A METHOD FOR CONTROLLING A DRIVELINE OF A VEHICLE

Abstract

The present disclosure relates to a method for controlling a driveline of a vehicle, the driveline being operable in a plurality of driveline operating modes, wherein the driveline is configured to assume a current driveline operating mode basing its operation on topology data from a positioning system, each driveline operating mode being associated with a predefined driveline operating condition, wherein the method comprises obtaining a signal indicative of a loss of topology data; and controlling the driveline to change from the current driveline operating mode to an updated driveline operating mode providing an increased operational capacity of the driveline compared to the current driveline operating mode.

Claims

1. A method for controlling a driveline of a vehicle, the driveline being operable in a plurality of driveline operating modes, wherein the driveline is configured to assume a current driveline operating mode basing its operation on topology data from a positioning system, each driveline operating mode being associated with a predefined driveline operating condition, the method being characterized by: obtaining a signal indicative of a loss of topology data; and controlling the driveline to change from the current driveline operating mode to an updated driveline operating mode providing an increased operational capacity of the driveline compared to the current driveline operating mode when loosing topology data.

2. The method according to claim 1, wherein the updated driveline operating mode comprises a transmission gear state with increased transmission gear ratio compared to the transmission gear ratio of the current driveline operating mode, in order to provide the increased operational capacity.

3. The method according to claim 1, wherein, for a prime mover of the driveline, a rotational speed for changing to a higher level transmission gear state of a transmission of the driveline is higher when assuming the updated driveline operating mode compared to when assuming the current driveline operating mode, in order to provide increased operational capacity.

4. The method according to claim 1, wherein a torque level for changing to a higher level transmission gear state of a transmission of the driveline is higher when assuming the updated driveline operating mode compared to when assuming the current driveline operating mode.

5. The method according to claim 1, wherein the method further comprises: obtaining, prior to the loss of topology data, a signal indicative of an upcoming road path for the vehicle, the upcoming road path comprising an upward slope portion; and controlling the driveline to change to the updated driveline operating mode based on an inclination of the upward slope portion.

6. The method according to claim 1, wherein the driveline is controlled to assume the updated driveline operating mode when a vehicle speed is below a predetermined threshold speed.

7. The method according to claim 6, wherein the threshold speed is in a range between 20-45 kmph.

8. The method according to claim 1, wherein the positioning system is at least one of a GPS, a GNSS or a LIDAR system.

9. The method according to claim 1, wherein the signal indicative of loss of topology data is a signal indicative of loss of topology data for an upcoming road path for the vehicle.

10. The method according to claim 1, further comprising: obtaining a signal indicative of re-established topology data; and controlling the driveline to change from the updated driveline operating mode to the driveline operating mode assumed prior to the loss of topology data.

11. The method according to claim 1, further comprising: obtaining a signal indicative of re-established topology data; and controlling the driveline to change from the updated driveline operating mode to a driveline operating mode based on the re-established topology data.

12. The method according to any one of the preceding claims, further comprising: upon obtaining the signal indicative of loss of location, transmitting a control signal to an operator of the vehicle, the control signal comprising an operator request demand to approve the change from the current driveline operating mode to the updated driveline operating mode; and controlling the driveline to assume the updated driveline operating mode when the operator request demand has been approved by the operator.

13. A control system connectable to a driveline of a vehicle, the control system comprising a positioning system and driveline mode selection module, wherein the driveline mode selection module is configured to select between a plurality of driveline operating modes based on topology data received from the positioning system, characterized in that the control system comprises control circuitry configured to: receive a signal from the positioning system, the signal being indicative of a loss of topology data; and control the driveline mode selection module to change from a current driveline operating mode to an updated driveline operating mode providing an increased operational capacity of the driveline compared to the current driveline operating mode when loosing topology data.

14. The control system according to claim 13, wherein the driveline comprises a prime mover and a transmission for gear selection.

15. A vehicle comprising a driveline controlled by a control system according to claim 13.

16. A vehicle according to claim 15, wherein the vehicle is an autonomously controlled vehicle.

17. A computer program comprising program code operative to receiving data from a positioning system to perform the steps of claim 1 when the program is run on a computer.

18. A computer readable medium carrying a computer program comprising program code operative to receiving data from a positioning system to perform the steps of claim 1 when the program code is run on a computer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The above, as well as additional objects, features and advantages, will be better understood through the following illustrative and non-limiting detailed description of exemplary embodiments, wherein:

[0038] FIG. 1 is a perspective view illustrating a vehicle, here in the form of a truck, according to an example embodiment;

[0039] FIG. 2 illustrates the vehicle in FIG. 1 during operation at an uphill slope according to an example embodiment;

[0040] FIG. 3 is a schematic illustration of a control system according to an example embodiment; and

[0041] FIG. 4 is a flow chart of a method for controlling a driveline of the vehicle in FIG. 1 according to an example embodiment.

DETAILED DESCRIPTION

[0042] The present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. The disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness. Like reference character refer to like elements throughout the description.

[0043] With particular reference to FIG. 1a, there is provided a vehicle 100 in the form of a truck. The vehicle 100 comprises a driveline 102 configured to be controlled by means of the control system and method described below. The driveline 102 comprising an engine 104 and a transmission 106 forming part of a gearbox. The engine 104 may be an internal combustion engine or an engine in the form of an electric machine. The vehicle 100 further comprises a control system 200 which is described in further detail below with reference to FIG. 3.

[0044] In order to describe the operational functionality of the vehicle according to an example embodiment of the present disclosure, reference is made to FIG. 2. FIG. 2 illustrates the vehicle in FIG. 1 during operation at a road path comprising an uphill slope 210 according to an example embodiment. The vehicle 100 is configured to assume a current driveline operating mode basing its operation on topology data from a positioning system 202 (illustrated in further detail in FIG. 3). The topology data is in the embodiment of FIG. 2 received from a shared data storage 300 in the form of a satellite which is in wireless communication with the positioning system 202.

[0045] The road path in FIG. 2 is exemplified as divided into six different road segments 1-6. The following will now describe example embodiments of different operating modes assumed by the driveline when operated at the road path 210 and receives map data from the shared data storage 300.

[0046] During operation at the first segment 1, the driveline assumes a driveline operating mode in which the vehicle accelerates to improve the initial hill climbing capacity. Thus, the vehicle driveline operating mode comprises increased acceleration, whereby the rpm of the engine is allowed to be relatively high before an upshift procedure is executed.

[0047] At the second segment 2, the driveline operating mode is set to avoid downshifting. Hereby, the fuel consumption is improved compared to operation at a lower gear stage. At the third segment 3, the vehicle 100 has reached the top of the hill, whereby the driveline assumes a driveline operating mode in which the vehicle speed is initially increasing before arriving at the downhill slope of the fourth segment 4. At the fourth segment 4, the driveline assumes a driveline operating mode in which the transmission is set in neutral position and the vehicle rolls freely towards the fifth segment 5.

[0048] At the fifth segment 5, the driveline assumes a driveline operating mode in which the engine 104 is controlled to perform engine braking. Hereby, over-speeding is avoided, and regenerative braking can be executed to, for example, charge a vehicle battery. At the final sixth segment 6, the driveline assumes a driveline operating mode in which the vehicle builds up speed in neutral gear of the transmission, thus preparing for further operation once leaving the sixth segment 6.

[0049] By means of the operation through these six segments 1-6 when map data is available, the utilization of the vehicle's kinetic energy is substantially optimized.

[0050] However, if the topology data is determined to be lost during operation, in particular during operation at the first 1 and/or second 2 segments, the driveline is controlled in a different manner compared to the above description, in order to avoid that the vehicle will involuntarily stop at the first or second segments. Reference is made to FIG. 2, in combination with FIG. 3 for describing in further details an example embodiment of controlling the driveline when the topology data is lost.

[0051] FIG. 3 is a schematic illustration of a control system 200 according to an example embodiment. The control system 200 comprises control circuitry that may include a microprocessor, microcontroller, programmable digital signal processor or another programmable device. The processing circuitry may also, or instead, each include an application specific integrated circuit, a programmable gate array or programmable array logic, a programmable logic device, or a digital signal processor. Where the control circuitry includes a programmable device such as the microprocessor, microcontroller or programmable digital signal processor mentioned above, the processor may further include computer executable code that controls operation of the programmable device. It should be understood that all or some parts of the functionality provided by means of the control circuitry (or generally discussed as processing circuitry) may be at least partly integrated with the control unit 200.

[0052] Furthermore, the control unit 200 comprises a positioning system 202, which is preferably a GNSS, such as a GPS. The positioning system 202 can also be a LIDAR system, or similar. The control unit 200 further comprises a driveline mode selection module 350. The positioning system 202 is configured to receive topology data from the shared data storage 300. The topology data is transmitted to the driveline mode selection module 350 which determines, based on the topology data, a driveline operating mode for optimally controlling the driveline. The driveline mode selection module 350 is connected to the driveline 102 and configured to control the operation of the driveline 102.

[0053] When the vehicle 100 is operated, as exemplified in FIG. 2, and the signal between the shared data storage 300 and the positioning system 202 is lost, as indicated by reference numeral 330, a signal indicative of loss of topology data is received by the driveline mode selection module 350. In order to maintain well-functioning drivability, the driveline mode selection module 350 changes from a current driveline operating mode to an updated driveline operating mode. The change to the updated driveline operating mode is executed for providing an increased operational capacity of the driveline 102 compared to the current driveline operating mode. An operator of the vehicle may, according to a non-limiting example, be required to provide an operator request demand to the driveline mode selection module 350 for approving the change from the current driveline operating mode to the updated driveline operating mode.

[0054] According to an example embodiment, the updated driveline operating mode may comprise a change of transmission gear state of the transmission 106, where the transmission is changed to a lower gear state. The updated driveline operating mode may also, as an option or in addition to the gear change, comprise a higher rotational speed and/or higher engine torque for upshifting to a higher gear state compared to the current driveline operating mode assumed when receiving the topology data. In this case, the change from a current gear state to a higher gear state is executed at higher rotational speed/engine torque compared to a normal operating condition.

[0055] When determining a specific updated driveline operating mode, the driveline mode selection module 350 may have received data beforehand of e.g. an inclination of the road path ahead, and can thus decide a suitable updated driveline operating mode for being able to sufficiently operate the vehicle at the slope in case of a loss of topology data. In detail, the driveline mode selection module 350 can receive topology data from the positioning system 202 indicative of the inclination of the first 1 and/or second 2 road segment depicted in FIG. 2.

[0056] Furthermore, in order to prevent e.g. downshifting of the transmission at higher vehicle speeds, which could result in an uncomfortable driving experience, the driveline mode selection module 350 may be configured to only control the driveline in the updated driveline operating mode when the vehicle speed is below a predetermined threshold speed, such as in the range between 20-45 kmph.

[0057] When the positioning system 202 re-establish topology data from the shared data storage 300, the driveline mode selection module 350 may change back to the driveline operating mode assumed prior to the loss of topology data, or change to a new driveline operating mode based on the current topology of the road path.

[0058] In order to sum up, reference is made to FIG. 4 which is a flow chart of the method of controlling the driveline 102 of the vehicle. As described above, a signal is obtained S1 by the positioning system 202, which signal is indicative of loss of topology data 330. Thus, the positioning system 202 fails to receive topology data from the shared data storage 300. When the loss of topology data is determined, the driveline mode selection module 350 controls the driveline 102 to change from the current driveline operating mode to the updated driveline operating mode providing an increased operational capacity of the driveline compared to the current driveline operating mode.

[0059] It is to be understood that the present disclosure is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.