Granted Patent B2

US 12,487,250 · App. 18/202,796 · Granted Dec 2, 2025

Inventors: Wenjun Jiang (San Jose, CA); Tianwei Xing (Santa Clara, CA); Xun Chen (Fremont, CA)

Assignee: SAMSUNG ELECTRONICS CO., LTD.

G01P15/18G01P3/44G01P15/0891

Abstract

Claims (58)

1 . A method for detecting a drop event of an electronic device, the method comprising:

obtaining an angular velocity and a proper acceleration of the electronic device based on sensor data received from an inertial measurement unit (IMU) sensor of the electronic device;

obtaining a centripetal acceleration of the electronic device by computing a transition matrix having respective vectors of the angular velocity, principal moments of inertia of the electronic device, and a position of the IMU sensor within the electronic device, as inputs to the transition matrix;

based on an acceleration difference between the centripetal acceleration and the proper acceleration, determining whether the electronic device is in a fall state; and

based on the electronic device being determined to be in the fall state, providing an analysis result of the drop event.

2 . The method of claim 1 , further comprising:

determining that the electronic device is in the fall state when the acceleration difference between the centripetal acceleration and the proper acceleration is less than a first predetermined threshold.

3 . The method of claim 1 , further comprising:

determining that the electronic device is in the fall state when the angular velocity is not within a measurement range of the IMU sensor and truncation of the sensor data has occurred.

4 . The method of claim 1 , wherein a first trigger condition is satisfied when the acceleration difference between the centripetal acceleration and the proper acceleration is less than a first predetermined threshold, and a second trigger condition is satisfied when the angular velocity is not within a measurement range of the IMU sensor and truncation of the sensor data has occurred,

wherein the method further comprises:

determining that the electronic device is in the fall state when at least one of the first trigger condition and the second trigger condition is satisfied and a magnitude of the proper acceleration in a z-axis direction of the electronic device is less than a second predetermined threshold, wherein the z-axis direction of the electronic device is a direction in which a shortest side of the electronic device extends.

5 . The method of claim 1 , further comprising:

based on the electronic device being determined to be in the fall state, increasing a sampling rate for collecting the sensor data from the IMU sensor.

6 . The method of claim 1 , further comprising:

detecting an impact on the electronic device based on a magnitude of the proper acceleration;

based on the impact being detected, determining a fall duration during which the electronic device maintains the fall state until the impact is detected; and

verifying the drop event of the electronic device based on the fall duration.

7 . The method of claim 6 , wherein the detecting of the impact on the electronic device comprises:

determining that the impact has occurred based on the magnitude of the proper acceleration, and at least one of a change of the angular velocity over time, a change of the proper acceleration over time, and a magnitude of the proper acceleration in a z-axis direction of the electronic device,

wherein the z-axis direction of the electronic device is a direction in which a shortest side of the electronic device extends.

8 . The method of claim 1 , further comprising:

determining the principal moments of inertia of the electronic device based on predetermined principal moments of inertia of a device type corresponding to the electronic device, and angular velocity data and proper acceleration data collected during previous drops of the electronic device.

9 . The method of claim 8 , wherein the determining of the principal moments of inertia of the electronic device further comprises:

applying an objective function to the predetermined principal moments of inertia, and a variance of the angular velocity data and the proper acceleration data collected during the previous drops of the electronic device, to minimize a variance of rotational kinetic energy while minimizing a difference between the principal moments of inertia of the electronic device and the predetermined principal moments of inertia.

10 . An electronic device for detecting a drop event, the electronic device comprising:

an inertial measurement unit (IMU) sensor configured to collect sensor data that indicates an angular velocity and a proper acceleration of the electronic device;

at least memory storing instructions; and

at least one processor configured to execute the instructions to:

obtain the angular velocity and the proper acceleration of the electronic device based on the sensor data;

obtain a centripetal acceleration of the electronic device by computing a transition matrix having respective vectors of the angular velocity, principal moments of inertia of the electronic device, and a position of the IMU sensor within the electronic device, as inputs to the transition matrix;

based on an acceleration difference between the centripetal acceleration and the proper acceleration, determine whether the electronic device is in a fall state; and

based on the electronic device being determined to be in the fall state, provide an analysis result of the drop event.

11 . The electronic device of claim 10 , wherein the at least one processor is further configured to execute the instructions to:

determine that the electronic device is in the fall state when the acceleration difference between the centripetal acceleration and the proper acceleration is less than a first predetermined threshold.

12 . The electronic device of claim 10 , wherein the at least one processor is further configured to execute the instructions to:

determine that the electronic device is in the fall state when the angular velocity is not within a measurement range of the IMU sensor and truncation of the sensor data has occurred.

13 . The electronic device of claim 10 , wherein a first trigger condition is satisfied when the acceleration difference between the centripetal acceleration and the proper acceleration is less than a first predetermined threshold, and a second trigger condition is satisfied when the angular velocity is not within a measurement range of the IMU sensor and truncation of the sensor data has occurred,

wherein the at least one processor is further configured to execute the instructions to:

determine that the electronic device is in the fall state when at least one of the first trigger condition and the second trigger condition is satisfied and a magnitude of the proper acceleration in a z-axis direction of the electronic device is less than a second predetermined threshold, wherein the z-axis direction of the electronic device is a direction in which a shortest side of the electronic device extends.

14 . The electronic device of claim 10 , wherein the at least one processor is further configured to execute the instructions to:

based on the electronic device being determined to be in the fall state, increase a sampling rate for collecting the sensor data from the IMU sensor.

15 . The electronic device of claim 10 , wherein the at least one processor is further configured to execute the instructions to:

detect an impact on the electronic device based on a magnitude of the proper acceleration;

based on the impact being detected, determine a fall duration during which the electronic device maintains the fall state until the impact is detected; and

verify the drop event of the electronic device based on the fall duration.

16 . The electronic device of claim 15 , wherein the at least one processor is further configured to execute the instructions to:

determine that the impact has occurred based on the magnitude of the proper acceleration, and at least one of a change of the angular velocity over time, a change of the proper acceleration over time, and a magnitude of the proper acceleration in a z-axis direction of the electronic device,

wherein the z-axis direction of the electronic device is a direction in which a shortest side of the electronic device extends.

17 . The electronic device of claim 10 , wherein the at least one processor is further configured to execute the instructions to:

determine the principal moments of inertia of the electronic device based on predetermined principal moments of inertia of a device type corresponding to the electronic device, and angular velocity data and proper acceleration data collected during previous drops of the electronic device.

18 . The electronic device of claim 17 , wherein the at least one processor is further configured to execute the instructions to:

apply an objective function to the predetermined principal moments of inertia and a variance of the angular velocity data and the proper acceleration data collected during the previous drops of the electronic device, to minimize a variance of rotational kinetic energy while minimizing a difference between the principal moments of inertia of the electronic device and the predetermined principal moments of inertia.

19 . A non-transitory computer readable storage medium that stores instructions to be executed by at least one processor to perform a method for detecting a drop event of an electronic device, the method comprising:

obtaining an angular velocity and a proper acceleration of the electronic device based on sensor data received from an inertial measurement unit (IMU) sensor of the electronic device;

obtaining a centripetal acceleration of the electronic device by computing a transition matrix having respective vectors of the angular velocity, principal moments of inertia of the electronic device, and a position of the IMU sensor within the electronic device;

based on an acceleration difference between the centripetal acceleration and the proper acceleration, determining whether the electronic device is in a fall state; and

based on the electronic device being determined to be in the fall state, providing an analysis result of the drop event.

Assignments (1)

Continuity (2)

References Cited (21)