Method and module for controlling a velocity of a vehicle

• US 8,620,558 B2
• Filed: 05/31/2010
• Issued: 12/31/2013
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Scania CV AB (Volkswagen AG)
• Original Assignee: Scania CV AB (Volkswagen AG)
• Inventors: Johansson, Oskar, Hansson, Jrgen, Pettersson, Henrik, Sdergren, Maria
• Primary Examiner(s): Cheung, Mary
• Assistant Examiner(s): MAZZARA, ANNE MARIE
• Application Number:
  US13/377,185
• Publication Number:
  US 20120083985A1
• Time in Patent Office: 1,310 Days
• Field of Search: 701/93, 701/96, 701/7, 701/931, 180/170
• US Class Current: 701/93
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 40/06 Road conditions
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration

Abstract

A method for regulating a vehicle'"'"'s speed including the steps of: determining a horizon by means of position data and map data of an itinerary made up of route segments with length and gradient characteristics for each segment; calculating threshold values for the gradient of segments according to one or more vehicle-specific values, which threshold values serve as boundaries for assigning segments to various categories; comparing the gradient of each segment with the threshold values and placing each segment within the horizon in a category according to the results of the comparisons; and, for each segment within the horizon which is in a category indicating a steep upgrade or a steep downgrade, calculating the vehicle'"'"'s final speed v_end after the end of the segment, based inter alia on the entry speed v_i to the segment; and determining the entry speed v_i for said segment based on the calculated final speed vend for the segment, which determination is defined by rules for said segment'"'"'s category, so that the vehicle'"'"'s final speed v_end is within the range defined by v_max and v_min for the vehicle'"'"'s current reference speed v_set, on the supposition that v_i is determined within the same range; and regulating the vehicle'"'"'s speed according to speed set-point values v_ref based on the entry speeds v_i to each segment.

Claims

1. A method performed by a control system incorporating a computer for regulating a vehicle'"'"'s speed, the method comprising:

determining a horizon from position data and map data of an itinerary including route segments, each route segment having a with length, an end, and gradient characteristics;

calculating threshold values according to one or more vehicle-specific values;

comparing the gradient characteristics of each segment with the threshold values and assigning each segment within the horizon to a respective category according to the results of the comparisons, wherein the threshold values serve as boundaries for assigning the segments to the respective categories;

for each segment within the horizon assigned to a category indicating a steep upgrade or a steep downgrade, the method comprises;

calculating the vehicle'"'"'s final speed V_end, the final speed V_end being a speed immediately after the end of the segment, based inter alia on an entry speed v_i to the segment; and

when the calculated final speed V_end is outside a range for the vehicle'"'"'s current reference speed v_set defined by V_max and V_min, the method comprises;

correcting the entry speed v_i for the segment on the basis of the calculated final speed V_end for the segment,

wherein the correction is defined by rules for the segment'"'"'s assigned category, so that V_min≦

V_end≦

V_max, on the supposition that v_i is corrected within the same range; and

regulating the vehicle'"'"'s speed according to speed set-point values V_ref based on a respective entry speed v_i for each segment.

2. A method according to claim 1, wherein the vehicle-values are determined by current transmission ratio, current vehicle weight, a maximum torque curve of an engine of the vehicle, mechanical friction and/or the vehicle'"'"'s running resistance at current speed.

3. A method according to claim 1, further comprising calculating the vehicle'"'"'s final speed V_end based also on a force F_track acting from an engine torque in the vehicle'"'"'s direction of movement, a force F_roll which is a rolling resistance acting upon the vehicle'"'"'s wheels, a force F_α

acting upon the vehicle because of a gradient α

of the segment, and a running resistance.

4. A method according to claim 1, wherein the correcting of the entry speed v_i for the segment further comprises:

determining the entry speed v_i to the segment according to the length of the segment, whereby a maximum correction of the entry speed v_i is determined by a calculated maximum acceleration or retardation according to rules for the segment categories.

5. A method according to claim 4, wherein the determination of the entry speed v_i involves entry speeds which occur in earlier segments being determined according to the rules for the segment categories so that said entry speed v_i can be fulfilled.

6. A method according to claim 1, further comprising ramping a requested speed change between two consecutive entry speeds v_i to provide the control system with gradually increasing or decreasing speed set-values V_ref.

7. A method according to claim 1, further comprising when a first steep upgrade or a first steep downgrade is followed by a steep upgrade or a steep downgrade within a section. L, preventing both acceleration and retardation of the vehicle within the section L.

8. A module for regulating a vehicle'"'"'s speed, the module comprising:

a horizon unit configured and operable to determine a horizon based on received position data and map data of an itinerary including route segments, each route segment having a length, an end, and a gradient characteristic;

a processor unit that includes a data processor, the processor unit configured and operable;

to calculate threshold values according to one or more vehicle-specific values;

to compare the gradient characteristic of each segment with the threshold values and to assign each segment within the horizon to a respective category according to the results of the comparisons, wherein the threshold values serve as boundaries for assigning the segments to the respective categories; and

for each segment within the horizon assigned to a category indicating a steep upgrade or a steep downgrade, the processor unit is configured and operable to;

calculate the vehicle'"'"'s final speed V_end, the final speed being a speed immediately after the end of the segment, based inter alia on the entry speed v_i to the segment; and

correct the entry speed v_i for the segment based on the calculated final speed V_end for the segment, wherein the correction is defined by rules for the segment'"'"'s assigned category, so that V_min≦

V_end≦

V_max, on the supposition that v_i is corrected within the same range; and

a control system configured and operable to regulate the vehicle'"'"'s speed according to speed set-point values V_ref based on a respective entry speed v_i for each segment.

9. A module according to claim 8, wherein vehicle-specific values are determined by current transmission ratio, current vehicle weight, a maximum torque curve of an engine of the vehicle, mechanical friction and/or the vehicle'"'"'s running resistance at current speed.

10. A module according to claim 8, wherein the processor unit is configured and operable to calculate the vehicle'"'"'s final speed V_end based also on a force F_track acting from engine torque in the vehicle'"'"'s direction of movement, a force F_roll which is a rolling resistance acting upon the vehicle'"'"'s wheels, a force F_α

acting upon the vehicle because of a gradient a of the segment, and running resistance.

11. A module according to claim 8, wherein the processor unit is configured and operable to determine the entry speed v_i to the segment according to the length of the segment, wherein a maximum correction of the entry speed v_i is determined by a calculated maximum acceleration or retardation according to rules for the segment categories.

12. A module according to claim 8, wherein the processor unit is configured and operable to ramp a requested speed change between two consecutive entry speeds v_i in order to provide the control system with gradually increasing or decreasing speed set-values V_ref.

13. A module according to claim 8, wherein when the processor unit is determining an entry speed % the processor unit is also configured and operable to determine entry speeds which occur in earlier segments according to the rules for the segment categories so that the entry speed v_i can be fulfilled.

14. A module according to claim 8, wherein when a first steep upgrade or a first steep downgrade is followed by a steep upgrade or a steep downgrade within a section L, the processor unit is configured and operable to not allowing both acceleration and retardation of the vehicle within the section L.

15. A computer-readable medium incorporating a non-transitory program product comprising computer program of instructions for enabling a computer system in a vehicle to perform the steps of:

determining a horizon from position data and map data of an itinerary

including route segments, each route segment having a with length, an end, and gradient characteristics;

calculating threshold values according to one or more vehicle-specific values;

comparing the gradient characteristics of each segment with the threshold values and assigning each segment within the horizon to a respective category according to the results of the comparisons, wherein the threshold values serve as boundaries for assigning the segments to the respective categories;

for each segment within the horizon assigned to a category indicating a steep upgrade or a steep downgrade, the method comprises;

calculating the vehicle'"'"'s final seed V_end, the final seed V_end being a speed immediately after the end of the segment, based inter alia on an entry speed v_i to the segment; and

when the calculated final speed Vend is outside a range for the vehicle'"'"'s current reference seed v_set defined by V_max and V_min, the method comprises;

correcting the entry seed v_i for the segment on the basis of the calculated final speed V_end for the segment,

wherein the correction is defined by rules for the segment'"'"'s assigned category, so that V_min≦

V_end≦

V_max, on the supposition that v_i is corrected within the same range; and

regulating the vehicle'"'"'s speed according to speed set-point values V_ref based on a respective entry seed v_i for each segment

when the computer program of instructions is run on the computer system.

16. A computer-readable medium program product according to claim 15, wherein the computer system is on-board the vehicle.