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EP-4488133-B1 - PROPULSION TORQUE CONTROL DURING BRAKE-RELEASE IN A VEHICLE

EP4488133B1EP 4488133 B1EP4488133 B1EP 4488133B1EP-4488133-B1

Inventors

  • SUBRAMANIAN, CHIDAMBARAM
  • PEDDYCORD, Jeffrey

Dates

Publication Date
20260513
Application Date
20230706

Claims (14)

  1. A controller (120, 400, 600) for a vehicle (110), configured to: - determine a take-off intent, and - in response to determining the take-off intent: i) initiate a release of a brake (142, 144) for at least one wheel (180a-c) or wheel axle (182a-c) of the vehicle, and ii) inhibit an application of propulsion torque to the at least one wheel or wheel axle during a finite time period (TR) related to a time required for releasing the brake, characterized in that the controller is further configured to determine and/or update a value of the finite time period using a reinforcement learning model (170) trained to determine and/or update the value of the finite time period based on data (146, 164, 172) indicative of vehicle brake wear and/or clutch wear during take-off.
  2. The controller according to claim 1, further configured to determine the take-off intent while the brake is applied.
  3. The controller according to claim 1 or 2, wherein to determine the take-off intent comprises at least one of: - to detect a depressing of a throttle pedal (131b) of the vehicle and/or an engagement or shifting of a transmission (132b) of the vehicle; - to detect a closing of a door (134b) of the vehicle, and - to detect a fastening of a seatbelt (133b) of the vehicle;
  4. The controller according to any one of the preceding claims, further configured to, before determining the take-off intent, apply the brake in response to determining an intent of a driver or passenger of the vehicle to leave the vehicle.
  5. The controller according to claim 4, wherein to determine the intent of the driver or passenger to leave the vehicle comprises at least one of: - to detect a release of a throttle pedal (131b) of the vehicle and/or a disengagement or shifting of a transmission (132b) of the vehicle; - to detect a releasing of a seatbelt (133b) of the vehicle; - to detect an opening of a door (134b) of the vehicle, and - to detect an imminent stopping of the vehicle.
  6. The controller according to any one of the preceding claims, further configured to: - in response to a lapsing of the finite time period, end said inhibiting of the application of propulsion torque.
  7. The controller according to claim 1, wherein the reinforcement learning model is implemented in said controller and configured to increase the finite time period in response to determining that, as an indication of brake wear, the vehicle is moving even though the at least one wheel or wheel axle is not rotating.
  8. The controller according to claim 1 or 7, wherein the reinforcement learning model is implemented in the controller and configured to increase the finite time period in response to determining that, as an indication of clutch wear, the vehicle is not moving even though propulsion torque is being applied to a clutch connected to the at least one wheel or wheel axle.
  9. The controller according to any one of the preceding claims, wherein to initiate the release of the brake and inhibit the application of propulsion torque is performed sufficiently simultaneously or concurrently to avoid any propulsion torque from being applied to the at least one wheel or wheel axle while the brake is still applied.
  10. An automated brake-release system (100) for a vehicle (110), comprising: - a brake (142, 144) for braking of at least one wheel (180a-c) or wheel axle (182a-c) of the vehicle, and - a controller (120, 400, 600) according to any one of the preceding claims.
  11. A vehicle (110) comprising the controller (120, 400, 600) according to any one of claims 1 to 10 or the automated brake-release system (100) according to claim 10.
  12. A method (200) performed in a controller (120) of a vehicle (110), comprising: - determining (S202) a take-off intent, and - in response to determining the take-off intent: i) initiating (S204) a release of a brake (142, 144) for at least one wheel (180a-c) or wheel axle (182a-c) of the vehicle, and ii) inhibiting (S206) an application of propulsion torque to the at least one wheel or wheel axle during a finite time period (TR) related to a time required for releasing the brake, characterized in that the method further comprises determining and/or updating a value of the finite time period by using a reinforcement learning model (170) trained to determine and/or update the value of the finite time period based on data (146, 164, 172) indicative of vehicle brake wear and/or clutch wear during take-off.
  13. A computer program product (510) comprising program code (520) which, when executed by processing circuitry (410) of a controller (120, 400, 600) of a vehicle, causes the controller to perform the method (200) according to claim 12.
  14. A non-transitory computer-readable storage medium (420, 530) comprising instructions which, when executed by processing circuitry (410) of a controller (120, 400, 600) of a vehicle (110), causes the controller to perform the method (200) according to claim 12.

Description

TECHNICAL FIELD The invention relates generally to braking of vehicles. In particular aspects, the invention relates to propulsion torque control during (automated) brake-release in a vehicle. The invention can be applied to heavy-duty vehicles, such as trucks, buses, and construction equipment, among other vehicle types. Although the invention may be described with respect to a particular vehicle, the invention is not restricted to any particular vehicle. BACKGROUND Contemporary vehicles, such as e.g. various heavy or semi-heavy vehicles, may be equipped with a system which automatically engages a brake in order to prevent the vehicle from rolling away once stopped or parked. For example, there are systems that may detect that the vehicle has come to a halt, and which in response thereto may automatically engage a parking or service brake of the vehicle. For vehicles which tend to go through multiple stop-and-go operations each day, such as e.g. garbage trucks, delivery trucks, busses, or similar, this may be particularly beneficial as it reduces the risk of an accidental roll-away caused by the driver haven forgotten to activate e.g. a parking brake before leaving the vehicle cabin. Likewise, there are also such systems available which, in addition to automatically applying the brakes, may also detect that the driver depresses a throttle pedal of the vehicle (or shows any other form of take-off intent) once having returned to the cabin, and which may then automatically also release the (automatically) applied brake in response thereto. WO 2022/136597 A1 discloses a control method for automatic holding of a vehicle, in which a drive-off signal is outputted to a drive motor controller to avoid providing drive torque until a driver requested drive torque increases to a critical torque which is close to an effective brake torque. The present invention seeks to develop the available such automated brake-release technology further and to mitigate one or more shortcomings thereof. SUMMARY As the inventor has realized, one shortcoming of contemporary systems for automatically applying and releasing e.g. a parking brake is that the systems are often based on open-loop control, which provides no guarantee that propulsion torque is not applied to the wheels while the brakes are still engaged. Often, this is caused by the release of the brake being a slower process than that of applying propulsion torque. Using a garbage truck as an example of such a vehicle, performing hundreds of stop-and-go operations a day may thus cause excessive wear to the vehicle's powertrain and/or brakes over time if, for each such stop-and-go operation, there is at least some time during which both braking torque and propulsion torque are concurrently applied to the wheels of the vehicle. In order to improve on this situation, the present invention provides an improved controller for a vehicle, an automated brake-release system for a vehicle and including such a controller, a vehicle including such a controller or automated brake-release system, a method performed in such a controller, a computer program product and computer-readable storage medium as defined in and by the accompanying independent claims. Various alternatives of the improved controller, system, vehicle, method, computer program product and computer-readable storage medium are defined in and by the accompanying dependent claims. According to a first aspect of the present invention, there is provided a controller for (automated brake-release in) a vehicle. The controller is configured to determine a take-off intent. The controller is configured to, in response to determining the take-off intent, i) (automatically) initiate a release of a brake for at least one wheel or wheel axle of the vehicle, and ii) (automatically) inhibit an application of propulsion torque to the at least one wheel or wheel axle during a finite time period related to a time required for releasing the brake. The first aspect of the invention may seek to improve upon currently available technology by, while still implementing open-loop control which is cheaper and easier to implement than e.g. a closed-loop control relying on various sensor information (such as information about brake pressure or similar), reduce or even eliminate the risk of concurrent application of both propulsion and braking torque during take-off of the vehicle. By properly adjusting the finite time period, a technical benefit of the envisaged controller may include that it introduces a delay of the application of any propulsion torque until the brake has had time to be sufficiently or completely released, which can dramatically reduce the wear on the vehicle's drive train and/or brakes for vehicles which perform multiple stop-and-go operations during a day. As such wear may also, if left unattended, eventually cause failure of one or more parts of the vehicle, the envisaged controller thus also improves upon the overall vehicle saf