Method and system for exiting a sailing mode of a vehicle

• US 9,333,972 B2
• Filed: 09/26/2014
• Issued: 05/10/2016
• Est. Priority Date: 09/26/2014
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Thein, Sebastian, Schirnhofer, Robert, Neumann, Lutz, Nell, Markus, Soller, Tobias
• Primary Examiner(s): Badii, Behrang
• Application Number:
  US14/498,020
• Publication Number:
  US 20160090093A1
• Time in Patent Office: 592 Days
• US Class Current: 1/1
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2030/18081 With torque flow from driveshaft to engine, i.e. engine being driven by vehicle
• CPC Class Codes: B60W 2030/1809 Without torque flow between driveshaft and engine, e.g. with clutch disengaged or transmission in neutral
• CPC Class Codes: B60W 2030/206 related or induced by the engine
• CPC Class Codes: B60W 2510/0208 Clutch engagement state, e.g. engaged or disengaged
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 30/18072 Coasting
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: Y02T 10/60 Other road transportation technologies with climate change mitigation effect

Abstract

A method (600) for exiting a sailing mode of a vehicle (100) is described. The vehicle (100) comprises a clutch unit (103) which is disengaged in order to decouple a driving shaft (102) of the vehicle (100) from a driven shaft (105) of the vehicle (100), when the vehicle (100) is operated in the sailing mode. The method (600) comprises predicting (601) that a trigger for an exit of the sailing mode will occur, and initiating (602) the preparation of the clutch unit (103) for engagement, subject to predicting that a trigger for the exit of the sailing mode will occur. Furthermore, the method (600) comprises detecting (603) a trigger for the exit of the sailing mode, and adapting (604) a shaft speed (230) of the driving shaft (102), subject to detecting a trigger for the exit of the sailing mode. In addition, the method (600) comprises engaging (605) the clutch unit (103), subject to preparing the clutch unit (103) for engagement and subject to adapting the shaft speed (130), in order to exit the sailing mode.

Claims

1. A method for exiting a sailing mode of a vehicle;

wherein a clutch unit of the vehicle is disengaged in order to decouple a driving shaft of the vehicle from a driven shaft of the vehicle, when the vehicle is operated in the sailing mode;

the method comprising

predicting that a trigger for an exit of the sailing mode will occur;

initiating the preparation of the clutch unit for engagement, subject to predicting that a trigger for the exit of the sailing mode will occur;

detecting a trigger for the exit of the sailing mode;

adapting a shaft speed of the driving shaft, subject to detecting a trigger for the exit of the sailing mode; and

engaging the clutch unit, subject to preparing the clutch unit for engagement and subject to adapting the shaft speed, in order to exit the sailing mode.

2. The method of claim 1, wherein a trigger for the exit of the sailing mode is predicted based on sensor data from one or more vehicle sensors.

3. The method of claim 2, wherein the one or more vehicle sensors comprise one or more of:

a throttle sensor configured to measure a degree of actuation of a throttle device for accelerating the vehicle; and

/or

a camera configured to capture image data of a driver of the vehicle; and

/or

a sensor configured to detect a foot of the driver which is approaching a throttle pedal of the vehicle.

4. The method of claim 1, wherein predicting that a trigger for the exit of the sailing mode will occur comprises detecting that a throttle device of the vehicle is actuated.

5. The method of claim 4, wherein predicting that a trigger for the exit of the sailing mode will occur comprises detecting that the throttle device reaches or exceeds a first throttle threshold;

wherein the first throttle threshold is smaller than a second throttle threshold used as a trigger for the exit of the sailing mode.

6. The method of claim 1, wherein

predicting that a trigger for the exit of the sailing mode will occur occurs at a first time instant;

detecting a trigger for the exit of the sailing mode occurs at a second time instant; and

the second time instant is subsequent to the first time instant.

7. The method of claim 1, wherein initiating the preparation of the clutch unit for engagement comprises inserting a liquid into the clutch unit to build up a hydraulic pressure for engagement of the clutch unit;

wherein the clutch unit is prepared for engagement once the hydraulic pressure is stabilized at an engagement pressure.

8. The method of claim 1, wherein detecting a trigger for the exit of the sailing mode comprises detecting that a throttle device of the vehicle reaches or exceeds a second throttle threshold.

9. The method of claim 1, wherein a preparation time for preparing the clutch unit for engagement is longer than an adaption time for adapting the shaft speed of the driving shaft.

10. The method of claim 1, wherein adapting the shaft speed comprises increasing the shaft speed up to a target speed;

wherein the target speed is dependent on a speed of the driven shaft.

11. The method of claim 1, further comprising

determining a time that has passed since a first time instant when it was predicted that a trigger for an exit of the sailing mode will occur;

and

aborting the preparation of the clutch unit, if the time that has passed since the first time instant is equal to or exceeds a pre-determined time interval, and if no trigger for the exit of the sailing mode has been detected since the first time instant.

12. The method of claim 1, wherein the clutch unit and a transmission of the vehicle form an automatic clutch/transmission unit.

13. The method of claim 1, wherein adapting the shaft speed of the driving shaft comprises

during a first adaption phase, regulating the shaft speed of the driving shaft in accordance to a target speed;

interrupting the regulation of the shaft speed prior to reaching the target speed and prior to engaging the clutch unit; and

subsequently, during a second adaption phase, adapting a torque at the driving shaft in accordance to a torque which is transmissible by the clutch unit prior to engagement of the clutch unit.

14. A control unit for a vehicle;

wherein the vehicle comprises a clutch unit which is disengaged, when the vehicle is operated in a sailing mode, in order to decouple a driving shaft of the vehicle from a driven shaft of the vehicle;

wherein the control unit is configured to

predict that a trigger for an exit of the sailing mode will occur;

initiate the preparation of the clutch unit for engagement, subject to predicting that a trigger for the exit of the sailing mode will occur;

detect a trigger for the exit of the sailing mode;

cause a shaft speed of the driving shaft to be adapted, subject to detecting a trigger for the exit of the sailing mode; and

cause the clutch unit to be engaged, subject to preparing the clutch unit for engagement and subject to adapting the shaft speed, in order to exit the sailing mode.