METHOD FOR ADJUSTING AN AUTO-BRAKING SYSTEM OVERRIDE THRESHOLD

Abstract

A method of operating an auto-braking system of a vehicle in coordination with operation of a speed limiting system (SLS) of the vehicle to prevent undesired loss of auto-braking functionality. If: a) a driver input of an engine power control parameter (such as throttle setting) exceeds an activation threshold of the SLS so that the SLS is therefore limiting vehicle speed to a set-speed corresponding to the activation threshold; and b) the driver input of the power control parameter is below a SLS override threshold; and c) the SLS override threshold exceeds an auto-braking override threshold for the power control parameter; then the auto-braking override threshold is increased to at least equal the SLS override threshold. The speed limiter activation threshold may be determined from speed limit information supplied by a vehicle navigation system of by an image evaluating unit from images obtained by a camera of the vehicle

Claims

1. A method of operating an auto-braking system of a vehicle comprising: determining that a driver input of a power control parameter exceeds an activation threshold of a vehicle speed limiter system (SLS), and the SLS is therefore limiting vehicle speed to a set-speed corresponding to the activation threshold; determining that the driver input of the power control parameter is below a SLS override threshold; determining that the SLS override threshold exceeds an auto-braking override threshold for the power control parameter; and in reaction to the above determinations, increasing the auto-braking override threshold to at least equal the SLS override threshold.

2. The method of claim 1, wherein the power control parameter is a throttle setting of a vehicle engine.

3. The method of claim 1, further comprising adjusting the speed limiter activation threshold in dependence upon speed limit information for a location of the vehicle supplied by a vehicle navigation system.

4. The method of claim 1, further comprising adjusting the speed limiter activation threshold in dependence upon speed limit information for a location of the vehicle supplied by an image evaluating unit from images obtained by a camera of the vehicle.

5. A method of operating an auto-braking system of a vehicle comprising: determining that a driver input of a power control parameter exceeds a vehicle speed limiter system (SLS) activation threshold and is below a SLS override threshold; determining that the SLS override threshold exceeds an auto-braking override threshold for the power control parameter; and in reaction to the above determinations, increasing the auto-braking override threshold to at least equal the SLS override threshold.

6. The method of claim 5, wherein the power control parameter is a setting of a throttle of a vehicle engine.

7. The method of claim 5, further comprising adjusting the speed limiter activation threshold in dependence upon speed limit information for a location of the vehicle supplied by a vehicle navigation system.

8. The method of claim 5, further comprising adjusting the speed limiter activation threshold in dependence upon speed limit information for a location of the vehicle supplied by an image evaluating unit from images obtained by a camera of the vehicle.

9. A method of operating an auto-braking system comprising: determining that a) a driver throttle input exceeds a vehicle speed limiter system (SLS) activation throttle setting and is below a SLS override threshold, and b) the SLS override threshold exceeds an auto-braking override threshold; and in reaction to a) and b) above, increasing the auto-braking override threshold to at least equal the SLS override threshold.

10. The method of claim 9, further comprising adjusting the speed limiter activation threshold in dependence upon speed limit information for a location of the vehicle supplied by a vehicle navigation system.

11. The method of claim 9, further comprising adjusting the speed limiter activation threshold in dependence upon speed limit information for a location of the vehicle supplied by an image evaluating unit from images obtained by a camera of the vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG. 1 illustrates schematically a vehicle in accordance with a disclosed embodiment of the invention having an auto-braking system that can be adaptively overridden in an exemplary embodiment; and

[0040] FIG. 2 illustrates schematically a method in accordance with a disclosed embodiment of the invention for adjusting an auto-braking override threshold value for a vehicle in an exemplary embodiment.

DETAILED DESCRIPTION

[0041] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

[0042] In the figures, identical or similar elements are provided with identical reference numerals provided this is expedient.

[0043] FIG. 1 illustrates schematically a vehicle in accordance with the invention having an auto-braking system that can be adaptively overridden in an exemplary embodiment. The vehicle 10 comprises an engine 12 and the wheels 11 of the vehicle 10 can be driven using the power output of said engine. This is illustrated in FIG. 1 by means of arrows to two of the four wheels 11. In other embodiments, it is also possible to drive more or fewer wheels by means of the engine 12.

[0044] Moreover, the vehicle 10 comprises an auto-braking system 13 that is designed and operative to autonomously implement a braking procedure or intervention and that can be deactivated when a vehicle driver makes an input to a control parameter of a power output of the engine that exceed an auto-braking override threshold value (Limit E.sub.OD). FIG. 1 illustrates using arrows that the auto-braking system acts upon the brakes of two of the four wheels 11. In another embodiment, the automatic auto-braking system acts upon more or fewer than two wheels 11.

[0045] The vehicle 10 further comprises a speed limiter system 14 that is designed and operative to limit a speed of the vehicle 10 and that can be deactivated when a speed limiter override threshold value (Limit V.sub.OD) of the control parameter is exceeded.

[0046] The auto-braking system 13 is configured and operative to change the auto-braking override threshold value to at least the speed limiter override threshold value if the speed limiter system 14 is active in that it is actively limiting a speed of the vehicle 10. The auto-braking system 13 comprises an electronic programmable device or controller 15 operative to evaluate the data of the auto-braking system and state data that is received by the speed limiter system (these data inputs described in further detail below) and to adjust the auto-braking override threshold.

[0047] In the embodiment illustrated in FIG. 1, the vehicle 10 comprises a throttle which may be implemented as a pedal 16 for controlling the power output of the engine, and the control parameter is a travel of the pedal 16 relative to a) a first position of the pedal 16, said first pedal position corresponding to a minimum effect on the power output of the engine 12 or to b) a second position of the pedal 16, said second position at least when not in the active operating state of the speed limiter system 14 corresponding to a maximum increasing effect on the power output of the engine 12. If the position of the pedal 16 is ascertained using a pedal position sensor 17, the measured sensor values of said pedal position sensor are transferred to the auto-braking system 13 and the speed limiter system 14. The effect of the pedal 16 on the power output of the engine 12 is illustrated in a greatly simplified manner using a connecting arrow without illustrating the further components that are involved and that in the case of a motor vehicle having an internal combustion engine include by way of example inter alia also a fuel pump, a carburetor, a drive-train and a transmission.

[0048] In the embodiment illustrated in FIG. 1 the vehicle 10 further comprises a navigation system 18. The speed limiter system 14 receives speed limit information (recommended and/or regulatory) therefrom, said information being related to the environment or location of the vehicle 10 at a particular time, and is configured and operative to adjust the speed limiter activating threshold value in dependence upon this speed limiter information.

[0049] FIG. 2 illustrates schematically an associated method 20 in accordance with the invention for adjusting an auto-braking override threshold value for a vehicle in an exemplary embodiment, wherein the vehicle (as illustrated by way of example in FIG. 1) comprises at least one engine, an auto-braking system designed to autonomously implement an auto-braking procedure and that can be deactivated when an auto-braking override threshold (Limit E.sub.OD) of a control parameter of a power output of the engine that can be changed by a driver of the vehicle is exceeded, and a speed limiter system designed and operative to limit a speed of the vehicle and that can be deactivated when a speed limiter override threshold (Limit V.sub.OD) of the control parameter is exceeded.

[0050] The method 10 comprises monitoring 22 the operating state of the speed limiter system after a start 21. If the monitoring procedure 22 establishes that the speed limiter system is not limiting the speed (V) of the vehicle (step 22, NO), the monitoring procedure is continued.

[0051] However, if the monitoring procedure of step 22 establishes that the current value (V) of the control parameter being input (or demanded) by the driver exceeds an activating threshold value (V.sub.active) of the control parameter (step 22, YES), the method progresses to step 23. In the described example wherein throttle pedal travel is the control parameter of engine power output, the condition V>V.sub.active equates to a situation wherein the driver's throttle input/demand exceeds the throttle position corresponding to the set-speed established by the speed limiting system, and therefore the speed limiting system is actively limiting the speed of the vehicle and the vehicle speed does not increase beyond the set-speed regardless of further throttle travel.

[0052] At step 23, a comparison check is made as to whether the current speed limiter override threshold value (Limit V.sub.OD ) exceeds the auto-braking override threshold (Limit E.sub.OD). If YES, the method progresses to step 24 where the auto-braking override threshold (Limit E.sub.OS) is increased to a level at least equal to the speed limiter override threshold value (Limit V.sub.OD). In the illustrated embodiment, the auto-braking override threshold is increased to be equal to the speed limiter override threshold (Limit E.sub.OD=Limit V.sub.OD).

[0053] The comparison of the speed limiter override threshold value (Limit V.sub.OD) with the auto-braking override threshold value (Limit E.sub.OD) at step 23 ensures that the auto-braking override threshold value (Limit E.sub.OD) will only be only be increased (never decreased) in value. If this applies the adjustment is performed, otherwise (step 23, NO) the method is continued with the procedure of monitoring the activating state.

[0054] It is further provided that the method is terminated in the event of the vehicle being deactivated (ignition switched off, for example) or also the speed limiter system and/or the auto-braking system being switched off (by a manual switch actuation or other driver command, for example, since if none of or only one of the two systems are activated, it is not possible for conflict to occur when the systems are being overridden.

[0055] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.