Method for safe automatic centering of a vehicle in a traffic lane
The method adjusts alert durations and deactivation thresholds based on hand removal frequency and duration to prevent misuse of lane centering systems, enhancing driver vigilance and reducing false positives.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- AMPERE SAS
- Filing Date
- 2025-12-08
- Publication Date
- 2026-06-18
AI Technical Summary
Existing lane centering systems in vehicles face issues with false positive hand detection, leading to frequent deactivation of the function and discouraging driver usage, while allowing skilled drivers to misuse the system by keeping hands off the wheel for extended periods without adequate alerts.
A method that dynamically adjusts alert durations and deactivation thresholds based on the frequency and duration of hand removal from the steering wheel, progressively increasing alert intrusiveness and eventually disabling the lane centering function to ensure driver vigilance.
Effectively prevents misuse of the lane centering function by ensuring the driver remains attentive, reducing false positives, and minimizing unnecessary deactivations through adaptive alert strategies.
Smart Images
Figure EP2025085852_18062026_PF_FP_ABST
Abstract
Description
DESCRIPTION TITLE: Method for the safe automatic centering of a vehicle in a traffic lane TECHNICAL FIELD OF THE INVENTION
[0001] The technical field of the invention is that of safety functions in vehicles, and more particularly that of trajectory control functions in vehicles.
[0002] The present invention relates to a method for centering a vehicle in a traffic lane, and in particular to a safe, automatic method for centering a vehicle in a traffic lane. The invention also relates to a vehicle and a computer program for implementing the method. TECHNOLOGICAL BACKGROUND OF THE INVENTION
[0003] The lane centering function is a feature that centers a vehicle within its lane without the driver having to apply any torque to the steering wheel. However, this does not relieve the driver of the need to remain vigilant and ready to take control of the vehicle. Therefore, the lane centering function is coupled with a driver hand detection system. This system determines when the driver is relying too heavily on the lane centering function and removing their hands from the wheel, triggering a series of alerts, ultimately deactivating the lane centering function, depending on the duration the driver's hands are off the wheel.
[0004] Theoretically, to improve safety, the alert durations should be minimized, reminding the driver to remain fully in control of the vehicle and preventing accidents. However, systems that detect the driver's hands on the steering wheel generate numerous false positives, meaning they detect that the driver's hands are not on the wheel when they actually are. Furthermore, alert durations that are too short would lead to many unwarranted deactivations of the lane centering function, discouraging drivers from using it.
[0005] The duration of alerts is therefore currently the result of a compromise between a level of service quality and security.
[0006] A skilled driver can therefore misuse the function, regularly removing their hands from the steering wheel without intrusive alerts and thus being quite inattentive for long periods.
[0007] Therefore, there is a need to prevent any misuse of the lane centering function without compromising the service provided. SUMMARY OF THE INVENTION
[0008] The invention offers a solution to the problems mentioned above, by ensuring that the driver is in control of his vehicle when the lane centering function is activated, without increasing the number of undue deactivations of the function.
[0009] A first aspect of the invention relates to a method for the safe automatic centering of a vehicle in a traffic lane, comprising the following steps: If the value of a counter is below a deactivation threshold, an automatic vehicle centering function is activated within the traffic lane; If the driver's hands are not detected on the steering wheel for an initial period, the counter is incremented by an initial value; If the driver's hands are not detected on the steering wheel for a second period longer than the first period, at least one alert will be issued to the driver; During the emission stage: If the driver's hands are not detected on the steering wheel for a third duration, the counter is incremented by a second value; If the driver's hands are not detected on the steering wheel for a fourth duration greater than the third duration, the centering function is automatically deactivated; the value of the second duration and the value of the fourth duration depend on the value of the counter at the time of the activation step.
[0010] Thanks to the invention, the duration for which the driver's hands are not detected before an alert is issued and the duration for which the hands Driver behaviors that go undetected before lane centering are deactivated vary depending on the number of times the driver removes their hands from the steering wheel during a trip and for how long. Thus, the durations decrease and the alerts become increasingly intrusive as the frequency and / or duration of hand removal increases, ultimately leading to the lane centering function being disabled to make the driver aware of the danger of their behavior.
[0011] In addition to the characteristics mentioned in the preceding paragraph, the process according to the invention may have one or more additional characteristics from among the following, considered individually or according to all technically possible combinations.
[0012] According to one embodiment, the process according to the invention comprises the following steps: If the driver's hands are not detected on the steering wheel during the second period, a first alert is issued; During the first alert issuance stage, if the driver's hands are not detected on the steering wheel for a sixth duration, a second alert is issued; During the second alert issuance stage, if the driver's hands are not detected on the steering wheel for a fifth duration, the counter is incremented by a third value; the value of the sixth duration depends on the value of the counter at the time of the activation stage.
[0013] According to a sub-embodiment of the previous embodiment, the first alert is a visual alert and the second alert is an audible and visual alert.
[0014] Thus, the intrusive nature of the alerts increases as the time since the last detection of the driver's hands on the steering wheel increases.
[0015] According to an embodiment compatible with the previous embodiment, the deactivation step of the centering function includes a substep of issuing a third alert.
[0016] Thus, the driver is warned of the deactivation of the centering function.
[0017] According to an embodiment compatible with previous embodiments, the counter is reset to zero each time the vehicle is restarted.
[0018] According to an embodiment compatible with the previous embodiments, the value of the second duration and / or the fourth duration and / or the sixth duration is decreased as soon as the value of the counter exceeds a penalty threshold among a set of penalty thresholds including the deactivation threshold.
[0019] Thus, the time before alert and the durations of the alerts are gradually reduced, each time a penalty threshold is crossed by the counter, until the centering function is blocked.
[0020] According to an embodiment compatible with the previous embodiments, the method according to the invention includes a step of displaying an indicator of the last sanction threshold exceeded by the value of the counter.
[0021] Thus, the driver is informed of the reduction in the time before alert and the alert durations related to the centering function.
[0022] According to an embodiment compatible with previous embodiments, the centering function can no longer be activated if the counter value is strictly greater than the deactivation threshold.
[0023] Thus, a driver who has engaged in abusive behavior will temporarily no longer be able to use the centering function, for example until the next time the vehicle is restarted.
[0024] A second aspect of the invention relates to a vehicle comprising means for implementing the process according to the invention.
[0025] A third aspect of the invention relates to a computer program product comprising instructions which, when the program is executed by a computer, lead the computer to implement the steps of the process according to the invention.
[0026] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES
[0027] The figures are presented for illustrative purposes only and are in no way limiting to the invention. Figure 1 is a synoptic diagram illustrating the sequence of steps of a process according to the invention. Figure 2 shows a schematic representation of a vehicle on which the process according to the invention is applied, as a function of time. DETAILED DESCRIPTION
[0028] Unless otherwise specified, the same element appearing on different figures has a unique reference.
[0029] The invention relates to a method for centering a vehicle in a traffic lane on which the vehicle is traveling, and this in an automatic, i.e. without intervention from a driver of the vehicle, and in a safe manner.
[0030] The sequence of steps in process 100 is illustrated in Figure 1 and their effects on vehicle 200 as a function of time are illustrated in Figure 2.
[0031] A first step 101 of process 100 consists of activating a function implemented on vehicle 200, allowing automatic centering of vehicle 200 in the traffic lane.
[0032] Such an activation can be carried out automatically or by the driver of vehicle 200.
[0033] In figure 2, the first step 101 is carried out at time t0.
[0034] The first step 101 is only performed if the value of a counter is less than a deactivation threshold.
[0035] For example, the counter is reset to zero each time the vehicle is restarted.
[0036] Thus, the centering function can no longer be activated if the counter value is strictly greater than the deactivation threshold.
[0037] A second step 102 of process 100 is implemented if the driver's hands are not detected on the steering wheel for a duration, referred to as the first duration D1, following the activation of the lane centering function during the first step 101.
[0038] Detection is carried out, for example, via one or more capacitive sensors integrated into the steering wheel of vehicle 200.
[0039] In figure 2, the first duration D1 extends between the instants t0 and t1.
[0040] The second step 102 consists of incrementing the counter by a first value.
[0041] A third step 103 of process 100 is implemented if the driver's hands are not detected on the steering wheel for a duration, called second duration D2, following the activation of the lane centering function during the first step 101.
[0042] The second duration D2 is greater than the first duration D1.
[0043] In figure 2, the second duration D2 extends between the times t0 and t2.
[0044] The value of the second duration D2 depends on the value of the counter at the time of the first step 101.
[0045] The third step 103 consists of issuing an alert, called the first alert, to the driver of vehicle 200.
[0046] The first alert is, for example, a visual alert, the visual alert consisting, for example, of the display of a message on a screen of the vehicle 200, the message being, for example, "Keep your hands on the steering wheel".
[0047] The third step 103 may include a sub-step 1031 implemented if the driver's hands are not detected on the steering wheel for a duration called the third duration D3, following the second duration D2, i.e. during the third step 103.
[0048] In figure 2, the third duration D3 extends between times t2 and t3.
[0049] Substep 1031 of third step 103 consists of incrementing the counter by a second value.
[0050] A fourth step 104 of the process 100 is implemented if the driver's hands are not detected on the steering wheel for a period called the sixth duration D6, following the second duration D2, i.e. during the third step 103.
[0051] The sixth duration D6 is greater than the third duration D3.
[0052] In figure 2, the sixth duration D6 extends between times t2 and t4.
[0053] The value of the sixth duration D6 depends on the value of the counter at the time of the first step 101.
[0054] The fourth step 104 consists of issuing an alert, called the second alert, to the driver of vehicle 200.
[0055] The second alert is, for example, a visual and audible alert, the alert consisting, for example, of the display of a message on a screen of the vehicle 200, the message being, for example, "Keep your hands on the steering wheel" and the emission of an audible signal.
[0056] The fourth step 104 may include a substep 1041 implemented if the driver's hands are not detected on the steering wheel for a period called the fifth duration D5, following the sixth duration D6, i.e. during the fourth step 104.
[0057] In figure 2, the fifth duration D5 extends between times t4 and t5.
[0058] Substep 1041 consists of incrementing the counter by a third value.
[0059] A fifth step 105 of process 100 is implemented if the driver's hands are not detected on the steering wheel for a period, called the fourth period D4, following the second period D2, which extends during the alert step(s) 103, 104.
[0060] The fourth duration D4 is greater than the fifth duration D5 and the sixth duration D6.
[0061] In figure 2, the fourth duration D4 extends between times t2 and t6.
[0062] The value of the fourth duration D4 depends on the value of the counter at the time of the first step 101.
[0063] The fifth step 105 consists of disabling the centering function, and thus giving control back to the driver of vehicle 200.
[0064] Deactivation is performed automatically.
[0065] In figure 2, the deactivation is carried out at time t6.
[0066] The fifth step 105 may include a sub-step 1051 of issuing an alert, known as the third alert.
[0067] The third alert, for example, is an audible alert and consists of the emission of a sound signal.
[0068] The value of the second duration D2, the fourth duration D4 and the sixth duration D6 are, for example, reduced as soon as the value of the counter exceeds a penalty threshold among a set of penalty thresholds.
[0069] The set of sanction thresholds includes a plurality of sanction thresholds, among which is the deactivation threshold.
[0070] The deactivation threshold is higher than all other sanction thresholds in the set of sanction thresholds.
[0071] The set of sanction thresholds includes, for example, two sanction thresholds and the deactivation threshold.
[0072] In a purely illustrative example, the set of sanction thresholds includes a first sanction threshold with a value of 4, a second sanction threshold with a value of 6, and a deactivation threshold with a value of 8; the first value is 1, the second value the value is 2, the third value is 3, the first duration D1 is 5 seconds, the third duration D3 is 5 seconds and the fifth duration D5 is 10 seconds.
[0073] The second duration D2 is initialized to 15 seconds, the sixth duration D6 to 15 seconds and the fourth duration D4 to 45 seconds.
[0074] As soon as the counter exceeds the first penalty threshold, the second duration D2 is reduced to 6 seconds, the sixth duration D6 to 6 seconds and the fourth duration D4 to 36 seconds.
[0075] As soon as the counter exceeds the second penalty threshold, the second duration D2 is reduced to 6 seconds, the sixth duration D6 to 6 seconds and the fourth duration D4 to 16 seconds.
[0076] As soon as the counter exceeds the deactivation threshold, the centering function can no longer be activated temporarily, for example until the next vehicle restart 200.
[0077] The method 100 according to the invention may include a step 1011 consisting of displaying an indicator of the last sanction threshold exceeded by the value of the counter.
[0078] For example, a yellow indicator is displayed when the counter has exceeded the first penalty threshold, an orange indicator when the counter has exceeded the second penalty threshold, and a red indicator when the counter has exceeded the deactivation threshold.
Claims
DEMANDS 1. A method (100) for the safe automatic centering of a vehicle (200) in a traffic lane, comprising the following steps: If the value of a counter is below a deactivation threshold, activation (101) of an automatic vehicle centering function (200) in the traffic lane; If the driver's hands are not detected on the steering wheel for a first duration (D1), the counter is incremented (102) by a first value; If the driver's hands are not detected on the steering wheel for a second duration (D2) greater than the first duration (D1), emission (103, 104) of at least one alert to the driver; During the emission stage (103, 104): If the driver's hands are not detected on the steering wheel for a third duration (D3), increment (1031) the counter by a second value; If the driver's hands are not detected on the steering wheel for a fourth duration (D4) greater than the third duration (D3), automatic deactivation (105) of the centering function; the method (100) being characterized in that the value of the second duration (D2) and the value of the fourth duration (D4) depend on the value of the counter at the time of the activation step (101).
2. A method (100) according to any one of the preceding claims, comprising the following steps: If the driver's hands are not detected on the steering wheel during the second duration (D2), a first alert (103) is issued; During the first alert issuance step (103), if the driver's hands are not detected on the steering wheel for a sixth duration (D6), a second alert is issued (104); During the second alert issuance step (104), if the driver's hands are not detected on the steering wheel for a fifth duration (D5), the counter is incremented (1041) by a third value; the value of the sixth duration (D6) depends on the value of the counter at the time of the activation step (101).
3. Method (100) according to the preceding claim, wherein the first alert is a visual alert and the second alert is an audible and visual alert.
4. Method (100) according to any one of the preceding claims, wherein the step (105) of deactivating the centering function includes a substep (1051) of issuing a third alert.
5. Method (100) according to any one of the preceding claims, wherein the counter is reset to zero at each restart of the vehicle (200).
6. Method (100) according to any one of the preceding claims, wherein the value of the second duration (D2) and / or the fourth duration (D4) and / or the sixth duration (D6) is decreased as soon as the value of the counter exceeds a penalty threshold among a set of penalty thresholds including the deactivation threshold.
7. Method (100) according to any one of the preceding claims, comprising a step (1011) of displaying an indicator of the last penalty threshold exceeded by the value of the counter.
8. Method (100) according to any one of the preceding claims, wherein the centering function can no longer be activated if the value of the counter is strictly greater than the deactivation threshold.
9. Vehicle (200) comprising means for implementing the method (100) according to any one of the preceding claims.
10. Product computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the steps of the process (100) according to any one of claims 1 to 8.