hue saturation values detected by the IR sensor.
6 . The method of claim 3 , wherein the method includes predicting an end of life of the IR sensor based on calibration frequency of the IR sensor.
7 . The method of claim 3 , wherein calibrating the IR sensor comprises adding a correction factor to a radiation level of the environment detected by the IR sensor.
8 . A fire sensing device, comprising: a camera configured to capture an image of an environment; an infrared (IR) sensor; and a controller configured to: convert the image from a red, green, and blue color space to a number of hue saturation values; determine whether the image includes an IR body by comparing the number of hue saturation values of the image to a number of hue saturation values of an image without an IR emitting body, wherein the image without the IR emitting body has no radiation; determine, responsive to determining the image does not include an IR body, the image has no radiation; initiate calibration of the IR sensor responsive to determining the image has no radiation; and predict an end of life of the IR sensor based on calibration frequency of the IR sensor.
9 . The device of claim 8 , wherein the camera is configured to capture the image of the environment using visible light.
10 . The device of claim 8 , wherein the controller is configured to generate an alert that the IR sensor is at end of life.
11 . The device of claim 10 , wherein the controller is configured to transmit the alert.
12 . The device of claim 8 , wherein the camera is configured to capture an additional image of the environment.

Description

TECHNICAL FIELD The present disclosure relates generally to devices, methods, and systems for calibrating an infrared (IR) sensor in a fire sensing device. BACKGROUND Large facilities, such as commercial buildings, office buildings, hospitals, and the like, as well as residential buildings, such as apartments, townhomes, single family homes, and the like may have a fire alarm system that can be triggered during an emergency situation (e.g., a fire) to warn occupants to evacuate. For example, a fire alarm system may include a fire control panel and a plurality of fire sensing devices (e.g., smoke detectors), located throughout the building (e.g., on different floors and/or in different rooms of the building) that can sense a fire occurring in the building (e.g., by detecting smoke) and provide a notification of the fire to the occupants of the building via alarms. Maintaining the fire alarm system can include recalibration of the sensors of fire sensing devices of the system. Over time the sensors of a fire sensing device can drift out of a calibration due to environmental conditions. For example, infrared (IR) sensors used for flame detection can drift due to exposure to radiation. An IR sensor out of calibration can prevent a fire sensing device from detecting a flame. Recalibration of sensors often requires tedious procedures and a significant amount of time. For example, a fire sensing device may have to be dismounted and shipped offsite for calibration that involves specialized calibration equipment by trained personnel. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a block diagram of a fire sensing device in accordance with an embodiment of the present disclosure. FIG. 2 illustrates a method flow diagram of a calibration of an IR sensor in a fire sensing device in accordance with an embodiment of the present disclosure. FIG. 3 illustrates a method flow diagram of detecting an IR radiation level of an image captured by a camera in a fire sensing device in accordance with an embodiment of the present disclosure. FIG. 4 illustrates a method flow diagram of a calibration of an IR sensor in a fire sensing device in accordance with an embodiment of the present disclosure. FIG. 5 illustrates a block diagram of a fire alarm system in accordance with an embodiment of the present disclosure. DETAILED DESCRIPTION Devices, methods, and systems for calibrating an infrared (IR) sensor in a fire sensing device are described herein. One device includes a camera configured to capture an image of an environment, an IR sensor configured to detect a radiation level of the environment, and a controller configured to compare a radiation level of the image of the environment captured by the camera to the radiation level of the environment detected by the IR sensor and calibrate the IR sensor based on the comparison. In contrast to previous fire sensing devices in which a person (e.g., maintenance engineer and/or operator) would have to manually test and calibrate an IR sensor in a fire sensing device, a fire sensing device in accordance with the present disclosure can test and calibrate its IR sensor itself, without the involvement of a maintenance engineer or operator. For example, the fire sensing device can utilize a camera in the fire sensing device to determine when the fire sensing device is in extreme darkness, which means the IR sensor should record a value of zero. If the IR sensor records a value other than zero, this can indicate that the IR sensor needs to be recalibrated, and the value can be used to calibrate (e.g., recalibrate) the IR sensor. Accordingly, fire sensing devices in accordance with the present disclosure may test their IR sensor, recalibrate their IR sensor, and/or transmit an alert that the IR sensor is out of calibration, which can reduce the chance of the fire sensing device delaying or missing the detection of a fire. In the following detailed description, reference is made to the accompanying drawings that form a part hereof. The drawings show by way of illustration how one or more embodiments of the disclosure may be practiced. These embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice one or more embodiments of this disclosure. It is to be understood that other embodiments may be utilized and that mechanical, electrical, and/or process changes may be made without departing from the scope of the present disclosure. As will be appreciated, elements shown in the various embodiments herein can be added, exchanged, combined, and/or eliminated so as to provide a number of additional embodiments of the present disclosure. The proportion and the relative scale of the elements provided in the figures are intended to illustrate the embodiments of the present disclosure and should not be taken in a limiting sense. The figures herein follow a numbering convention in which the first digit or digits correspond to the drawing figure number and the