DIAGNOSTIC SYSTEM FOR A VEHICLE ENGINE-OPERATED MECHANISM AND METHOD USING A HALL EFFECT SENSOR

Abstract

A diagnostic system for diagnosing a motor-driven mechanism on board a vehicle includes a current detector for detecting current drawn by a motor of the motor-driven mechanism, a Hall effect sensor coupled to an output of the motor to generate a Hall effect position signal, and a controller configured to receive the detected motor current and Hall effect position signal and to determine an obstruction or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall effect sensor signal.

Description

FIELD OF DISCLOSUREThe present disclosure relates generally to diagnostic techniques for diagnosing a motor-driven mechanism on a vehicle, and more particularly relates to a vehicle engine diagnostic system and method that monitors and diagnoses the motor-driven mechanism with an engine and a Hall-effect sensor.GENERAL STATE OF THE ARTMotor vehicles are typically equipped with a variety of motor-driven mechanisms that include electric motors, such as direct current (DC) motors, for performing various actuations on the vehicle. For example, vehicle seats are typically operated with a motor-driven system to actuate a seat or seat component for movement to various positions and configurations. Motorized mechanisms may be used to translate the seat forward and rearward, up and down, into reclined positions, and for other operations. It would be desirable to provide a diagnostic system for diagnosing operation of a motor-driven mechanism onboard a vehicle.SUMMARY OF THE DISCLOSUREAccording to a first aspect of the present disclosure, a diagnostic system for diagnosing a motor-driven mechanism onboard a vehicle includes a current detector for detecting current drawn by a motor of the motor-driven mechanism, a Hall-effect sensor operatively coupled to an output of the motor for generating a Hall-effect position signal, and a controller configured to receive the detected motor current and the Hall-effect position signal and determine an obstacle or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall-effect sensor signal.Embodiments of the first aspect of the present disclosure may include any one or a combination of the following features:the motor comprises a DC electric motor;the controller detects an obstacle with an object based on the motor current exceeding a threshold and the Hall effect signal indicating a motion position between end-of-travel limits;the motor-driven mechanism comprises an electric motor and a transmission assembly;the controller detects a fault condition of the transmission assembly;the motorized mechanism is operatively coupled to an electrically adjustable seat;the motorized mechanism actuates a seat component;the controller detects an obstacle based on the motor current and the Hall effect signal; andthe controller detects a fault of the transmission assembly based on the motor current and the Hall effect signal.According to a second aspect of the present disclosure, a vehicle seat includes a seat bottom, a seat back, and a motor-driven mechanism having a motor and configured to actuate movement of the seat. The motor-driven mechanism includes a current detector for detecting current drawn by the motor, a Hall-effect sensor operatively coupled to an output of the motor for generating a Hall-effect position signal, and a controller configured to receive the detected motor current and the Hall-effect position signal and determine an obstacle or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall-effect sensor signal.Embodiments of the second aspect of the present disclosure may include any one or a combination of the following features:the motor comprises a DC motor;the controller detects an obstacle with an object based on the motor current exceeding a threshold and the Hall effect signal indicating a motion position between end-of-travel limits;the motor-driven mechanism comprises a motor and a transmission assembly;the controller detects one of a failure condition of the transmission assembly and a lack of hard stop;the motorized mechanism is operatively coupled to an electrically adjustable seat.The present disclosure also includes a method of detecting an obstacle or fault condition in an engine driven mechanism on a motor vehicle. The method includes detecting current drawn by a motor of the motor-driven mechanism, sensing a position of an output shaft of the motor with a Hall effect sensor, and generating a Hall effect position signal, and determining, with a controller, an obstacle or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall effect sensor signal.Embodiments of the third aspect of the present disclosure may include any one or a combination of the following features:the motor comprises a DC electric motor;the controller detects an obstacle with an object based on the motor current exceeding a threshold and the Hall effect signal indicating a motion position between end-of-travel limits;the motor drive assembly includes an electric motor and a transmission assembly; andthe controller detects a fault condition of the transmission assembly.These and other features, advantages and objects of the present disclosure will be better understood and understood by those skilled in the art by reference to the following description, claims and accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGSIn the drawings, the following applies: FIG. 1 is a front perspective view of a passenger compartment interior including a seat equipped with motor-driven mechanisms and a motor diagnostic system; FIG. 2 is a block diagram illustrating the engine diagnostic system for diagnosing operation of an electric motor-driven mechanism according to an example; FIG. 3 is a flow chart illustrating a routine for diagnosing the motor-driven mechanism including detecting an obstacle or one or more fault detections; and FIG. 4 is a schematic diagram illustrating detection zones of a Hall effect sensor for detecting the movement of the motor driven mechanism.DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSReference will now be made in detail to the present preferred embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar parts where possible. In the drawings, the structural elements depicted are not to scale and certain components are exaggerated relative to the other components for emphasis and understanding.As required, detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure that may be practiced in various and alternative forms. The figures do not necessarily correspond to a detailed configuration; some schematic representations can be shown in enlarged or reduced form in order to show a functional overview. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present disclosure.For purposes of description herein, the terms "top," "bottom," "right," "left," "rear," "front," "vertical," "horizontal," and derivatives thereof refer to the concepts in their orientation in FIG. 1, however, it should be understood that the concepts may assume various alternative orientations, unless expressly stated to the contrary. It is also to be understood that the specific devices and processes illustrated in the accompanying drawings and described in the following specification are merely exemplary embodiments of the inventive concepts defined in the appended claims. Thus, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.The presently illustrated embodiments are primarily in combinations of method steps and apparatus components associated with a system and method for diagnosing a vehicle engine driven mechanism using a Hall effect sensor. Accordingly, the apparatus components and method steps in the drawings have been represented by conventional symbols where appropriate, only those specific details relevant to understanding the embodiments of the present disclosure being shown in order not to obscure the disclosure with details readily apparent to those of ordinary skill in the art in light of the present description. Further, like reference numerals represent like elements throughout the specification and the drawings.As used herein, the term "and / or," when used in a listing of two or more items, means that each of the listed items may be used individually or any combination of two or more of the listed items may be used. For example, when a composition as described herein contains components A, B, and / or C, the composition may contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.In this specification, relational expressions such as first and second, upper and lower, and the like are used only to distinguish one entity or action from another entity or action without necessarily requiring or implying an actual such relationship or order between such entities or actions. It is intended that the terms "comprises," "comprising," or any other variation thereof cover a non-exclusive inclusion, such that a process, method, article, or device that / includes a enumeration of elements not only includes those elements, but may include other elements not expressly listed or inherent to such process, method, article, or device. An element preceded by "comprises... a / a / an" does not exclude, without further limitations, the presence of additional identical elements in the process, method, article, or apparatus comprising the element / s.As used herein, the term "about" means that amounts, sizes, formulations, parameters, and other quantities and properties are not accurate and need not be accurate, but may be approximately and / or greater or less, and may reflect tolerances, conversion factors, rounding off, measurement errors, and the like, and other factors known to those of ordinary skill in the art, if desired. When the term "about" is used to describe a value or an endpoint of a range, the disclosure should be understood to include the specific value or endpoint referred to. Regardless of whether a numerical value or an end point of a range includes "about" in the description, the numerical value or the end point of a range is intended to include two embodiments: one modified by "about" and one not modified by "about". It will be further understood that the endpoints of each of the ranges are significant with respect to both the other endpoint and independent of the other endpoint.It is intended that the terms "substantial", "substantially" and variations thereof, as used herein, indicate that a described feature is equal to or approximately equal to a value or description. For example, a "substantially planar" surface is intended to mean that a surface is planar or approximately planar. Moreover, "substantially" is intended to mean that two values are equal or approximately equal. In some embodiments, "substantially" may refer to values within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.As used herein, the terms "the," "the," or "a" or "an" mean "at least one(s)," and should not be limited to "only one(s)," unless expressly stated to the contrary. Thus, for example, reference to "a component" includes embodiments having two or more such components, unless the context clearly indicates otherwise.Referring to FIG. 1, generally illustrated is an example of an automobile or motor vehicle 10 having a body 12 defining a cabin interior 14, commonly referred to as a passenger compartment. The cabin interior 14 is configured to include one or more vehicle seats operated, such as front row seats located in a front row of seats as shown, and which may further include rear row seats located in one or more rear rows of seats. The vehicle seating assembly 20 may be a driver seat that is generally located behind a steering wheel 16 with respect to the vehicle and thus may serve as a seat of the driver of the motor vehicle 10 in the example shown. The seating assembly 20 includes a seat bottom 22 and a seat back 24 that can pivot relative to the seat bottom between an ascending and descending position. The seat surface 22 is mounted on a frame support 28 which is in turn operable on a rail 26. The rail 26 is supported on a floor 18 of the cabin interior 14. The rail 26 may allow the seating assembly 20 to move forward and rearward of the rail 26 relative to the vehicle. It should be appreciated that the motor vehicle 10 may include a plurality of powered seating assemblies, each powered seating assembly having a powered seat with a motor-powered mechanism that includes one or more electric motors for actuating the seat or seat components, as explained in the example shown herein.The seating assembly 20 in the example shown in FIG. 1 is equipped with a plurality of electric motor-driven mechanisms, thereby forming an actuated seat that can be actuated in one or more directions. Included is a first electric motor 30 configured to actuate and move the seat longitudinally in two directions between a front and rear position on the rail 26. The motor 30 may be actuated in response to a user input device 38, which may include, for example, a rocker switch shown at a location on a sidewall of the seat bottom 22. When a user actuates the rocker switch to the forward position, the first motor 30 drives the seat in the forward direction to a forward position. When a user actuates the user input 38 to command movement in the reverse direction, the first electric motor 30 drives the seating assembly 20 in the reverse direction to a rearward position. The first motor 30 may include a direct current (DC) motor that is part of a motor-driven mechanism having an output shaft 32 that can engage a first gear assembly 34 with one or more first gears and / or linkages to drive the support member 28 on the rail 26, and thus the seat, to a plurality of positions. Additionally, the first motor 30 includes a first Hall effect sensor 36 operatively coupled to the first motor 30, and more specifically coupled to the first motor shaft 32 to sense the position of the first motor shaft 32. Thus, by monitoring an output signal of the Hall-effect sensor 36, the position and movement of the seating assembly 20 on the rail 26 may be determined.The seating assembly 20 is also configured to include a second electric motor-operated assembly having a second electric motor 40, which in one example is configured to actuate the seat in two directions, namely up and down, between an upper position and a lower position. The second motor 40 may be a DC electric motor that actuates the seat in response to a user input device 48, which may include a rocker switch. When a user operates the user input device 48 with a seat raising command, the second electric motor 40 is operated to operate the seat upward. When a user actuates the user input device 48 with a downward movement command, the seating assembly 22 is moved downward with the second electric motor 40. The second electric motor 40 is part of a motor-driven mechanism configured to include a second electric motor shaft 42 that may interface with a second transmission assembly 44 having one or more second gears and / or linkages for electrically driving the seating assembly 20 between an upper and lower position. Additionally, to monitor a position of the second motor shaft 42 and thus a position of movement of the seating assembly 20 between the upper and lower positions, a second Hall effect sensor 46 is operatively coupled to the second motor shaft 42.It should be appreciated that the seating assembly 20 may include other electric motor-driven mechanisms with additional motors, each configured with a Hall-effect sensor. For example, a two-direction tilt motor coupled to a transmission assembly may tilt the seat back up in two directions up or down and a bolster may be actuated with a bolster motor and associated transmission assembly to move the bolsters. Thus, the seating assembly 20 may be a two-direction, four-direction, six-direction, eight-direction seat or an operated seat having a greater number of degrees of movement, each via a motor-driven mechanism. It will be further appreciated that the motor vehicle 10 may include other seating assemblies having one or more motor-driven mechanisms each equipped with a Hall-effect sensor.The motor vehicle 10 may include other motor-driven mechanisms configured to actuate other devices, each having motors onboard the vehicle, which may also include a Hall-effect sensor. For example, the motor vehicle 10 may include one or more motors and transmission assemblies operatively coupled to the steering wheel 16 to actuate the steering wheel 16 to one or more positions. According to other examples, the motor vehicle 10 may be equipped with engines and transmission assemblies configured to actuate one or more side view mirrors, foot pedals such as brake and accelerator pedals, and other engine-driven mechanisms.Each of the motor-driven mechanisms, including the first motor-driven mechanism and the second motor-driven mechanism, is configured to detect performance of the motor and associated mechanical actuation components, such as transmission assemblies and / or linkage assemblies, for diagnosing with a diagnostic system. For example, the diagnostic system may monitor and detect an obstacle in the travel path of the seating assembly 20 and may perform one or more control functions. The diagnostic system may also detect one or more fault conditions of the respective motor and associated drive assembly. For example, a fault condition such as seizure of the transmission assembly may be detected. Other fault conditions may include a loose or disassembled transmission assembly. Other fault conditions may include misalignment or eccentricity of a rotor of the electric motor, which may cause variations in the sensor output signals. It will be appreciated that certain fault conditions of the motor driven mechanisms may result in a loss of accuracy in the sensed seat position, which may be uncomfortable for users.Referring to FIG. 2, generally illustrated is the diagnostic system 90 having a controller 50 configured to monitor the electric motor and the Hall effect sensor and perform a diagnostic operation on the electric motor driven mechanisms. The controller 50 may include a microprocessor 52 and memory 62. A diagnostic routine 100 is stored within memory 62 and is executed by microprocessor 52. It should be appreciated that the controller 50 may include a shared or dedicated controller and may include other analog and / or digital circuitry. The controller 50 receives a sensed current from the DC motors 30 and 40. the controller 50 also receives the Hall count position signal from each of the Hall effect sensors 36 and 46. the controller 50 processes the sensed motor current and the sensed Hall effect signal and detects one or more obstacles and fault conditions of the electric motor and associated drive mechanism. The controller 50 may issue a warning 54 of an obstacle or fault condition of the motor driven mechanism. Additionally, the controller 50 may output a control signal 56, such as a signal to prevent vehicle operation during a particular diagnostic or event.Referring to FIG. 3, the diagnostic routine 100 is illustrated according to an example. The diagnostic routine 100 begins at step 102 and proceeds to step 104 to receive a command input via one of the user input switches to move the seat surface, referred to as the cushion, up or down and sets an object detection (OD) count equal to zero (0). Next, the routine 100 proceeds to step 106 to command the motor to rotate the seat cushion toward the target position. Thereafter, at decision step 108, routine 100 determines whether the sensed motor current is greater than a motor stall threshold and, if so, proceeds to decision step 110 to determine whether the sensed Hall count is within a range between HrdStpLowNom_max and HrdStpHighNom_min and, if so, reports barrier detection at step 112 and sets the OD count equal to OD+1, thereby incrementing the count. At decision step 114, routine 100 determines whether the OD count is greater than one (1) and, if not, proceeds to step 116 to command the motor to move the seat cushion in the opposite direction from up or down and returns to step 106 to command the motor to rotate the seat cushion toward the target system. If the OD count is greater than one (1) indicating a second actuation attempt, routine 100 proceeds to step 118 to command the motor to stop movement of the seat cushion and prompt the user to remove the barrier and retry the motorized actuation.If the count number of the Hall effect sensor is outside the range of HrdStpLowNom_max and HrdStpHighNom_min the routine 100 proceeds to each of the decision steps 120 and 126. At decision step 120, routine 100 determines whether the Hall effect sensor count is within a range between HrdStpLowNom_min and HrdStpLowNom_max and, if so, confirms at step 122 that the seat cushion position is down before ending at step 124. If the count number of the Hall effect sensor is outside the range of HrdStpLowNom_min and HrdStpLowNom_max routine 100 proceeds to step 130 to determine that an error is detected. This error may include a malfunction of the seat cushion mechanism, such as an interruption of the motion transmission of the system.At decision step 126, routine 100 determines whether the hall sensor count is within a range of HrdStpHighNom_min to HrdStpHighNom_max and, if so, confirms at step 128 that the seat cushion position is up before ending at step 124. If the Hall count is not within the range of HrdStpHighNom_min and HrdStpHighNom_max routine 100 proceeds to step 130 to determine that an error condition is detected. This error may include a malfunction of the seat cushion mechanism, such as an interruption of the motion transmission of the system.If the routine 100 determines at decision step 108 that the motor current is not greater than the motor stall threshold, the routine 100 proceeds to decision step 132 to determine if the motor current is less than a lower threshold. If the motor current is not less than the lower threshold, routine 100 proceeds to decision step 134 to determine whether the hall sensor count is greater than T H MIN, or whether the hall sensor count is less than T L MAX, and if so, proceeds to step 130 to determine that a fault condition has been detected. This error may involve a mechanical problem, such as a lack of hard stop.If it is determined in decision step 132 that the motor current is less than the lower threshold, routine 100 proceeds to decision step 136 to determine whether the hall sensor count is greater than a high T H MAX or whether the hall sensor count is less than a low T H MIN, and if so, proceeds to step 130 to determine that fault detection has occurred. This error may include partial or complete disengagement of the transmission assembly. If decision steps 134 or 138 are negative, routine 100 returns to step 106.The barrier detection zone and hard stop boundaries including T H MAX, T H MIN, T L MAX, and T L MIN are illustrated in FIG. 4. In addition, parameters HrdStpLowNom_min HrdStpLowNom_max HrdStpHighNom_min and HrdStpHighNom_max are also illustrated in FIG. 4. T L MIN is the count threshold of the Hall effect sensor beyond the lower limit of the hard stop at the lower position. T L MAX is the count threshold of the Hall effect sensor beyond the upper limit of the hard stop in the lower position. T H MIN is the count threshold of the Hall effect sensor beyond the lower limit of the hard stop in the upper position. T H MAX is the count threshold of the Hall effect sensor beyond the upper limit of the hard stop in the upper position. HrdStpLowNom_min is the lower limit of the nominal count threshold of the Hall effect hard stop sensor in the lower position. HrdStpLowNom_max is the upper limit of the nominal count threshold of the Hall effect hard stop sensor in the lower position. HrdStpHighNom_min is the lower limit of the nominal count threshold of the Hall effect hard stop sensor in the upper position. HrdStpHighNom_max is the upper limit of the nominal count threshold of the Hall effect hard stop sensor in the upper position.A barrier that creates an obstacle on the travel path may be detected within the barrier detection zone between the nominal end travel limits. Once the end-of-travel limits are reached, the motor current and the count signals of the Hall-effect sensor are detected to determine the possible fault condition of the motor and associated drive assembly.Accordingly, the diagnostic system 90 and method 100 advantageously provide barrier and fault detection of a motor-driven mechanism on a vehicle 10. The diagnostic system 90 and method 100 are particularly advantageous for detecting a barrier or motor fault associated with a motor-driven mechanism on a vehicle seating assembly on the vehicle 10. By employing the diagnostic system 90 and method 100, mechanical failures associated with the motor and drive assembly can be effectively detected, thereby improving overall seat positioning system reliability and precision, for example.It is to be understood that variations and modifications may be made to the foregoing construction without departing from the concepts of the present disclosure, and it is further to be understood that such concepts are intended to be covered by the following claims unless these claims expressly state otherwise by their language.According to the present invention, there is provided a diagnostic system for diagnosing a motor-driven mechanism onboard a vehicle, comprising: a current detector for detecting current drawn by a motor of the motor-driven mechanism; a Hall effect sensor operatively coupled to an output of the motor for generating a Hall effect position signal; and a controller configured to receive the detected motor current and the Hall effect position signal and determine an obstacle or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall effect sensor signal.According to one embodiment, the motor comprises a DC electric motor.According to one embodiment, the controller detects an obstacle with an object based on the motor current exceeding a threshold and the Hall effect signal indicating a position of movement between end-of-travel limits.According to one embodiment, the motor-driven mechanism includes an electric motor and a transmission assembly.According to one embodiment, the controller detects a fault condition of the transmission assembly.According to one embodiment, the motor-driven mechanism is operatively coupled to an electrically-adjustable seat.According to one embodiment, the motor-driven mechanism actuates a seat component.According to one embodiment, the controller detects an obstacle based on the motor current and the Hall effect signal.According to one embodiment, the controller detects a fault of the transmission assembly based on the motor current and the Hall effect signal.According to the present invention, there is provided a vehicle seat comprising: a seat bottom; a seat back; and a motor-driven motor comprising a motor and configured to actuate movement of the seat; a current detector for detecting current received by the motor; a Hall-effect sensor operatively coupled to an output of the motor to generate a Hall-effect position signal; and a controller configured to receive the detected motor current and the Hall-effect position signal and determine an obstacle or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall-effect sensor signal.According to an embodiment, the motor comprises a DC motor.According to one embodiment, the controller detects an obstacle with an object based on the motor current exceeding a threshold and the Hall effect signal indicating a position of movement between end-of-travel limits.According to one embodiment, the motor-driven mechanism includes a motor and a transmission assembly.According to one embodiment, the controller detects one of a transmission assembly fault condition and a lack of hard stop.According to one embodiment, the motor-driven mechanism is operatively coupled to an electrically-adjustable seat.According to the present invention, a method for detecting an obstacle or fault condition in a motor driven mechanism on a motor vehicle includes: detecting current drawn by a motor of the motor driven mechanism; detecting a position of an output shaft of the motor with a Hall effect sensor and generating a Hall effect position signal; and determining an obstacle or fault condition associated with the motor driven mechanism based on the detected motor current and Hall effect sensor signal with a controller.In one aspect of the invention, the motor comprises a DC electric motor.In one aspect of the invention, the controller detects an obstacle having an object based on the motor current exceeding a threshold and the Hall effect signal indicating a position of movement between end-of-travel limits.In one aspect of the invention, the motor-driven mechanism includes an electric motor and a transmission assembly.In one aspect of the invention, the controller detects a failure condition of the transmission assembly.

Claims

A diagnostic system for diagnosing a motor-driven mechanism onboard a vehicle, the diagnostic system comprising: a current detector for detecting current drawn by a motor of the motor-driven mechanism; a Hall-effect sensor operatively coupled to an output of motor for generating a Hall-effect position signal; and a controller configured to receive the detected motor current and the Hall-effect position signal and determine an obstacle or fault condition associated with the motor-driven mechanism based on the detected motor current and Hall-effect sensor signal.The diagnostic system of claim 1, wherein the motor comprises a DC electric motor.The diagnostic system of claim 1, wherein the controller detects an obstacle with an object based on the motor current exceeding a threshold and the Hall effect signal indicating a position of movement between end-of-travel limits.The diagnostic system of claim 1, wherein the motor-driven mechanism comprises an electric motor and a transmission assembly.The diagnostic system of claim 4, wherein the controller detects a fault condition of the transmission assembly.The diagnostic system of any of claims 1-5, wherein the motorized mechanism is operatively coupled to an electrically adjustable seat.The diagnostic system of claim 6, wherein the motorized mechanism actuates a seat component.The diagnostic system of claim 1, wherein the controller detects an obstacle based on the motor current.The diagnostic system of claim 1, wherein the controller detects a fault condition of a transmission assembly based on the Hall effect signal.A method of detecting an obstacle or fault condition in a motor driven mechanism on a motor vehicle, the method comprising: detecting current drawn by a motor of the motor driven mechanism; detecting a position of an output shaft of the motor with a Hall effect sensor and generating a Hall effect position signal; and determining an obstacle or fault condition associated with the motor driven mechanism based on the detected motor current and Hall effect sensor signal with a controller.

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