Procedure for vehicle positioning feedback

Abstract

Method (200) for calculating the position of a vehicle (100) on a road segment, the method comprising: Equipping the vehicle with at least one vehicle sensor and a control unit (108) in electronic communication with the at least one vehicle sensor, wherein the at least one vehicle sensor comprises a vehicle direction sensor (126) and one or more accelerometers (122), vehicle speed sensors (124) and optical sensors; Receiving (204), by the control unit (108), vehicle property data that correspond to at least one vehicle property from at least one vehicle sensor; Receiving (204), by the control (108), map data corresponding to a vehicle position; Determine (206), by means of the control (108), a lane change status indicating whether the vehicle (100) has performed a lane change maneuver within a calibratable time interval; Calculating (212), by the control (108), the vehicle position using the map data in response to the fact that the vehicle (100) has not performed a lane change maneuver within the calibratable time interval; Calculating (218), by the control (108), the vehicle position using the vehicle property data in response to the fact that the vehicle (100) has performed a lane change maneuver within the calibratable time interval; Calibrating (214) the vehicle direction sensor (126) using the map data in response to the lane change status indicating that the vehicle (100) has not performed a lane change maneuver within the calibratable time interval; and Calibrating the vehicle direction sensor (126) using the vehicle property data in response to the lane change status indicating that the vehicle (100) has performed a lane change maneuver within the calibratable time interval.

Description

INTRODUCTION

[0001] The present invention relates generally to the technical field of vehicles and in particular to methods and systems for providing vehicle positioning feedback with respect to a lane position status of the vehicle.

[0002] Current vehicle navigation techniques use dead reckoning with navigation corrections from the Global Navigation Satellite System (GNSS) and / or map matching. Dead reckoning is the process of calculating a vehicle's current position based on a previously determined position and progressing along a course and known or estimated speed over time. However, dead reckoning sensor types—accelerometers, gyroscopes, wheel counters, etc.—must be calibrated so that the sensors can be used in calculating the vehicle's position. This calibration is currently performed using GNSS data, where available, and map matching. GNSS may become unavailable due to the vehicle's physical environment, such as when driving through dense vegetation or a tunnel.

[0003] Some methods for determining the location of terrestrial vehicles use map alignment as a procedure to correct a vehicle's position or direction determined by dead reckoning. Map alignment is the process of aligning a sequence of real-world coordinates with a digital map. If a vehicle follows a path that corresponds to the road in a digitized road network, the map alignment algorithm can "snap" the vehicle's position onto the digitized road and set its direction to that of the road segment. Setting the map-aligned direction can also be used to calibrate dead reckoning sensors so that, when needed, i.e., during the loss or absence of a GNSS signal, the sensors can be used.However, map alignment can become faulty in situations where the vehicle has changed lanes (a change of direction), but the map alignment process detects that the vehicle is on the road segment without registering the lane change and thus incorrectly adjusts the vehicle's position to match the road segment. This mismatch of the vehicle's direction to the road segment also affects the calibration of the direction sensors, as the system calibrates the sensors assuming that no change of direction has occurred when, in fact, a change has taken place. Using map alignment as a navigation correction during a lane change maneuver can lead to errors in the calibration of the direction sensors because a lane change can be interpreted as a deviation from the direction determined by the mapped road segment.

[0004] A method and a device for determining a current position are known from European Patent EP 2 253 936 A1. US Patent 2007 / 0 124 072 A1 discloses systems, methods, and programs for route guidance. German Patent DE 10 2010 033 729 A1 describes methods and devices for determining the position of a vehicle on a roadway. It is an object of the present invention to provide an improved method for calculating the position of a vehicle on a road segment. SUMMARY

[0005] Accordingly, it is desirable to provide an improved procedure for monitoring a vehicle's position and transmitting information about the vehicle's status in relation to lane boundaries. When this information is coupled with an advanced or automated driving system (ADS) or an advanced driver assistance system (ADAS) and includes maps with lane-level information, the vehicle's position calculation can accurately map the vehicle's position and direction within the lane. Additionally, it is desirable to provide an improved procedure that can accurately inform the position calculation and sensor calibration if the vehicle has deviated from its lane and map matching should not be used to update the position information or calibrate the dead reckoning sensors.Furthermore, an improved method for vehicle position monitoring can be used to eliminate ambiguities when a vehicle has moved from a lane to an exit lane or a ramp. Further desirable features and characteristics of the present invention will become apparent from the following description and claims in conjunction with the accompanying drawings.

[0006] Embodiments according to the present disclosure offer a number of advantages. For example, embodiments according to the present disclosure enable a more accurate determination of a vehicle's position on a roadway with multiple lanes or multiple on- and off-ramps. Embodiments according to the present invention also enable more accurate sensor calibration, which is used for more precise determination of the vehicle's position.

[0007] The aforementioned problem is solved by the subject matter of the independent claim. Advantageous further developments are specified in the dependent claims.

[0008] According to the invention, a method for calculating the position of a vehicle on a road segment is disclosed. The method comprises the steps of equipping the vehicle with at least one vehicle sensor and a controller in electronic communication with the at least one vehicle sensor, wherein the at least one vehicle sensor includes a vehicle direction sensor and one or more accelerometers, vehicle speed sensors, and optical sensors; receiving vehicle property data corresponding to at least one vehicle property from the at least one vehicle sensor; receiving, by the controller, map data corresponding to a vehicle position; and determining, by the controller, a lane change status indicating whether the vehicle has performed a lane change maneuver within a calibratable time interval.Calculating the vehicle position using map data in response to a vehicle that has not performed a lane change maneuver within the calibratable time interval; calculating, by the controller, the vehicle position using vehicle property data in response to a vehicle that has performed a lane change maneuver within the calibratable time interval; calibrating the direction sensor using map data in response to the lane change status indicating that the vehicle has not performed a lane change maneuver within the calibratable time interval; and calibrating the direction sensor using vehicle property data in response to the lane change status indicating that the vehicle has performed a lane change maneuver within the calibratable time interval.

[0009] In some embodiments, the map data includes lane information for a mapped road segment. In some embodiments, the vehicle property data denotes crossing a lane boundary and maintaining a vehicle trajectory within the lane. In some embodiments, the vehicle that did not perform the lane change maneuver includes the vehicle that maintains its trajectory within the lane. In some embodiments, the vehicle that performs the lane change maneuver includes the vehicle that crosses the lane boundary.

[0010] In another, unclaimed aspect, a motor vehicle comprises a vehicle body and a plurality of wheels coupled to the vehicle body; at least one vehicle sensor configured to detect at least one vehicle property; and a controller communicating with the at least one vehicle sensor, the controller being configured to receive vehicle property data corresponding to the at least one vehicle property from the at least one vehicle sensor; receiving map data corresponding to a position of the vehicle; establishing a lane-change status indicating whether the vehicle has performed a lane-change maneuver within a calibratable time interval; and calculating the vehicle position using the map data in response to the vehicle that has not performed a lane-change maneuver within the calibratable time interval.And calculating the vehicle position using vehicle property data in response to the vehicle that performed a lane change maneuver within the calibratable time interval.

[0011] In some embodiments, the at least one vehicle sensor includes a vehicle direction sensor and one or more accelerometers, a vehicle speed sensor, and an optical sensor. In some embodiments, the map data includes lane information for a mapped road segment. In some embodiments, the vehicle property data denotes crossing a lane boundary and maintaining a vehicle trajectory within the lane.

[0012] In some embodiments, calculating the vehicle position using map data includes adjusting the vehicle position to the map data and calibrating the vehicle direction sensor using the map data in response to the lane change status indicating that the vehicle has not completed the lane change maneuver within the calibratable time interval. In some embodiments, calculating the vehicle position using vehicle property data includes updating the vehicle position and calibrating the vehicle direction sensor using the vehicle property data in response to the lane change status indicating that the vehicle has completed the lane change maneuver within the calibratable time interval.

[0013] In yet another, unclaimed aspect, a system for calculating the position of a vehicle on a road segment comprises at least one vehicle sensor configured to detect a vehicle property;And a controller that communicates with the at least one sensor, the controller being configured to receive map data corresponding to a vehicle position, determining a lane change status indicating whether the vehicle has performed a lane change maneuver within a calibratable time interval, and calculating the vehicle position using the vehicle property data in response to the lane change status indicating that the vehicle has performed a lane change maneuver within the calibratable time interval, and otherwise calculating the vehicle position using the map data in response to the vehicle that has not performed a lane change maneuver within the calibratable time interval.

[0014] In some embodiments, the at least one vehicle sensor includes a vehicle direction sensor and one or more accelerometers, a vehicle speed sensor, and an optical sensor. In some embodiments, the map data includes lane information for a mapped road segment. In some embodiments, the vehicle property data denotes crossing a lane boundary and maintaining a vehicle trajectory within the lane.

[0015] In some embodiments, calculating the vehicle position using map data involves adjusting the vehicle position to the map data. In other embodiments, calculating the vehicle position using vehicle property data involves updating the vehicle position based on the vehicle property data.

[0016] In some embodiments, the controller is further configured to calibrate the vehicle direction sensor using map data in response to the lane change status indicating that the vehicle has not performed a lane change maneuver within the calibratable time interval, and to calibrate the vehicle direction sensor using vehicle property data in response to the lane change status indicating that the vehicle has performed a lane change maneuver within the calibratable time interval. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The foregoing and other features of the present disclosure will become clearer from the following description and the accompanying claims in conjunction with the accompanying drawings. With the understanding that these drawings represent only some embodiments according to the disclosure, the disclosure is described with additional specificity and detail by the use of the accompanying drawings. All dimensions disclosed in the drawings or elsewhere herein are for illustrative purposes only. Fig. Figure 1 shows a functional block diagram of a vehicle which includes, among other things, a system for monitoring the vehicle position according to one embodiment. Fig. Figure 2 shows a schematic block diagram of an advanced or automated driving system (ADS) for a vehicle according to one embodiment. Fig. Figure 3 shows a flowchart of a process for monitoring the position of a vehicle and using the vehicle position information to improve sensor calibration, which is associated with the system of Fig. 1 can be implemented according to one embodiment. DETAILED DESCRIPTION

[0018] Embodiments of the present disclosure are described herein. However, it is understood that the disclosed embodiments are merely examples and that other embodiments may take different and alternative forms. The figures are not necessarily to scale; some features may be shown larger or smaller to illustrate the details of certain components. Consequently, the disclosed structural and functional details are to be understood merely as a representative basis to convey to those skilled in the art the various ways in which the present invention may be used. As those skilled in the art will understand, various features shown and described with reference to any of the figures can be combined with features shown in one or more other figures to create embodiments that are not explicitly shown or described.The combinations of features shown provide representative embodiments for typical applications. However, any combinations and modifications of the features that are consistent with the teachings of this disclosure may be desirable for certain applications and implementations.

[0019] Certain terminology may be used in the following description solely for reference purposes. Terms such as "above" and "below," for example, refer to directions in the referenced drawings. Terms such as "front," "rear," "left," "right," "tail," and "side" describe the orientation and / or location of parts of the components or elements within a consistent but arbitrary framework, which are clarified by references to the text and related drawings when describing the components or elements under discussion. Furthermore, terms such as "first," "second," "third," and so on may be used to describe separate components. Such terminology may include the words explicitly mentioned above, as well as derivatives and words of comparable meaning.

[0020] With reference to Fig. Figure 1 shows a motor vehicle 100 according to the present disclosure in schematic form. The motor vehicle 100 comprises a controller, a plurality of sensors, a plurality of control modules, and a plurality of actuators configured to perform various vehicle control tasks, including, but not limited to, monitoring the position of a vehicle, such as the position of vehicle 100 between a set of lane markings or boundaries, updating vehicle position data based on whether a lane change maneuver has been detected within a calibratable time interval, and updating sensor calibration based on a lane change status of the vehicle. Although the figures shown herein represent an example with certain arrangements of elements, additional elements, devices, features, or components may be present in other embodiments.It should be considered that... Fig. 1 is for illustrative purposes only and may not be to scale. In this disclosure, a “vehicle location” or “location” refers to the vehicle’s latitude, longitude, and altitude, and a “vehicle position” or “position” refers to the vehicle’s position on a road segment, for example, the vehicle’s position in a left, right, center, or other lane of a road segment, or the vehicle’s position on an on- or off-ramp.

[0021] Vehicle 100 can be any vehicle from a number of different types of motor vehicles, such as a sedan, a car, a truck, or an SUV. Vehicle 100 can further include one—or a combination of several—from a number of different propulsion systems, such as a gasoline or diesel internal combustion engine, a flex-fuel (FFV) engine (i.e., using a mixture of gasoline and ethanol), an engine powered by a gaseous compound (e.g., hydrogen or natural gas), a combustion / electric hybrid engine, and an electric motor.

[0022] As in Fig. As shown in Figure 1, the vehicle 100 generally comprises a body 102, wheels 104, and a steering system 108. The body 102 is mounted on the chassis (not shown) and essentially encloses the other components of the vehicle 100. The body 102 and the chassis can together form a frame. The wheels 104 are each rotatably coupled to the chassis near a respective corner of the body 102.

[0023] With further reference to Fig. In the embodiment shown, the vehicle 100 also includes a plurality of sensors 120, 122, 124, and 126. In the illustrated embodiment, sensor 122 is an acceleration sensor, sensor 124 is a velocity sensor, and sensor 126 is a direction sensor. Sensor 120 represents other sensors that detect observable states of the vehicle or the vehicle's environment and may include radar, lidar, optical cameras, thermal cameras, ultrasonic sensors, and / or additional sensors. In some embodiments, the vehicle 100 also includes a plurality of actuators 130 configured to receive control commands to control the steering, transmission, throttle, or brakes, or other aspects of the vehicle 100, as discussed in more detail below.

[0024] As shown, the vehicle 100 includes at least one controller 108. While depicted as a single unit for illustrative purposes, the controller 108 may additionally include one or more other "controllers." The controller 108 may include a microprocessor or central processing unit (CPU) that communicates with various types of computer-readable storage devices or media. Computer-readable storage devices or media may include volatile and non-volatile memory in the form of read-only memory (ROM), direct-access memory (RAM), and keep-alive memory (KAM). KAM is persistent or non-volatile memory that can be used to store various operating variables while the CPU is powered off.Computer-readable storage devices or media may be implemented using any number of known storage devices, such as PROMs (programmable read-only memory), EPROMs (electrical PROMs), EEPROMs (electrically erasable PROMs), flash memory, or any other electrical, magnetic, optical, or combined storage devices capable of storing data, some of which represent executable instructions used by the controller 108 in controlling the vehicle.

[0025] The controller 108 is equipped with an advanced or automated drive system (ADS) 110 for automatically controlling various actuators in the vehicle. In an exemplary embodiment, the ADS 110 is configured to control the drive system, transmission, steering system, and wheel brakes of vehicle 100 for vehicle acceleration, steering, and braking, respectively, without human intervention, via a plurality of actuators 130 in response to inputs from a plurality of sensors 120, 122, 124, 126. Although the vehicle 100 in Fig. As illustrated in Figure 1 with the ADS 110 to facilitate autonomous or semi-autonomous operation, the systems and procedures for updating the direction sensor calibration and calculating the vehicle position based on the lane change status described herein can be used as part of a general vehicle navigation system.

[0026] With further reference to Fig. The controller 108 also includes interface hardware 112. The interface hardware 112 can include elements such as a Controller Area Network (CAN) bus interface, analog-to-digital converters, and other hardware drivers used to enable communication between the controller 108 and other components of the vehicle 100, for example, the sensors 120, 122, 124, 126, and the actuators 130. The ADS 110 receives input from the sensors 120, 122, 124, and 126 to determine the vehicle position and uses this information to perform the vehicle position calculation more accurately, as discussed in more detail below.In some embodiments, the controller 108 also includes a lane-change status module 116, which uses information acquired by sensors, such as sensors 120, 122, 124, and 126, to determine whether the vehicle 100 has performed a lane-change maneuver within a calibratable time interval. A mapping database 118, which can be stored in a non-volatile, computer-readable memory medium of the controller 108, provides map and location data used to determine when the vehicle has maintained its current lane and additional information used in calculating the position of the vehicle 100. In some embodiments, the map data stored by the mapping database includes lane information for the mapped road segments. The lane information includes the number of lanes and the position of the lane boundaries of the mapped road segments.The mapping database 118 can also receive information from the ADS 110 to update the map and location information stored in the mapping database 118. In some embodiments, the controller 108 also includes a sensor calibration module 119. The sensor calibration module 119 receives inputs from the plurality of sensors 120, 122, 124, 126 and calibrates the direction sensor 126 using map adaptation algorithms or optical sensor data indicating a vehicle position on the roadway, depending on the lane change status identified by the lane change status system 116. The ADS 110 can output the output 121 from the sensor calibration module 119, as shown in [reference]. Fig. 2 shown, received.

[0027] A Global Navigation Satellite System (GNSS) includes an antenna 132, which is electrically connected to a GNSS receiver 128. The GNSS provides location information (longitude, latitude, and altitude) to the ADS 110. When GNSS information is available, the direction sensor 126 can be calibrated using the direction information contained as part of the navigation information from the GNSS. However, as discussed in more detail below, navigation information may not be available, for example, when a vehicle is traveling through a tunnel or through dense vegetation that obstructs satellite reception.In these scenarios, map matching can be used to calibrate the 126 direction sensor; however, map matching cannot always provide the most accurate direction information, especially if a vehicle has changed its position on a roadway, such as changing lanes or entering and exiting highways. If GNSS information is unavailable, the vehicle's lane-change status can be used to determine whether map matching should be used to perform the direction sensor calibration calculations.

[0028] In some embodiments, the user provides input to the ADS 110 via a user interface 114, which in some embodiments may include a steering wheel, a turn signal, or other user input, to indicate an intended or executed change in the vehicle's direction, such as a lane change maneuver. A power source 127 supplies electrical energy to electrical components of the vehicle 100, including, for example, and without limitation, the GNSS receiver 128 and the controller 108.

[0029] As in Fig. As shown in Figure 2, the ADS 110 incorporates several separate control systems for determining the presence, location, classification, and trajectory of detected features or objects near the vehicle, including monitoring a vehicle's position on a road segment. The ADS 110 is configured to accept inputs such as... Fig. Figure 1 illustrates how the ADS 110 receives and synthesizes sensor inputs from a variety of sensors 120, 122, 124, 126 to generate parameters that are used as inputs for other control algorithms.

[0030] The ADS 110 includes a sensor fusion module 142 for determining the presence, position, and trajectory of the detected features near the vehicle. The sensor fusion module 142 is configured to receive inputs 137 from a variety of sensors, such as those in Fig. The sensor fusion module 142 receives input from the sensors 120, 122, 124, and 126 shown in Figure 1. It processes and synthesizes the inputs from the multitude of sensors and generates a sensor fusion output 144. The sensor fusion output 144 includes various calculated parameters, including the position of a detected obstacle relative to the vehicle, a predicted trajectory of the detected obstacle relative to the vehicle, and the position and orientation of lane markings relative to the vehicle.

[0031] The ADS 110 also includes a mapping and localization module 146 for determining the vehicle's location and course for a current driving cycle. The mapping and localization module 146 is also configured to accept input from a variety of sensors, such as those in Fig. The mapping and localization module 146 receives input from the sensors 120, 122, 124, and 126 shown in the diagram. It processes and synthesizes the inputs from the numerous sensors and generates a mapping and localization output 148. This output includes various calculated parameters, including a vehicle course for the current driving cycle and a current vehicle position relative to that course.

[0032] The mapping and localization module 146 is also configured to receive input from the lane change status module 116. The lane change status module 116 monitors the vehicle's position relative to lane markings or boundaries. Using data from the plurality of sensors 120, 122, 124, 126, the lane change status module 116 can determine a lane change status of the vehicle and generates output 117, which indicates the lane change status of vehicle 100. The lane change status indicates whether vehicle 100 has changed lanes or crossed a lane boundary, maintained a trajectory in a current lane, or if the lane change status is ambiguous or cannot be determined. In some embodiments, the lane change status module 116 can, for example,When a vehicle enters a multi-lane road, the number of lane markings crossed by the vehicle is also "counted" to determine the vehicle's lane. Additionally, the Lane Change Status Module 116 can distinguish between a vehicle crossing a lane marking during an intentional lane change and a vehicle simply deviating from the lane marking by, for example, monitoring the time between lane marking crossings and / or crossings of the left and right lanes. The Lane Change Status is a calculated parameter used by the Mapping and Localization Module 146 to determine the vehicle's position on the road segment.Additionally, the lane change status is used to supplement the sensor data provided by the multiple sensors 120, 122, 124, and 126 to determine the vehicle's position more accurately and reduce positional deviation. If the lane change status module 116 detects that the vehicle has changed lanes 100 times, the mapping and localization module 146 does not use a map alignment process to "snap" the vehicle to a road segment, as map alignment procedures can lead to position calculation errors in this scenario. Furthermore, using map alignment to determine the vehicle's position can lead to calibration errors in the vehicle direction sensors, since the lane change maneuver is interpreted by the system as a deviation from the direction of the mapped road segment. Fig. Figure 3, which is discussed below, illustrates a procedure that incorporates the lane change status to determine a vehicle's position more accurately and to improve the calibration of the direction sensors.

[0033] The ADS 110 also includes a path planning module 152 for determining a vehicle path to follow in order to keep the vehicle on the desired course while complying with traffic regulations and avoiding any detected obstacles. The path planning module 152 uses, for example, but is not limited to, a first obstacle avoidance algorithm configured to avoid any detected obstacles near the vehicle, a first lane maintenance algorithm configured to keep the vehicle in its current lane, and a first course maintenance algorithm configured to keep the vehicle on the desired course. The path planning module 152 is configured to receive the sensor fusion output 144 and the mapping and localization output 148.The path planning module 152 processes and synthesizes the sensor fusion output 144 and the mapping and localization output 148, generating a path planning output 154. The path planning output 154 includes an assigned vehicle course based on the vehicle route, the vehicle position relative to the route, the position and orientation of the lanes, and the presence and trajectory of any detected obstacles.

[0034] The ADS 110 also includes a vehicle control module 156 for issuing control commands to vehicle actuators. The vehicle control module uses a first distance algorithm to calculate a vehicle distance resulting from a given set of actuator settings. The vehicle control module 156 is configured to receive the route planning output 154. The vehicle control module 156 processes the route planning output 154 and generates a vehicle control output 158. The vehicle control output 158 ​​contains a set of actuator commands to execute the instructed distance from the vehicle control module 156, including, but not limited to, a steering command, a shift command, a throttle command, and a brake command.

[0035] The vehicle control output 158 ​​is transmitted to the actuators 130. The actuators 130 receive control signals from the controller 108 to control steering, braking, throttle, or other aspects of the vehicle 100. In an exemplary embodiment, the actuators 130 include a steering control, a shift control, a throttle control, and a brake control. The steering control can, for example, control a steering system of vehicle 100. The shift control can, for example, control a transmission of vehicle 100. The throttle control can, for example, control a drive system of vehicle 100. The brake control can, for example, control the wheel brakes of the wheels 104 of vehicle 100.

[0036] While the vehicle 100 as in Fig. Figure 1 shows that the vehicle contains ADS 110. However, the vehicle 100 may not contain ADS 110, but instead a navigation system that receives input 117 from the lane change status module 116 to perform the vehicle position calculation discussed above. Additionally, the sensor calibration module 119 can also supply input 121 to the vehicle navigation system to calibrate the direction sensor 126 depending on the lane change status.

[0037] Fig. Figure 3 illustrates a method 200 that includes lane change status information as feedback and additional information used in vehicle positioning calculations to improve vehicle position accuracy and direction sensor calibration. The method 200 can be used in conjunction with the vehicle 100, the controller 108, and the various modules of the ADS 110 according to exemplary embodiments. The sequence of operations within the method 200 is not limited to those shown in Figure 3. Fig. The sequential processing shown in section 3 is limited, but can, where applicable, be carried out in one or more different sequence(s) in accordance with the present disclosure.

[0038] Starting at 202, as in Fig.As shown in Figure 3, the procedure proceeds to step 204. In step 204, the controller 108 receives sensor data from a variety of vehicle sensors, such as sensors 120, 122, 124, and 126, and also receives navigation data indicating the vehicle's position from a navigation data receiver, such as the GNSS receiver 128, if available. Additionally, in step 204, the controller 108 accesses map data from the map information database 118. In some embodiments, the map data may also include the mapping and localization output 148, which is determined as a result of calculations performed by the mapping and localization module 146 of the ADS 110. In step 206, the controller 108 processes the sensor data, GNSS data, and map data to determine the lane change status.The lane change status indicates whether the vehicle has changed lanes (100), maintained its course within the lane, or whether the lane change status is unknown or ambiguous. Lane change detection and determination of the lane change status can be performed, for example, without limitation, by the lane change status module 116 using data from the numerous sensors 120, 122, 124, and 126. The lane change status is stored in a non-volatile, computer-readable storage medium at 208 and evaluated at 210.

[0039] If the lane change status at decision point 210 indicates that the vehicle has maintained its current lane, procedure 200 proceeds to step 212, and the controller 108 calculates the vehicle's position using, for example, the mapping and localization module 146, based on the directional information obtained from the current map data. In this scenario, the current map data provides accurate information for determining the vehicle's position because the vehicle has not changed direction from the road, such as by changing lanes or entering or exiting a highway, which could lead to an inaccurate determination of the vehicle's position on the road segment.

[0040] Procedure 200 proceeds to step 214, and the controller 108 calibrates the direction sensor based on the map data. In the absence of GNSS data, direction sensors, such as direction sensor 126, are used to calculate the vehicle's direction. A dead reckoning sensor receives direction information from the GNSS, if present, or from the map reconciliation using map data. In the absence of GNSS data, and if the vehicle has not performed a lane change maneuver within a calibratable time interval, the map reconciliation provides an accurate input for the direction sensor calibration calculation. Since no lane change has occurred, the map data at step 214 is the most accurate indicator of the vehicle's direction.Therefore, the vehicle direction calculated by the vehicle sensor can be compared or aligned with the direction provided by the map data, and calibration parameters can be calculated for the direction sensor to more accurately calibrate the vehicle sensor 126. Procedure 200 then proceeds to step 216 and ends.

[0041] However, if in step 210 the lane change status indicates that the vehicle has performed a lane change maneuver within a calibratable time interval, or if the lane change status is unknown or ambiguous, procedure 200 proceeds to step 218, and the controller calculates the vehicle position based on the information provided by the lane change status module 116 and one or more of the plurality of sensors 120, 122, 124, 126. Because the vehicle direction has diverged from the road direction, for example, if a lane change has occurred or if the lane change status module 116 determines that the vehicle's lane change status is ambiguous, the navigation data, if available, and the vehicle sensor data are more accurate indicators of the vehicle's direction than the map data.If no GNSS data is available and map adjustment is not applicable due to a lane change maneuver, the direction sensor 126 can be calibrated using the last calibration settings. Using the last settings avoids unnecessary and potentially inaccurate calibration of the direction sensor 126, since the lane change is treated as a deviation from the direction of the mapped road segment. Afterward, procedure 200 ends at 216.

Claims

[1] A method (200) for calculating a position of a vehicle (100) on a road segment, the method comprising: Equipping the vehicle with at least one vehicle sensor and a controller (108) in electronic communication with the at least one vehicle sensor, wherein the at least one vehicle sensor comprises a vehicle direction sensor (126) and one or more of an accelerometer (122), a vehicle speed sensor (124), and an optical sensor; Receiving (204), by the controller (108), vehicle characteristic data corresponding to at least one vehicle characteristic from the at least one vehicle sensor; Receiving (204), by the controller (108), map data corresponding to a vehicle position; Determining (206), by the controller (108), a lane change status indicating whether the vehicle (100) has performed a lane change maneuver within a calibratable time interval; calculating (212), by the controller (108), the vehicle position using the map data in response to the vehicle (100) not having performed a lane change maneuver within the calibratable time interval; Calculating (218), by the controller (108), the vehicle position using the vehicle characteristic data in response to the vehicle (100) having performed a lane change maneuver within the calibratable time interval; Calibrating (214) the vehicle direction sensor (126) using the map data in response to the lane change status indicating that the vehicle (100) has not performed a lane change maneuver within the calibratable time interval; and Calibrating the vehicle direction sensor (126) using the vehicle characteristic data in response to the lane change status indicating that the vehicle (100) has performed a lane change maneuver within the calibratable time interval. [2] The method of claim 1, wherein the map data includes lane information of a mapped road segment. [3] The method of claim 2, wherein the vehicle characteristic data indicates crossing a lane boundary of a traffic lane and maintaining a vehicle trajectory within the traffic lane. [4] The method according to claim 3, wherein in the event that the vehicle (100) has not performed the lane change maneuver, the vehicle (100) maintains the vehicle trajectory within the lane. [5] Method according to claim 3, wherein in the event that the vehicle (100) has performed the lane change maneuver, the vehicle (100) crosses the lane boundary of the traffic lane. [6] The method of claim 1, wherein calculating the vehicle position using the map data comprises matching the vehicle position with the map data. [7] The method of claim 1, wherein calculating the vehicle position using the vehicle characteristic data comprises updating the vehicle position using the vehicle characteristic data.

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