Rearview mirror assembly adjustment system

Abstract

A system for calibrating an in-vehicle driver monitoring system is provided. The present invention includes a rearview mirror assembly including a housing, a mount secured to a vehicle surface, and a barrel extending between the housing and the mount, an imaging device disposed within the rearview mirror assembly, a processor in communication with the imaging device, a memory including a file containing information regarding fixed landmarks proximate the imaging device, and a controller operable to receive images of the interior of the vehicle and calibrate the imaging device by identifying substantially fixed landmarks in a first image used during initial calibration, the controller being configured to recalibrate a driver monitoring operation based at least in part on detecting that the substantially fixed landmarks are in a different position in the second image relative to the first image. One of the ends of the barrel is connected to a movable joint.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 235,830, filed August 23, 2021, entitled "Camera-Based Rearview Assembly Orientation Adjustment System."

[0002] The present disclosure relates generally to processing images in a rearview mirror assembly, and more particularly to processing images captured by an imaging device in a driver monitoring system in a rearview mirror assembly. [Background technology]

[0003] One or more imaging devices may be attached to a rearview mirror assembly for a driver monitoring system and may be specifically configured to capture images of the vehicle driver or specific body parts of the driver. This may enable the driver monitoring system to accurately determine the driver and the driver's eye position for monitoring purposes. The driver monitoring system may be calibrated with the rearview mirror assembly in a given position. Once the driver monitoring system is calibrated, subsequent adjustments of the rearview mirror assembly must be detected and quantified so that appropriate corrections can be applied to the captured images. Existing sensors can be used to directly measure the adjustment of the rearview mirror assembly, but they are expensive. Summary of the Invention

[0004] According to one aspect, a system for calibrating a driver monitoring system in a vehicle includes a rearview mirror assembly including a housing and a mount secured to a vehicle surface, and a barrel extending between the housing and the mount, the barrel having a first end and a second end; an imaging device capable of capturing images, the imaging device disposed within the rearview mirror assembly; a processor in communication with the imaging device; a memory in communication with the processor, the memory including a file containing information about fixed landmarks proximate to the imaging device; and a controller operable to receive an image of the vehicle interior and calibrate the imaging device. The calibration may include identifying a substantially fixed landmark in a first image used during initial calibration. The controller may be configured to recalibrate driver monitoring operation based at least in part on detecting that the substantially fixed landmark is in a different position in the second image relative to the first image. At least one of the first end and the second end of the barrel may be connected with a movable joint.

[0005] The captured image of the interior of the rearview mirror assembly may include at least one fixed image landmark. The at least one fixed image landmark may be disposed within the housing. A first end of the barrel may have a movable joint connected to the mount. A second end of the barrel may have a movable joint connected to the housing. The file may include information regarding the fixed landmark within the housing of the rearview mirror assembly.

[0006] The controller may be configured to import the image and identify image features that are known from the file. The controller may be configured to determine the location of the features based on information in the file. The controller may be configured to define a coordinate system based on one or more joints at the end of the barrel. The imaging device may be configured to correlate the captured image with the file to determine the relative position of the rearview mirror assembly with respect to its original position. The controller may be configured to determine the coordinate system based on one or more joints that secure the rearview mirror assembly to the vehicle. The controller may be configured to identify at least one feature in the file and find the same at least one feature in the rearview mirror assembly. The controller may be configured to determine five angles, including two pitch angles, two yaw angles, and one roll angle, using the position of the at least one feature. The controller may be configured to calculate the position and orientation of the rearview mirror assembly based on the determination of the five angles. The controller may be configured to recalibrate the driver monitoring system using the new position and orientation information.

[0007] According to one aspect, a method for calibrating a driver monitoring system may include providing a rearview mirror assembly having a driver monitoring system comprising an imaging device and a memory containing a file containing details regarding the interior structure of the rearview mirror assembly, including the locations of a plurality of fixed landmarks within a housing of the rearview mirror assembly; capturing an image of the interior of the rearview mirror assembly using the imaging device; comparing the captured image with the file stored in the memory containing details of the interior structure of the rearview mirror assembly; and calibrating the driver monitoring system using information obtained from the comparison between the captured image and the stored image.

[0008] The method may further include establishing image coordinates of fixed landmarks within the rearview mirror assembly. The method may further include defining an initial rotation as 0,0,0 during initial calibration of the driver monitoring system. The method may further include dewarping the captured image and establishing new image coordinates for the plurality of fixed landmarks. The method may further include determining alignment information for the rearview mirror assembly. The method may further include applying the alignment information to the captured image. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 illustrates a block diagram of a camera-based adjustment system for a driver monitoring system according to the present disclosure. [Figure 2] FIG. 2 shows a top view of a rearview mirror assembly according to the present disclosure. [Figure 3] FIG. 3 is a side view of the rearview mirror assembly of FIG. [Figure 4] FIG. 4 is a top rear perspective view of one embodiment of a rearview mirror assembly according to the present disclosure. [Figure 5] FIG. 5 is a plan view of an embodiment according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] 1 , a system for calibrating a driver monitoring system is generally designated by the reference numeral 10. Calibration system 10 may include a driver monitoring system 20 disposed within a rearview mirror assembly 24. Driver monitoring system 20 may include a camera or imaging device 28, a processor 32, and a memory 36. Calibration system 10 may further include a computer-aided design (CAD) file 40 disposed within memory 36 that includes details of fixed landmarks visible to the imaging device, such as the internal structure of rearview mirror assembly 24.

[0011] 2-3 , the rearview mirror assembly 24 may include a mount 44, a housing 48, and a barrel 52 extending between the mount 44 and the housing 48. The rearview mirror assembly 24 may generally be designed to be supported on the windshield or roof of a vehicle (not shown) via the mount 44. The mount 44 may be fixedly connected to the vehicle's windshield or roof via a button (not shown) or other suitable connection element.

[0012] The barrel 52 may have a circular, oval, square, rectangular, or irregular cross-section. The barrel 52 may have a first end 52A and a second end 52B and may extend between the mount 44 and the housing 48 of the rearview mirror assembly 24. In some embodiments, the first end 52A of the barrel 52 may be pivotally connected to the mount 44 with a ball mount or other suitable connecting element. In some embodiments, the first end 52A of the barrel 52 may be fixedly connected to the mount 44.

[0013] Similar to the barrel and first end, in some embodiments, the second end 52B of the barrel 52 may be pivotally connected to the housing 48. The second end 52B of the barrel 52 may be connected to the housing 48 with a ball mount (not shown) or other type of mount that may be operably coupled with the rearview mirror assembly 24. The ball mount may be defined as part of the housing 48 or may be formed on a rear wall disposed inside the housing 48. Other possible configurations for the ball mount of the housing 48 are also contemplated. In some embodiments, the second end 52B of the barrel 52 may extend directly and fixedly from the housing 48.

[0014] Thus, the housing 48 of the rearview mirror assembly 24 may be configured to be movably mounted to the mount 44 (i.e., may rotate along a horizontal and / or vertical axis). The rearview mirror assembly 24 may have a single movable joint at either the first end 52A of the barrel 52 and the mount 44 or the second end 52B of the barrel 52 and the housing 48, or may have two movable joints, one at the first end 52A of the barrel 52 and the mount 44 and one at the second end 52B of the barrel 52 and the housing 48.

[0015] 4 and 5, the housing 48 may define an opening 56 having at least one of a reflective element, such as an electrochromic element, and a display element 60 configured to cover the opening 56. The rearview mirror assembly 24 may also include at least some components of a driver monitoring system 20 configured to perform driver monitoring functions. The components of the driver monitoring system 20 may include, but are not limited to, the image capture device 28, the processor 32, at least one light source 64, at least one printed circuit board (PCB) 68, and a controller 72. The processor 32 may be an image signal processor.

[0016] The image capture device 28 may be disposed inside the housing 48 and may be located behind the reflective element and / or display element 60. The image capture device 28 may include a lens 76 and an image sensor 80, such as a complementary metal-oxide semiconductor ("CMOS"), capable of generating image data upon activation. When the driver monitoring system 20 is operating, the image capture device 28 may be configured to capture one or more images of the driver's features and generate image data corresponding to the one or more captured images. The image capture device 28 may capture images of the driver intermittently or continuously. The driver monitoring system 20 may monitor and capture images of at least one of predetermined facial, head, and body features or positions of the driver. In some embodiments, the captured images may include, but are not limited to, the driver's eye pupil position and movement, blink frequency and duration, eyelid position, head position and orientation, head movement, pulse rate, face and eye movement, or other suitable driver performance indicators.

[0017] The imaging device 28 may further have the ability to detect image points within the rearview mirror assembly 24 and associate them with a CAD file 40 of the interior portion of the rearview mirror assembly 24. The CAD file 40 may include details of the interior structure of the rearview mirror assembly 24, such as supports, and other interior features. The driver monitoring system 20 may be initially calibrated with the rearview mirror assembly 24 in a given position. Any subsequent adjustments to the position of the rearview mirror assembly 24 may need to be detected and quantified so that appropriate corrections can be applied.

[0018] The imaging device 28 may be configured to capture images of fixed image landmarks in images captured when the driver monitoring system 20 was initially calibrated. When any change in the position of the landmarks is detected, the driver monitoring system 20 may need to be recalibrated. The images captured during calibration may be distortion corrected. Image coordinates for each landmark may be established. The world coordinate system may be defined as (0,0,0) at the focal point of the imaging device 28, with rotation defined as (0,0,0) when the driver monitoring system 20 was initially calibrated. From here, analogous world coordinates may be calculated for each of the image coordinates. The new images may be distortion corrected, and image coordinates may be established for each of the landmarks.

[0019] The at least one light source 64 may comprise an infrared light source or a near-infrared (NIR) light source. The at least one light source 64 and the imager 28 may be electrically coupled to a PCB 68 and may further communicate with a controller 72. In some embodiments, the at least one light source 64 may be configured to have an illumination field that includes a driver position within the vehicle.

[0020] The processor 32 may be capable of processing images captured by the image capture device 28. The processor 32 may be a general or application-specific processor or circuit for calculating, handling input, generating output, and / or otherwise performing computational tasks. The processor 32 may be a microprocessor configured using various components, such as a field programmable gate array (FPGA) or a combination of discrete and FPGA components. In some embodiments, the processor 32 may be adapted to perform multiple functions. These functions may include, but are not limited to, headlamp control, lane departure warning, and other driver assistance functions. The processor 32 may be configured to selectively activate the light sources 64 and process image data received from the image capture device 28 to monitor the driver. In some embodiments, the processor 32 may process the captured images to generate image data related to driver characteristics. The generated image data may include, for example, blink rate, blink duration, head position and orientation, eye position, pulse rate, or other suitable driver performance indicators.

[0021] The controller 72 may be located on the PCB 68, elsewhere in the housing 48, or elsewhere in the vehicle. The controller 72 may be in communication with the processor 32. The controller 72 may be in communication with various devices integrated into the rearview mirror assembly 24 and / or the vehicle's equipment. The controller 72 may be in communication with the processor 32. The controller 72 may be configured to selectively activate the at least one light source 64 to project illumination onto selected illumination targets and may further be configured to cause image capture by the imaging device 28.

[0022] For example, an image from a scene, such as the scene behind the vehicle, may be captured by imaging device 28 and shown on display element 60 of rearview mirror assembly 24. The driver of the vehicle may adjust the position of rearview mirror assembly 24 to avoid blind spots and to ensure that the driver can easily view images from the desired field of view of rearview mirror assembly 24.

[0023] The driver monitoring system 20 of the rearview mirror assembly 24 may be initially calibrated at its initial position and orientation. This allows the driver monitoring system to determine, among other things, where the driver is looking. However, if the rearview mirror assembly 24 moves, the driver monitoring system 20 may not be able to accurately determine what the driver is looking at. After the rearview mirror assembly 24 moves from its initial position, any adjustments made to the position of the rearview mirror assembly 24 need to be detected and quantified. Recalibration of the driver monitoring system 20 to correct for changes in position and / or orientation may be desirable. Detecting and quantifying subsequent adjustments of the rearview mirror assembly 24 after the initial positioning may allow appropriate corrections to be applied.

[0024] The imaging device 28 for the driver monitoring system 20 and image data captured by the imaging device 28 may be used to accomplish this function. The imaging device 28 may image and register fixed landmarks in images taken when the imaging device 28 was initially calibrated. If subsequent adjustments are made to the position and / or orientation of the rearview mirror assembly 24, the landmark positions in the images will change, and these changes can be used to quantify the adjustments made to the rearview mirror assembly 24. When changes in the landmark positions in the images are detected, corrections may be determined and applied.

[0025] The CAD file 40 of the rearview mirror assembly 24 may include details of the interior portions of the rearview mirror assembly 24, may include details of the interior of the housing 48, including any ribs or supports, and other information. The imaging device 28 may be configured to capture images of the interior of the rearview mirror assembly 24 and to capture images of external landmarks, and may compare the images and landmarks to the images stored in the CAD file 40.

[0026] The controller 72 may be configured to import an image and identify known image features from the CAD drawing. The controller 72 may be configured to determine the location of features based on information in the CAD file 40. The controller 72 may define a coordinate system based on one or more junctions at either end 52A, 52B of the barrel 52. The controller 72 may be configured to estimate five angles: pitch, yaw, and roll angles at a first junction at one end of the barrel 52, and pitch and yaw angles at the other end of the barrel 52. All roll may be attributed to the first junction. The first junction may be at one of the first end 52A and the second end 52B of the barrel 52, and the second junction may be at the other of the first end 52A and the second end 52B of the barrel 52. If the rearview mirror assembly 24 has only one joint (i.e., one end 52A, 52B of the barrel 52 is fixed and the other end 52B, 52A of the barrel 52 is fixed via a joint), the controller 72 may be configured to assume that both joints are in the same position, or to assume that there are two joints but one joint is not movable.

[0027] The controller 72 may be configured to associate the captured images with the CAD file 40 to determine the relative position of the rearview mirror assembly 24 with respect to its original position. The inherent characteristics of the imaging device 28, such as the focal length, are known. Using that information and image data from the captured images, the controller 72 may be able to calculate angles based on the images captured by the imaging device 28, and may use the calculated angles to determine the precise position and orientation of the rearview mirror assembly 24.

[0028] In some embodiments, the rearview mirror assembly 24 may house an imaging device for a driver monitoring system. The imaging device may be initially calibrated while the rearview mirror assembly 24 is in a specific position. Any subsequent adjustments to the rearview mirror assembly 24 may need to be detected and quantified to apply the appropriate corrections to allow the imaging device to match the initial calibration. Detailed CAD drawings of the interior of the housing are available to determine the required calibration. Using the CAD drawings may enable the precise location of internal features to be determined.

[0029] To proceed from the image captured by the imaging device 28 to the angles calculated by the controller 72 and determine the position and orientation of the rearview mirror assembly 24, the controller 72 may be configured to define a coordinate system based on the joints that secure the rearview mirror assembly 24 to the vehicle. The controller 72 may be further configured to identify at least one feature in the CAD file 40 and find the same feature or features in the rearview mirror assembly 24. The controller 72 may then be configured to use that information to determine five angles (two pitch angles, two yaw angles, and one roll angle). Once the angles are determined, the controller 72 may be configured to calculate the precise position and orientation of the rearview mirror assembly 24. The controller 72 may then be configured to recalibrate the driver monitoring system 20 using the new position information.

[0030] The barrel 52 extending between the mount 44 and the housing 48 may be assumed to have a joint at each end. The joint at the end of the barrel 52 of the housing 48 of the rearview mirror assembly 24 may be referred to as "joint 1," and its center may be considered the origin of the coordinate system ([x,y,z]=[0,0,0]). +z may point to the rear of the vehicle, +y may point downward toward the road, and +x may point sideways toward the driver's side of the vehicle. The axes may be aligned with the long axis of a CAD drawing of the interior of the housing.

[0031] During initial calibration, images may be captured and at least one fixed image landmark may be identified. The at least one landmark may be located within a housing of the rearview mirror assembly. Subsequent images may be captured and the location of the at least one landmark may be determined. In some embodiments, the location of an end point of at least one of the landmarks may be determined. Motion of the at least one landmark may be determined. If a change in the location of one or more landmarks is detected, the following steps may be applied to recalibrate the imaging device.

[0032] During calculations, for simplicity, the focal point of the camera may be assumed to be at the center of the adjustable ball joint of the rearview mirror assembly 24. Images captured during initial calibration may be dewarped and image coordinates may be established for each of the at least one landmark. A coordinate system may be defined having a point (0,0,0) at the focal point of the imaging device and a rotation of (0,0,0). Analogous coordinates may then be calculated for each established image coordinate. Once the analogous coordinates are calculated, a new image may be dewarped and new image coordinates may be established for each of the at least one landmark. The new image coordinates may be used to calibrate the imaging device.

[0033] Memory 36 may be configured to store predetermined parameters for selected driver characteristics for use by driver monitoring system 20 while monitoring the driver.

[0034] In some embodiments, controller 72 may compare image data generated from images captured during driver monitoring mode to predetermined parameters for selected driver characteristics. In some embodiments, controller 72 may include predetermined thresholds for acceptable deviations between the captured images and the predetermined parameters. After comparing the generated image data to the predetermined parameters, controller 72 may determine whether the driver exhibits any symptoms that may indicate a decline in performance.

[0035] In some embodiments, controller 72 may compare image data generated from images captured during driver monitoring mode with image data generated from previously captured images. The previously captured images may be stored in memory 36 of processor 32 of driver monitoring system 20. In some embodiments, controller 72 may include a predetermined threshold for an acceptable deviation between the captured images and stored images or image data. After the comparison, controller 72 may determine whether there are signs that the driver's performance may be deteriorating.

[0036] A method 100 for calibrating the imaging device 28 when any changes in landmark positions within an image are detected may include the following steps. In step 110, the imaging device 28 may capture an image of an interior portion of the housing 48 of the rearview mirror assembly 24. From the CAD drawing, the controller 72 may determine potentially fixed line segments within the camera's field of view and may determine the endpoints of these segments in terms of a coordinate system. In a given image frame of the captured image, the controller 72 may locate some or all of these fixed segments and note the endpoints of these segments within the image domain.

[0037] In step 120, images captured during calibration may be distortion corrected. Assuming there are "N" landmarks, in step 130, image coordinates for each of the N landmarks may be established. In step 140, a world coordinate system may be defined as 0,0,0 at the focal point of the imager 28. In step 150, an initial rotation may be defined as 0,0,0 when the driver monitoring system 20 was calibrated. In step 160, this information may be used to calculate analogous world coordinates for each of the image coordinates mentioned in step 130. In step 170, new images may be distortion corrected and new image coordinates may be established for each of the "N" landmarks. Alignment information may be determined for the rearview mirror assembly 24 in step 180. In step 190, the controller 72 may apply the alignment information to images captured by the imager 28. The positioning information can be used not only by applications performed by the rearview mirror assembly 24 itself, such as driver monitoring, but can also be combined with the global vehicle orientation to know its orientation relative to the Earth.

[0038] As used herein, a "rearview mirror assembly" is a structure capable of providing an image of the scene behind the driver. The rearview mirror assembly may additionally or alternatively include an electronic display element 60 that displays an image sensed by a rear-facing camera or imaging device (see, for example, U.S. Patent No. 6,550,949, entitled "SYSTEMS AND COMPONENTS FOR ENHANCING REAR VISION FROM A VEHICLE," filed September 15, 1998, by Frederick T. Bauer et al., assigned to the assignee of the present application, the entire disclosure of which is incorporated herein by reference). Additionally or alternatively, the rearview mirror assembly may include both an electro-optical rearview mirror assembly and a display element 60 for providing an image from the rear-facing camera or imaging device 28. Thus, the rearview mirror assembly need not include a mirror element. In the embodiments described below, a rearview mirror assembly is shown and described.

[0039] The rearview mirror assembly may include at least one of a rearview mirror device and video display element 60 mounted in a housing 48, and a mount 44 that mounts the housing 48 to the vehicle. The various components described below may be mounted in the housing 48 of the rearview mirror assembly 24 or in the mount 44, with appropriate electrical connections made therebetween.

[0040] In some embodiments, the mount 44 may be configured to engage with a button (not shown) fixedly attached to the vehicle windshield or roof. However, it is contemplated that the mount 44 may engage with a button or other connector fixed to the vehicle in a variety of other manners, including twist-fit or interference-fit connections. It is also contemplated that the mount 44 may be fixed to the vehicle in a variety of other manners. It is also generally contemplated that other rearview mirror assembly features may be included in the rearview mirror assembly 24. Some of these additional devices may include a light sensor, a rain sensor, a compass, a microphone, etc. In some embodiments, the rearview mirror assembly 24 may further include an ambient light sensor (not shown) and a glare sensor (not shown).

[0041] The rearview mirror assembly 24 may be designed to mount directly to the vehicle windshield. Alternatively, the rearview mirror assembly 24 may be designed to mount to the roof of the vehicle. As will be apparent to those skilled in the art from the following description of various functions, the driver monitoring system 20 embodied in the rearview mirror assembly 24 may include various combinations of the elements identified above and, therefore, need not include each and every element shown and described. Furthermore, while each of the elements may be housed within the rearview mirror assembly 24, some or all of the components may be provided at other remote locations and may transmit and receive information via a vehicle bus or via RF transmission.

[0042] The above description is considered to be of the preferred embodiments only. Modifications of this disclosure will occur to those skilled in the art and to those who make or use this disclosure. It is therefore understood that the embodiments shown in the drawings and described above are for illustrative purposes only and are not intended to limit the scope of this disclosure, which is defined by the following claims, interpreted in accordance with the principles of patent law, including the doctrine of equivalents. While this disclosure has described in detail only a few embodiments of the innovations, those skilled in the art who review this disclosure will readily recognize that numerous modifications (e.g., changes in the size, dimensions, structure, shape, and proportions of various elements, parameter values, mounting arrangements, use of materials, color, orientation, etc.) are possible without materially departing from the novel teachings and advantages of the described subject matter. For example, elements shown as integrally formed may be comprised of multiple pieces, or elements shown as multiple pieces may be integrally formed, operation of interfaces may be reversed or otherwise changed, the structure of the system and / or the length or width of members or connectors or other elements may be changed, and the nature or number of adjustment points provided between elements may be changed. Accordingly, all such modifications are intended to be included within the scope of the innovation. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the innovation.

[0043] In this document, relationship terms, such as first and second, top and bottom, front and back, left and right, vertical, horizontal, etc., are used solely to distinguish one component or operation from another and do not necessarily require or imply any actual relationship, order, or number between such components or operations. These terms are not intended to limit the elements they describe, as various elements may be adapted differently in various applications. Moreover, unless expressly specified to the contrary, it should be understood that devices may assume various adaptations and sequences of steps. It should also 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. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered limiting, unless the claims expressly state otherwise.

[0044] It should be understood that any described process or step within a described process may be combined with other disclosed processes or steps to form structures within the scope of the present disclosure. The exemplary processes disclosed herein are for illustrative purposes and should not be construed as limiting. It should also be understood that variations and modifications can be made to the methods described above without departing from the concepts of the present disclosure, and further, it should be understood that such concepts are intended to be covered by the following claims unless the language in those claims expressly states otherwise.

[0045] As used herein, the term "and / or," when used in the context of a list of two or more items, means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as containing components A, B, and / or C, the composition can 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.

[0046] As used herein, the term "about" means that amounts, sizes, formulations, parameters, and other quantities and characteristics are not or need not be exact, but may be approximate and / or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding, measurement error, etc., and other factors known to those skilled in the art. When the term "about" is used in describing a value or the endpoint of a range, it should be understood that the disclosure includes the specific value or endpoint referred to. Regardless of whether a numerical value or range endpoint herein is described as "about," the endpoint of the numerical value or 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 both in relation to the other endpoint and independently of the other endpoint.

[0047] As used herein, the terms "substantial," "substantially," and variations thereof are intended to note that a described feature is equal to or approximately equal to a value or description. For example, a "substantially flat" surface is intended to indicate a flat or approximately flat surface. Furthermore, "substantially" is intended to indicate that two values ​​are equal or approximately equal. In some embodiments, "substantially" may refer to values ​​within at least one of 2% of each other, 5% of each other, and 10% of each other.

Claims

1. 1. A system for calibrating a driver monitoring system in a vehicle, comprising: a rearview mirror assembly comprising a housing and a mount, the mount being secured to a vehicle surface; and a barrel having a first end and a second end and extending between the housing and the mount; an imaging device capable of capturing an image, the imaging device being disposed within the rearview mirror assembly; a processor in communication with the imaging device; a memory in communication with the processor, the memory including a file containing information about fixed landmarks proximate the imaging device; a controller, receiving an image of the vehicle interior including the interior of the rearview mirror assembly having at least one fixed landmark disposed within the housing; a controller operable to calibrate the imaging device, the calibration including identifying a substantially fixed landmark in a first image used during initial calibration; The system, wherein the controller is configured to recalibrate driver monitoring operation based at least in part on detecting that the substantially fixed landmark is in a different position in the second image relative to the first image.

2. The system of claim 1 , wherein the file includes information regarding fixed landmarks within the housing of the rearview mirror assembly.

3. The system of claim 1 , wherein the first end of the barrel has a movable joint connected to the mount.

4. The system of claim 1 , wherein the second end of the barrel has a movable joint connected to the housing.

5. the controller is configured to import an image and identify at least one image feature in the image that corresponds to one of the fixed landmarks included in the file; the controller is configured to determine the location of the feature based on the information in the file; The system of claim 1 , wherein the controller is configured to define a coordinate system based on a single or multiple joints at an end of the barrel.

6. The system of claim 1 , wherein the controller is configured to correlate captured images with the file to determine a relative position of the rearview mirror assembly with respect to the initial calibration.

7. The system of claim 1 , wherein the controller is configured to determine a coordinate system based on a joint or joints that secure the rearview mirror assembly to the vehicle.

8. The system of claim 7 , wherein the controller is configured to identify at least one feature in the file and locate the same at least one feature in the rearview mirror assembly.

9. The system of claim 8 , wherein the controller is configured to determine five angles using the position of at least one feature, including two pitch angles, two yaw angles, and one roll angle.

10. The system of claim 9 , wherein the controller is configured to calculate the position and orientation of a rearview mirror assembly based on the determination of the five angles.

11. The system of claim 10 , wherein the controller is configured to recalibrate the driver monitoring system by comparing the position of the substantially fixed landmark in the second image with the first image.

12. 1. A method for calibrating a driver monitoring system, comprising: providing a rearview mirror assembly having a housing and a driver monitoring system, the driver monitoring system comprising an imaging device and a memory containing a file containing details regarding the internal structure of the rearview mirror assembly, including the locations of a plurality of fixed landmarks within the housing of the rearview mirror assembly; capturing an image of the interior of the rearview mirror assembly using the imaging device; comparing the captured image with a file stored in a memory containing details regarding the internal structure of the rearview mirror assembly; and calibrating the driver monitoring system using information obtained from the comparison between the captured image and the stored image.

13. The method of claim 12 further comprising establishing image coordinates of the fixed landmark within the rearview mirror assembly.

14. The method of claim 12 , further comprising defining an initial rotation as 0,0,0 during an initial calibration of the driver monitoring system.

15. The method of claim 14 , further comprising: correcting the captured image for distortion; and establishing new image coordinates for a plurality of the fixed landmarks.

16. The method of claim 15 further comprising determining position adjustment information for the rearview mirror assembly.

17. The method of claim 16 , further comprising applying alignment information to the captured image.

Images