Module and method pertaining to mode choice when determining reference values

• US 9,376,109 B2
• Filed: 12/22/2011
• Issued: 06/28/2016
• Est. Priority Date: 12/22/2011
• Status: Expired due to Fees

• Current Assignee: Scania CV AB (Volkswagen AG)
• Original Assignee: Scania CV AB (Volkswagen AG)
• Inventors: Johansson, Oskar, Sdergren, Maria, Roos, Fredrik
• Primary Examiner(s): Shaawat, Mussa A
• Assistant Examiner(s): BERNS, MICHAEL ANDREW
• Application Number:
  US14/364,817
• Publication Number:
  US 20140330503A1
• Time in Patent Office: 1,650 Days
• Field of Search: 701/93
• US Class Current: 1/1
• CPC Class Codes: B60K 31/00 Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator fittings acting on two or more sub-units B60W30/14; speedometers G01P; systems or devices for controlling speed in general G05D13/00 ; in traffic anti-collision system for road vehicles G08G1/16
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2540/215 Selection or confirmation of options
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2720/10 Longitudinal speed
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: B60W 50/08 Interaction between the driver and the control system
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration

Abstract

Described is a method for determining a reference value for a vehicle. The method includes: performing a number of simulation cycles S_j each comprising simulation steps: making a first prediction of the vehicle'"'"'s speed v_{pred_cc} along the determined horizon with a conventional cruise control; comparing, in a first comparison, the predicted vehicle speed v_{pred_cc} with v_lim1 and v_lim2, which define a motor torque used in a subsequent simulation cycle; making a second prediction of the speed when the engine torque is a value that depends on the result of said comparison in the latest preceding simulation cycle; comparing, in a second comparison, the predicted vehicle speed v_{pred_Tnew} with v_min, and v_max1 which demarcate a range within which the speed is maintained; determining the reference value based on the second comparison and/or the second predicted speed in that simulation cycle S_j; and controlling the vehicle according to the reference value.

Claims

1. A control system configured to determine at least one reference value for controlling a speed of a vehicle, the control system comprising:

a set speed input unit configured to receive at least one set speed v_set for the vehicle;

a mode choice receiving unit configured to receive a choice from at least two selectable driving modes, each driving mode comprising a setting which influences the determination of the at least one reference value;

a map data and location data-based horizon unit configured to determine an itinerary by reference to map data and location data, the horizon made up of at least one route segment with at least one characteristic;

a simulation cycle calculation unit configured to perform a number of simulation cycles s_j, each simulation cycle comprising a number N of simulation steps conducted at a predetermined rate f, the simulation steps including;

making a first prediction of the speed V_{pred_cc} of the vehicle along the horizon such that the set speed v_set is taken as a reference speed v_ref, the first prediction made based on the characteristic of said route segment;

comparing, as a first comparison, the first predicted vehicle speed v_{pred_cc} with first lower and upper limit values v_lim1 and v_lim2 to define an engine torque T, the engine torque T used in an immediately following simulation cycle s_j+1;

making a second prediction of the speed V_{pred_Tnew} of the vehicle along the horizon, the engine torque T being a value defined in said first comparison in an immediately preceding simulation cycle s<sub>j−

1</sub>; and

comparing, as a second comparison, the second predicted vehicle speed v_{pred_Tnew} with at least one of second lower and upper limit values v_min and v_max, wherein v_min and v_max delineate a range within which the speed of the vehicle is maintained; and

determining said at least one reference value along the horizon based on the chosen driving mode and on said second comparison and/or the second predicted vehicle speed V_{pred_Tnew} in this simulation cycle s_j, so that the at least one reference value is within the range bounded by the second lower and upper limit values v_min and v_max; and

the control system configured to regulate the speed of the vehicle according to said at least one reference value.

2. The control system according to claim 1, wherein the second lower and upper limit values v_min and v_max are defined on the basis of the choice of driving mode.

3. The control system according to claim 1, wherein a further lower limit value v_min and upper limit value v_max2 are defined based on the choice of driving mode and are related to the at least one set speed v_set.

4. The control system according to claim 1, wherein the choice of driving mode decides how said at least one reference value is determined.

5. The control system according to claim 1, wherein said at least one reference value is a reference speed v_ref, and the mode choice defines a permissible acceleration and/or retardation of the vehicle.

6. The control system according to claim 1, wherein the mode choice defines a weighting parameter β

, which is used in evaluation of one or more cost functions when determining said at least one reference value.

7. The control system according to claim 6, wherein the calculation unit is configured to perform the simulations by calculating the cost for the second predicted vehicle speed v_{pred_Tnew} and/or a third predicted vehicle speed V_{pred_Tk+new} by use of at least one cost function J_Tnew, J_Tk+new.

8. The control system according to claim 7, wherein the calculation unit is configured to determine the cost functions J_Tnew and J_Tk+new for the second predicted vehicle speed v_{pred_Tnew} and a third predicted vehicle speed v_{pred_Tk+new} by weighting with the weighting parameter β

, respectively, their energy reductions and journey time reductions relative to the first predicted vehicle speed V_{pred_cc}.

9. The control system according to claim 8, wherein the calculation unit is configured to compare, as a fourth comparison, the cost functions J_Tnew and J_Tk+new for the second predicted vehicle speed V_{pred_Tnew} and for a third predicted vehicle speed v_{pred_Tk+new},

wherein the determination of the at least one is based on said fourth comparison.

10. A method for determination of at least one reference value for a control system of a vehicle, wherein the method comprises:

acquiring a set speed v_set for the vehicle;

receiving a choice from at least two selectable driving modes, each driving mode comprising a setting which influences the determination of the at least one reference value;

determining for the itinerary, by reference to map data and location data, a horizon made up of at least one route segment with at least one characteristic;

performing, by a module incorporating an automated processor, a number of simulation cycles, each simulation cycle s_j, comprising a number N of simulation steps conducted at a predetermined rate f, the simulation steps comprising;

making a first prediction of the speed V_{pred_cc} of the vehicle along the horizon according to a conventional cruise control when the set speed v_set is imparted as a reference speed v_ref, the first prediction depending on the at least one characteristic of the route segment;

comparing, as a first comparison, the first predicted vehicle speed v_{pred_cc} with at least one of first lower and upper limit values v_lim1 and v_lim2, wherein the first lower and upper limit values v_lim1 and v_lim2 define an engine torque T for use in an immediately following simulation cycle s_j+1;

making a second prediction of the vehicle'"'"'s speed V_{pred_Tnew} along the horizon when the vehicle'"'"'s engine torque T is a value which depends on the result of said first comparison in an immediately preceding simulation cycle s<sub>j−

1</sub>;

comparing, as a second comparison, the second predicted vehicle speed V_{pred_Tnew} with at least one of second lower and upper limit values v_min and v_max, wherein the second lower and upper limit values v_min and v_max delineate a range within which the speed of the vehicle is maintained;

determining the at least one reference value based on said mode choice and on said second comparison and/or the second predicted vehicle speed V_{pred_Tnew} in this simulation cycle s_j, such that the at least one reference value is within a range bounded by the second lower and upper limit values v_min and v_max; and

regulating, by a control system of the vehicle, based on said at least one reference value, the speed of the vehicle.

11. A method according to claim 10, wherein the second lower and upper limit values v_min and v_max are defined based on the choice of driving mode.

12. A method according to claim 10, wherein a further lower limit value v_min2 and upper limit value v_max2 are defined based on the choice of driving mode and based on the set speed v_set.

13. A method according to claim 10, wherein the choice of driving mode decides how said at least one reference value is determined.

14. A method according to claim 10, wherein, when said at least one reference value is a reference speed v_ref, the mode choice defines a permissible acceleration and/or retardation of the vehicle.

15. A method according to claim 10, wherein the mode choice defines a weighting parameter β

, the weighting parameter β

used in evaluation of one or more cost functions when determining said at least one reference value.

16. A method according to claim 15, wherein the simulations are performed by calculating the cost for the second predicted vehicle speed V_{pred_Tnew} and/or a third predicted vehicle speed V_{pred_Tk+new} by use of at least one cost function J_Tnew, J_Tk+new.

17. A method according to claim 16, wherein the respective cost functions J_Tnew and J_Tk+new are determined for the second predicted vehicle speed v_{pred_Tnew} and a third predicted vehicle speed V_{pred_Tk+new} by weighting with the weighting parameter β

, respectively, energy reductions and journey time reductions relative to the first predicted vehicle speed V_{pred_cc}.

18. A method according to claim 17, further comprising, comparing, as a fourth comparison, the cost functions J_Tnew and J_Tk+new for the second predicted vehicle speed V_{pred_Tnew} and for a third predicted vehicle speed V_{pred_Tk+new}, wherein the at least one reference value is determined based on said fourth comparison.

19. A non-transitory computer-readable medium product comprising instructions configured to enable a computer of a vehicle to perform, when the instructions are run on said computer, a method comprising:

acquiring a set speed v_set for the vehicle;

receiving a choice from at least two selectable driving modes, each driving mode comprising a setting which influences the determination of the at least one reference value;

determining for the itinerary, by reference to map data and location data, a horizon made up of at least one route segment with at least one characteristic;

performing, by a module incorporating an automated processor, a number of simulation cycles, each simulation cycle s_j, comprising a number N of simulation steps conducted at a predetermined rate f, the simulation steps comprising;

making a first prediction of the speed v_{pred_cc} of the vehicle along the horizon according to a conventional cruise control when the set speed v_set is imparted as a reference speed v_ref, the first prediction depending on the at least one characteristic of the route segment;

comparing, as a first comparison, the first predicted vehicle speed v_{pred_cc} with at least one of first lower and upper limit values v_lim1 and v_lim2, wherein the first lower and upper limit values v_lim1 and v_lim2 define an engine torque T for use in an immediately following simulation cycle s_j+1;

making a second prediction of the vehicle'"'"'s speed V_{pred_Tnew} along the horizon when the vehicle'"'"'s engine torque T is a value which depends on the result of said first comparison in an immediately preceding simulation cycle s<sub>j−

1</sub>;

comparing, as a second comparison, the second predicted vehicle speed V_{pred_Tnew} with at least one of second lower and upper limit values v_min and v_max, wherein the second lower and upper limit values v_min and v_max delineate a range within which the speed of the vehicle is maintained; and

determining the at least one reference value based on said mode choice and on said second comparison and/or the second predicted vehicle speed v_{pred_Tnew} in this simulation cycle s_j, such that the at least one reference value is within a range bounded by the second lower and upper limit values v_min and v_max,

wherein a control system of the vehicle regulates a speed of the vehicle based on said at least one reference value.

20. A vehicle comprising a control system configured to determine at least one reference value for controlling a speed of the vehicle, the control system comprising:

a set speed input unit configured to receive at least one set speed v_set for the vehicle;

a mode choice receiving unit configured to receive a choice from at least two selectable driving modes, each driving mode comprising a setting which influences the determination of the at least one reference value;

a map data and location data-based horizon unit configured to determine an itinerary by reference to map data and location data, the horizon made up of at least one route segment with at least one characteristic;

a simulation cycle calculation unit configured to perform a number of simulation cycles s_j, each simulation cycle comprising a number N of simulation steps conducted at a predetermined rate f, the simulation steps including;

making a first prediction of the speed V_{pred_cc} of the vehicle along the horizon such that the set speed v_set is taken as a reference speed v_ref, the first prediction made based on the characteristic of said route segment;

comparing, as a first comparison, the first predicted vehicle speed v_{pred_cc} with w first lower and upper limit values v_lim1 and v_lim2 to define an engine torque T, the engine torque T used in an immediately following simulation cycle s_j+1;

making a second prediction of the speed v_{pred_Tnew} of the vehicle along the horizon, the engine torque T being a value defined in said first comparison in an immediately preceding simulation cycle s<sub>j−

1</sub>;

comparing, as a second comparison, the second predicted vehicle speed v_{pred_Tnew} with at least one of second lower and upper limit values v_min and v_max, wherein v_min and v_max delineate a range within which the speed of the vehicle is maintained;

determining said at least one reference value along the horizon based on the chosen driving mode and on said second comparison and/or the second predicted vehicle speed v_{pred_Tnew} in this simulation cycle s_j, so that the at least one reference value is within the range bounded by the second lower and upper limit values v_min and v_max; and

the control system configured to regulate the speed of the vehicle according to said at least one reference value.