Automatic vehicle brake control system

Abstract

Provided is an automatic vehicle brake control system. A method of automated vehicle braking control includes detecting a first object threat in a reverse travel path of a vehicle, monitoring a distance of the vehicle from the first object threat relative to a time threshold to a collision, and responsive to a determination that the vehicle is crossing the time threshold to the collision, determining that the vehicle is crossing the time threshold to the collision. A first rear virtual bumper event is initiated by automatically applying braking of the vehicle. The method includes storing a location of a first object threat, defining a boundary region surrounding the location of the first object threat, detecting a second object threat in the reverse travel path, comparing the location of the second object threat to the boundary region, and in response to a determination that the location of the second object threat is within the boundary region, determining that the second object threat is within the boundary region. Automatic application of braking is prohibited to avoid a second rear virtual bumper event.

Description

[0001] introduce

[0002] The information provided in this section is for the purpose of generally presenting the context of the present disclosure. The work of the presently named inventors is neither explicitly nor implicitly admitted to be prior art against the present disclosure to the extent it is described in this section and in aspects of the description that might not otherwise be prior art at the time of filing.

[0003] The present disclosure generally relates to an automatic vehicle braking control system including a sensor for initiating a rear virtual bumper event in response to a detected object threat.

[0004] Some vehicles include object detection sensors that determine whether an object is in the reverse travel path of the vehicle in order to avoid collisions with other objects when the vehicle is backing up. When the vehicle approaches an object, the vehicle can alert the driver through automatic application of vehicle brakes and an audible alarm. Summary of the invention

[0005] A method of automated vehicle brake control includes detecting a first object threat in a reverse travel path of the vehicle via at least one vehicle sensor, monitoring a distance of the vehicle from the first object threat relative to a time to collision threshold, and in response to a determination that the vehicle is crossing the time to collision threshold, initiating a first rear virtual bumper event by automatically applying brakes of the vehicle. The method includes storing a location of the first object threat, defining a boundary area around the location of the first object threat, after the first rear brake event, detecting a second object threat in the reverse travel path via at least one vehicle sensor, comparing the location of the second object threat to the boundary area, and in response to a determination that the location of the second object threat is within the boundary area, inhibiting automatic application of brakes to avoid a second rear virtual bumper event.

[0006] In other features, the method includes generating an audible alert during the first rear virtual bumper event, and in response to determining that the location of the second object threat is within the boundary region, inhibiting generation of the audible alert.

[0007] In other features, detecting the first object threat occurs during a first reverse vehicle movement trajectory of the vehicle, detecting the second object threat occurs during a second reverse vehicle movement trajectory of the vehicle, and detecting a forward movement trajectory of the vehicle precedes detecting the second object threat.

[0008] In other features, the method includes using dead reckoning to update the position of the boundary region relative to the position of the vehicle at an end of the vehicle's forward movement trajectory.

[0009] In other features, the boundary region is defined to have a first radius at a first point in time, the method includes increasing the size of the boundary region to a second radius at a second point in time, and the second point in time is a fixed period after the first point in time.

[0010] In other features, the method includes increasing the size of the boundary region to a third radius at a third point in time, where the third point in time is a fixed period after the second point in time.

[0011] In other features, the fixed period is less than or equal to ten seconds, the first radius is less than or equal to twenty centimeters, the second radius is less than or equal to fifty centimeters, and the third radius is less than or equal to one meter.

[0012] In other features, the method includes eliminating the boundary area after a specified period of time to allow automatic application of braking in response to detecting a third object threat at a location previously covered by the boundary area.

[0013] In other features, the designated time period is less than or equal to thirty seconds. In other features, the method includes restarting the designated time period in response to subsequent detection of another object threat within the boundary area before expiration of the designated time period.

[0014] In other features, the boundary area is a first boundary area, and the method further includes detecting, via at least one vehicle sensor, a third object threat in a reverse travel path of the vehicle, storing a location of the third object threat, and defining a second boundary area around the location of the third object threat.

[0015] In other features, at least one vehicle sensor includes at least one of a camera, a laser detector, and a lidar detector.

[0016] An automated vehicle brake control system includes a brake control module configured to automatically apply brakes of a vehicle in response to a rear virtual bumper event signal, at least one vehicle sensor configured to detect an object threat in a reverse travel path of the vehicle, and a vehicle control module in communication with the brake control module and the at least one vehicle sensor. The vehicle control module is configured to detect a first object threat in the reverse travel path of the vehicle via the at least one vehicle sensor, monitor a distance of the vehicle from the first object threat relative to a time to collision threshold, transmit a signal indicating a first rear virtual bumper event to the brake control module to automatically apply brakes of the vehicle in response to a determination that the vehicle is crossing the time to collision threshold, store a location of the first object threat, define a boundary area around the location of the first object threat, detect a second object threat in the reverse travel path via the at least one vehicle sensor after the first rear virtual bumper event, compare the location of the second object threat to the boundary area, and in response to a determination that the location of the second object threat is within the boundary area, inhibit automatic application of brakes to avoid a second rear virtual bumper event.

[0017] In other features, the vehicle control module is configured to generate an audible alert during the first rear virtual bumper event, and in response to a determination that the location of the second object threat is within the boundary region, inhibit generation of the audible alert.

[0018] In other features, the vehicle control module is configured to detect a first object threat during a first reverse vehicle movement trajectory of the vehicle, detect a second object threat during a second reverse vehicle movement trajectory of the vehicle, and detect a forward movement trajectory of the vehicle before detecting the second object threat.

[0019] In other features, the vehicle control module is configured to use dead reckoning to update the position of the boundary region relative to the position of the vehicle at an end of the forward movement trajectory of the vehicle.

[0020] In other features, the boundary area is defined to have a first radius at a first point in time, the vehicle control module is configured to increase the size of the boundary area to a second radius at a second point in time, and the second point in time is a fixed period after the first point in time.

[0021] In other features, the vehicle control module is configured to increase the size of the bounding area to a third radius at a third point in time, and the third point in time is a fixed period after the second point in time.

[0022] In other features, the fixed period is less than or equal to ten seconds, the first radius is less than or equal to twenty centimeters, the second radius is less than or equal to fifty centimeters, and the third radius is less than or equal to one meter.

[0023] In other features, the vehicle control module is configured to eliminate the boundary area after a specified period of time to allow automatic application of braking in response to detecting a third object threat at a location previously covered by the boundary area.

[0024] A method for automated vehicle brake control is disclosed, the method comprising: detecting a first object threat in a reverse travel path of the vehicle via at least one vehicle sensor; monitoring a distance of the vehicle from the first object threat relative to a time-to-collision threshold; in response to a determination that the vehicle is crossing the time-to-collision threshold, initiating a first rear virtual bumper event by automatically applying brakes of the vehicle; storing a location of the first object threat; defining a boundary area around the location of the first object threat; after the first rear braking event, detecting a second object threat in the reverse travel path via at least one vehicle sensor; comparing the location of the second object threat to the boundary area; and in response to a determination that the location of the second object threat is within the boundary area, prohibiting automatic application of brakes to avoid a second rear virtual bumper event.

[0025] In other features, the method further comprises: generating an audible alert during the first rear virtual bumper event; and in response to determining that the location of the second object threat is within the boundary area, inhibiting generation of the audible alert.

[0026] In other features, detecting the first object threat occurs during a first reverse vehicle movement trajectory of the vehicle; detecting the second object threat occurs during a second reverse vehicle movement trajectory of the vehicle; and detecting the forward movement trajectory of the vehicle precedes detecting the second object threat.

[0027] In other features, the method further includes updating the position of the boundary region relative to the position of the vehicle at an end of the forward movement trajectory of the vehicle using dead reckoning.

[0028] In other features, the boundary region is defined as having a first radius at a first point in time; the method includes increasing the size of the boundary region to a second radius at a second point in time; and the second point in time is a fixed period after the first point in time.

[0029] In other features, the method further includes increasing the size of the boundary region to a third radius at a third point in time, wherein the third point in time is a fixed period after the second point in time.

[0030] In other features, the fixed period is less than or equal to ten seconds; the first radius is less than or equal to twenty centimeters; the second radius is less than or equal to fifty centimeters; and the third radius is less than or equal to one meter.

[0031] In other features, the method further includes eliminating the boundary area after a specified period of time to allow automatic application of braking in response to detecting a third object threat at a location previously covered by the boundary area.

[0032] In other features, the specified time period is less than or equal to thirty seconds.

[0033] In other features, the method further comprises restarting the designated time period in response to subsequent detection of another object threat within the boundary area before expiration of the designated time period.

[0034] In other features, the boundary area is a first boundary area, and the method further includes: detecting a third object threat in a reverse travel path of the vehicle via at least one vehicle sensor; storing a location of the third object threat; and defining a second boundary area around the location of the third object threat.

[0035] In other features, at least one vehicle sensor includes at least one of a camera, a laser detector, and a lidar detector.

[0036] An automated vehicle brake control system is disclosed, comprising: a brake control module configured to automatically apply brakes of a vehicle in response to a rear virtual bumper event signal; at least one vehicle sensor configured to detect an object threat in a reverse travel path of the vehicle; and a vehicle control module in communication with the brake control module and the at least one vehicle sensor, the vehicle control module configured to: detect a first object threat in the reverse travel path of the vehicle via the at least one vehicle sensor; monitor a distance of the vehicle from the first object threat relative to a time to collision threshold; in response to a determination that the vehicle is crossing the time to collision threshold, transmit a signal indicating a first rear virtual bumper event to the brake control module to automatically apply brakes of the vehicle; store a location of the first object threat; a boundary area defined around the location of the first object threat; after the first rear virtual bumper event, detect a second object threat in the reverse travel path via the at least one vehicle sensor; compare the location of the second object threat to the boundary area; and in response to a determination that the location of the second object threat is within the boundary area, inhibit automatic application of brakes to avoid a second rear virtual bumper event.

[0037] In other features, the vehicle control module is configured to: generate an audible alert during the first rear virtual bumper event; and in response to a determination that the location of the second object threat is within the boundary region, inhibit generation of the audible alert.

[0038] In other features, the vehicle control module is configured to: detect a first object threat during a first reverse vehicle movement trajectory of the vehicle; detect a second object threat during a second reverse vehicle movement trajectory of the vehicle; and detect a forward movement trajectory of the vehicle before detecting the second object threat.

[0039] In other features, the vehicle control module is configured to use dead reckoning to update the position of the boundary region relative to the position of the vehicle at an end of the forward movement trajectory of the vehicle.

[0040] In other features, the boundary area is defined to have a first radius at a first point in time; the vehicle control module is configured to increase the size of the boundary area to a second radius at a second point in time; and the second point in time is a fixed period after the first point in time.

[0041] In other features, the vehicle control module is configured to increase the size of the bounding area to a third radius at a third point in time; and the third point in time is a fixed period after the second point in time.

[0042] In other features, the fixed period is less than or equal to ten seconds; the first radius is less than or equal to twenty centimeters; the second radius is less than or equal to fifty centimeters; and the third radius is less than or equal to one meter.

[0043] In other features, the vehicle control module is configured to eliminate the boundary area after a specified period of time to allow automatic application of braking in response to detecting a third object threat at a location within a location previously covered by the boundary area.

[0044] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present disclosure will be more fully understood based on the detailed description and accompanying drawings, in which:

[0046] Figure 1 is a diagram of an example vehicle including an automatic braking control system.

[0047] Figure 2A is a graph of vehicles approaching a time-to-collision (TTC) threshold during a reverse travel path trajectory.

[0048] Figure 2B is a diagram showing the crossing of the TTC threshold Figure 2A of the vehicle.

[0049] Figure 3 It is a diagram about Figure 2AA plot of the growth of the object boundary area of ​​a vehicle over time.

[0050] Figure 4 It's a picture. Figure 2A FIG. 1 is a diagram of a second reverse driving path trajectory of a vehicle.

[0051] Figure 5 is a flow chart depicting an example process for controlling automatic vehicle braking in response to a rear virtual bumper event.

[0052] Figure 6 is a flow chart depicting an example process for dead reckoning the position of an object threat relative to the motion of a vehicle.

[0053] Figure 7 is a flow chart depicting an example process for adjusting and decaying a boundary area of ​​a detected object threat over time.

[0054] In the drawings, reference numbers may be reused to identify similar and / or identical elements. DETAILED DESCRIPTION

[0055] Some vehicles include sensors to provide automatic braking when approaching a detected object threat while the vehicle is traveling in reverse. In some example embodiments, the vehicle control module is configured to inhibit or prevent multiple alarm and braking events for the same object target in a noisy sensor environment in order to reduce false activation complaints.

[0056] For example, a vehicle control module may use dead reckoning logic to monitor the movement of the vehicle while using existing vehicle sensors to estimate the location or area of ​​the most recently identified object threat. An example algorithm tracks a dynamic boundary region about a high threat target object, and if a subsequent high threat target object is identified in the boundary region, any further alarm and braking actions may be suppressed. The boundary region decays slowly as a function of time to allow for future alarm and braking events after a specified period(s).

[0057] Reference now Figure 1 , the vehicle 10 includes front wheels 12 and rear wheels 13. Figure 1 , the drive unit 14 selectively outputs torque to the front wheels 12 and / or the rear wheels 13 via drive lines 16, 18, respectively. The vehicle 10 may include different types of drive units. For example, the vehicle may be an electric vehicle, such as a battery electric vehicle (BEV), a hybrid vehicle or a fuel cell vehicle, a vehicle including an internal combustion engine (ICE), or other types of vehicles.

[0058] Some examples of drive unit 14 may include any suitable electric motor, a power inverter, and a motor controller configured to control a power switch within the power inverter to adjust motor speed and torque during propulsion and / or regeneration. During propulsion or regeneration, the battery system provides power to or receives power from the electric motor of drive unit 14 via the power inverter.

[0059] Although in Figure 1 The vehicle 10 includes one drive unit 14, but the vehicle 10 may have other configurations. For example, two separate drive units may drive the front wheels 12 and the rear wheels 13, one or more individual drive units may drive individual wheels, etc. As can be appreciated, other vehicle configurations and / or drive units may be used.

[0060] The vehicle control module 20 may be configured to control the operation of one or more vehicle components, such as the drive unit 14 (e.g., by commanding a torque setting of an electric motor of the drive unit 14). The vehicle control module 20 may receive inputs for controlling components of the vehicle, such as signals received from a steering wheel, an accelerator pedal, etc. The vehicle control module 20 may monitor vehicle telematics for safety purposes, such as vehicle speed, vehicle position, vehicle braking and acceleration, etc.

[0061] The vehicle control module 20 may receive signals from any suitable component for monitoring one or more aspects of the vehicle or surrounding environment, including one or more vehicle sensors (such as cameras, lasers, lidar sensors, microphones, pressure sensors, wheel position sensors, position sensors such as global positioning system (GPS) antennas, etc.) Some sensors may be configured to monitor the current motion of the vehicle, the acceleration of the vehicle, steering torque, etc.

[0062] like Figure 1 As shown in FIG. 1 , the vehicle 10 includes a rear object detector 24 and an optional side object detector 28. In various implementations, the vehicle 10 may include more or less (or none) of any of these optional sensors (including a front object detector, etc.). Each object sensor may include any suitable camera, laser, lidar sensor, etc. for detecting objects around the vehicle 10. In some example embodiments, the vehicle object detector may be configured to detect one or more object threats in the reverse travel path trajectory of the vehicle 10, a closest in-path vehicle (CIPV) (e.g., another vehicle ahead of the current travel path of the vehicle 10), a vulnerable road user (VRU) (e.g., a pedestrian or cyclist), etc.

[0063] The vehicle control module 20 can communicate with another device via a wireless communication interface, which may include one or more wireless antennas for transmitting and / or receiving wireless communication signals. For example, the wireless communication interface can communicate via any suitable wireless communication protocol, including but not limited to vehicle-to-everything (V2X) communication, Wi-Fi communication, wireless area network (WAN) communication, cellular communication, personal area network (PAN) communication, short-range wireless communication (e.g., Bluetooth), etc. The wireless communication interface can communicate with a remote computing device via one or more wireless and / or wired networks. With respect to vehicle-to-vehicle (V2X) communication, the vehicle 10 may include one or more V2X transceivers (e.g., V2X signal transmission and / or reception antennas).

[0064] like Figure 1 As shown in FIG. 1 , the vehicle 10 includes a vehicle brake 26. Although for ease of illustration, Figure 1 The vehicle brake is shown at only one of the wheels 12, but the vehicle brake may be located at each wheel, at each axle, etc., and may be configured to be selectively applied at each wheel independently of the other wheels, at each axle independently of the other axle(s), etc.

[0065] Each vehicle brake 26 may be controlled by a vehicle control module 20, which may include one or more electronic brake control systems (which may be located in a control center of the vehicle, distributed adjacent to the brakes at each wheel, etc.) For example, the vehicle control module 20 may send an electronic signal to activate the vehicle brake 26, such as via an electronically controlled actuator.

[0066] In some example embodiments, the vehicle control module 20 may be configured to automatically apply the vehicle brakes 26 in response to detecting an object threat, such as an object detected by the rear object detector 24, in the reverse travel path of the vehicle 10. The vehicle control module 20 may automatically apply the vehicle brakes 26 (and / or generate an audible alarm) to prevent the vehicle from striking the detected object while in reverse. This may be considered a rear virtual bumper (RVB) event.

[0067] As further described herein, in some example embodiments, the vehicle control module 20 may be configured to track the position of a detected object threat relative to the vehicle 10 (which may be updated based on the movement of the vehicle using dead reckoning), and inhibit subsequent RVB events. For example, once an RVB event has occurred for a detected object, the vehicle control module 20 may assume that the driver is now aware of the object, such that if the driver decides to continue backing up, etc., the automatic application of brakes for the same object threat location may be inhibited (thus, after the driver has become aware of the detected object threat, they will not receive subsequent alerts and / or automatic braking events).

[0068] Figure 2A 1 is a diagram illustrating vehicle 110 traveling along reverse travel path 102 (eg, reversing the vehicle in the direction of the arrow). Object sensors of the vehicle detect first object 106 and second object 108 along reverse travel path 102.

[0069] like Figure 2A As shown in , a time-to-collision (TTC) threshold 104 is determined by a vehicle control module. For example, the TTC threshold 104 can be specified as a distance from a first object 106 or a second object 108 at which a driver of the vehicle 110 should be warned to slow down or change the reverse travel path 102 in order to avoid a rear collision with the first object 106 or the second object 108.

[0070] The TTC threshold 104 may be determined based on the speed of the vehicle 110 , the distance to the first object 106 or the second object 108 , the average reaction time of the vehicle's driver, etc. The TTC threshold 104 may be determined based on whichever of the first object 106 and the second object 108 is closest to the vehicle 110 along the reverse travel path 102 (e.g., the object that the vehicle 110 will most likely strike first if it continues to reverse along the reverse travel path 102 ).

[0071] Figure 2B An example scenario is shown where vehicle 110 has reached or crossed TTC threshold 104. For example, Figure 2A The position of the vehicle at time t0 can be illustrated, where Figure 2B The position of the vehicle at a subsequent time t1 is illustrated.

[0072] When vehicle 110 crosses TTC threshold 104, Figure 2B As shown in , the vehicle control module can determine that a rear virtual bumper (RVB) event has occurred. For example, before the vehicle 110 collides with the first object 106 or the second object 108, the vehicle control module can automatically apply the brakes to stop the reverse movement of the vehicle 110 and alert the driver.

[0073] The vehicle control module may apply the brakes only briefly, temporarily, etc. for a short period of time, which alerts the driver of the vehicle 110. The brakes may be released after a period of time (e.g., 500 milliseconds, one second, three seconds, etc.), or the brakes may be applied until the driver provides another vehicle control input, such as depressing an accelerator pedal, depressing a brake pedal, or turning a steering wheel.

[0074] In some example embodiments, when a rear virtual bumper event occurs, the vehicle control module may sound an alert. For example, the vehicle control may sound an auditory warning alert, generate a tactile feedback alert through the steering wheel or the driver's seat, etc.

[0075] Figure 3 It is a diagram about Figure 2A The growth of the object boundary area of ​​the vehicle over time. Figure 3 As shown in 2.0 At , the vehicle has moved from vehicle position 110A to vehicle position 110B. The vehicle is moving along forward travel path 103. For example, Figure 2B compared to, Figure 3 The diagram in FIG. 1 may illustrate that the vehicle moves forward and away from the first object 106 and the second object 108 after the driver previously generated an alert and an RVB event while backing up.

[0076] Boundary regions may be generated for each object in order to track the expected location of the object for use in determining whether future RVB events and automatic braking events should be inhibited. Figure 3 As shown in FIG. 1 , a first boundary region 116A is defined around the first object 106 , and a second boundary region 118A is defined around the second object 108 .

[0077] The size of the bounding region may grow over time to account for the estimated position of the objects corresponding to the bounding region over time. For example, as the vehicle moves along forward travel path 103, dead reckoning may be used to update the coordinates of the estimated position of first object 106 and second object 108 relative to the new position of the vehicle. The bounding region may account for changes in the estimated position of the objects as the vehicle moves.

[0078] like Figure 3 As shown in FIG. , the first boundary region 116A at time t 2.1 increases to a larger first boundary region 116B at time t 2.2 Similarly, the second boundary region 118A increases to an even larger first boundary region 116C at time t 2.1 increases to a larger second boundary region 118B at time t 2.2 The boundary region 118C increases to an even larger second boundary region 118C.

[0079] The size of the border region may increase continuously over time, or may increase at periodic intervals, such as every second, every five seconds, every ten seconds, etc. The border region may have any suitable size at each time period, such as a circular border region with a radius of ten centimeters, twenty centimeters, one-fifth of a centimeter, one meter, two meters, etc.

[0080] If a subsequent object threat is detected at a location within the boundary zone, the vehicle control module can inhibit automatic braking and avoid subsequent RVB event alerts. For example, the system can prevent repeated automatic braking and RVB event alerts for object threats detected at the same location (or location within the same boundary zone) where a previous automatic braking and RVB event alert was issued. This can prevent multiple automatic braking events for the same object that the driver is already aware of.

[0081] For example, Figure 3 As shown in 2.2 At 116C, third object threat 120 is detected. Third object threat 120 is located within boundary region 116C corresponding to first object 106. Because the vehicle control module has already issued an RVB event alert for first object 106 at a previous time, the vehicle control module may avoid issuing another RVB event for newly detected third object threat 120 (e.g., because newly detected third object threat 120 may be the same as first object 106 that the driver was already aware of from the previous RVB event alert).

[0082] At time t 2.2 At 100°, the vehicle control module may also detect fourth object threat 122 and fifth object threat 124 outside of the boundary area. If the vehicle crosses the TTC threshold for fourth object threat 122 or fifth object threat 124, the vehicle control module may automatically apply the brakes and generate another RVB event alert (e.g., because fourth object threat 122 and fifth object threat 124 are at locations where the threatening objects were not previously alerted to the driver).

[0083] The boundary region may decay over time so that new object threats detected within a previous boundary region may be allowed to initiate automatic vehicle braking and RVB event alerts again. 2.3 At , the boundary region 118C corresponding to the second object 108 may be discarded due to a specified period of time having passed after an initial detection of the second object 108 or an initial RVB event based on the second object 108 .

[0084] For example, if a first object detection or RVB event based on the second object 108 occurs at time t0, the location may only be tracked for a specified period of time before a new alert may be generated at the same location. If the driver is alerted to the RVB event based on the location of the second object 108, subsequent object threat detections at the same location may be inhibited for five seconds, ten seconds, thirty seconds, etc. (e.g., because the vehicle control module assumes that the driver is aware of the detected and alerted object threat for the period of time). After the period of time has expired, a new object threat detected at the location may initiate automatic braking and an RVB event alert (in case the driver has forgotten about the object, if a new object may appear at a similar location, etc.).

[0085] In some example embodiments, subsequent detection of an object threat within a boundary region may pause or reset the decay of the boundary region. For example, if another object threat is detected within the boundary region at some time after the initial RVB event, the amount of time before the boundary region is discarded may be extended.

[0086] exist Figure 3 In the example of FIG. 1 , at time t2.3, after a specified time period (e.g., five seconds, ten seconds, thirty seconds, etc.) has expired and no additional object threats have been detected within the boundary region 118C, the boundary region 118C corresponding to the second object 108 is discarded. 2.2 A third object threat 120 is detected within the boundary region 116C (which extends the duration of the boundary region 116C), and the boundary region 116 corresponding to the first object 106 is detected at time t 2.3 The place still exists.

[0087] Figure 4 It's a picture. Figure 2A The second reverse driving path trajectory of the vehicle is shown in FIG. Figure 4 , the vehicle is at a third vehicle position 110C, moving along the second reverse travel path 105. For example, after backing up to generate an initial RVB event, and then pulling forward along the forward travel path 103, the vehicle may back up again toward the location of the first object 106 along the second reverse travel path 105 at time t3.

[0088] like Figure 4As shown in , the boundary area 116C corresponding to the first object 106 still exists, while the boundary area corresponding to the position of the second object 108 has decayed. Therefore, if the vehicle control module detects another object threat within the boundary area 116C, subsequent RVB events and automatic braking can be prohibited. However, if the vehicle control module detects a fourth object threat 122 or a fifth object threat 124 adjacent to the old position of the second object 108, another RVB event alarm or automatic braking can occur for the fourth object threat 122 or the fifth object threat 124. In some example embodiments, the detection of the object can be any combination of implementations of vehicle movement, such as 1. backward movement->braking->backward movement; 2. backward movement->forward movement->backward movement; 3. forward movement->braking->forward movement, etc.

[0089] Figure 5 is a flow chart depicting an example process for controlling automatic vehicle braking in response to a rear virtual bumper event. The process may be performed by, for example, Figure 1 The vehicle control module 20 is executed. At 504, a rear virtual bumper (RVB) event occurs (eg, due to an object threat detected in the rear travel path of the vehicle).

[0090] At 508 , the vehicle control module is configured to determine the location of the object threat for which the RVB event occurred. For example, the vehicle control module may use signals received from one or more vehicle object detectors to determine the location of the detected object threat.

[0091] At 512, control is configured to define a bounding area around the location of the object threat. The bounding area may have any suitable size, such as a circle having a diameter of approximately ten centimeters, approximately twenty centimeters, approximately fifty centimeters, approximately one meter, etc.

[0092] At 516, the vehicle control module is configured to track the position of the target relative to the movement of the vehicle using dead reckoning. Figure 6 Additional details of an example dead reckoning algorithm for tracking a moving target position relative to a vehicle are further described.

[0093] At 520 , control receives a new object threat detection (such as via one or more object sensors of the vehicle). Then, at 524 , control compares the location of the new object threat to the boundary region.

[0094] If the location of the new object threat is within the boundary region at 528 , control proceeds to 532 to disable automatic braking and alarms to avoid subsequent RVB events. Control then returns to 516 to continue monitoring the location of the target relative to the movement of the vehicle.

[0095] If the location of the new object threat is not within the boundary region at 528 , control proceeds to 536 to automatically apply vehicle braking and generate a new RVB alert. Then, at 540 , control determines the location of the newly detected target threat and returns to 512 to define a new boundary region for the newly detected target threat.

[0096] Figure 6 is a flow chart depicting an example process for dead reckoning the position of an object threat relative to the motion of a vehicle. The process may be performed by, for example, Figure 1 The vehicle control module 20 is executed. At 604, the vehicle control module is configured to obtain the position of the detected object threat.

[0097] At 608, the vehicle control module is configured to estimate the changed position of the vehicle using dead reckoning. Example equations for executing a dead reckoning algorithm to estimate the position of the host vehicle are provided below:

[0098] Main vehicle heading angle h: h+W z *dt

[0099] Host vehicle x position h x :h x +cos(h)*dx+sin(h)*dy

[0100] Host vehicle y position h y :h y +sin(h)*dx+cos(h)*dy

[0101]

[0102] Then, at 612, control transforms the coordinates of the position of the target threat relative to the estimated new position of the vehicle (e.g., due to the dead reckoning vehicle position update). The equation for transforming the position coordinates of the detected target threat to a new coordinate system based on the dead reckoning of the vehicle position is provided below:

[0103]

[0104] At 616 , the vehicle control module is configured to report updated coordinates of the object threat location relative to the vehicle.

[0105] Figure 7 is a flow chart depicting an example process for adjusting and attenuating a boundary region of a detected object threat over time. The process may be performed by, for example, Figure 1 The vehicle control module 20 is executed. At 704, an RVB event occurs.

[0106] At 708 , the vehicle control module is configured to determine locations for the plurality of detected object threats. Then, at 712 , control defines a plurality of boundary regions, each boundary region corresponding to a different object threat.

[0107] At 716 , the vehicle control module is configured to monitor the movement of the vehicle along the path trajectory. If the vehicle crosses the TTC threshold of any of the plurality of detected object threats at 720 , control proceeds to 724 to suspend attenuation of the boundary region corresponding to the object threat whose TTC threshold was crossed.

[0108] If the vehicle has not crossed any TTC threshold at 720, control proceeds to 728 to determine whether the boundary area time period has been exceeded. If so, control proceeds to 732 to increase the size of the boundary area for each of the plurality of detected threat objects. An example set of equations for adjusting the size of the boundary area is provided below:

[0109] C-confidence factor, C = ∑(S x *k x ),in and k x -cal weight assigned to each individual sensor N0 is the initial size of the area that will be attenuated

[0110] N(t) is the area that remains after time t and has not decayed

[0111] If control determines at 728 that the boundary area time period has not been exceeded, control proceeds to 736 to determine whether the decay time period has been exceeded for any of the plurality of detected target threats. If so, control proceeds to 740 to stop tracking the corresponding object threat. The vehicle control module is configured to then return to 716 to continue monitoring the movement of the vehicle with respect to the plurality of detected object threats.

[0112] In some example embodiments, a vehicle object detection sensor may be characterized via a sensor characterization process. For example, N tests may be run at a standardized target with a set of repeating speeds and path curvatures, and observations recorded.

[0113] The data association circle can be established through statistical analysis of sensor performance. In some example embodiments, the covariance of the (x, y) pair can be determined over N observations according to the following equation:

[0114]

[0115] where p(x,y)pmf of(X,Y).

[0116] The system can be designed to select an acceptable balance between false detections versus missed detections to establish calibration parameters (such as a table for production use). This can allow for setting a maximum (max) R value for the data association circle of the vehicle object detection sensor. In various implementations, the example boundary area distances, specified time periods, etc. described herein can have calibratable thresholds.

[0117] The foregoing description is essentially merely illustrative and is by no means intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in a variety of forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because after studying the drawings, the specification and the appended claims, other modifications will become clear. It should be understood that one or more steps in the method can be performed in different orders (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in the features of any other embodiment and / or implemented in combination with the features of any other embodiment, even if the combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and the replacement of one or more embodiments with each other is still within the scope of the present disclosure.

[0118] Spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms including: "connected," "engaged," "coupled," "adjacent," "near," "on top," "above," "below," and "disposed." Unless explicitly described as "direct," when describing a relationship between a first and a second element in the above disclosure, the relationship may be a direct relationship in the absence of other intervening elements between the first and second elements, but may also be an indirect relationship in the presence of one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase at least one of A, B, and C should be interpreted to mean a logical (A or B or C), using a non-exclusive logical or, and should not be interpreted to mean "at least one of A, at least one of B, and at least one of C."

[0119] In a diagram, the direction of the arrow, as indicated by the arrow, generally indicates the flow of information (such as data or instructions) of interest for the diagram. For example, when element A and element B exchange various information but the information transmitted from element A to element B is relevant to the diagram, the arrow may point from element A to element B. This unidirectional arrow does not mean that no other information is transmitted from element B to element A. In addition, for information sent from element A to element B, element B may send a request or receipt confirmation to element A for the information.

[0120] In this application, including the definitions below, the term "module" or the term "controller" may be replaced with the term "circuit". The term "module" may refer to, be part of, or include: an application specific integrated circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components that provide the functionality; or a combination of some or all of the above, such as in a system on a chip.

[0121] The module may include one or more interface circuits. In some examples, the interface circuit may include a wired or wireless interface connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module of the present disclosure may be distributed in multiple modules connected via the interface circuit. For example, multiple modules may allow load balancing. In another example, a server (also referred to as a remote or cloud) module may complete some functionality on behalf of a client module.

[0122] The term code as used above may include software, firmware, and / or microcode, and may refer to programs, routines, functions, classes, data structures, and / or objects. The term shared processor circuit includes a single processor circuit that executes some or all code from multiple modules. The term group processor circuit includes a processor circuit that, in combination with additional processor circuits, executes some or all code from one or more modules. References to multiple processor circuits include multiple processor circuits on discrete dies, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term shared memory circuit includes a single memory circuit that stores some or all code from multiple modules. The term group memory circuit includes a memory circuit that is combined with additional memory to store some or all code from one or more modules.

[0123] The term memory circuit is a subset of the term computer-readable medium. The term computer-readable medium as used herein does not include transient electrical or electromagnetic signals propagated through a medium (such as on a carrier wave); therefore, the term computer-readable medium may be considered to be tangible and non-transitory. Non-limiting examples of non-transitory tangible computer-readable media are non-volatile memory circuits (such as flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (such as static random access memory circuits or dynamic random access memory circuits), magnetic storage media (such as analog or digital magnetic tape or hard disk drives), and optical storage media (such as CDs, DVDs, or Blu-ray discs).

[0124] The apparatus and methods described in this application may be implemented in part or in whole by a special-purpose computer, which is created by configuring a general-purpose computer to perform one or more specific functions embodied in a computer program. The functional blocks, flow chart components and other elements described above serve as software specifications, which can be translated into computer programs by routine work of a skilled technician or programmer.

[0125] The computer program includes processor executable instructions stored on at least one non-transitory tangible computer readable medium. The computer program may also include or rely on stored data. The computer program may include a basic input / output system (BIOS) that interacts with the hardware of the special-purpose computer, device drivers that interact with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0126] A computer program may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated by a compiler from source code; (iv) source code executed by an interpreter; (v) source code compiled and executed by a just-in-time compiler, etc. By way of example only, source code may be written using syntax from a language including: C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Fortran, Perl, Pascal, Curl, OCaml, HTML5 (Hypertext Markup Language Fifth Revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Visual Lua, MATLAB, SIMULINK, and

Claims

1. A method for automated vehicle braking control, the method comprising: detecting, by at least one vehicle sensor, a first object threat in a reverse travel path of the vehicle; monitoring a distance between the vehicle and the first object threat relative to a time-to-collision threshold; in response to a determination that the vehicle is crossing a time threshold to a collision, initiating a first rear virtual bumper event by automatically applying brakes of the vehicle; storing a location of the first object threat; defining a boundary area around the location of the first object threat; After the first rear braking event, detecting, by at least one vehicle sensor, a second object threat in the reverse travel path; comparing the location of the second object threat to the boundary region; and In response to determining that the position of the second object threat is within the boundary region, automatic application of brakes is inhibited to avoid a second rear virtual bumper event.

2. The method according to claim 1, further comprising: generating an audible alert during a first rear virtual bumper event; and Responsive to a determination that the location of the second object threat is within the boundary area, generation of an audible alarm is inhibited.

3. The method according to claim 1, wherein: detecting that a first object threat occurs during a first reverse vehicle movement trajectory of the vehicle; detecting that a second object threat occurs during a second reverse vehicle movement trajectory of the vehicle; and A forward movement trajectory of the vehicle is detected prior to detecting a second object threat. 4 . The method of claim 3 , further comprising updating the position of the boundary region relative to the position of the vehicle at the end of the vehicle's forward movement trajectory using dead reckoning.

5. The method according to claim 1, wherein: The boundary region is defined to have a first radius at a first point in time; The method includes increasing the size of the boundary region to a second radius at a second point in time; and The second time point is a fixed period of time after the first time point.

6. The method of claim 5, further comprising increasing the size of the boundary area to a third radius at a third point in time, The third time point is a fixed period after the second time point.

7. The method according to claim 6, wherein: The fixed period is less than or equal to ten seconds; The first radius is less than or equal to twenty centimeters; The second radius is less than or equal to fifty centimeters; and The third radius is less than or equal to one meter. 8 . The method of claim 1 , further comprising eliminating the boundary region after a specified period of time to allow automatic application of braking in response to detecting a third object threat at a location previously covered by the boundary region.

9. The method according to claim 8, wherein: The specified time period is less than or equal to thirty seconds.

10. The method of claim 8, further comprising restarting the designated time period in response to subsequent detection of another object threat within the boundary area before expiration of the designated time period.

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