Dynamic down sampling of position tracking data

Patent metadata

Field	Value
Publication number	US-12535599-B2
Application number	US-202318543907-A
Country	US
Kind code	B2
Filing date	Dec 18, 2023
Priority date	Dec 18, 2023
Publication date	Jan 27, 2026
Grant date	Jan 27, 2026

Abstract

Dynamically down sampling vehicle tracking data is provided. The method comprises receiving an original set of position data points from a vehicle, including a first and last data point. Each data point includes a timestamp. A path for the vehicle in four-dimensional hyperspace is simplified from the original set of points according to the Ramer-Douglas-Peucker algorithm. Positions are converted to three-dimension coordinates on a sphere with the timestamp comprising the fourth dimension. The simplified path comprises a reduced set of points that describe a minimum contiguous path of line segments between the first and last data points. All other position points from the original set satisfy a proximity criterion with regard to the minimum contiguous path. The reduced set represents the original set within a specified hyperspace tolerance and has a lower transmission bandwidth requirement. The reduced set of position points is then transmitted to users.

First claim

What is claimed is:

1 . A computer-implemented method of dynamically down sampling vehicle tracking data, the method comprising:
receiving an original set of position data points from a vehicle, wherein the set includes a first data point and a last data point, and wherein each data point includes a respective timestamp; simplifying a path for the vehicle in four-dimensional hyperspace from the original set of position data points according to the Ramer-Douglas-Peucker algorithm to reduce real-time transmission burdens, wherein positions are converted to three-dimension Cartesian XYZ coordinates on a sphere with the timestamp comprising the fourth dimensional coordinate, and wherein the simplified path comprises a reduced set of position data points that describe a minimum contiguous path of line segments between the first data point and last data point such that all other position data points from the original set satisfy a proximity criterion with regard to the minimum contiguous path of line segments, and wherein the reduced set of position data points represents the original set of position data points within a specified hyperspace tolerance, wherein a time scaling coefficient applied to the proximity criterion provides velocity-dependent correction such that projection of the hyperspace tolerance into Cartesian spatial dimensions X,Y,Z remains a sphere of constant tolerance radius for any given value of time across changes in velocity of the vehicle, and wherein the reduced set of position data points has a lower transmission bandwidth requirement than the original set of position data points; and transmitting the reduced set of position data points to a number of users.

2 . The method of claim 1 , wherein the proximity criterion comprises a threshold perpendicular hyperdistance from the line segments of the minimum contiguous path of line segments.

3 . The method of claim 1 , wherein the time scaling coefficient is applied as a scaling matrix to calculate perpendicular hyperdistances of position data points from line segments of the minimum contiguous path of line segments.

4 . The method of claim 1 , wherein the tracking data comprises automatic identification system (AIS) data.

5 . The method of claim 1 , wherein the tracking data is received in real-time.

6 . The method of claim 1 , wherein the tracking data comprises historical data.

7 . The method of claim 1 , wherein the reduced set of position data points exclude movements of the vehicle an inner boundary and buffer zone of a geofence area that do not represent true ingress or egress from the geofenced area.

8 . A system for dynamically down sampling vehicle tracking data, the system comprising:
a storage device that stores program instructions; one or more processors operably connected to the storage device and configured to execute the program instructions to cause the system to: receive an original set of position data points from a vehicle, wherein the set includes a first data point and a last data point, and wherein each data point includes a respective timestamp; simplify a path for the vehicle in four-dimensional hyperspace from the original set of position data points according to the Ramer-Douglas-Peucker algorithm to reduce real-time transmission burdens, wherein positions are converted to three-dimension Cartesian XYZ coordinates on a sphere with the timestamp comprising the fourth dimensional coordinate, and wherein the simplified path comprises a reduced set of position data points that describe a minimum contiguous path of line segments between the first data point and last data point such that all other position data points from the original set satisfy a proximity criterion with regard to the minimum contiguous path of line segments, and wherein the reduced set of position data points represents the original set of position data points within a specified hyperspace tolerance, wherein a time scaling coefficient applied to the proximity criterion provides velocity-dependent correction such that projection of the hyperspace tolerance into Cartesian spatial dimensions X,Y,Z remains a sphere of constant tolerance radius for any given value of time across changes in velocity of the vehicle, and wherein the reduced set of position data points has a lower transmission bandwidth requirement than the original set of position data points; and transmit the reduced set of position data points to a number of users.

9 . The system of claim 1 , wherein the proximity criterion comprises a threshold perpendicular hyperdistance from the line segments of the minimum contiguous path of line segments.

10 . The system of claim 8 , wherein the time scaling coefficient is applied as a scaling matrix to calculate perpendicular hyperdistances of position data points from line segments of the minimum contiguous path of line segments.

11 . The system of claim 1 , wherein the tracking data comprises automatic identification system (AIS) data.

12 . The system of claim 1 , wherein the tracking data is received in real-time.

13 . The system of claim 1 , wherein the tracking data comprises historical data.

14 . The system of claim 8 , wherein the reduced set of position data points exclude movements of the vehicle an inner boundary and buffer zone of a geofence area that do not represent true ingress or egress from the geofenced area.

15 . A computer program product for dynamically down sampling vehicle tracking data, the computer program product comprising:
a computer-readable storage medium having program instructions embodied thereon to perform the steps of: receiving an original set of position data points from a vehicle, wherein the set includes a first data point and a last data point, and wherein each data point includes a respective timestamp; simplifying a path for the vehicle in four-dimensional hyperspace from the original set of position data points according to the Ramer-Douglas-Peucker algorithm to reduce real-time transmission burdens, wherein positions are converted to three-dimension Cartesian XYZ coordinates on a sphere with the timestamp comprising the fourth dimensional coordinate, and wherein the simplified path comprises a reduced set of position data points that describe a minimum contiguous path of line segments between the first data point and last data point such that all other position data points from the original set satisfy a proximity criterion with regard to the minimum contiguous path of line segments, and wherein the reduced set of position data points represents the original set of position data points within a specified hyperspace tolerance, wherein a time scaling coefficient applied to the proximity criterion provides velocity-dependent correction such that projection of the hyperspace tolerance into Cartesian spatial dimensions X,Y,Z remains a sphere of constant tolerance radius for any given value of time across changes in velocity of the vehicle, and wherein the reduced set of position data points has a lower transmission bandwidth requirement than the original set of position data points; and transmitting the reduced set of position data points to a number of users.

16 . The computer program product of claim 15 , wherein the proximity criterion comprises a threshold perpendicular hyperdistance from the line segments of the minimum contiguous path of line segments.

17 . The computer program product of claim 15 , wherein the time scaling coefficient is applied as a scaling matrix to calculate perpendicular hyperdistances of position data points from line segments

Assignees

• S&P Global Inc

Inventors

• Parker Barnaby Scott

Classifications

• G01S19/07

  providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections · CPC title

• G01S19/52 Primary

  Determining velocity · CPC title

• G01S5/0244

  Accuracy or reliability of position solution or of measurements contributing thereto · CPC title

• G01S5/0294 Primary

  Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering · CPC title