Method and control arrangement for controlling a brake system in a vehicle

1 . A method for a control arrangement configured to control a brake system in a vehicle, the vehicle comprising an auxiliary brake system configured to apply a brake force to at least one first wheel of the vehicle and a foundation brake system configured to apply a brake force to at least one second wheel of the vehicle, the method comprising, when a first brake force is or is to be applied to the vehicle by means of the auxiliary brake system and when an indication of an instability condition associated with a coming road section is detected:

initiating a transfer of at least a part of the first brake force applied to the vehicle by the auxiliary brake system to, instead, be applied by the foundation brake system prior to reaching the coming road section to overcome the detected instability condition,

wherein the initiating of the transfer of the brake force comprises controlling the auxiliary brake system to gradually reduce the applied first brake force while controlling the foundation brake system to apply a gradually increased brake force.

2 . A method according to claim 1 , wherein the instability condition is based on a vehicle operating parameter.

3 . A method according to claim 1 , wherein the auxiliary brake system is controlled to gradually reduce the applied first brake force to a second brake force such that the second brake force is applied prior to or when reaching the coming road section, the method further comprising prior to or when reaching the coming road section:

controlling the auxiliary brake system to apply the second brake force; and

controlling the foundation brake system to apply a brake force such that a total requested brake force is applied to the vehicle.

4 . A method according to claim 3 , wherein the foundation brake system is further configured to apply a brake force to the at least one first wheel.

5 . A method according to claim 3 , wherein the second brake force is based on one or more vehicle operating parameters and the detected instability condition.

6 . A method according to claim 1 , further comprising:

reducing the total requested brake force applied to the vehicle when the transfer of the at least a part of the first brake force applied to the vehicle by the auxiliary brake system is insufficient to overcome the detected instability condition.

7 . A method according to claim 1 , wherein the transfer of the at least a part of the first brake force is initiated at a distance to the coming road section, the distance being based on one or more vehicle operating parameters and the detected instability condition.

8 . A method according to claim 2 , wherein the vehicle operating parameters in the coming road section is one or more of:

an information related to the coming road section;

the first brake force; and/or

a configuration of the vehicle.

9 . A method according to claim 1 , wherein the initiating of the transfer of the at least a part of the first brake force comprises:

alerting the vehicle operator of the detected instability condition associated with the coming road section.

10 . A method according to claim 1 , further comprising when the instability condition is no longer present:

controlling the auxiliary brake system to increase the applied brake force while controlling the foundation brake system such that the total requested brake force is applied to the vehicle.

11 . A control arrangement configured to control a brake system in a vehicle, the vehicle comprising an auxiliary brake system configured to apply a brake force to at least one first wheel of the vehicle and a foundation brake system configured to apply a brake force to at least one second wheel of the vehicle, the control arrangement being configured to, when a first brake force is applied to the vehicle by means of the auxiliary brake system and when an indication of an instability condition associated with a coming road section is detected:

initiate a transfer of at least a part of the first brake force applied to the vehicle by the auxiliary brake system to, instead, be applied by the foundation brake system prior to reaching the coming road section,

wherein initiation of the transfer of the brake force comprises to control the auxiliary brake system to gradually reduce the applied first brake force while controlling the foundation brake system to apply a gradually increased brake force.

12 . A vehicle comprising a control arrangement,

configured to control a brake system in a vehicle, the vehicle comprising an auxiliary brake system configured to apply a brake force to at least one first wheel of the vehicle and a foundation brake system configured to apply a brake force to at least one second wheel of the vehicle, the control arrangement being configured to, when a first brake force is applied to the vehicle by means of the auxiliary brake system and when an indication of an instability condition associated with a coming road section is detected:

initiate a transfer of at least a part of the first brake force applied to the vehicle by the auxiliary brake system to, instead, be applied by the foundation brake system prior to reaching the coming road section,

wherein initiation of the transfer of the brake force comprises to control the auxiliary brake system to gradually reduce the applied first brake force while controlling the foundation brake system to apply a gradually increased brake force.

13 . Computer program product stored on a non-transitory computer-readable medium, said computer program product for controlling a brake system in a vehicle, the vehicle comprising an auxiliary brake system configured to apply a brake force to at least one first wheel of the vehicle and a foundation brake system configured to apply a brake force to at least one second wheel of the vehicle, wherein said computer program product comprising computer instructions to cause one or more control devices to perform the following operation when a first brake force is applied to the vehicle by means of the auxiliary brake system and when an indication of an instability condition associated with a coming road section is detected:

initiate a transfer of at least a part of the first brake force applied to the vehicle by the auxiliary brake system to, instead, be applied by the foundation brake system prior to reaching the coming road section,

wherein initiation of the transfer of the brake force comprises to control the auxiliary brake system to gradually reduce the applied first brake force while controlling the foundation brake system to apply a gradually increased brake force.

14 . The control arrangement according to claim 11 , wherein the instability condition is based on a vehicle operating parameter.

15 . The control arrangement according to claim 11 , wherein the auxiliary brake system is controlled to gradually reduce the applied first brake force to a second brake force such that the second brake force is applied prior to or when reaching the coming road section, the method further comprising prior to or when reaching the coming road section:

controlling the auxiliary brake system to apply the second brake force; and

controlling the foundation brake system to apply a brake force such that a total requested brake force is applied to the vehicle.

16 . The control arrangement according to claim 15 , wherein the foundation brake system is further configured to apply a brake force to the at least one first wheel.

17 . The control arrangement according to claim 15 , wherein the second brake force is based on one or more vehicle operating parameters and the detected instability condition.

18 . The control arrangement according to claim 11 , further comprising:

reducing the total requested brake force applied to the vehicle when the transfer of the at least a part of the first brake force applied to the vehicle by the auxiliary brake system is insufficient to overcome the detected instability condition.