Systems and methods for determining pedal actuation states

Abstract

A method for determining the state of a pedal actuation system in a vehicle (10), the method comprising: Receiving a position sensor signal (232) by a position sensor assembly (206), the position sensor signal (232) indicating a position of an actuation pedal (203) within the pedal actuation system, the position sensor assembly (206) comprising an optical camera component positioned beneath a front instrument panel of the vehicle (10) to determine the position of the actuation pedal (203); Receiving a force sensor signal (231) indicating a pressure force exerted on the actuating pedal (203); and Determining, with a processor (44), a state of the actuation pedal (203) based on the position sensor signal (232) and the force sensor signal (231), wherein the state of the actuation pedal (203) is one of a normal operating state and a fault state.

Description

TECHNICAL FIELDThe present disclosure relates generally to vehicles, and more particularly to systems for determining the state of various pedals (such as brake, accelerator, and clutch pedals) used to control these vehicles.BACKGROUNDModern vehicles typically have a variety of sensors and controllers, many of which (e.g., brake pedal actuators and accelerator pedal actuators) may be implemented as "fly-by-wire" electronic systems, rather than as mechanically controlled systems. These electronic implementations avoid the bulky and costly hydraulic system components used in conventional vehicles, but since they do not provide direct feedback between the actuator input and actuator response, these arrangements are preferably continuously monitored by the controller to ensure proper operation and detect fault conditions. While these systems are very effective and safe, there remains a need for systems that provide more confidence in the state of the foot pedal systems used for vehicle control.Accordingly, it is desirable to provide improved systems and methods capable of detecting the state of the pedal actuators used in vehicles and other movable platforms with a high degree of safety. Further, other desirable features and features of the present invention will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings, and the foregoing technical field and background.DE 10 2012 221 610 A1 describes a system for detecting an accelerator pedal failure in an accelerator pedal system which contains a vehicle control system, the pedal failure detection system having: an accelerator pedal; a pedal arm; a sensor which is configured to interpret a force applied to the accelerator pedal and is further configured to transmit a signal as a sensor output to the vehicle control system, the vehicle control system being configured to correlate the sensor output with an accelerator pedal position and to indicate a failure condition if the sensor output cannot be read in view of the accelerator pedal position.DE 10 2007 060 217 A1 describes a device for detecting a malfunction of an accelerator pedal for a motor vehicle, comprising: an accelerator pedal lever which can be actuated by the driver and an evaluation device for detecting a malfunction of the accelerator pedal lever as a function of the deflection of the accelerator pedal lever and the force exerted by the driver on the accelerator pedal lever.US 2011 / 0 271 736 A1 describes a system for determining a setpoint value which is connected to a position of a pedal in a motor vehicle, wherein the system comprises two sensors which each measure a value connected to the pedal position. The system includes a mechanism capable of switching between first and second states at a predetermined shift position of the pedal, and a mechanism that generates the target value based on the measurement values of the two sensors and a current state of the shift mechanism. The generating mechanism is capable of selecting the amount corresponding to the smallest of the pedal positions when the shift mechanism is in the first state and selecting the amount corresponding to the largest of the pedal positions when the shift mechanism is in the second state. DE 195 10 525 A1 describes a method and a device for controlling or regulating the brake system of a vehicle, in which the brake pedal actuation is detected by at least two measuring devices and the braking request of the driver is determined from the measurement signals. For fault detection, the braking request is determined from the at least two actuation signals independently of one another and further processed. For fault localization, a third measuring device is provided that detects the brake pedal actuation. The control unit carrying out the brake control consists of at least two microcomputers, both of which are supplied with the signals of the at least two measuring devices, while the signal of the monitoring measuring device is supplied with only one microcomputer.SUMMARYSystems and methods for controlling a vehicle are provided. According to the invention, a method for determining the state of a pedal actuation system within a vehicle includes receiving, by a position sensor assembly, a position sensor signal, the position sensor signal indicative of a position of an actuation pedal within the pedal actuation system, the position sensor assembly comprising an optical camera component positioned below a front dashboard of the vehicle to determine the position of the actuation pedal, receiving, by a processor, a force sensor signal indicative of a compressive force applied to the actuation pedal, and determining, based on the position sensor signal and the force sensor signal, a state of the actuation pedal. The state of the operation pedal is a normal operation state and a failure state.In one embodiment, the actuation pedal is a brake pedal. In another embodiment, the actuation pedal is an accelerator pedal.In one embodiment, the method further includes performing a remedial action when the state of the actuation pedal is a fault condition.In one embodiment, the remedial action includes at least one of reporting the fault condition, a change in braking of the vehicle, and a change in acceleration of the vehicle.In one embodiment, determining the state of the actuation pedal includes determining that the actuation pedal is in the fault state when the force sensor signal indicates a non-zero force while the position sensor signal indicates that the actuation pedal has not moved beyond a sleep state.In one embodiment, determining the state of the actuation pedal includes determining that the actuation pedal is in the fault state when the force sensor signal indicates a zero force, while the position sensor signal indicates that the actuation pedal has not moved beyond a sleep state.In one embodiment, the method includes performing a diagnostic test of the position sensor assembly and the force sensor assembly prior to determining the state of the actuation pedal.According to the invention, a pedal state determination system for a vehicle includes a pedal operation system and a pedal state determination module. The pedal actuation system includes an actuation pedal, a force sensor assembly for generating a force sensor signal indicative of a force applied to the actuation pedal, and a position sensor assembly for generating a position sensor signal indicative of the position of the actuation pedal, the position sensor assembly comprising an optical camera component positioned under a front dashboard of the vehicle to determine the position of the actuation pedal. The pedal state determination module including a processor is configured to determine a state of the operation pedal based on the position sensor signal and the force sensor signal, wherein the state of the operation pedal is one of a normal operation state and a failure state.In one embodiment, the actuation pedal is a brake pedal. In one embodiment, the actuation pedal is an accelerator pedal.In one embodiment, the pedal state determination module performs a remedial action when the state of the actuation pedal is a fault condition.In one embodiment, the remedial action includes at least one of reporting the fault condition, a change in braking of the vehicle, and a change in acceleration of the vehicle.In one embodiment, the pedal state determination module determines that the actuation pedal is in the fault state when the force sensor signal indicates a non-zero force, while the position sensor signal indicates that the actuation pedal has not moved beyond a sleep state.In one embodiment, the pedal state determination module determines that the actuation pedal is in the fault state when the force sensor signal indicates a zero force, while the position sensor signal indicates that the actuation pedal has moved beyond a sleep state.In one embodiment, the pedal state determination module performs a diagnostic test of the position sensor assembly and the force sensor assembly prior to determining the state of the actuation pedal.A vehicle according to an embodiment includes: a pedal actuation system having an actuation pedal, a force sensor assembly configured to generate a force sensor signal indicative of a force applied to the actuation pedal, and a position sensor assembly configured to generate a position sensor signal indicative of the position of the actuation pedal; and a pedal state determination module including a processor configured to determine a state of the actuation pedal based on the position sensor signal and the force sensor signal, wherein the state of the actuation pedal is one of a normal operating state and a fault state.In one embodiment, the actuation pedal is a brake pedal.In one embodiment, the pedal state determination module determines that the actuation pedal is in the fault state when the force sensor signal indicates a non-zero force, while the position sensor signal indicates that the actuation pedal has not moved beyond a sleep state.In one embodiment, the pedal state determination module determines that the actuation pedal is in the fault state when the force sensor signal indicates a zero force, while the position sensor signal indicates that the actuation pedal has moved beyond a sleep state.DESCRIPTION OF THE DRAWINGSThe exemplary embodiments will be described below in connection with the following drawings, wherein like reference numerals designate like elements, and wherein: FIG. 1 is a functional block diagram illustrating an example vehicle including a system for detecting a condition of a restraint system according to various embodiments; FIG. 2 illustrates a pedal actuation system according to an embodiment; FIGS. 3-5 illustrate exemplary pedal actuation systems according to various embodiments; FIG. 6 is a dataflow diagram illustrating a system according to various embodiments; and FIG. 7 is a flowchart illustrating a control method for controlling a vehicle according to various embodiments.DETAILED DESCRIPTIONSystems and methods for determining the state of a pedal actuator (e.g., a brake pedal or an accelerator pedal) are described that use both a force sensor and a position sensor coupled to the pedal actuator. By comparing the signals received from the force and position sensors and judging whether these signals are consistent, the system can determine with high certainty whether the pedal actuator is in a normal operating state or in a fault state. For example, the system may determine that a fault has occurred (e.g., clamps the pedal) when the force sensor detects that no force is being applied to the pedal, but the pedal is displaced from its rest position by a non-zero amount. Likewise, the system may detect a fault condition when the pedal is being applied with force but the pedal has not been moved beyond its rest position.The following detailed description is merely illustrative in nature and is not intended to limit the application and use in any way. Furthermore, there is no intention in the preceding technical field, background, summary or the following detailed description to be bound by any expressly or implicitly presented theory. As used herein, the term "module" refers to any hardware, software, firmware products, electronic control components, processing logic, and / or processor devices, alone or in any combination including, but not limited to, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), an electronic circuit, a processor (shared, dedicated, or group processor), and memory that executes one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the described functionality.Implementations of the present disclosure may be described herein as functional and / or logical block components and various processing steps. It should be appreciated that such block components may be constructed from any number of hardware, software, and / or firmware components configured to perform the required functions. For example, an embodiment of the present disclosure of a system or component may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, look-up tables, or the like, that may perform multiple functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will appreciate that the exemplary embodiments of the present disclosure may be used in conjunction with any number of systems, and that the system described herein is merely an exemplary embodiment of the present disclosure.For brevity, conventional techniques associated with RF sensing, vehicle restraint systems, signal processing, data transmission, signaling, control, machine learning, image analysis, and other functional aspects of the systems (and the individual operating components of the systems) may not be described in detail herein. Furthermore, the connection lines shown in the various figures are intended to represent exemplary functional relationships and / or physical connections between the various elements. It should be appreciated that many alternative or additional functional relationships or physical connections may be present in an embodiment of the present disclosure.Referring to FIG. 1, a vehicle 10 employing a system according to various embodiments generally includes a chassis 12, a body 14, front wheels 16, and rear wheels 18. the body 14 is disposed on the chassis 12 and substantially envelopes the other components of the vehicle 10. The wheels 16-18 are each rotatably connected to the chassis 12 near a respective corner of the body 14.In various embodiments, vehicle 10 is characterized by a degree of autonomy. For example, vehicle 10 may correspond to a level four or level five automated driving level automation system of the society of Automotive Engineers (SAE) "J3016", according to the standard taxonomy of automated driving levels. With this terminology, a level four system refers to "high automation" with reference to a driving mode in which the automated driving system takes all aspects of the dynamic driving task, even if a human driver does not respond appropriately to a request to intervene. A level five system, on the other hand, shows "full automation" and denotes a driving mode in which the automated driving system satisfies all aspects of the dynamic driving task under all roadway and environmental conditions that a human driver can handle. It should be understood that the embodiments according to the present subject matter are not limited to a particular taxonomy or rubric of the automation categories. Moreover, road construction recognition systems according to the present embodiment can be used in connection with any vehicle using a navigation system for route guidance. Further, the vehicle 10 may be a traditional non-vehicle.While the vehicle 10 is shown as a passenger car in the illustrated embodiment, it should be appreciated that any type of vehicle including motor bicycles, trucks, sport utility vehicles, watercraft, aircraft, and other movable platforms that utilize a restraint system may also utilize the various methods and systems described herein.Referring again to FIG. 1, the vehicle 10 generally includes a propulsion system 20, a transmission system 22, a steering system 24, a braking system 26, one or more pedal actuator assemblies 27, a sensor system 28, an actuator system 30, at least one data store 32, at least one controller 34, and a communication system 36 for communicating with an external system 48. The propulsion system 20 may include an internal combustion engine, an electric machine such as a traction motor and / or a fuel cell propulsion system, in various embodiments. The transmission system 22 is configured to transmit power from the propulsion system 20 to the vehicle wheels 16 and 18 according to the selectable gear ratios. According to various embodiments, the transmission system 22 may include a step ratio automatic transmission, a continuously variable transmission, or another suitable transmission.The brake system 26 is configured to provide a braking torque to the vehicle wheels 16 and 18. The brake system 26 may include friction brakes, brake-by-wire, a regenerative brake system such as an electric machine, and / or other suitable brake systems, in various embodiments. The brake system 26 may be actuated via one of the pedal actuation systems 27.The steering system 24 affects a position of the vehicle wheels 16 and / or 18. While in some embodiments, within the scope of the present disclosure, shown as a steering wheel 25 for purposes of illustration, the steering system 24 may not include a steering wheel.The sensor system 28 includes one or more sensor devices 40 a- 40 nthat sense observable conditions of the exterior environment and / or the interior environment of the vehicle 10. Sensing devices 40 a- 40 nmay include, but are not limited to, radars, lidars, global positioning systems, optical cameras, thermal cameras, ultrasonic sensors, force sensors, and position sensors (e.g., in conjunction with pedal actuator assemblies 27), and / or other sensors.The actuator system 30 includes one or more actuator devices 42 a- 42 nthat control one or more vehicle characteristics, such as, but not limited to, the propulsion system 20, the transmission system 22, the steering system 24, and the brake system 26. In various embodiments, the vehicle 10 may also include vehicle interior and / or exterior equipment not shown in FIG. 1, such as various doors, trunk and cabin equipment such as air, music, lighting, touch screen display components (as used in connection with navigation systems), and the like. One or more of the actuator devices 42 a- 42 nmay be controlled via pedal actuator assemblies 27, which may include, for example, a brake pedal, an accelerator pedal, a clutch pedal, and the like.The data storage device 32 stores data for use in automatically controlling the vehicle 10. In various embodiments, the defined maps may be predefined and retrieved from a remote system. For example, the defined maps may be assembled by the remote system and communicated (wirelessly and / or wired) to the vehicle 10 and stored in the data storage device 32. Route information may also be stored in the data device 32, i.e., in a series of road segments (geographically associated with one or more of the defined maps) that together define a route that the user may travel from a starting location (e.g., the user's current location) to a destination location. As can be seen, the data storage device 32 may be a portion of the controller 34 separate from the controller 34, or a portion of the controller 34 and part of a separate system.The controller 34 includes at least one processor 44 and a computer readable storage device or media 46. the processor 44 may be a special purpose or commercially available processor, a central processing unit (CPU), a graphics processing unit (GPU) among multiple processors coupled to the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chip set), a combination thereof, or generally any device for executing instructions. The computer readable storage device or media 46 may include volatile and non-volatile memory in read only memory (ROM), random access memory (RAM), and keep alive memory (KAM). KAM is a persistent or non-volatile memory that can be used to store various operating variables while the processor 44 is off. The computer readable storage device or media 46 may be implemented using any of a number of known storage devices, such as PROMs (programmable read-only memory), EPROMs (electric PROM), EEPROMs (electrically erasable PROM), flash memory, or any other electric, magnetic, optical, or combined storage devices that can store data, some of which represent executable instructions, used by the controller 34 in controlling the vehicle 10.The instructions may include one or more separate programs, each of which comprises an ordered listing of executable instructions for implementing logical functions. The instructions, when executed by the processor 44, receive and process signals from the sensor system 28, perform logic, computations, methods, and / or algorithms for automatically controlling the components of the vehicle 10, and generate control signals that are transmitted to the actuator system 30 to automatically control the components of the vehicle 10 based on the logic, computations, methods, and / or algorithms. Although only one controller 34 is shown in FIG. 1, embodiments of the vehicle 10 may include any number of controllers 34 that communicate and cooperate via a suitable communication medium or combination of communication media to process the sensor signals, perform logics, calculations, methods, and / or algorithms, and generate control signals to automatically control the functions of the autonomous vehicle 10. In one embodiment, as detailed below, the controller 34 is configured to determine the state of one or more pedal actuator devices (e.g., brake and / or accelerator pedals) provided in the vehicle 10.The communication system 36 is configured to wirelessly communicate information to and from other entities 48, such as, but not limited to, other vehicles ("V2V" communication), infrastructure ("V2I" communication), remote transportation systems, and / or user devices. In an exemplary embodiment, the wireless communication system 36 is configured to communicate over a wireless local area network (WLAN) using the IEEE 802.11 standard, over Bluetooth, or via mobile data communication. However, additional or alternative communication methods, such as a dedicated short-range communication (DSRC) channel, are also contemplated within the scope of the present disclosure. DSRC channels refer to one-way or two-way short-range to medium-class radio communication channels that have been specifically developed for automotive construction and a corresponding set of protocols and standards.As can be seen, the subject matter disclosed herein provides certain improved characteristics and functions for what can be considered a standard or base vehicle 10. To this end, a vehicle and a vehicle-based transportation system may be modified, augmented, or otherwise augmented to provide the additional functions described in more detail below.As mentioned above, systems and methods for determining the state of one or more pedal actuator assemblies are described. In other words, the present subject matter is directed to determining whether a pedal is in a normal operating state or in a fault state, such as in a "stuck pedal" mode, as will be explained in more detail below.Referring now to FIG. 2, a pedal actuator assembly (or simply "assembly") 200 is illustrated, operated by an occupant with a foot 210, in accordance with various embodiments. In particular, the pedal actuator assembly 200 includes an actuator 203 connected to a contact plate 201 (i.e., a component intended to be directly contacted to the foot 210) via a force sensor assembly 202 that generates a force sensor signal 231 indicative of the magnitude of the compressive force applied to the contact plate 201.The actuation pedal 203 is rigidly coupled to a central shaft component 205, which is displaced along an axis 230 (parallel to the "z" axis) by a compressive force exerted by the foot 210 on the contact plate 201. A spring component 204 is coupled between the actuation pedal 203 and an actuator mounting structure 208 to generate a force that, in the absence of a compressive force from the foot 210 and in the normal operating condition, retracts the actuation pedal 203 to its uppermost or "rest" position. A position sensor assembly 206 is provided to determine the position of the shaft 205 (and thus the actuation pedal 203) with respect to the mounting structure 208 and generate a position sensor signal 232 indicative thereof.The pedal actuator assembly 200 corresponds to any type of pedal actuator presently known or later developed, including, without limitation, a brake pedal actuator, an accelerator pedal actuator, a clutch pedal actuator, or the like. In this regard, it should be appreciated that FIG. 2 illustrates a simplified version of a pedal actuator assembly, which in typical embodiments may also include a number of other components, such as stops, pads, gears, linkages, support members, bushings, and the like. Moreover, the present embodiments are not limited to the geometry illustrated in FIG. 2. For example, the spring component 204 may be configured as a torsion spring and not as a linear spring component as illustrated. Although position sensor assembly 206 is depicted as measuring linear motion of actuation pedal 203 (indirectly through shaft 205), position sensor assembly 206 may instead measure rotational motion of a structure (not illustrated) coupled to actuation pedal 203. Although the applied force, force sensor assembly 202, and position sensor assembly are shown as being substantially coaxial, the invention is not so limited.The position sensor assembly 206 includes any component or combination of components configured to generate a position sensor signal 232 indicative of the position of the actuation pedal 203. The position sensor signal 232 may be analog or digital, absolute, or relative. Various devices can be used for this purpose, such as length measuring devices, rotary encoders, capacitive pick-ups, eddy current sensors, Hall effect sensors, photodiode arrays, proximity sensors, string potentiometers or the like. According to the invention, the position sensor assembly 206 includes an optical camera component (part of the sensor system 28 of FIG. 1 ) positioned below the front dashboard of the vehicle 10 to determine the position of the actuation pedal 203.Force sensor assembly 202 includes any component or combination of components configured to generate a force sensor signal 231 indicative of the force applied to the actuation pedal 206 (e.g., via the contact plate 201). For this purpose, different force sensor devices (also referred to as load cells or pressure sensors) can be used, e.g. piezoelectric load cells, hydraulic load cells, pneumatic load cells, capacitive force sensors, electromagnetic force sensors, fiber-optic force sensors, potentiometric force sensors and the like.For clarity, it is often noted herein that a force is "applied" to the actuation pedal 203, even if that force is not applied directly to the foot 210. For example, in the embodiment shown in FIG. 2, any force applied by the foot 210 is necessarily transmitted via the contact plate 201 and the force sensor assembly 202. That is, the indication that a force is applied to the actuation pedal 203 may be equivalent to the indication that the actuation pedal 203 experiences a force acting directly on another component mechanically coupled to the actuation pedal 203.Force sensor assembly 202 is shown in FIG. 2 as a general functional block, but may include a variety of accessory components in many implementations. FIGS. 3-5 illustrate only three exemplary embodiments. In FIG. 3, for example, the contact plate 201 is pivotable about a hinge component 305 at the "heel end" of the actuating pedal 203 (on the right in this figure). This embodiment also includes a stroke limiter 310 and a return spring 320 in close proximity to the "edge end" of the actuator 203 (left-hand side in this figure) and a centrally located force sensor 302. FIG. 4 illustrates an embodiment that is an inverse version of the embodiment illustrated in FIG. 3. That is, a hinge 305 is provided at the edge end of the operation pedal 203, while the stroke limiter 310 and the return spring 230 are provided at the heel end. FIG. 5 illustrates an embodiment in which two return springs 320 and 321 and two stroke restrictors 310 are provided at opposite ends of the operation pedal 203. These embodiments are not to be considered limiting; for example, contact plate 201 may or may not experience a rotational or a translatory movement during operation. That is, in cases where the force sensor is a solid-state load cell or the like (a type having negligible compression deformation), the use of the springs 320, 321 and the stroke restrictors 310 is not required.FIG. 6 is a dataflow diagram generally illustrating operation of a pedal state determination module (or simply "module") 620 that may be implemented by the controller 34 of FIG. 1. In this regard, it should be appreciated that various embodiments of the system according to the present disclosure may include any number of sub-modules integrated into the controller 34. As can be appreciated, the sub-modules shown in FIG. 4 may be combined and / or further partitioned to operate similarly. Inputs to the module 420 may be received from the sensor system 28 received from other control modules (not shown) associated with the vehicle 10 received from the communication system 36 and / or from other sub-modules (not shown) determined / modeled within the controller 34 of FIG. 1.Referring now to FIG. 6, as well as FIGS. 1 and 2, the module 620 is configured to receive the force sensor signal 231 (from the force sensor assembly 202 of FIG. 2 ) and the position sensor signal 232 (from the position sensor assembly 206 of FIG. 2 ) and generate an output 630 indicative of the state of the pedal actuator assembly 200. The module 620 may be implemented in various ways, for example, by a machine learning model that has undergone supervised or unsupervised learning, or by a relatively simple decision tree based on the values of the force sensor signal 231 and the position sensor signal 232.The output 630 may be a value corresponding to a list of pedal states enumerated. For example, in one embodiment, output 630 is selected from two possible states: (1) "normal operating state" and (2) "fault state.". In further embodiments, the fault condition includes a plurality of possible conditions, each related to a different fault type.In particular, a fault condition, with reference to FIG. 2, may correspond to the fault condition when force sensor signal 231 indicates a non-zero force (i.e., the operator presses foot 210 onto contact plate 201), while position sensor signal 232 indicates that actuation pedal 203 has not been moved beyond its rest state. This failure mode corresponds to a scenario in which the operator cannot operate the operation pedal 203 (i.e., is stuck in the rest position).Another fault condition may correspond to the case where force sensor signal 231 indicates a non-zero force (i.e., the operator presses foot 210 onto contact plate 201), while position sensor signal 232 indicates that actuation pedal 203 has been moved beyond the rest condition. This failure mode corresponds to a scenario in which the drive pedal 203 is stuck in a locked position when the operator does not actually apply pressure to the contact plate 201.In general, the normal operating state may be characterized as the case where the force sensor signal 231 matches the position sensor signal 232 (according to any criteria). For example, it would generally be the case that the position sensor signal 232 indicates a non-zero value when the force sensor signal 231 indicates a non-zero value (and the relationship between these values may be known a priori). Conversely, it would also be the case that the position sensor signal 232 indicates a zero value (or a known idle state value) if the force sensor signal 231 indicates a zero value.Referring now to FIG. 7 and with continued reference to FIGS. 1-4, a flowchart illustrates a control method 700 that may be executed by the module 620 of FIG. 6 will now be described. As can be appreciated in light of the disclosure, the sequence of operations within the methods is not limited to sequential execution as illustrated, but may be performed in one or more varying applicable orders in accordance with the present disclosure. In various embodiments, the method 700 may be performed based on one or more predefined events and / or continuously during operation of the vehicle 10.First, at 701, the system receives the position sensor signal 232 and the force sensor signal 231 from the pedal actuator assembly 200. The nature of these signals has been described in detail above.Subsequently, at 702, it is queried whether the position sensor signal 232 and the force sensor signal 231 indicate a fault state (output 630 of FIG. 6 ). If not, processing returns to 701 and position sensor signal 232 and force sensor signal 231 are further monitored. The determination of an error condition at 702 may be made in various ways as described above. For example, in one embodiment, the system classifies each state as a fault condition in which the force sensor signal is "inconsistent" with the position sensor signal. In a particular embodiment, the system searches for cases where (1) force signal 231 is non-zero while position signal 232 is zero; or (2) force signal 231 is zero and position signal 232 is non-zero. These cases generally correspond to the so-called "stuck pedal" failure modes.Finally, at 703, the system performs remedial action based on the fault condition and type of the pedal actuator assembly 200. These remedial actions may take various forms and take into account various subsystems shown in FIG. 1 (e.g., the brake system 62).When the pedal actuator assembly 200 is a brake pedal assembly, the remedial action may include one or more of notifying the user of a fault (e.g., using a dashboard message, an audible alarm, or the like), limiting the speed of the vehicle 10, and activating an appropriate brake control.When the pedal actuator assembly 200 is an accelerator pedal assembly, the remedial action may include one or more of notifying the user of a fault (e.g., using a dashboard message, an audible alarm, or the like), limiting speed, simply stopping the vehicle 10, and activating appropriate acceleration control.In some embodiments, prior to steps 701 and 702, the system performs a diagnostic test of both the position sensor signal generating circuit 232 and the force sensor signal generating circuit 231, thereby providing additional certainty that a fault condition actually occurs.While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be understood that there are a large number of variations. It is further understood that the exemplary embodiment or exemplary embodiments are merely examples and are not intended to limit the scope, applicability, or configuration of this disclosure in any way. Rather, the foregoing detailed description provides those skilled in the art with a convenient road map for implementing the exemplary embodiment or embodiments. It should be understood that various changes may be made in the function and arrangement of elements without departing from the scope of the disclosure as set forth in the appended claims and their legal equivalents.

Claims

A method for determining the state of a pedal actuation system in a vehicle (10), the method comprising: receiving, by a position sensor assembly (206), a position sensor signal (232), the position sensor signal (232) indicative of a position of an actuation pedal (203) within the pedal actuation system, the position sensor assembly (206) comprising an optical camera component positioned below a front dashboard of the vehicle (10) to determine the position of the actuation pedal (203); receiving a force sensor signal (231) indicative of a compressive force applied to the actuation pedal (203); and determining, with a processor (44), a state of the operation pedal (203) based on the position sensor signal (232) and the force sensor signal (231), wherein the state of the operation pedal (203) is one of a normal operating state and a fault state.The method of claim 1, wherein the actuation pedal (203) is a brake pedal.The method of claim 1, wherein the actuation pedal (203) is an accelerator pedal.The method of claim 1, further including performing a remedial action when the state of the actuation pedal (203) is a fault condition.The method of claim 4, wherein the remedial action is at least one of providing a notification of the fault condition, modifying braking of the vehicle (10), and modifying acceleration of the vehicle (10).The method of claim 1, wherein determining the state of the actuation pedal (203) includes determining that the actuation pedal (203) is in the fault state if the force sensor signal (231) indicates a non-zero force while the position sensor signal (232) indicates that the actuation pedal (203) has not moved beyond a sleep state.The method of claim 1, wherein determining the state of the actuation pedal (203) includes determining that the actuation pedal (203) is in the fault state when the force sensor signal (231) indicates a zero force while the position sensor signal (232) indicates that the actuation pedal has moved beyond a sleep state.A system for determining the pedal condition of a vehicle (10), the system comprising: a pedal actuation system having an actuation pedal (203), a force sensor assembly (202) configured to generate a force sensor signal (231) indicative of a force applied to the actuation pedal (203), and a position sensor assembly (206) configured to generate a position sensor signal (232) indicative of the position of the actuation pedal (203), the position sensor assembly (206) comprising an optical camera component positioned below a front dashboard of the vehicle (10) to determine the position of the actuation pedal (203); and a pedal state determination module (620) including a processor (44) configured to determine a state of the actuation pedal (203) based on the position sensor signal (232) and the force sensor signal (231), wherein the state of the actuation pedal (203) is one of a normal operating state and a fault state.The system of claim 8, wherein the actuation pedal (203) is a brake pedal.The system of claim 8, wherein the actuation pedal (203) is an accelerator pedal.

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