METHOD AND SYSTEM FOR CALCULATING AND DISPLAYING TRAVEL RANGE INFORMATION

• US 20110298640A1
• Filed: 06/04/2010
• Published: 12/08/2011
• Est. Priority Date: 06/04/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Tate, Edward D. Jr.
• Granted Patent: US 8,527,121 B2
• Time in Patent Office: Days
• US Class Current: 340/995.1
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 2260/52 drive range estimation, e.g. of estimation of available travel distance
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 50/62 charged by low-power generators primarily intended to support the batteries, e.g. range extenders
• CPC Class Codes: G01C 21/3667 Display of a road map G01C21/3614 takes precedence; guidance using 3D or perspective road maps G01C21/3635
• CPC Class Codes: G01C 21/3697 Output of additional, non-guidance related information, e.g. low fuel level G01C21/3679 takes precedence
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A display system for a vehicle includes a display screen and host machine operable for calculating a maximum theoretical range for a predetermined criterion, formulating a value function for each point in the maximum theoretical range, and calculating a solution to each of the value functions. The method also includes forming a polygon or a closed curve from the mathematical hull of all points in the maximum theoretical range having a value function solution less than corresponding limit, and displaying a perimeter of the closed curve via the display screen to indicate the effective range of the vehicle for the criterion. A vehicle includes an energy storage system, a motor/generator unit for propelling the vehicle in an electric-only (EV) mode, the display screen, and host machine, wherein the criterion is the EV mode. A method of operating the display system is also disclosed herein.

Claims

1. A display system for a vehicle, the display system comprising:

a display screen; and

host machine in communication with a geospatial mapping database, wherein the geospatial mapping database provides a map of road segments, the host machine being operable for;

calculating a maximum theoretical range for a predetermined criterion;

formulating a value function which summarizes the minimum cost to travel from a predetermined location to each of a set of sampled points on the map within one of the maximum theoretical range and a displayable subset of the maximum theoretical range;

calculating a solution to the value function for each point in the set of sampled points using a cost which is a function of attributes of each road segment appearing on the map;

forming a closed curve from the mathematical hull of all points in the maximum theoretical range having a value function solution less than a corresponding limit; and

displaying at least a perimeter of the closed curve via the display screen to thereby indicate the effective range of the vehicle for the predetermined criterion with respect to the predetermined location.

2. The display system of claim 1, wherein the vehicle is powered exclusively by electrical power at least part of the time, and wherein the predetermined criterion is an electric-only (EV) propulsion mode, such that the perimeter is a graphical overlay which graphically indicates the effective EV range from the predetermined location with respect to the map.

3. The display system of claim 1, wherein the cost is at least one of:

time, energy, distance, and an arbitrary function of the attributes of a given one of the road segments.

4. The display system of claim 3, wherein the cost includes the arbitrary function of the attributes, and wherein the attributes include at least one of:

posted speed, historical speed, road geometry, road grade, and traffic control devices on the given one of the road segments.

5. The display system of claim 1, wherein the value function is calculated with respect to a position of a charging station with respect to the predetermined location.

6. The display system of claim 1, wherein the host machine uses a Voronoi diagram to define a perimeter of the closed curve.

7. The display system of claim 1, wherein the host machine calculates a solution to each of the value functions using one of an approximation method and a fixed point iterative algorithm.

8. A vehicle comprising:

an energy storage system;

a motor/generator unit which is electrically connected to the energy storage system and adapted for generating torque for propelling the vehicle in an electric-only (EV) mode;

a display screen; and

host machine in communication with a geospatial mapping database, wherein the geospatial mapping database provides a map of road segments, the host machine being operable for;

calculating a maximum theoretical range for the EV mode;

formulating a value function which summarizes the minimum cost to travel from a predetermined location to each of a set of sampled points on the map within one of the maximum theoretical range and a displayable subset of the maximum theoretical range;

calculating a solution to the value function for each point in the set of sampled points using a cost which is a function of the attributes of each road segment appearing on the map;

forming a closed curve from the mathematical hull of all points in the maximum theoretical range having a value function solution less than a corresponding limit; and

displaying at least a perimeter of the closed curve via the display screen to thereby indicate the effective EV range of the vehicle with respect to the predetermined location.

9. The vehicle of claim 8, wherein the host machine processes information from a geospatial mapping database and presents a map via the display screen, and wherein the perimeter of the closed curve is a graphical overlay to the map.

10. The vehicle of claim 8, wherein the cost is at least one of:

time, energy, distance, and arbitrary function of the attributes of a given one of the road segments.

11. The vehicle of claim 10, wherein the cost includes the arbitrary function of the attributes, and wherein the attributes include at least one of:

a posted speed, an historical speed, road geometry, road grade, and traffic control device usage on the given one of the road segments.

12. The vehicle of claim 8, wherein the host machine uses a Voronoi diagram to define a perimeter of the closed curve.

13. A method of operating a display system for a vehicle, the display system having a display screen and a host machine which is in communication with a geospatial mapping database that provides a map of road segments, the method comprising:

formulating a value function which summarizes the minimum cost to travel from a predetermined location to each of a set of sampled points on the map within one of the maximum theoretical range and a displayable subset of the maximum theoretical range;

calculating a solution to the value function for each point in the set of sampled points using a cost which is a function of the attributes of each road segment appearing on the map;

forming a closed curve from the mathematical hull of all points in the maximum theoretical range having a value function solution less than a corresponding limit; and

displaying at least a perimeter of the closed curve via the display screen to thereby indicate the effective EV range of the vehicle with respect to the predetermined location.

14. The method of claim 13, wherein calculating a solution to the value function for each point using a cost includes using at least one of:

time, energy, distance, and an arbitrary function of the attributes of a given one of the road segments.

15. The method of claim 14, including the arbitrary function, wherein the attributes include at least one of:

a posted speed, an historical speed, road geometry, road grade, and traffic control device usage on the given one of the road segments.

16. The method of claim 13, further comprising calculating the value function with respect to a position of a charging station.

17. The method of claim 13, further comprising defining the perimeter of the closed curve using a Voronoi diagram.

18. The method of claim 13, wherein calculating a solution to each of the value functions includes using one of an approximation method and a fixed point algorithm.