Adaptive speed controller for motor vehicles and method for adaptive speed control

Abstract

The invention concerns an adaptive speed controller for a motor vehicle, with a stop-and-go system for an automatic or driver-confirmed restart following a standstill of the motor vehicle because of a vehicle ahead coming to a standstill and starting again, wherein if the motor vehicle comes to a standstill the stop-and-go system then enters a dynamic standstill state (t.sub.0 to t.sub.1) from which an automatic dynamic restart is possible, and wherein a preset period of time after the motor vehicle has come to a standstill and remains therein, the stop-and-go system enters a confirmation standstill state (>t.sub.4) from which an automatic restart is only possible after a driver's confirmation. According to the invention, the confirmation standstill state (>t.sub.4) does not immediately follow the first standstill state (t.sub.0 to t.sub.1), but with the temporal interposition of an intermediate standstill state (t.sub.1 to t.sub.4), in which an automatic restart is possible, which differs from the dynamic standstill state by different measures such as additional driver instructions, limited acceleration or the insertion of crawling phases. As a result of this, the driver is made aware of the automatic restart even after a long time at a standstill.

Claims

1. A speed controller for a motor vehicle, the speed controller comprising: a stop-and-go system for automatic or driver-confirmed restarting after a standstill of the motor vehicle due to a vehicle ahead of the motor vehicle coming to a standstill and starting again, wherein when the motor vehicle comes to the standstill, the stop-and-go system is configured to enter a dynamic restarting state (t.sub.0 to t.sub.1) from which an automatic dynamic restart is possible, wherein after the motor vehicle has come to the standstill and remains therein for a preset period of time, the stop-and-go system is configured to enter a confirmation standstill state (>t.sub.4) from which an automatic restart is possible after a driver's confirmation, wherein the confirmation standstill state (>t.sub.4) does not immediately follow a dynamic standstill state (t.sub.0 to t.sub.1) but follows with an interposition in time of at least one intermediate standstill state (t.sub.1 to t.sub.4) in which the automatic restart is possible, and wherein the intermediate standstill state (t.sub.1 to t.sub.4) differs from the dynamic standstill state (t.sub.0 to t.sub.1) by the following measures configured to increase attentiveness and/or starting safety by: a) producing at least one starting instruction at a start and/or during a start up, wherein the at least one starting instruction comprises at least one of a visual, audible, and/or haptic instruction, and one or more of: b) starting with a lower acceleration of the motor vehicle than a maximum acceleration that is provided for a restart from the dynamic standstill state (t.sub.0 to t.sub.1); and c) starting with at least a temporary reduction of a speed of the motor vehicle compared to the restart from the dynamic standstill state (t.sub.0 to t.sub.1) in the form of at least one crawling phase.

2. The speed controller as claimed in claim 1, wherein a use and the intensity of the measures a) through c) are varied depending on a time taken to restart within the intermediate standstill state (t.sub.1 to t.sub.4) such that with increasing duration of the intermediate standstill state (t.sub.1 to t.sub.4) until the restart, increased attentiveness and/or starting safety are produced by the measures a) through c).

3. The speed controller as claimed in claim 2, wherein the intermediate standstill state (t.sub.1 to t.sub.4) is divided or cascaded into successive phases (t.sub.1 to t.sub.2, t.sub.2 to t.sub.3, t.sub.3 to t.sub.4), in each of which an automatic restart is possible, wherein the phases each differ in terms of a use and/or in terms of an intensity of the measures a) through c).

4. The speed controller as claimed in claim 3, wherein the intermediate standstill state is divided or cascaded into two or more phases, wherein: a first phase (t.sub.1 to t.sub.2) of the intermediate standstill state comprises at least one starting instruction and a start up with a lower acceleration than from the dynamic standstill state (t.sub.0 to t.sub.1); and a second phase (t.sub.1 to t.sub.2) of the intermediate standstill state, which starts after the first phase, comprises at least one start up with a lower acceleration than in the first phase and additionally comprises the at least one crawling phase, third phase (t.sub.3 to t.sub.4) of the intermediate standstill state, which starts after the second phase, comprises at least one additional starting instruction following the at least one crawling phase.

5. The speed controller as claimed in claim 4, wherein the stop-and-go system changes from the first phase of the intermediate standstill state (t.sub.1 to t.sub.2) to the second phase of the intermediate standstill state (t.sub.2 to t.sub.3) between 6 and 10 seconds after the motor vehicle has come to the standstill.

6. The speed controller as claimed in claim 4, wherein between 12 and 18 seconds after the motor vehicle has come to the standstill, the stop-and-go system changes from the second phase of the intermediate standstill state (t.sub.2 to t.sub.3) to the third phase of the intermediate standstill state (t.sub.3 to t.sub.4) and changes to the confirmation standstill state (>t.sub.4) between 5 and 10 seconds thereafter.

7. The speed controller as claimed in claim 4, wherein the at least one additional starting instruction comprises a haptically perceptible starting jolt.

8. The speed controller as claimed in claim 2, wherein the stop-and-go system changes from the dynamic standstill state (t.sub.0 to t.sub.1) to the intermediate standstill state (t.sub.1 to t.sub.4) between 2 and 4 seconds after the motor vehicle has come to the standstill.

9. The speed controller as claimed in claim 1, wherein the audible starting instruction comprises a sound signal and/or an audible accentuation of a starting jolt that is coordinated in time with said haptic starting jolt.

10. The speed controller as claimed in claim 1, wherein the motor vehicle comprises a visual display configured to display different symbols that indicate a corresponding standstill state and also distinguish whether the vehicle ahead of the motor vehicle is at a standstill or is starting up depending on whether the stop-and-go system is in the dynamic standstill state (t.sub.0 to t.sub.1) or in the confirmation standstill state (>t.sub.4) or in any standstill state (t.sub.1 to t.sub.2; t.sub.2 to t.sub.3; t.sub.3 to t.sub.4) that lie temporally in between.

11. The speed controller as claimed in claim 1, wherein the haptic instruction comprises a starting jolt that is configured to be perceptible by the driver of the motor vehicle.

12. A method for adaptive speed control for a motor vehicle as a function of a distance from a vehicle ahead of the motor vehicle measured with a distance sensor, wherein the motor vehicle is configured to automatically follows the vehicle ahead of the motor vehicle to a standstill and (i) automatically start again from the standstill if a time of the standstill (t) has not exceeded a specified period of time (t.sub.1−t.sub.0) or (ii) automatically starts again following confirmation by a driver of the motor vehicle, the method comprising: taking, if the time of the standstill (t) has exceeded the specified period of time (t.sub.1−t.sub.0) and the vehicle ahead of the motor vehicle restarts, in an intermediate standstill state (t.sub.1 to t.sub.4), in which an automatic restart is carried out without confirmation by the driver, the following measures that are configured to increase attentiveness and/or starting safety, which differ from measures for an automatic restart before the specified period of time: a) producing at least one starting instruction at a start and/or during a start up, wherein the at least one starting instruction comprises a visual, audible, and/or haptic instruction, and one or more of: b) starting with a lower acceleration of the motor vehicle than a maximum acceleration of the motor vehicle that is provided for a restart from a dynamic standstill state (t.sub.0 to t.sub.1); and c) starting with at least a temporary reduction of a speed relative to the restart from the dynamic standstill state in the form of one or more crawling phases.

13. The method of claim 12, wherein the haptic instruction comprises a starting jolt that is configured to be perceptible by the driver of the motor vehicle.

Description

(1) A description of exemplary embodiments using the drawings follows. In the figures:

(2) FIG. 1 shows a sketch for illustrating different standstill states of an adaptive speed controller for a motor vehicle;

(3) FIG. 2 shows graphs of different starting procedures from the standstill states shown in FIG. 1; and

(4) FIG. 3 shows a sketch of different status displays in the standstill states shown in FIG. 1.

(5) An adaptive motor vehicle speed controller contains a stop-and-go system for an automatic or driver-confirmed restart after a motor vehicle standstill because of a vehicle ahead coming to a standstill and starting again.

(6) If the motor vehicle comes to a standstill in such a way, namely at a point in time to in FIG. 1, the stop-and-go system is in a dynamic standstill state, which is so called in view of the possibility of an automatic dynamic start. An automatic restart is also possible from said state if the vehicle ahead (called the target in FIGS. 2 and 3) starts again.

(7) If the vehicle ahead is still not starting and the motor vehicle is still stationary at a point in time t.sub.1 of for example 3 seconds after to, the stop-and-go system enters a first phase of a so-called intermediate standstill state that is also referred to as a “delayed starting phase 1” If the vehicle ahead starts again in said state, an automatic restart of the motor vehicle is carried out that includes a starting jolt and that otherwise is carried out with a lower acceleration of the motor vehicle than for dynamic starting.

(8) This is illustrated in FIG. 2, which shows the acceleration for an automatic restart from different standstill states as a function of the time elapsed after the point in time to or the time at a standstill t. The starting jolt shows up as a small hump at the start of the acceleration/time curve.

(9) Furthermore, an audible instruction can be given using onboard loudspeakers of the motor vehicle, as illustrated in FIG. 2. If said instruction is given in a temporal relationship to a vehicle jerk, said audible instruction can be a noise that is typical of a vehicle jerk, so that the perceptibility of the vehicle jerk is boosted; however, it can also be a usual instruction tone (for example a “chime” tone signal) or a voice message or similar.

(10) If the vehicle ahead also does not start during phase 1 and the motor vehicle is still stationary at a point in time t.sub.2 of for example 8 seconds after to, the stop-and-go system enters a second phase of the intermediate standstill state, also referred to as the “delayed starting phase 2” If the vehicle ahead starts again in said state, an automatic restart of the motor vehicle is carried out that includes a starting jolt and a still lower acceleration than in phase 1 and moreover a short crawling movement, for example a not accelerated or only slightly accelerated movement with up to 1 or 2 km/h, immediately after the starting jolt.

(11) If the vehicle ahead does not even start during phase 2 and the motor vehicle is still stationary at a point in time t.sub.3 of for example 15 seconds after to, the stop-and-go system enters a third phase of the intermediate standstill state, also referred to as the “delayed starting phase 3”. If the vehicle ahead starts again in said state, an automatic restart of the motor vehicle is carried out that contains a starting jolt, a brief crawling movement and a similarly small acceleration as in phase 2 and moreover at least one further starting jolt immediately after the crawling movement.

(12) If the vehicle ahead does not even start during the phase 3 and the motor vehicle is still stationary at a point in time t.sub.4 of for example 22 seconds after to, the stop-and-go system enters a confirmation standstill state, from which an automatic restart is only still possible if the driver confirms this, for example by tapping the gas pedal or operating a button. Alternatively, further staged phases of the intermediate standstill state can also be provided.

(13) The different standstill states can be displayed to the driver on a visual display on the instrument panel by different symbols that illustrate the corresponding standstill state and also optionally distinguish whether the vehicle ahead is at a standstill or just starting up.

(14) As shown in FIG. 3 to the driver of the motor vehicle (called the host in FIGS. 1 and 3) during the dynamic starting phase for example a symbol without a legend for a vehicle ahead is displayed, and this is regardless of whether the vehicle ahead (the target of the speed control) has just stopped or started.

(15) During phases 1 through 3 of the intermediate standstill state, the driver is shown the same symbol, but with a legend indicating readiness for safe restarting when the target has stopped and which when the target has just started up indicates that safe automatic starting is active and that the driver can end said starting procedure and can proceed with normal dynamic starting by pressing a “RES(ume)” button. This can be desired by the driver if he feels that safe automatic starting is unnecessarily slow.

(16) If the motor vehicle is still stopped after phase 3, the driver is shown the same symbol, but with a legend that indicates the stopped state when the target is stopped and which when the target is starting or no longer present indicates that the driver must press the “RES(ume)” button if he wants to continue his journey.