Dynamic determination of vehicle pitch

Abstract

A method for determining vehicle pitch includes a first operating state defined by a vehicle exceeding a speed threshold, during which a plurality of inputs are used to determine an absolute pitch. The pitch can be calculated by integrating longitudinal acceleration measurements to estimate a distance-averaged global attitude of the longitudinal acceleration measurements, taking into account contributions from vehicle speed due to slope and changes in average gravitational acceleration. This method further includes a second operating state defined by the vehicle falling below the speed threshold, during which a plurality of inputs are used to determine a relative vehicle pitch.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of U.S. Provisional Application No. 63 / 367,586, filed on July 1, 2022, entitled "DYNAMICALLY DETERMINING VEHICLE PITCH", which is hereby incorporated by reference in its entirety.

Background Art

[0002] Generally speaking, various vehicles such as electric vehicles, combustion engine vehicles, hybrid vehicles, etc. can be composed of various control components configured to facilitate operation. More specifically, a vehicle can include one or more control components that utilize measured or estimated vehicle pitch to adjust the operation of the vehicle or otherwise set operating parameters associated with vehicle components. Exemplarily, one such control component can include a component capable of causing a modification to the operation of a headlight based on the measured or estimated vehicle pitch. Specifically, in one aspect, the control component can correspond to a headlight leveling control that can modify the position of the vehicle headlight so as to maintain the intersection angle of the light with respect to the plane of the road surface.

[0003] Vehicles can often include hardware and software features that facilitate location services, or can access computing devices that provide location services. For example, control components on a vehicle can be configured to utilize external information sources such as a Global Positioning System (GPS) source, a Wireless Local Area Network (WLAN) access point information source, a Bluetooth information source, a Radio Frequency Identification (RFID) source, and other available location information to determine an approximate location of the vehicle. Additionally, the vehicle can include a navigation system or an access navigation component that can generate information related to navigation information or direction information provided to vehicle occupants and users.

Summary of the Invention

[0004] In some aspects, the techniques described herein are a method for determining vehicle pitch for a plurality of vehicle operating states, the method comprising: obtaining a first set of inputs corresponding to a first operating state of the vehicle, the first set of inputs corresponding to first operating information including position information, longitudinal acceleration sensor information, and at least one additional vehicle operating parameter; calculating an absolute vehicle pitch based on the first operating information, the calculating of the absolute vehicle pitch being based on at least two separate position measurements; storing the absolute vehicle pitch; determining that the vehicle has fallen below a vehicle speed threshold; obtaining a second set of inputs corresponding to a second operating state of the vehicle, the second set of inputs corresponding to second operating information including longitudinal acceleration sensor information; determining that the vehicle is characterized as being likely to transition from the second operating state to the first operating state; obtaining a third set of inputs corresponding to a third operating state of the vehicle, the third set of inputs corresponding to third operating information including updated longitudinal acceleration sensor information; determining a relative vehicle pitch change based on processing the second operating information and the third operating information; and storing the relative vehicle pitch change together with the absolute vehicle pitch.

[0005] In some aspects, the techniques described herein are a method for determining a vehicle pitch of a vehicle, the method comprising obtaining a first location sensor input corresponding to a first measurement of a location, obtaining a first motion sensor input corresponding to the first measurement of the location, obtaining a second location sensor input corresponding to a second measurement of the location, obtaining a second motion sensor input corresponding to the second measurement of the location, and determining the vehicle pitch based at least in part on the first location sensor input, the second location sensor input, the first motion sensor input, and the second motion sensor input.

[0006] In some aspects, the techniques described herein are a system for determining a vehicle pitch of a vehicle, the system comprising a GPS signal receiver, an accelerometer, a speed sensor, and a processing component, the processing component being configured to receive from the GPS signal receiver a first altitude input corresponding to a first measurement of a location, receive from the accelerometer and the speed sensor a first motion sensor input corresponding to the first location measurement, receive from the GPS signal receiver a second altitude sensor input corresponding to a second measurement of the location, receive from the accelerometer and the speed sensor a second motion sensor input corresponding to the second location measurement, and determine the vehicle pitch based at least in part on the first altitude input, the second altitude input, the first motion sensor input, and the second motion sensor input. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] These and other features, aspects, and advantages of the present invention will be described herein with reference to the drawings of preferred embodiments intended to illustrate, and not to limit, the present invention.

[0008]

Figure 1

[0009]

Figure 2

[0010]

Figure 3A

[0011]

Figure 3B

[0012]

Figure 3C

[0013]

Figure 4

Mode for Carrying Out the Invention

[0014] Generally speaking, one or more aspects of the present disclosure relate to the configuration and dynamic calculation of vehicle pitch based on various operating states of a vehicle. As an exemplary example, aspects of the present application relate to the utilization of inputs from various combinations of a longitudinal acceleration detection system, a location or navigation system, or vehicle motion sensors for determining vehicle pitch according to the operating state of the vehicle. Exemplarily, the dynamic calculation of vehicle pitch is determined without input from any physical measurement pitch, such as a physical sensor capable of measuring and recording vehicle pitch relative to the road plane.

[0015] According to an aspect of the present application, for an operation parameter related to a vehicle speed exceeding a threshold, a vehicle pitch processing component processes inputs from a longitudinal acceleration detection system, a location or navigation system, a vehicle motion sensor that measures wheel speed, and other sensors / values to determine the vehicle pitch. In another aspect of the present application for a vehicle speed below a threshold where location processing information cannot be used to determine the vehicle pitch, the vehicle pitch processing component processes inputs from an acceleration detection system and vehicle motion sensor measurements and other sensors / values to determine a change in the vehicle pitch based on a previously determined vehicle pitch. By way of example, the acceleration detection system can include a longitudinal acceleration system. Thus, the vehicle pitch processing component can determine the vehicle pitch for multiple operating states of the vehicle without the need from a certain class of physical sensors, detection systems, or other components that directly measure suspension system displacement and are used to determine the vehicle pitch relative to the road surface. Such a class of physical sensors or detection systems is often referred to as a "ride height sensor".

[0016] Generally speaking, vehicle pitch can be utilized as an input to a control system associated with the vehicle. In one aspect, the vehicle pitch can be an input for controlling components associated with headlight leveling in order to maintain the angle of light provided from one or more headlight components of the vehicle relative to the current road surface. The control component can utilize a motor or other control device to adjust the headlight components based on the vehicle pitch (e.g., vertical adjustment of at least a portion of the headlight components). In another aspect, the vehicle pitch can be an input for controlling components associated with or used to facilitate headlight aiming in order to establish the vertical and horizontal angle / aiming of the light provided from one or more headlight components of the vehicle relative to the current road surface. The headlight aiming settings / parameters can be set during manufacturing, prior to distribution, during vehicle servicing, or in accordance with customer input / adjustment.

[0017] Conventionally, a vehicle has been associated with a physical sensor capable of measuring the vehicle pitch relative to the current road plane. Such a physical sensor is typically configured to determine the vehicle pitch during operation, including measurements of the vehicle pitch while the vehicle is moving (e.g., above a speed threshold), while the vehicle is substantially stationary (e.g., below a speed threshold), or during an alternative definition of movement. Nevertheless, the physical sensor components correspond to additional costs for vehicle manufacturing. Additionally, such physical sensors may be subject to failure, the need for replacement, or upgrade. Additionally, the physical mounting of the sensing system or sensor components may require customization according to the physical attributes of different vehicle manufacturers, models, or features.

[0018] As described above, a vehicle may include several sensors, processing components, and input sources that may have one or more functions. For example, a navigation system and a location system may be configured to generate navigation information or direction information. A vision system may provide object detection that can assist in semi-autonomous driving functions, autonomous driving functions, or safety systems. Such systems are not independently configured to provide such functions associated with the automatic determination of vehicle pitch during vehicle operation above a speed threshold (e.g., a first operating state also known as a driving cycle or driving state), the automatic determination of vehicle pitch during vehicle operation below a speed threshold (e.g., a second operating state also known as a parking cycle or parking state), or a combination thereof. Additionally, to some extent, a vision system may be configured to attempt to determine vehicle pitch, and such systems are typically associated with high power consumption and insufficient accuracy in pitch estimation.

[0019] To address at least some of the above deficiencies, aspects of the present application are directed to the use of a combined set of inputs from an integrated sensor or sensing system, a location system, and a navigation system that is integrated to determine vehicle pitch as a function of sensor inputs. Aspects of the present application are directed to the use of a combined set of inputs from an integrated sensor or sensing system and a location system that is integrated to characterize an event to determine a vehicle pitch above a speed threshold (e.g., a first operating state of the vehicle). The determined vehicle pitch can be regarded as an absolute vehicle pitch. Such determination can further include an automated or automated process or generation of a control signal based on the determined vehicle pitch, such as activation of a control component for leveling the headlights.

[0020] Exemplarily, a vehicle can include a vehicle pitch processing component that acquires and processes a set of inputs associated with the operation of the vehicle during a first operating state, including acceleration information (e.g., longitudinal acceleration value(s)), road gradient information, and wheel speed information. Exemplarily, the acceleration information is collected from an acceleration sensor or acceleration sensing system (e.g., a longitudinal acceleration sensor or longitudinal acceleration system). Additionally, the road gradient information can be provided or calculated, for example, based on positioning and navigation system information, such as a road gradient based on known altitude information. Further, the wheel speed information can be provided or calculated, for example, based on a wheel speed sensing system or sensor. In some embodiments, the longitudinal sensor(s), the positioning and navigation system, and the wheel speed sensor(s) all correspond to components and functionality having one or more other functions in the operation of the vehicle. As described herein, the vehicle pitch processing component calculates an absolute vehicle pitch value (or values) as a function of the set of inputs.

[0021] Other aspects of the present application correspond to the use of a combined set of inputs from a sensor or sensing system and a location system integrated to characterize an event to determine a vehicle pitch below a speed threshold (e.g., a second operating state of the vehicle). The determined vehicle pitch can be considered a relative vehicle pitch based on an absolute vehicle pitch previously determined during a first operating state of the vehicle. Such determination can further include an automatic or automated processing or generation of a control signal based on the determined vehicle pitch, such as activation of a control component for leveling the headlights.

[0022] Exemplarily, the vehicle can include a vehicle pitch processing component that obtains and processes a set of inputs associated with the operation of the vehicle during a second operating state, including acceleration information (e.g., acceleration value(s)), and an additional sensor(s) or sensor system that can be utilized as a trigger event as described herein. As described above, the acceleration information is collected from a longitudinal sensor or sensing system. For purposes of the present application, the vehicle can be associated with any number of acceleration values measured during operation. Thus, reference to acceleration information can be associated with the selection of one or more instances of the measured acceleration information. Such collected information is generally referred to as "first," "second," etc. for purposes of clarifying the number of measurements or the plurality of measured acceleration values. The vehicle pitch processing component can associate the last absolute vehicle pitch with a second longitudinal acceleration value(s) when the vehicle enters the second operating state. Thereafter, when the vehicle pitch processing component processes the sensor input or, alternatively, receives information corresponding to a trigger event (e.g., exceeding a speed threshold, activation of a propulsion system, detected movement, door lock, etc.) that can characterize that the vehicle may be resuming the first operating state, the vehicle pitch processing component obtains an updated acceleration value (e.g., a third longitudinal acceleration value) measured at the time of the trigger event. The vehicle pitch processing component can then determine a change in vehicle pitch based on processing the first and second longitudinal acceleration values.

[0023] Although various aspects will be described in accordance with exemplary embodiments and combinations of features, those skilled in the art will understand that the examples and combinations of features are exemplary in nature and should not be construed as limiting. More specifically, aspects of the present application may be applicable to various types of vehicles, including vehicles having different propulsion systems such as compound engines, hybrid engines, and electric engines. Even further, aspects of the present application may be applicable to various types of vehicles that can incorporate different types of sensors, sensing systems, navigation systems, or location systems. For example, in some embodiments, aspects of the present application may be implemented without any input from a navigation system. Similarly, aspects of the present application may be combined with or implemented with other types of components that can facilitate the operation of the vehicle, including autonomous driving applications, driver convenience applications, and the like.

[0024] FIG. showing an environment corresponding to the automatic determination of vehicle pitch according to one or more aspects of the present application. The environment includes a set of local sensor inputs that can be utilized to enable a vehicle pitch processing component 110 to automatically determine vehicle pitch during various operating states of the vehicle, such as an operating state characterized or defined by a speed threshold. The set of local sensors 120 can include one or more sensors or sensor-based systems that are included with the vehicle or otherwise accessible by the vehicle during operation. The local sensors 120 or sensor system 120 may be integrated into the vehicle. Alternatively, the local sensors or sensor system may be provided by an interface associated with the vehicle, such as a physical connection, a wireless connection, or a combination thereof.

[0025] In one aspect, the local sensor can include one or more positioning systems that can obtain reference information from external sources that enable various levels of accuracy when determining the positioning information of the vehicle. For example, the positioning system can include various hardware and software components for processing information from various sources. Exemplary examples include, but are not limited to, information from a GPS source, a wireless local area network (WLAN) access point information source, a Bluetooth information source, a radio frequency identification (RFID) source, etc. In some embodiments, the positioning system can obtain a combination of information from multiple sources. Exemplarily, the positioning system can obtain information from various input sources and determine the positioning information about the vehicle, specifically the altitude at the current location. In other embodiments, the positioning system can also determine movement-related operation parameters such as the direction of movement, speed, acceleration, etc. The positioning system may be configured as part of the vehicle for multiple purposes including, for example, autonomous driving applications, extended driving, or user-assisted navigation. Exemplarily, the positioning system can include processing components and data 124 that facilitate the identification of various vehicle parameters as described herein.

[0026] In yet another aspect, the local sensor can include one or more navigation systems for identifying navigation-related information. Exemplarily, the navigation system can obtain positioning information from a positioning system and identify characteristics or information about the identified location, such as altitude, road gradient, etc. The navigation system or other vehicle systems can further obtain altitude information by searching or comparing the location information with known altitude information associated with a map or database. The navigation system can also identify the proposed or intended lane location in a multi-lane road based on the direction provided or expected for the vehicle user. Similar to the location system 130, the navigation system 126 can be configured as part of the vehicle for multiple purposes, including autonomous driving applications, extended driving, or user-assisted navigation. The navigation system can be combined with or integrated into the positioning system. Exemplarily, the navigation system can include processing components and data that facilitate the identification of various vehicle parameters as described herein. As previously identified, in some embodiments, the input from the navigation system may be omitted or otherwise not utilized.

[0027] Local resources may further include vehicle pitch processing components that can be hosted on a vehicle or a computing device accessible by the vehicle (e.g., a mobile computing device). The vehicle pitch processing components can, by way of example, access inputs from various local sensors or sensor systems and process the input data as described herein. The vehicle pitch processing components can, by way of example, process inputs from a combination of a positioning system, a navigation system, and other vehicle operating parameters to dynamically calculate the vehicle pitch during multiple operating states of the vehicle. More specifically, the vehicle pitch processing components can determine the vehicle pitch as a function of sensor inputs during a first operating state corresponding to a vehicle speed above a threshold. The speed threshold can correspond to a vehicle speed for a minimum time above a minimum speed that can be characterized as a sustained state of vehicle motion sufficient to utilize position information. The minimum speed threshold and the time threshold can be determined dynamically based on criteria such as position signal availability (e.g., GPS signal strength), historical information, etc. The vehicle pitch processing components can determine the vehicle pitch as a function of sensor inputs during a second operating state corresponding to a vehicle speed below the threshold. In this embodiment, some conventional approaching vehicle pitch determination methods based on position and navigation information may not be available.

[0028] The environment can further include various additional sensor components or sensing systems operable to provide information regarding various vehicle operating parameters for use in determining vehicle pitch according to one or more of the operating states. Exemplarily, in one embodiment, the additional sensor components can include sensors for measuring or determining the longitudinal acceleration of the vehicle. The longitudinal acceleration input can be utilized to determine vehicle pitch during the first and second operating states, as discussed herein. In another embodiment, the additional sensor components can include sensors for measuring or determining wheel speed for use in determining vehicle pitch during the first operating state. In another embodiment, the additional sensor components can include sensors for measuring or determining when the vehicle can transition from the second operating state to the first operating state, such as transmission status, ignition status, seatbelt fastening, parking brake status, selection of a navigation destination, audible input, status of latches / locks associated with doors, trunks, or other access points. The transmission status can be understood as information regarding whether the vehicle is in park, drive, or reverse. Although some electric vehicles do not require a transmission, they still have park, drive, and reverse statuses, so the transmission status does not require transmission components. The ignition status can be understood as whether the vehicle is off, on but not in a driving state, or the vehicle is on and driving, where driving is associated with a drive or reverse transmission status. The door status can include the status of latches / locks associated with doors, trunks, or other access points. The door status can be information such as whether a door, trunk, or lid is open or closed. It should be understood that the sensors related to status determination can be individual sensors or sensors integrated into various components related to each state, such as the latch or lock function of the vehicle door used to determine that the door is in a closed state.Furthermore, it should be understood that other components can, for example, determine the status of the transmission, so there is no need for a specific sensor associated with the status sensor.

[0029] The environment can further include one or more control components 122 for processing the output from the vehicle pitch processing component 110. In one embodiment, the control component 122 can include a control component for the headlight leveling function, at least partially based on the output from the vehicle pitch processing component. In another embodiment, the control component 122 can include a control component for the headlight aiming function, at least partially based on the output from the vehicle pitch processing component. Other embodiments of the control component 122 can include, but are not limited to, a suspension control component, a collision avoidance component, etc. As described above, by way of example, headlight leveling can be utilized to maintain the angle of light provided from one or more headlight components of the vehicle with respect to the current road surface. The control component 122 can utilize a motor or other control device to adjust the headlight components based on the vehicle pitch (e.g., vertical adjustment of at least a portion of the headlight components). Also, as described above, headlight aiming can be utilized to establish the vertical and horizontal angles / aiming of the light provided from one or more headlight components of the vehicle with respect to the current road surface. The headlight aiming settings / parameters can be set during manufacturing, before distribution, during vehicle servicing, or according to customer input / adjustment.

[0030] Next, referring to FIG. 2, an exemplary architecture for implementing vehicle pitch processing components on one or more local resources or network services will be described. The vehicle pitch processing components may be part of a component / system that provides functions related to the operation of components such as headlight components, suspension components, etc. In other embodiments, the vehicle pitch processing components may be a stand-alone application that interacts with other components such as local sensors or sensor systems, signal interfaces, etc.

[0031] The architecture of FIG. 2 is exemplary in nature and should not be construed as requiring any particular hardware or software configuration for the vehicle pitch processing components. The general architecture of the vehicle pitch processing component 110 shown in FIG. 2 includes an arrangement of computer hardware and software components that can be used to implement aspects of the present disclosure. As shown, the vehicle pitch processing component 110 can be implemented in a computing environment that includes a processing unit 204, a network interface 206, a computer-readable media drive 207, and an input / output device interface 208, all of which can communicate with each other via a communication bus. The components of the vehicle pitch processing component 110 may be physical hardware components or may be implemented in a virtualized environment. Additionally, in other embodiments, the vehicle pitch processing component 110 may be executed in an embedded system or dedicated component such as a microcontroller, an embedded control unit, etc.

[0032] The network interface 206 can provide connectivity to one or more networks or computing systems, such as the network of FIG. 1. Thus, the processing unit 204 can receive information and instructions from other computing systems or services via the network. The processing unit 204 can also communicate with the memory 250 and further provide output information to an optional display via the input / output device interface 208. In some embodiments, the vehicle pitch processing component 110 can include more (or fewer) components than those shown in FIG. 2, such as those implemented in a mobile device or vehicle.

[0033] Memory 250 may include computer program instructions executed by processing unit 204 to implement one or more embodiments. Memory 250 generally includes RAM, ROM, flash memory, NVRAM, or other persistent or non-transitory memory. Memory 250 can store interface software 252 and an operating system 254 that provides computer program instructions used by processing unit 204 in the general management and operation of vehicle pitch processing component 110. The memory may further include computer program instructions and other information for implementing aspects of the present disclosure. For example, in one embodiment, the memory includes a sensor interface component 256 that obtains information from various sensors or sensing systems such as a navigation system, a position system, a vehicle motion parameter system, etc. The memory further includes a pitch determination component 258 for utilizing sensor inputs to determine vehicle pitch according to various operating states of the vehicle as described herein. Exemplarily, vehicle pitch determination component 258 can be configured to determine vehicle pitch according to different operating states of the vehicle including a first operating state, and the first operating state corresponds to a vehicle speed exceeding a threshold based on exceeding a minimum speed during a minimum amount of time. Exemplarily, a second operating state corresponds to a vehicle speed below the threshold. The memory can further include a control component interface 260 for providing an output to various control components that can utilize the vehicle pitch as an input. Although shown as components combined within vehicle pitch processing component 110, those skilled in the art will understand that one or more of the components within the memory can be implemented in an individualized computing environment that includes both a physical computing environment and a virtual computing environment.

[0034] Next, referring to FIGS. 3A - 3C, a flow diagram of a pitch determination routine 300 and related sub - routine 350 implemented by a vehicle pitch processing component will be described. Illustratively, pitch determination routine 300 represents a general routine for determining vehicle pitch in two or more operating states. Illustratively, the first operating state corresponds to a vehicle speed that exceeds a threshold based on exceeding a minimum speed over a minimum time period. Illustratively, the second operating state corresponds to a vehicle speed that is below (above) the threshold. For purposes of illustration, routine 300 attempts to process vehicle pitch based on the first operating state in parallel with processing vehicle pitch based on the second operating state. The results of the processing along the parallel tracks vary based on the current operating state of the vehicle (as described herein). Illustratively, the operating state of the vehicle and the references to the "first" and "second" operating states are intended to distinguish between two or more scenarios in which one or more measured parameters, such as vehicle speed, are different.

[0035] Considering first the processing of sensor inputs according to the first operating state, blocks 302 - 306 are described. In block 302, the vehicle pitch processing component acquires vehicle motion inputs. As described above, in an exemplary embodiment, the vehicle pitch processing component can process inputs from a combination of positioning parameters corresponding to wheel speeds and vehicle motion parameters. In another aspect, the input can be provided (or requested) by one or more positioning systems that can obtain reference information from external sources that enable various levels of accuracy in determining the positioning information of the vehicle. For example, the positioning system can illustratively include various hardware and software components for processing information from a GPS source. In some embodiments, the information from the positioning system can be obtained as a combination of information from multiple sources. Illustratively, the positioning system can obtain information from various input sources and determine the positioning information of the vehicle. In other embodiments, the positioning system can also determine motion - related operating parameters such as direction of movement, speed, acceleration, etc.

[0036] In yet another aspect, in some embodiments, one or more navigation systems can provide (or request) an input to identify navigation-related information. Exemplarily, the navigation system can obtain positioning information from a positioning system and identify characteristics or information about the identified location. For example, the navigation system can identify current characteristics of a road, such as an expected lane merge, lane split, turning lane, etc., based on the configured information. The navigation system can also identify a proposed or intended lane location in a multi-lane road based on the direction provided or expected for the vehicle user. As described above, information from the navigation system may be omitted, ignored, or otherwise not utilized.

[0037] In block 304, the vehicle pitch processing component calculates or determines the absolute vehicle pitch as a function of the collected navigation parameters, position parameters, and motion parameters. Exemplarily, the vehicle pitch processing component can implement the absolute pitch calculation subroutine described with respect to FIG. 3C.

[0038] Prior to the description of the exemplary absolute pitch calculation subroutine, a general description of the dynamic calculation of vehicle pitch during a first operating state will be provided. One of ordinary skill in the art will understand that one of various algorithms or methodologies may be implemented to determine the absolute vehicle pitch based on the collected navigation parameters, position parameters, and operating parameters. An example of such a technique is disclosed in U.S. Patent No. 6,714,851, entitled "Method For Road Grade / Vehicle Pitch Estimation," filed on January 7, 2002, which is hereby incorporated by reference in its entirety. Another example of such a technique is disclosed in Henrik Jansson, Ermin Kozica, Karl Henrik Johansson, "A Sensor And Data Fusion Algorithm For Road Grade Estimation," 5th IFAC Symposium on Advances in Automotive Control (2007), which is also hereby incorporated by reference in its entirety. Any number of additional or alternative specific algorithms, generally referred to as fusion algorithms, for estimating road grade can be utilized.

[0039] Referring now to FIG. 3C, an exemplary subroutine 350 for dynamically calculating vehicle pitch based on a first operating state of a vehicle is described. Exemplarily, subroutine 350 corresponds to a fusion algorithm that facilitates determination of vehicle pitch based on altitude information of the vehicle and additional vehicle operating parameters. Exemplarily, subroutine 350 only requires a minimum of two sets of input data to perform vehicle pitch determination and does not require continuous monitoring or processing of vehicle operating data. Before starting subroutine 350, the vehicle pitch processing component can determine whether it can process vehicle motion inputs or obtain the necessary inputs for the vehicle pitch processing component, and whether the load on the vehicle is stable enough to calculate vehicle pitch (e.g., the vehicle load is complete). For example, the vehicle pitch processing component can determine whether a location information sensor is operable and receiving a location information signal (e.g., a GPS signal). In another example, the vehicle pitch processing component can determine whether an accelerometer sensor and a speed sensor are operable and generating signals. In yet another example, the vehicle pitch processing component can determine an indication of vehicle occupancy completion, such as whether all doors are closed, whether safety belts are fastened, whether the vehicle transmission is engaged, etc. In a further example, the vehicle pitch processing component can determine whether there are specific requirements regarding a vehicle operating status that may not be optimized for vehicle pitch determination, including but not limited to vehicle transportation, vehicle service / test, operating the vehicle in reverse, etc. In such an example, the vehicle pitch processing component can determine to delay the implementation of subroutine 350, cancel the implementation of the subroutine, modify the implementation of the subroutine, etc.

[0040] In block 352, the vehicle pitch processing component obtains a location sensor input corresponding to a first measurement of a location. Exemplarily, the location sensor input can correspond to specific altitude information based on the current location of the vehicle. Such altitude information can be included in signals received from a location service component, such as GPS signal information that can be received in the vehicle. The altitude information can be based on one or more different reference points. Additionally, the location service component can provide multiple types / formats of altitude information that can be selected by the vehicle pitch processing component.

[0041] In block 354, the vehicle pitch processing component obtains an operation sensor input corresponding to the same first measured location. Exemplarily, the operation sensor input can include timing information, vehicle speed information, and acceleration measurements. The acceleration measurements may be continuously collected and stored. In some embodiments, the acceleration value (e.g., A) can be further processed to improve accuracy when the sensor measurements are noisy or when the vehicle is actively loaded / moving.

[0042] Assuming the vehicle is not stopped and is continuously moving, in block 356, the vehicle pitch processing component obtains an additional location sensor input corresponding to the selection of at least one additional measurement point. In this regard, the second location and operation inputs can be selected from a set of continuously measured and collected inputs. For example, the second set of inputs can be selected based on exceeding a minimum movement threshold. As described above, the location sensor input can correspond to specific altitude information based on the current location of the vehicle (e.g., the second location). For the purposes of subroutine 350, the vehicle pitch processing component attempts to collect or define the altitude information according to the same common reference point or calculation process utilized in the first sensor information (block 352). This facilitates the comparison between two or more collected values.

[0043] At block 358, the vehicle pitch processing component obtains second motion sensor inputs. Illustratively, the motion sensor inputs may include second timing information, second vehicle speed information, and longitudinal acceleration measurements. As previously mentioned, the longitudinal acceleration measurements may be continuously collected and stored.

[0044] In block 360, a vehicle pitch processing component back-calculates absolute vehicle pitch based on two sets of location sensor and motion sensor information. Illustratively, block 360 corresponds to integrating longitudinal acceleration measurements to estimate a range-averaged global attitude of the longitudinal acceleration measurements. The vehicle pitch processing component can further remove wheel velocity contributions and the effects of changes in average gravity on the slope.

[0045] Equation 1 defines such an exemplary inverse solution as follows:

number

[0046] Exemplarily, the longitudinal acceleration measurement (A x ) may be processed such that any compensation or processing may be removed (e.g., uncompensated). As described above, the two elevation measurements (Elevation2 and Elevation1) may also be processed to have a common reference point or to select a common reference point that may have a minimal amount of error based on the distance between the two measurements. Illustratively, the location during the drive when the first elevation measurement is taken and the enclosure period when the line integral calculation is performed may be delayed or advanced to optimize according to conditions such as GPS elevation accuracy.

[0047] In decision block 362, a test is performed to determine whether to verify the calculated absolute vehicle pitch. Exemplarily, the vehicle pitch processing component can ensure that the determined / calculated vehicle pitch information is not incorrect or otherwise characterized as untrustworthy. In one example, if the vehicle pitch processing component determines that a door has been opened or the vehicle has shifted transmission status (e.g., reverse), the vehicle pitch processing component can consider the vehicle pitch calculation to be untrustworthy. In another example, the vehicle pitch processing component can compare the determined / calculated vehicle pitch with a historical value of the vehicle pitch to determine a confidence factor related to whether the determined vehicle pitch is within an acceptable range of values based on previous determinations / calculations. In yet another example, the vehicle pitch processing component can periodically update the routine by causing a recalculation of the vehicle pitch based on different location service measurements to mitigate potential intermittent outages of the location service signal. In yet another example, the vehicle pitch processing component can utilize inputs from other sensors such as a weight sensor, engine torque, etc. to verify whether the calculated vehicle pitch matches an expected value of the vehicle weight measurement or the torque generated by the vehicle to cause vehicle propulsion. In such an embodiment, the vehicle pitch processing component can utilize a historical vehicle pitch or a default value. The vehicle pitch processing component can utilize a validity monitor in decision block 362 to verify the vehicle pitch. The validity monitor can analyze the input or calculated value to verify the vehicle pitch or reject the determined vehicle pitch. The validity monitor can compare the determined vehicle pitch with a calculated vehicle pitch limit calculated based on the gross vehicle weight rating and known suspension spring constants, and reject the vehicle pitch value if the vehicle pitch value is outside the limit. The validity monitor can reject the vehicle pitch value if the calculated average vehicle speed between GPS sampling points exceeds the maximum possible speed of the vehicle.The validity monitor can reject the vehicle pitch value if the calculated average gradient between GPS sampling points is too steep to be acceptable for the vehicle to climb successfully. The validity monitor can reject the vehicle pitch value if the calculated average motor power between GPS sampling points is too high (exceeding the capacity of the vehicle power train) to be acceptable. The validity monitor can reject the vehicle pitch value if the vehicle pitch value suggests a very nose-down condition, but the independent mass estimate suggests that the vehicle has a very heavy load. The validity monitor can reject the vehicle pitch value if the vehicle pitch value suggests a very nose-up condition, but the independent mass estimate suggests that the vehicle has a very low load. In another embodiment, the vehicle pitch processing component can repeat one or more portions of subroutine 350 for updated calculations. It should be further understood that verifying vehicle pitch can be used to verify other forms of vehicle pitch, such as absolute vehicle pitch or relative vehicle pitch. In block 364, the subroutine ends with a return of the calculated absolute vehicle pitch.

[0048] Returning to FIG. 3A, in block 306, the vehicle pitch processing component stores the determined vehicle pitch as the absolute vehicle pitch. Exemplarily, the control component can utilize the stored vehicle pitch as an input to various processes, such as headlight leveling. However, some control components, such as headlight aiming during the first operating state, may be inactive. Additionally, in some specific embodiments, the vehicle pitch information can be invalidated or otherwise made unavailable during transportation, towing, or certain scenarios. Additionally, as further explained, the stored absolute vehicle pitch information can be utilized to determine the relative vehicle pitch when the vehicle is in the second operating state.

[0049] Exemplarily, in some embodiments, the vehicle need not continuously determine the vehicle pitch when the vehicle is in the first operating state. Thus, the measured value of the vehicle pitch during the first operating state may be valid during a time period when navigation information or position information may be unavailable to the vehicle or otherwise not considered valid (e.g., the GPS signal may be unavailable or unreliable). Additionally, the vehicle pitch processing component may also be configured to periodically calculate the vehicle pitch during intervals or when various criteria are met. This can provide additional efficiency related to power management or power savings.

[0050] In determination block 308, a test is performed to determine whether the vehicle can be characterized as having a stable orientation with respect to the Earth's gravitational field for the purpose of determining the vehicle pitch. Exemplarily, a situation where the vehicle speed is below a vehicle speed threshold can be considered sufficient for such characterization. Exemplarily, the vehicle speed threshold can correspond to the minimum vehicle speed at which determination of the vehicle pitch using navigation information and position information may not be available. Such a vehicle speed can be characterized as when the vehicle is approaching a stop position. If the vehicle speed is not below the threshold, routine 300 returns to "A". Alternatively, if the vehicle speed is less than the threshold, routine 300 proceeds to block 310. In other embodiments, alternative or additional criteria may be considered part of the characterization.

[0051] Starting from block 310, routine 300 will process information resulting from or associated with the dynamic determination of the vehicle pitch during the second operating state (e.g., vehicle speed below the threshold). Exemplarily, the second operating state can be characterized as a state where the vehicle gradient remains the same because the vehicle is not moving and the vehicle pitch can change based on changes in the vehicle's operating parameters, load, passengers, etc. Exemplarily, the vehicle pitch in the second operating state can be determined based on Equation (2).

Number

[0052] In one approach, the RoadGrade information can be provided based on navigation information about the current location. The longitudinal acceleration (A x ) can be provided based on the output from the longitudinal acceleration component of the vehicle. The longitudinal acceleration can be further processed to remove the contribution of the vehicle wheels as explained by the input wheel speed data. The gravitational acceleration (g) may be predefined. In another approach, two instances of this equation are compared while the vehicle is stationary on the same road surface, providing the ability to calculate the difference in vehicle pitch over two measurements of A x without the need to solve for the RoadGrade information. In block 310, the vehicle pitch processing component obtains a second vehicle motion input (e.g., for the first motion input obtained in block 302). As described above, in an exemplary embodiment, the vehicle pitch processing component can process the input from the vehicle motion component, i.e., the acceleration sensor. In block 312, the vehicle pitch processing component stores the second motion information and associates the stored motion input with the previously calculated and stored absolute vehicle pitch information.

[0053] In decision block 314, the vehicle pitch processing component determines whether the vehicle can be characterized as remaining in the second operating state. Exemplarily, the determination and characterization can be based on various operating parameters such as identifying passenger entry or exit, identifying the operation of a storage area (e.g., trunk space or storage compartment), monitoring the transmission status of the vehicle (parked vs. drive or reverse), identifying the activation of a navigation component, identifying the activation of different power modes, detecting the release of a charging system, etc. In decision block 314, the vehicle pitch processing component can determine whether the vehicle can be characterized as likely to transition from the second operating state to the first operating state. This can be determined based on the operating parameters described above. For example, the vehicle can be characterized as likely to transition from the second operating status to the first operating state when all vehicle doors, trunk, or lid are closed. Block 314 loops back to block 310 as long as the vehicle remains in the second operating state.

[0054] Referring to FIG. 3B, in decision block 316, the vehicle pitch processing component determines that the vehicle can no longer be characterized as remaining in the second operating state and is likely to transition to the first operating state, and the vehicle pitch processing component obtains additional vehicle motion inputs (e.g., acceleration measurements) for the first motion input obtained at block 302 and the second motion input obtained at block 310. Exemplarily, the specific triggers for which additional vehicle motion inputs are collected can be changed, such as speed thresholds, changes in transmission status, door / release latch status, etc. In decision block 316, the vehicle pitch processing component obtains a third set of inputs (which can be motion inputs) corresponding to a third operating state. It should be understood that the third operating state can correspond to the determination that the vehicle can no longer be characterized as remaining in the second operating state and is likely to transition to the first operating state. In block 318, the vehicle pitch processing component stores the third motion information.

[0055] In block 320, the vehicle pitch processing component determines the relative change in vehicle pitch by utilizing the changes in the second and third motion inputs. In this manner, since the vehicle is in the second operating state, the RoadGrade variable in Equation (1) remains constant in the virtual pitch calculation that includes the second and third motion parameters. Thus, the comparison of the changes in the readings from the longitudinal acceleration sensor can be attributed to the change in vehicle pitch when the vehicle is not operating otherwise. In block 322, the vehicle pitch processing component associates the determined change in motion information with the previously stored absolute vehicle pitch and stores that value as vehicle pitch information for use by the control component and the like. In block 324, the vehicle pitch processing component stores the relative vehicle pitch. Routine 300 returns to decision block 308.

[0056] Next, referring to FIG. 4, routine 400 for utilizing vehicle pitch information will be described. As described above, the vehicle pitch processing component can provide the determined vehicle pitch information to the control component for operation. In block 402, the vehicle pitch processing component provides or makes available the vehicle pitch information. Exemplarily, the vehicle pitch information can correspond to either the absolute vehicle pitch information determined in routine 300 or the relative vehicle pitch information determined in routine 300, based on the operating state of the vehicle.

[0057] In decision block 404, a test is performed to determine whether to further process, manage, or prevent the use of the vehicle pitch information. As described above, in some particular embodiments, during transportation, towing, or in certain scenarios, etc., the vehicle pitch information vehicle pitch processing component may be disabled or otherwise made unavailable. If the vehicle pitch information is to be further processed, managed, or otherwise prevented, in block 406, the vehicle pitch processing component can delete the vehicle pitch information or mark it as unavailable. In other embodiments, the vehicle pitch processing component can use default or historical information. Alternatively, in block 408, the control component can utilize the vehicle pitch information as described herein. As described above, in one embodiment, the control component can include a control component for a headlight leveling function that is at least partially based on the output from the vehicle pitch processing component. In another embodiment, the control component can include a control component for a headlight aiming function that is at least partially based on the output from the vehicle pitch processing component. Other embodiments of the control component can include, but are not limited to, a suspension control component, a collision avoidance component, etc. Routine operation 400 returns to block 402.

[0058] The foregoing disclosure is not intended to limit the present disclosure to the exact forms disclosed or to a particular field of use. Accordingly, various alternative embodiments and / or modifications to the present disclosure are contemplated as being possible whether explicitly described or implied herein in light of the present disclosure. Although embodiments of the present disclosure have been described in this manner, those skilled in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure. Accordingly, the present disclosure is limited only by the claims.

[0059] In the foregoing specification, the present disclosure has been described with reference to specific embodiments. However, as will be understood by those skilled in the art, the various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the present disclosure. Accordingly, this description should be regarded as illustrative and is for the purpose of teaching those skilled in the art how to make and use various embodiments of the disclosed decision and control algorithms. It should be understood that the forms of the disclosure shown and described herein are to be construed as representative embodiments. Equivalent elements, materials, processes, or steps may be substituted for those typically illustrated and described herein. Further, certain features of the present disclosure may be utilized independently of the use of other features, as will become apparent to those skilled in the art after having obtained the benefit of this description of the present disclosure. Expressions such as "including", "comprising", "incorporating", "consisting of", "having", "is", etc., used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, i.e., to allow for the presence of items, components, or elements not explicitly recited. References to the singular are also to be construed as relating to the plural.

[0060] Furthermore, the various embodiments disclosed herein should be construed in an exemplary and illustrative sense and should in no way be construed as limiting the present disclosure. All references to couplings (e.g., attached, fixed, coupled, connected, etc.) are used only to assist the reader in understanding the present disclosure and do not, in particular, impose limitations with respect to the position, orientation, or use of the systems and / or methods disclosed herein. Accordingly, references to couplings should, if at all, be construed broadly. Further, such references to couplings do not necessarily imply that the two elements are directly connected to each other.

[0061] Additionally, without limitation, all numerical terms such as "first", "second", "third", "primary", "secondary", "main", or any other ordinary and / or numerical terms should also be interpreted only as identifiers to assist the reader's understanding of the various elements, embodiments, variations, and / or modifications of the present disclosure, and in particular, should not create any limitation with respect to the order or priority of any element, embodiment, variation, and / or modification with respect to, or beyond, another element, embodiment, variation, and / or modification.

[0062] It will also be understood that one or more of the elements shown in the drawings / figures may also be implemented in a more separated or integrated manner, or in some cases removed or rendered inoperative, as may be useful according to a particular application.

Claims

1. A method for determining vehicle pitch for a plurality of vehicle operating states, obtaining a first set of inputs corresponding to a first operating state of the vehicle, the first set of inputs corresponding to first operating information including position information, longitudinal acceleration sensor information, and at least one additional vehicle operating parameter; calculating an absolute vehicle pitch based on the first operating information, the calculating of the absolute vehicle pitch being based on at least two distinct position measurements; storing the absolute vehicle pitch; determining that the vehicle has transitioned to a second operating state; obtaining a second set of inputs corresponding to the second operating state of the vehicle, the second set of inputs corresponding to second operating information including longitudinal acceleration sensor information; determining that the vehicle is characterized as likely to transition from the second operating state to the first operating state; obtaining a third set of inputs corresponding to a third operating state of the vehicle, the third set of inputs corresponding to third operating information including updated longitudinal acceleration sensor information; determining a relative vehicle pitch change based on processing the second operating information and the third operating information; storing the relative vehicle pitch change together with the absolute vehicle pitch; A method comprising.

2. The method of claim 1, further comprising causing control of a vehicle component based on the relative vehicle pitch change or the absolute vehicle pitch.

3. The method of claim 2, wherein the vehicle component includes a headlight leveling component configured to level the headlights based on the relative vehicle pitch change or the absolute vehicle pitch.

4. The method of claim 1, wherein the at least one additional vehicle operating parameter includes vehicle speed information.

5. The method of claim 1, wherein the determining that the vehicle is characterized as likely to transition from the second operating state to the first operating state includes determining that all vehicle doors are closed.

6. The method of claim 1, wherein the position information includes altitude information.

7. The step of determining that the vehicle has transitioned to the second operating state includes analyzing a vehicle door status, a parking brake status, a transmission status, an ignition status, or a vehicle speed, the method according to claim 1.

8. A method for determining a vehicle pitch of a vehicle, comprising: obtaining a first location sensor input corresponding to a first measurement of a location; obtaining a first motion sensor input corresponding to the first measurement of the location; obtaining a second location sensor input corresponding to a second measurement of a location; obtaining a second motion sensor input corresponding to the second measurement of the location; determining a vehicle pitch based at least in part on the first location sensor input, the second location sensor input, the first motion sensor input, and the second motion sensor input; A method comprising:

9. The method according to claim 8, further comprising the step of verifying the vehicle pitch.

10. The method according to claim 8, wherein the method includes continuously obtaining a location sensor input or a motion sensor input.

11. The method according to claim 8, wherein the first location sensor input and the second location sensor input correspond to specific altitude information.

12. The method according to claim 8, wherein the first motion sensor input and the second motion location sensor input correspond to timing information, vehicle speed information, and acceleration measurements.

13. The method according to claim 8, further comprising the step of actuating a vehicle component based on the vehicle pitch.

14. The method according to claim 13, wherein the vehicle component includes a headlight leveling component configured to level a headlight based on the vehicle pitch.

15. The method according to claim 8, further comprising the step of facilitating aiming of the headlight at the vehicle pitch.

16. A system for determining a vehicle pitch of a vehicle, comprising: a GPS signal receiver; an accelerometer; a speed sensor; a processing component, wherein the processing component: receives a first altitude input corresponding to a first measurement of a location from the GPS signal receiver; Receiving a first motion sensor input corresponding to the first location measurement value from the accelerometer and the speed sensor; Receiving a second altitude sensor input corresponding to a second measurement value of the location from the GPS signal receiver; Receiving a second motion sensor input corresponding to the second location measurement value from the accelerometer and the speed sensor; Determining the vehicle pitch based at least in part on the first altitude input, the second altitude input, the first motion sensor input, and the second motion sensor input. A system configured to perform.

17. The system according to claim 16, further comprising a vehicle control component, wherein the vehicle control component is controlled at least in part based on the vehicle pitch.

18. The system according to claim 17, wherein the vehicle control component includes a headlight leveling component configured to level the headlights based on the vehicle pitch.

19. The system according to claim 17, wherein the vehicle control component includes a suspension component.

20. A door status sensor configured to generate a door status; A parking brake sensor configured to generate a parking brake status; An ignition state sensor configured to generate an ignition state status, and the system is configured to determine an operating state of the vehicle based on the door status, the parking brake status, or the ignition state sensor. The system according to claim 16.

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