Method and module for determining of velocity reference values for a vehicle control system
A method for determination of speed set-point values v ref for a vehicle's control systems, includes determining a horizon from 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; calculating speed set-point values v ref for the vehicle's control systems across the horizon according to rules pertaining to the classes in which segments within the horizon are placed; adding an offset v offset to the calculated speed set-point values v ref when the vehicle is in a segment which is in a category indicating a steep upgrade or a steep downgrade; regulating the vehicle according to the speed set-point values v ref . A module determines of speed set-point values for a vehicle's control systems.
1. A method for determination of speed set-point values v ref for a vehicle's control systems, the method comprising:
A) determining a horizon using position data and map data of an itinerary made up of route segments with length and gradient characteristics for each segment;
B) 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;
C) 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;
D) calculating speed set-point values v ref for the vehicle's control systems across the horizon according to rules pertaining to the categories in which segments within the horizon are placed;
E) adding an offset v offset to the calculated speed set-point values v ref when the vehicle is in a segment which is in a category indicating a steep upgrade or a steep downgrade; and
F) regulating the vehicle according to the speed set-point values v ref .
2. A method according to claim 1 , in which a positive offset v offset is added to the calculated speed set-point values v ref when the vehicle is on a steep upgrade.
3. A method according to claim 1 , in which a negative offset v offset is added to the calculated speed set-point values v ref when the vehicle is on a steep downgrade.
4. A method according to claim 1 , wherein said offset v offset is a variable value over time.
5. 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 certain distance L, not allowing both acceleration and retardation of the vehicle within the section L.
6. A method according to claim 1 , wherein vehicle-specific values are determined by current transmission ratio, current vehicle weight, the engine's maximum torque curve, mechanical friction and/or the vehicle's running resistance at a current speed.
7. A method according to claim 1 , wherein threshold values are calculated in the form of gradient threshold values l min and l max .
8. A method according to claim 1 , wherein the horizon is determined by using position data from a GPS.
9. A module for determining speed set-point values for a vehicle's control systems, the module comprising:
a horizon unit configured and operable to determine a horizon using position data and map data of an itinerary made up of route segments with length and gradient characteristics for each segment;
a processor unit configured and operable to: calculate 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; compare 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; calculate speed set-point values v ref for the vehicle's control systems across the horizon according to rules pertaining to the categories in which segments within the horizon are placed; and configured and operable to add an offset v offset to the calculated speed set-point values v ref when the vehicle is in a segment which is in a category indicating a steep upgrade or a steep downgrade, after which the vehicle is regulated according to the speed set-point values v ref .
10. A module according to claim 9 , in which the processor unit is configured and operable to add a positive offset v offset to the calculated speed set-point values v ref when the vehicle is on a steep upgrade.
11. A module according to claim 9 , wherein the processor unit is configured and operable to add a negative offset v offset to the calculated speed set-point values v ref when the vehicle is on a steep downgrade.
12. A module according to claim 9 , wherein said offset v offset is a variable value over time.
13. A module according to claim 9 , wherein when a first steep upgrade or a first steep downgrade is followed by a steep upgrade or a steep downgrade within a certain distance L, the processor unit is configured and operable to not allow both acceleration and retardation of the vehicle within the section L.
14. A module according to claim 9 , wherein vehicle-specific values are determined by current transmission ratio, current vehicle weight, the engine's maximum torque curve, mechanical friction and/or the vehicle's running resistance at a current speed.
15. A module according to claim 9 , wherein the processor unit is configured and operable to calculate threshold values in the form of gradient threshold values l min and l max .
16. A module according to claim 9 , wherein the horizon unit is configured and operable to determine the horizon by using position data from a GPS.
17. A computer program product comprising computer program instructions for enabling a computer system in a vehicle to perform a method for determination of speed set-point values v ref for a vehicle's control systems, the method comprising:
A) determining a horizon using position data and map data of an itinerary made up of route segments with length and gradient characteristics for each segment;
B) 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;
C) 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;
D) calculating speed set-point values v ref for the vehicle's control systems across the horizon according to rules pertaining to the categories in which segments within the horizon are placed;
E) adding an offset v offset to the calculated speed set-point values v ref when the vehicle is in a segment which is in a category indicating a steep upgrade or a steep downgrade; and
F) regulating the vehicle according to the speed set-point values v ref ,
wherein the computer program instructions are stored on a non-transitory medium which is readable by a computer system.