Patent Publication Number: US-2019184909-A1

Title: Photographing Device Mounted on Vehicle and Photographing Method in Vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from Japanese Patent Application No. 2017-239722 filed on Dec. 14, 2017, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a photographing device mounted on a vehicle and a photographing method in a vehicle. 
     Description of Related Art 
     A vehicle safety technique is developed that the face of a driver who is driving a vehicle is photographed to monitor sleepiness, fatigue and a looking-away driving of the driver and ensure the safety of the vehicle. 
     For instance, Patent Literature 1 discloses, as a device which realizes the vehicle safety technique for detecting the sleepiness or the fatigue of the driver, a device having a photographing unit (a camera) which photographs an image to be photographed including the face of the driver to estimate a degree of awakening of the driver based on an image photographed by the camera. 
     Further, Patent Literature 2 discloses a device including a photographing unit (a camera) which photographs the eye of a driver, a line of vision detection unit which detects the line of vision of the driver from a photographed image of the camera and a movement of line of vision measuring unit which measures the movement of the line of vision of the driver in order to prevent the looking-away driving of the driver, in which a frequency that the line of vision of the driver directed to a preset carefully watching direction is lower than a frequency as a reference, an alarm is raised that a visual recognition of the driver is insufficient. 
     [Patent Literature 1] JP-A-2008-167806 
     [Patent Literature 2] JP-A-2006-224700 
     In a photographing device mounted on a vehicle, a face of a driver needs to be assuredly caught and photographed. According to a related art, when the face of the driver cannot be caught, a driving state of a driver such as sleepiness, fatigue and the looking-away driving of the driver cannot be monitored by a device. Thus, the device hardly contributes to the safety of the vehicle. Further, when a camera is mounted on a meter panel, a steering wheel is provided between the camera and the driver. Accordingly, the camera photographs the face of the driver through an opening part of the steering wheel. However, according to circumstances, the steering wheel may possibly form a dead angle. 
     Further, a study or a development of a mechanism or a function which is mounted on a vehicle to control or support an automatic driving is advanced. For instance, an electronic control unit (ECU) of the vehicle is constructed so as to meet an automatic driving of a level 2 (LV2) or a level 3 (LV3) of an automation level prescribed by the Japanese government or US Ministry of Transport Road Traffic Safety Bureau (NHTSA). In the level 2, a system automatically carries out a plurality of operations of acceleration, a steering and a brake of the vehicle. In the level 3, since the system carries out all the controls of the acceleration, the steering and the brake of the vehicle, the driver may ordinarily merely monitor a state of the driving. 
     However, even in the level 3, when the system makes a request at the time of emergency or limitation of the system, the driver must hand over (H/O) the automatic driving to a manual operation in accordance with this request. Accordingly, the photographing device mounted on the vehicle always needs to catch the face of the driver even in the level 3 during a shift to the level 2 from the level 3, namely, in preparation for the hand over. Then, in the level 3, it is well supposed that the driver cannot completely rest, however, the driver relaxes more than an ordinary time, so that a seated position may be possibly loose. 
     Here, when the face of the driver is located at a standard position even in the level 3, the camera can catch the face of the driver even at the time of the hand over. However, as described above, when the driver relaxes in the level 3 and the position of the face is excessively changed, the face may possibly deviate from a photographing range of the camera depending on the position of the camera or the opening part of the steering wheel, so that the face may not be possibly photographed by the usual photographing device mounted on the vehicle. In this case, the photographing device mounted on the vehicle cannot exhibit its function and may not possibly carry out a hand over at the time of emergency. 
     Further, according to a study, when the photographing device mounted on the vehicle judges that the face of the driver cannot be photographed, an alarm is given by a lamp or an audio as a fail-safe function. However, the automatic driving which is originally to be comfortable for the driver may be possibly complicated. 
     SUMMARY 
     One or more embodiments provide a photographing device mounted on a vehicle and a photographing method in a vehicle by which the face of a driver can be assuredly caught and photographed. 
     In an aspect (1), one or more embodiments provide a photographing device mounted on a vehicle, including a photographing part which is mounted on the vehicle to photograph a face of a driver, a wheel position adjusting part which adjusts a position of a steering wheel mounted on the vehicle, a photographing position adjusting part which adjusts at least one of a photographing position of the photographing part and a photographing angle of the photographing part, and a position adjusting control part which controls at least one of the wheel position adjusting part and the photographing position adjusting part based on a photographed result of the photographing part. 
     In an aspect (2), the photographing device mounted on the vehicle, further includes an image generating part which generates a photographed image based on the photographed result of the photographing part and an image judging part which judges whether or not the face of the driver is included in the photographed image based on the photographed image of the image generating part. The position adjusting control part controls at least one of the wheel position adjusting part and the photographing position adjusting part so as to include the face of the driver in the photographed image based on the judged result of the image judging part. 
     In an aspect (3), the position adjusting control part compares the photographed image at present with the photographed image in a past to detect a displacement of the face of the driver and control at least one of the wheel position adjusting part and the photographing position adjusting part based on the displacement. 
     In an aspect (4), a photographing method in a vehicle, includes photographing a face of a driver in a photographing part mounted on the vehicle, generating a photographed image based on a photographed result in the photographing, judging whether or not the face of the driver is included in the photographed image, and adjusting at least one of a position of a steering wheel mounted on the vehicle, a photographing position of the photographing part, and a photographing angle of the photographing part so as to include the face of the driver in the photographed image based on a judged result in the judging. 
     In an aspect (5), the adjusting includes comparing the photographed images of two times in a past with each other to detect a displacement of the face of the driver and adjusting at least one of the position of the steering wheel, the photographing position of the photographing part, and the photographing angle of the photographing part based on the displacement. 
     According to the aspect (1), even when a position of the face of the driver is excessively changed, the face of the driver can be caught by a photographing part. Namely, according to the photographing de vice mounted on the vehicle of the present invention, a position adjusting control part is provided which controls at least one of a wheel position adjusting part and a photographing position adjusting part based on the photographed result of the photographing part. Thus, even when the position of the face of the driver is excessively changed, the face of the driver can be caught by the photographing part. Further, a dead angle range of the photographing part is reduced, so that it is rarely necessary to inform of an alarm that a photographing operation cannot be made. Accordingly, since the driver does not need to constantly care about a seated position, a comfortableness of the driver in the vehicle is not harmed. 
     According to the aspect (2), it is judged whether or not the face of the driver is included in a photographed image to adjust at least one of a position of a steering wheel, a photographing position of the photographing part and a photographing angle of the photographing part so as to include a face of the driver in the photographed image. Thus, even when the position of the face of the driver is excessively changed, the face of the driver can be efficiently and self-consciously caught. 
     According to the aspect (3), a present photographed image is compared with a past photographed image to detect a displacement of the face of the driver and adjust at least one of the positions of the steering wheel, the photographing position of the photographing part and the photographing angle of the photographing part. Thus, even when the position of the face of the driver is excessively changed, the face of the driver can be rapidly caught by the photographing part. 
     According to the aspect (4), even when the position of the face of the driver is excessively changed, the face of the driver can be caught by the photographing part. Further, a dead angle range of the photographing part is reduced, so that it is rarely necessary to inform of an alarm that a photographing operation cannot be made. Accordingly, since the driver does not need to constantly care about a seated position, a comfortableness of the driver in the vehicle is not harmed. 
     Further, it is judged whether or not the face of the driver is included in a photographed image to adjust at least one of a position of a steering wheel, a photographing position of the photographing part and a photographing angle of the photographing part so as to include a face of the driver in the photographed image. Accordingly, even when the position of the face of the driver is excessively changed, the face of the driver can be efficiently and self-consciously caught. 
     According to the aspect (5), photographed images of two times in the past are compared with each other to detect a displacement of the face of the driver and adjust at least one of the position of the steering wheel, the photographing position of the photographing part and the photographing angle of the photographing part. Thus, even when the position of the face of the driver is excessively changed, the face of the driver can be rapidly caught by the photographing part. 
     According to one or more embodiments, even when the position of the face of the driver is excessively changed, the face of the driver can be caught by the photographing part. Accordingly, the photographing device mounted on the vehicle and the photographing method in the vehicle of the present invention can be applied to a driving support system which monitors a driving state such as the sleepiness, the fatigue and the looking-away driving of the driver who is driving the vehicle to prevent an erroneous start of the vehicle due to, for instance, a mistake in a driving operation. Especially, in the vehicle on which an automatic driving function is mounted, the photographing device mounted on the vehicle and the photographing method in the vehicle of the present invention are most suitably applied before and after the hand over in which a state that a degree of relation of the driver to the automatic driving is low shifts to a state that a degree of relation of the driver thereto is high. 
     The present invention is briefly described above. Further, when a mode for carrying out the invention which will be described below is read by referring to the attached drawings, a detail of the present invention will be more clarified. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view showing a driver in a vehicle on which a photographing device mounted on a vehicle according to an exemplary embodiment of the present invention is mounted and main components in front of the driver, which are seen from a left side. 
         FIG. 2  is a front view showing the vicinity of a meter unit arranged in an instrument panel in front of a driver&#39;s seat shown in  FIG. 1 , which is seen from a direction of the visual point of the driver. 
         FIG. 3  is a schematic view showing a structure example of a wheel position adjusting mechanism of a steering wheel. 
         FIG. 4  is a schematic view showing a structure example of a photographing position adjusting mechanism of a camera. 
         FIG. 5  is a block diagram showing a structure example of a hardware structure of the photographing device mounted on the vehicle according to the exemplary embodiment of the present invention. 
         FIG. 6  is a functional block diagram showing functions realized by the photographing device mounted on the vehicle shown in  FIG. 5 . 
         FIG. 7  is a flowchart showing processes carried out by the photographing device mounted on the vehicle shown in  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     Specific exemplary embodiments of the present invention will be described below by referring to the drawings. 
     Photographing Device Mounted on Vehicle and Summary of Automatic Driving 
     Before a specific explanation is made, initially, the summary of a photographing device mounted on a vehicle of the present invention and an automatic driving technique will be described below. 
     The photographing device mounted on the vehicle photographs a driver by a camera (a photographing part) to detect a driving state such as a behavior or an operation of the driver who drives the vehicle. Then, the photographing device mounted on the vehicle is a device as a base to monitor the driver in a real time based on a photographed image, raise an alarm when an abnormality occurs or automatically record the obtained photographed image. 
     For instance, the photographing device mounted on the vehicle is used to detect a sleepiness or fatigue of the driver, detect a looking-away driving based on the line of vision of the driver and prevent an unintentional erroneous start of the vehicle by an erroneous operation during a driving. 
     Further, functions such as the above-described real time monitor, the abnormality alarm and the automatic record can be realized by combining various kinds of known techniques or existing devices with the device of the present invention. For instance, when the photographing device mounted on the vehicle is connected to a drive recorder or a digital tachograph, various kinds of information obtained during the driving of the vehicle can be automatically recorded. Further, when a safety manager of a transportation company or a taxi company analyzes a recorded result of the drive recorder after the driving is finished, the safety manager can guide a safety driving respectively to the crew who gets on the vehicle as the driver. 
     Further, in recent years, in order to control an automatic driving of the vehicle, a study or development progresses in preparation for an electronic control unit (ECU) of the vehicle in which functions meeting the automatic driving of a level 2 (LV2) or a level 3 (LV3) of an automation level prescribed by, for instance, the Japanese government or US Ministry of Transport Road Traffic Safety Bureau (NHTSA) are mounted on the vehicle. 
     In the level 2, a system automatically carries out a plurality of operations of acceleration, a steering and a brake of the vehicle. However, in the level 2, the driver constantly needs to monitor a driving state and carry out a driving operation as required. 
     On the other hand, in the level 3, since the system carries out all the controls of the acceleration, the steering and the brake of the vehicle, the driver may ordinarily merely monitor the state of the driving. Further, ordinarily, the driver does not necessarily need to monitor the driving state. 
     However, even in the level 3, when the system makes a request at the time of emergency or limitation of the system, the driver needs to respond to this request. Namely, a responsibility for driving needs to be handed over (H/O) to a manual operation of the driver from the system and to shift the level 3 to the level 2 an automation rate of which is lower than that of the level 3. Further, even in the same level, during the automatic driving of the vehicle, an occasion may possibly occur that a traffic line of the vehicle begins to be changed by starting a winker operation, in which the driver is obliged to accompany a hand to a steering wheel and make a monitoring operation. That is, such an occasion may exist that a traveling state in which an assistance of the driver such as an admission of the driver to a decision of the system is not necessary shifts to a traveling state in which any of assistances is necessary. Namely, even in the vehicle on which the automatic driving technique is mounted, an occasion may possibly arise during the driving that a first state in which a driving control is automatically carried out shifts to a second state in which a degree of relation of the driver to the driving control is higher than that of the first state. 
     As described above, with such kind of photographing device mounted on the vehicle, even in the vehicle on which the automatic driving technique is mounted, it is decisively important to constantly catch the face of the driver and photograph the face. However, the usual photographing device mounted on the vehicle may not possibly meet an occasion that the driver relaxes, for instance, during a completely automatic driving in the level 3 and the position of the face is excessively changed. Namely, in the usual photographing device mounted on the vehicle, the face of the driver may possibly deviate from a photographing range of the camera depending on the position of the camera or the opening part of the steering wheel, so that the face of the driver may not be possibly photographed. 
     The photographing device mounted on the vehicle according to the present invention has a special structure as in the below-described exemplary embodiment to assuredly photograph the face of the driver. 
     Main Components of Photographing Device Mounted on Vehicle and Arrangement Thereof 
     By referring to  FIG. 1  and  FIG. 2 , main components of a photographing device  10  mounted on a vehicle of a present exemplary embodiment and an arrangement of them will be described below.  FIG. 1  is a side view showing drivers D 1  and D 2  in the vehicle on which the photographing device  10  mounted on the vehicle according to the exemplary embodiment of the present invention is mounted and the main components in front of the drivers, which are seen from a left side.  FIG. 2  is a front view showing the vicinity of a meter unit  81  arranged in an instrument panel  80  in front of a driver&#39;s seat shown in  FIG. 1 , which is seen from directions of the visual points of the drivers D 1  and D 2 . 
     In images of two persons shown by dotted lines in  FIG. 1 , the driver D 1  shows an ordinary position of the face during a driving. The driver D 2  shows a position of the face when the driver relaxes during the automatic driving (for instance, the level 3) so that the face is located extremely downward. At the time of an actual riding, one driver is seated in the vehicle. 
     As shown in  FIG. 1  and  FIG. 2 , in front of the drivers D 1  and D 2  seated in the driver&#39; s seat of the vehicle, a steering wheel  60  and the instrument panel  80  are arranged. 
     As shown in  FIG. 2 , the steering wheel  60  has a substantially annular ring part  61 , a boss part  62  arranged in a central part of the ring part  61  and connected to a tubular column part  65  so as to freely rotate and two pairs of spoke parts  63  and  64  which diametrically connect the ring part  61  to the boss part  62 . Further, the two pairs of spoke parts  63  and  64  include one pair of upper spoke parts  63  extended and arranged in a transverse direction in an upper side of the vehicle and one pair of lower spoke parts  64  extended and arranged in a transverse direction in a lower side of the vehicle. Further, through an opening part  66  defined by the ring part  61 , the boss part  62  and the one pair of spoke parts  63  and  63 , a below-described camera (a photographing part)  20  of the photographing device  10  mounted on the vehicle catches the faces of the drivers D 1  and D 2  and photographs the faces (see  FIG. 1 ). 
     The instrument panel  80  has the meter unit  81 . The meter unit  81  includes various kinds of meters or display parts such as a speed meter  83 , an engine revolution counter  84 , a direction indicating and display part (not shown in the drawing) on its meter panel  82 . 
     As shown in  FIG. 1  and  FIG. 2 , in an upper part and a side part of the meter panel  82 , a substantially arc shaped meter hood  85  is provided to extend rearward of the vehicle. The meter hood  85  covers the upper part and the side part of the meter panel  82  to prevent external lights such as solar lights from being directly incident on the meter panel  82 . By preventing the incidence, the visibility of the drivers D 1  and D 2  to the meters or the display parts is ensured. 
     Further, the instrument panel  80  has a camera attaching part  86  inside of a substantially central position of the meter hood  85 . The camera attaching part  86  is provided to protrude downward of the vehicle from the meter hood  85 . 
     The camera  20  is arranged in the vehicle. The camera  20  is embedded in the camera attaching part  86  of the meter hood  85  to photograph the drivers D 1  and D 2 . 
     Here, as shown in  FIG. 1 , since an outer upper end part of the boss part  62  of the steering wheel  60  forms an obstacle between the camera  20  and the driver D 2  having a position of the face lowered, so that the camera  20  has a dead angle area. Namely, in the position of the opening part  66  of the steering wheel  60 , a photographing position of the camera  20  and a photographing angle of the camera  20  shown in  FIG. 1 , the face of the driver D 1  can be photographed by the camera  20 , however, the face of the driver D 2  cannot be photographed. Accordingly, as described below, the photographing device  10  mounted on the vehicle of the present exemplary embodiment operates a wheel position adjusting mechanism  70  which mechanically adjusts the position of the steering wheel  60  and a photographing position adjusting mechanism (a photographing position adjusting part) which adjusts the photographing position and the photographing angle of the camera  20 . Thus, even when a seated position of the driver D 2  becomes loose and the position of the face is excessively changed during the automatic driving, the position of the steering wheel  60 , the photographing position of the camera  20  and the photographing angle of the camera  20  are adjusted based on the change to catch the face of the driver D 2 . 
     Structure of Wheel Position Adjusting Mechanism 
       FIG. 3  is a schematic view showing a structure example of a wheel position adjusting mechanism  70  of the steering wheel  60  shown in  FIG. 1 . As shown in  FIG. 3 , the wheel position adjusting mechanism  70  of the steering wheel  60  serves to adjust a vertical (tilt) direction of the steering wheel  60  in the vehicle, and includes a substantially cylindrical housing  72  which supports a steering shaft  71  so as to be freely swung on a swing pivot P relative to a vehicle body B of the vehicle and a straight moving mechanism  73  connected to the housing  72  and the vehicle body B so as to be freely swung. 
     The wheel position adjusting mechanism  70  is ordinarily used to adjust the position of the steering wheel  60  to obtain a maneuverability of steering based on the physical build of the drivers D 1  and D 2 . The wheel position adjusting mechanism is provided as a standard for the first purpose of improvement of the maneuverability of steering depending on vehicles. Accordingly, in the present exemplary embodiment, when the wheel position adjusting mechanism  70  is mounted on the vehicle as a standard, an existing mechanism thereof is commonly used. 
     In the steering shaft  71 , the steering wheel  60  is concentrically attached to a rear end part thereof. To a front end part thereof, a steering mechanism not shown in the drawing is connected. The steering wheel  60  is operated by the drivers D 1  and D 2 , so that steering wheels are steered and rotated through the steering mechanism. 
     The straight moving mechanism  73  includes a wheel position adjusting motor M 3  which is driven to rotate in accordance with a command of a below-described control circuit  40  of the photographing device  10  mounted on the vehicle, a screw shaft  74  driven to rotate by the wheel position adjusting motor M 3 , a nut member  75  which is engaged with the screw shaft  74  and moves straight in an axial direction so as to meet the rotating and driving operation of the screw shaft  74  and a pair of link members  76  firmly fixed to the wheel position adjusting motor M 3  and the nut member  75  and supported so as to be freely swung relative to the housing  72  and the vehicle body B. Further, to the wheel position adjusting motor M 3 , a below-described second motor driving circuit C 2  is electrically connected, and a driving electric power is supplied to the wheel position adjusting motor M 3  by the second motor driving circuit C 2  so as to be driven and rotate. 
     The wheel position adjusting mechanism  70  of the steering wheel  60  is constructed in such away as described above. Thus, when the wheel position adjusting motor M 3  of the straight moving mechanism  73  rotates and drives, the screw shaft  74  rotates in accordance with the rotating and driving operation, and the nut member  75  moves straight. In accordance with the straight movement, the straight moving mechanism  73  expands and contracts to swing the steering shaft  71  on the swing pivot P. As a result, the position of the steering wheel  60  is adjusted. Namely, when the wheel position adjusting motor M 3  is controlled, the position of the steering wheel  60  is adjusted. 
     In  FIG. 3 , in order to explain a basic principle of the wheel position adjusting mechanism  70 , a specific structure thereof is simplified, however, various kinds of specific mechanisms or structures may be suitably used. For instance, the wheel position adjusting motor M 3  may be arranged in a lower side of the housing  72  or the link members  76  may be articulated. 
     Structure of Position Adjusting Mechanism of Camera 
       FIG. 4  is a schematic view showing a structure example of the photographing position adjusting mechanism  30  of the camera  20 . As shown in  FIG. 4 , the photographing position adjusting mechanism  30  includes a housing  31  which holds a casing of the camera  20 , a worm gear mechanism  32  which changes a photographing angle of the camera  20  and a rack and pinion mechanism  35  which moves the housing  31  upward and downward. In the present exemplary embodiment, the casing of the camera  20  is formed substantially in a cubic shape. 
     The housing  31  is formed substantially in a box shape and the casing of the camera  20  is accommodated therein. Further, a rear wall part of the housing  31  is opened. Since the rear part of the camera  20  is opened, the camera  20  can photograph the rear part, namely, the drivers D 1  and D 2 . 
     The worm gear mechanism  32  includes a worm wheel  33  supported on a bottom wall part of the housing  31  so as to freely rotate and fixed to the casing of the camera  20  and a cylindrical worm  34  engaging with the worm wheel  33  and having a rotation shaft supported on the housing  31  so as to freely rotate along a vertical direction. Further, the cylindrical worm  34  is connected to a driving shaft of a below-described first photographing position adjusting motor M 1  (a photographing position adjusting part) at one end part of the rotation shaft. 
     The rack and pinion mechanism  35  includes a rack  36  fixed to a front wall part of the housing  31  in such a way that a longitudinal direction extends along a vertical direction and a pinion  37  engaging with the rack  36  and supported on the camera attaching part  86  of the meter hood  85  so as to freely rotate. Further, the pinion  37  is connected to a driving shaft of a below-described second photographing position adjusting motor (a photographing position adjusting part) M 2  at one end part of its rotation shaft. 
     Since the photographing position adjusting mechanism  30  of the camera  20  is formed in such a way as described above, when the first photographing position adjusting motor M 1  is driven to rotate, the cylindrical worm  34  rotates in accordance with the rotating and driving operation to rotate the worm wheel  33 . At this time, since the worm wheel  33  is fixed to the casing of the camera  20 , the casing of the camera  20  also rotates in accordance with the rotation of the worm wheel  33 . As a result, the photographing angle of the camera  20  is adjusted. 
     On the other hand, when the second photographing position adjusting motor M 2  is driven to rotate, the pinion  37  rotates in accordance with the rotating and driving operation to move straight the rack  36 . At this time, since the rack  36  is fixed to the housing  31  which holds the casing of the camera  20 , the casing of the camera  20  is also moved upward and downward in accordance with the straight movement of the rack  36 . As a result, the photographing position of the camera  20  is adjusted. 
     In  FIG. 4 , in order to explain a basic principle of the photographing position adjusting mechanism  30  like in  FIG. 3 , a specific structure thereof is simplified, however, various kinds of specific mechanisms or structures may be suitably used. 
     Hardware Structure of Photographing Device Mounted on Vehicle 
       FIG. 5  is a block diagram showing a structure example of a hardware structure of the photographing device  10  mounted on the vehicle according to the exemplary embodiment of the present invention. As shown in  FIG. 5 , the photographing device  10  mounted on the vehicle includes the camera  20  which photographs the faces of the drivers D 1  and D 2 , the first and second photographing position adjusting motors M 1  and M 2  which adjust the photographing position and the photographing angle of the camera  20 , a first motor driving circuit (a photographing position adjusting part) C 1  which drives and controls the first and second photographing position adjusting motors M 1  and M 2  and a control circuit  40  which controls the camera  20 , the first motor driving circuit C 1 , the second motor driving circuit C 2  and a device main body. 
     The camera  20  is formed with, for instance, a CCD camera for infrared rays, and has a light receiving element formed with a CCD element and not shown in the drawing and a light source provided integrally with a camera main body and not shown in the drawing which applies prescribed irradiation lights such as the infrared rays toward the drivers D 1  and D 2 . The light receiving part of the camera  20  receives the irradiation lights of the light source reflected on the surfaces of the drivers D 1  and D 2  through a lens. The camera  20  converts the received light to an electric signal and outputs the electric signal to the control circuit  40 . 
     The first and second photographing position adjusting motors M 1  and M 2  are formed with, for instance, stepping motors to drive the worm gear mechanism  32  and the rack and pinion mechanism  35  of the above-described photographing position adjusting mechanism  30 . The first photographing position adjusting motor M 1  drives and rotates the cylindrical worm  34  of the worm gear mechanism  32  to adjust the photographing angle of the camera  20  in a tilt direction (see  FIG. 4 ). Further, the second photographing position adjusting motor M 2  rotates and drives the pinion  37  of the rack and pinion mechanism  35  to adjust the photographing position of the camera upward and downward. 
     The first motor driving circuit C 1  is a driving circuit for the stepping motor and formed with a motor controlling electronic circuit (for instance, a transistor) and electrically connected to the first and second photographing position adjusting motors M 1  and M 2 . The first motor driving circuit C 1  receives a control signal outputted by a below-described photographing position adjusting part  54  to supply a driving electric power to the first and second photographing position adjusting motors M 1  and M 2 . By the supply of the electric power, the first and second photographing position adjusting motors M 1  and M 2  are driven to rotate to desired target values. 
     The control circuit  40  is formed with a general purpose computer and includes a CPU (a central processing unit)  50 , a ROM (a read-only memory circuit), a RAM (a writable memory circuit)  44 , an interface circuit  47 , a communication circuit  48  and a bus  49  which connects mutually these circuits. 
     Further, to the control circuit  40 , the second motor driving circuit C 2  which drives and controls the wheel position adjusting motor M 3  is electrically connected through the interface circuit  47 . The second motor driving circuit C 2  is formed with a motor controlling electronic circuit like the first motor driving circuit C 1  and receives a control signal outputted by a below-described wheel position adjusting part  55  to supply a driving electric power to the wheel position adjusting motor M 3 . 
     In the present exemplary embodiment, since the second motor driving circuit C 2  is formed as a part of the existing wheel position adjusting mechanism  70 , the second motor driving circuit C 2  is formed as a separate structure from the photographing device  10  mounted on the vehicle. 
     The CPU  50  suitably executes or reads programs or data stored in the ROM  41  and the RAM  44  to control the camera  20 , the first motor driving circuit C 1 , the second motor driving circuit C 2  and the device main body. 
     The ROM  41  includes a program storage area  42  and a data storage area  43 . In the program storage area  42 , various kinds of programs (described below) which realize functions of the photographing device  10  mounted on the vehicle are stored. In the data storage area  43 , a plurality of templates is stored which extract features of an image to the photographed image of the camera  20 . The plurality of templates includes a face extracting template which extracts the faces of the drivers D 1  and D 2 . Further, in the data storage area  43 , driving range data showing limits of driving ranges of the first and second photographing position adjusting motors M 1  and M 2  is also stored. 
     The RAM  44  includes a temporary storage area  45  which temporarily stores data formed intermediately when the CPU  50  executes the programs and an image storage area  46  which stores and holds the images photographed by the camera  20  one after another. 
     The interface circuit  47  has a physical interface function to various kinds of external devices provided inside and outside of the vehicle. In the present exemplary embodiment, the interface circuit  47  is connected to the camera  20  and the first and second motor driving circuits C 1  and C 2  so as to communicate mutually with the circuits such as the CPU  50 , the ROM  41  and the RAM  44  through the electric signals. 
     The communication circuit  48  has an interface function as a communication protocol to a LAN in the vehicle so as to output the photographed images or detected results of the photographing device  10  mounted on the vehicle to an upstream device such as an ECU (Electric Control Unit) or an upstream function. 
     Function of Photographing Device Mounted on Vehicle 
       FIG. 6  is a functional block diagram showing functions realized by the photographing device  10  mounted on the vehicle shown in  FIG. 5 . In  FIG. 6 , the functions of the photographing device  10  mounted on the vehicle are represented by “parts” and these “parts” are respectively stored as the programs in the program storage area  42  of the ROM  41  of control circuit  40 . When the CPU  50  of the control circuit  40  properly executes these programs, the functions of the photographing device  10  mounted on the vehicle are respectively realized. 
     The CPU  50  includes, as the functions of the photographing device  10  mounted on the vehicle, an image generating part  51 , an image judging part  52 , a position adjusting control part  53 , a photographing position adjusting part  54  and a wheel position adjusting part  55 . 
     The image generating part  51  fetches an electric signal outputted from the camera  20  to the control circuit  40  through the interface circuit  47 . Further, the image generating part  51  digitally converts the electric signal to apply an image process. Specifically, the image generating part  51  subtracts color of the photographed image of the camera  20 , and then, divides the photographed image into partial areas in which features are equal. After the division of the areas, the image generating part  51  extracts the area occupied by a prescribed object to form a photographed image. After that, the image generating part  51  outputs the photographed image to the image judging part  52  and the image storage area  46  of the RAM  44 . As described above, the RAM  44  stores and holds in the image storage area  46  the photographed images one after another. 
     The image judging part  52  reads the face extracting template stored in the data storage area  43  of the ROM  41  to extract the feature of the image in accordance with a template matching method. Thus, the image judging part  52  judges whether or not the faces of the drivers D 1  and D 2  are included in the photographed image. Then, the image judging part  52  outputs the judged result to the position adjusting control part  53 . 
     When the image judging part  52  judges that the faces of the drivers D 1  and D 2  are included in the photographed image, the image judging part  52  judges that the photographed image of the image generating part  51  can be outputted to the upstream device such as the ECU or the upstream function. As the upstream function, for instance, a function (a program) maybe exemplified which detects the fatigue, sleepiness or the looking-away driving of the drivers D 1  and D 2 . 
     The position adjusting control part  53  reads the photographed image stored and held in the image storage area  46  of the RAM  44  and the driving range data stored in the data storage area  43  of the ROM  41 . Then, the position adjusting control part  53  generates the target values of the first and second position adjusting motors M 1  and M 2  or the wheel position adjusting motor M 3  so as to include the faces of the drivers in the photographed image based on the judged result of the image judging part in order to calculate controlled variables by the wheel position adjusting part  55  and the photographing position adjusting part  54 . 
     Here, when the target values are generated, the position adjusting control part  53  refers to the photographed image stored and held in the image storage area  46  to compare the present photographed image with the past photographed image, detect a displacement of the faces of the drivers D 1  and D 2  and generate the target values of the first and second photographing position adjusting motors M 1  and M 2  or the wheel position adjusting motor M 3  based on the displacement. Specifically, the position adjusting control part  53  judges whether or not the faces of the drivers D 1  and D 2  in the present photographed image are located at positions higher than a position of the photographed image of a previous time (past) to generate the target values. 
     Further, the position adjusting control part  53  refers to the driving range data stored in the data storage area  43  to judge whether or not the driving ranges of the first and second photographing position adjusting motors M 1  and M 2  are located in their limits. When the position adjusting control part  53  judges that the driving ranges are located in the limits of the driving ranges, the position adjusting control part  53  does not generate the target values of the first and second photographing position adjusting motors M 1  and M 2 , but generates the target value of the steel position adjusting motor M 3 . On the other hand, when the position adjusting control part  53  judges that the driving ranges are not located in the limits, the position adjusting control part  53  generates the target values of the first and second photographing position adjusting motors M 1  and M 2 . Namely, in the present exemplary embodiment, the adjustments of the photographing position and the photographing angle of the camera  20  are primarily set. The position adjusting control part  53  outputs the target values generated in such a way as described above to the photographing position adjusting part  54  or the wheel position adjusting part  55 . 
     The photographing position adjusting part  54  calculates the controlled variables of the first and second photographing position adjusting motors M 1  and M 2  based on the target values of the position adjusting control part  53  and outputs the controlled variables to the first motor driving circuit C 1  as the control signals. As described above, the first motor driving circuit C 1  receives the control signals to supply the driving electric power to the first and second photographing position adjusting motors M 1  and M 2 . Thus, the photographing position and the photographing angle of the camera  20  are adjusted and the camera  20  catches the faces of the drivers D 1  and D 2 . 
     The wheel position adjusting part  55  calculates the controlled variable of the wheel position adjusting motor M 3  based on the target value of the position adjusting control part  53  and outputs the controlled variable to the second motor driving circuit C 2  as the control signal. The second motor driving circuit C 2  receives the control signal to supply the driving electric power to the wheel position adjusting motor M 3 . Thus, the position of the steering wheel  60  is adjusted, so that the camera  20  catches the face of the driver through the opening part  66  of the steering wheel  60 . 
     The CPU  50  constructed in such a way as described above adjusts the position of the steering wheel  60  or the photographing position or the photographing angle of the camera  20  based on the positions of the drivers D 1  and D 2  during the driving of the vehicle. Accordingly, even when the drivers D 1  and D 2  relax, for instance, during the automatic driving in the level  3 , and their seated positions are loose and the positions of the faces are excessively changed, the camera  20  can catch the faces of the drivers D 1  and D 2 . 
     Operation of Photographing Device Mounted on Vehicle and Photographing Method in Vehicle 
     By referring to  FIG. 7 , an operation of the photographing device  10  mounted on the vehicle according to the present exemplary embodiment and a procedure of a photographing method in a vehicle will be described below.  FIG. 7  is a flowchart showing processes carried out by the photographing device  10  shown in  FIG. 5 . 
     As shown in  FIG. 7 , in step S 1 , the camera  20  photographs the faces of the drivers D 1  and D 2 . The image generating part  51  fetches to the control circuit  40  the electric signal outputted from the camera  20  through the interface circuit  47 . The image generating part  51  digitally converts the electric signal and applies an image process to generate the photographed image. 
     The image judging part  52  extracts the feature of the image from the photographed image of the image generating part  51  formed in the step S 1  to judge whether or not the faces of the drivers D 1  and D 2  are included in the photographed image (S 2 ). When the image judging part  52  judges that the faces of the drivers D 1  and D 2  are included in the photographed image, an operation flow returns to the step S 1 . On the other hand, when the image judging part  52  judges that the faces of the drivers D 1  and D 2  are not included in the photographed image, an operation flow advances to next step S 3 . 
     In the step S 3 , the position adjusting control part  53  compares the photographed image of the last time with the photographed image of the last time but one to judge whether the face of the driver is located in an upper side or a lower side relative to the position of the present photographed image, that is, an initial direction. The present invention is not limited to a comparison of the photographed image of the last time with the photographed image of the last time but one, and the initial direction may be determined based on a comparison of the photographed images of two times in the past. 
     Further, the position adjusting control part  53  refers to the driving range data stored in the data storage area  43  of the ROM  41  to judge whether or not the driving range of the wheel position adjusting motor M 3  reaches its limit (S 4 ). When the position adjusting control part  53  judges that the driving range of the wheel position adjusting motor M 3  reaches its limit, the position adjusting control part  53  judges the face of the driver is located in an opposite direction to the initial direction determined in the step S 3  (S 5 ). When the position adjusting control part  53  judges that the driving range does not reach its limit, the determined direction is set to the initial direction as it is. 
     Then, the position adjusting control part  53  judges whether or not the determined direction is higher than a direction of the last time (the past) (S 6 ). When the determined direction is a direction higher than the direction of the last time (the past), the operation flow advances to S 10 . When the determined direction is a direction lower than the direction of the last time, the operation flow advances to S 7 . 
     Further, the position adjusting control part  53  refers to the driving range data stored in the data storage area  43  of the ROM  41  to judge whether or not the driving ranges of the first and second photographing position adjusting motors M 1  and M 2  reach their limits (S 7 ). When the position adjusting control part  53  judges that the driving ranges of the first and second photographing position adjusting motors M 1  and M 2  reach their limits, the operation flow advances step S 8 . On the other hand, when the position adjusting control part  53  judges that the driving ranges of the first and second photographing position adjusting motors M 1  and M 2  do not reach their limits, the operation flow advances to step S 9 . 
     In the step S 8 , the wheel position adjusting part  55  calculates the controlled variable of the wheel position adjusting motor M 3  so as to lower the position of the steering wheel  60  based on the target value of the position adjusting control part  53 . Then, the wheel position adjusting part  55  outputs the controlled variable to the second motor driving circuit C 2  as the control signal. 
     In the step S 9 , the photographing position adjusting part  54  calculates the controlled variables of the first and second photographing position adjusting motors M 1  and M 2  so as to raise the photographing position of the camera  20  and lower the photographing angle thereof based on the target values of the position adjusting control part  53 . Then, the photographing position adjusting part  54  outputs the controlled variables to the first motor driving circuit C 1  as the control signals. 
     When the operation flow moves to the step S 10 , the same process as that of the step S 7  is carried out. Then, when the position adjusting control part  53  judges that the driving ranges of the photographing position adjusting motors M 1  and M 2  reach their limits, the operation flow moves to step S 11 . On the other hand, when the position adjusting control part  53  judges that the first and second photographing position adjusting motors M 1  and M 2  do not reach their limits, the operation flow moves to step S 12 . 
     In the step S 11 , the same process as that of the step S 8  is carried out. The wheel position adjusting part  55  calculates the controlled variable of the wheel position adjusting motor M 3  so as to raise the position of the steering wheel  60  based on the target value of the position adjusting control part  53 . 
     In the step S 12 , the same process as that of the process of the step S 9  is carried out. The photographing position adjusting part  54  calculates the controlled variables of the first and second photographing position adjusting motors M 1  and M 2  so as to lower the photographing position of the camera  20  and raise the photographing angle thereof based on the target values of the position adjusting control part  53 . 
     Since the CPU  50  of the control circuit  40  carries out a series of the above-described steps S 1  to S 12 , even when the drivers D 1  and D 2  relax during an automatic driving in the level  3 , the seated positions are loose and the positions of the faces are excessively changed, the camera can constantly catch the faces of the drivers D 1  and D 2 . 
     Advantages of the Present Exemplary Embodiment 
     As described above, the photographing device  10  mounted on the vehicle according to the present exemplary embodiment includes the wheel position adjusting part  55  which adjusts the position of the steering wheel  60  mounted on the vehicle, the photographing position adjusting part  54  which adjusts the photographing position and the photographing angle of the camera  20 , the photographing position adjusting mechanism  30 , the first and second photographing position adjusting motors M 1  and M 2  and the first motor driving circuit C 1  and the position adjusting control part  53  which controls the wheel position adjusting part  55  and the photographing position adjusting part  54  based on the photographed result of the camera  20 . Accordingly, even when the positions of the faces of the drivers D 1  and D 2  are excessively changed, the faces of the drivers D 1  and D 2  can be caught by the camera  20 . Further, a dead angle range of the camera  20  is reduced, so that such a necessity can be suppressed as to inform of an alarm of abnormality that a photographing operation cannot be made. Accordingly, since the drivers D 1  and D 2  do not need to constantly care about seated positions, a comfortableness of the drivers D 1  and D 2  in the vehicle is not harmed. 
     The photographing device  10  mounted on the vehicle according to the present exemplary embodiment further includes the image judging part  52  which judges whether or not the faces of the drivers D 1  and D 2  are included in the photographed image based on the photographed image of the image generating part  51 . The position adjusting control part  53  controls the wheel position adjusting part  55  and the photographing position adjusting part  54  so as to include the faces of the drivers in the photographed image based on the judged result of the image judging part  52 . Thus, even when the positions of the faces of the drivers D 1  and D 2  are excessively changed, the faces of the drivers D 1  and D 2  can be efficiently and self-consciously caught. 
     According to the photographing device  10  mounted on the vehicle, the position adjusting control part  53  compares the photographed images of the two times in the past with each other to detect the displacement of the faces of the drivers D 1  and D 2  and adjust at least one of the wheel position adjusting part  55  and the photographing position adjusting part  54  based on the displacement. Thus, even when the positions of the faces of the drivers D 1  and D 2  are excessively changed, the faces of the drivers D 1  and D 2  can be rapidly caught by the camera  20 . 
     Further, according to the photographing method in the vehicle of the present exemplary embodiment, even when the positions of the faces of the drivers D 1  and D 2  are excessively changed, the faces of the drivers D 1  and D 2  can be caught by the camera  20 . Further, a dead angle range of the camera  20  is reduced, so that it is rarely necessary to inform of an alarm of abnormality that a photographing operation cannot be made. Accordingly, since the drivers D 1  and D 2  do not need to constantly care about seated positions, a comfortableness of the drivers D 1  and D 2  in the vehicle is not harmed. Further, since it is judged whether or not the faces of the drivers D 1  and D 2  are included in the photographed image and the position of the steering wheel  60  and the photographing position of the camera  20  and the photographing angle of the camera  20  are adjusted so as to include the faces of the drivers D 1  and D 2  in the photographed image, even when the positions of the faces of the drivers D 1  and D 2  are excessively changed, the faces of the drivers D 1  and D 2  can be efficiently and self-consciously caught. 
     Further, according to the photographing method in the vehicle of the present exemplary embodiment, the photographed images of the two times in the past are compared with each other to detect a change of the faces of the drivers D 1  and D 2  and adjust the position of the steering wheel  60 , the photographing position of the camera  20  and the photographing angle of the camera  20  based on the change. Thus, even when the positions of the faces of the drivers D 1  and D 2  are excessively changed, the faces of the drivers D 1  and D 2  can be rapidly caught by the camera  20 . 
     The present invention is not limited to the above-described exemplary embodiments and may be suitably modified and improved. In addition thereto, materials, forms, dimensions, numbers, arranged positions or the like of the components in the above-described exemplary embodiments are respectively arbitrary and are not limited as long as the present invention can be achieved. 
     In the above-described exemplary embodiment, for instance, the image generating part  51  is provided as a part of the structure of the control circuit  40 , the present invention is not limited thereto. The image generating part may be formed as a part of the structure of the camera (the photographing part)  20  or as a separate image generating device. 
     Further, in the above-described exemplary embodiment, the second motor driving circuit C 2  and the wheel position adjusting motor M 3  are formed as separate structures from the photographing device  10  mounted on the vehicle, however, the present invention is not limited thereto. They may be formed as a part of the photographing device  10  mounted on the vehicle. 
     Further, in the above-described exemplary embodiment, one camera  20  is provided, however, the resent invention is not limited thereto. A plurality of cameras may be provided. Further, in the above-described exemplary embodiment, the light source is provided integrally with the camera  20 , however, the present invention is not limited thereto. The light source may be provided as a separate member. 
     Further, the “part” in the present invention or the present exemplary embodiment is not limited merely to a physical structure realized by hardware and includes a structure that a function of the structure is realized by software such as programs. Further, a function of one structure may be realized by two or more physical structures, or functions of two or more structures may be realized by, for instance, one physical structure. 
     Here, features of the above-described exemplary embodiments of the photographing device mounted on the vehicle and the photographing method in the vehicle according to the present invention are respectively briefly summarized and described in below-described [1] to [5]. 
     [1] A photographing device ( 10 ) mounted on a vehicle comprising: 
     a photographing part (a camera  20 ) which is mounted on the vehicle to photograph a face of a driver (D 1 , D 2 ); 
     a wheel position adjusting part ( 55 ) which adjusts a position of a steering wheel ( 60 ) mounted on the vehicle; 
     a photographing position adjusting part (a photographing position adjusting part  54 , a photographing position adjusting mechanism  30 , a first photographing position adjusting motor M 1 , a second photographing position adjusting motor M 2 , a first motor driving circuit C 1 ) which adjusts at least one of a photographing position of the photographing part (the camera  20 ) and a photographing angle of the photographing part (the camera  20 ); and 
     a position adjusting control part ( 53 ) which controls at least one of the wheel position adjusting part ( 55 ) and the photographing position adjusting part (the photographing position adjusting part  54 , the photographing position adjusting mechanism  30 , the first photographing position adjusting motor M 1 , the second photographing position adjusting motor M 2 , the first motor driving circuit C 1 ) based on a photographed result of the photographing part (the camera  20 ). 
     [2] The photographing device ( 10 ) mounted on the vehicle according to the above-described [1], further comprising: 
     an image generating part ( 51 ) which generates a photographed image based on the photographed result of the photographing part (the camera  20 ); and 
     an image judging part ( 52 ) which judges whether or not the face of the driver (D 1 , D 2 ) is included in the photographed image based on the photographed image of the image generating part ( 51 ), 
     wherein the position adjusting control part ( 53 ) controls at least one of the wheel position adjusting part ( 55 ) and the photographing position adjusting part (the photographing position adjusting part  54 , the photographing position adjusting mechanism  30 , the first photographing position adjusting motor M 1 , the second photographing position adjusting motor M 2 , the first motor driving circuit C 1 ) so as to include the face of the driver (D 1 , D 2 ) in the photographed image based on the judged result of the image judging part ( 52 ). 
     [3] The photographing device ( 10 ) mounted on the vehicle according to the above-described [2], 
     wherein the position adjusting control part ( 53 ) compares the photographed image at present with the photographed image in a past to detect a displacement of the face of the driver (D 1 , D 2 ) and control at least one of the wheel position adjusting part ( 55 ) and the photographing position adjusting part (the photographing position adjusting part  54 , the photographing position adjusting mechanism  30 , the first photographing position adjusting motor M 1 , the second photographing position adjusting motor M 2 , the first motor driving circuit C 1 ) based on the displacement. 
     [4] A photographing method in a vehicle comprising: 
     photographing a face of a driver (D 1 , D 2 ) in a photographing part (a camera  20 ) mounted on the vehicle, 
     generating a photographed image based on a photographed result in the photographing (S 1 ), 
     judging whether or not the face of the driver (D 1 , D 2 ) is included in the photographed image (S 2 ), and 
     adjusting at least one of a position of a steering wheel ( 60 ) mounted on the vehicle, a photographing position of the photographing part (the camera  20 ), and a photographing angle of the photographing part (the camera  20 ) (S 3  to S 12 ) so as to include the face of the driver (D 1 , D 2 ) in the photographed image based on a judged result in the judging (S 2 ). 
     [5] The photographing method in the vehicle according to the above-described [4], 
     wherein the adjusting includes comparing the photographed images of two times in a past with each other to detect a displacement of the face of the driver (D 1 , D 2 ) and adjusting at least one of the position of the steering wheel ( 60 ), the photographing position of the photographing part (the camera  20 ), and the photographing angle of the photographing part (the camera  20 ) based on the displacement. 
     DESCRIPTION OF REFERENCE NUMERALS AND SIGNS 
       10  . . . photographing device mounted on vehicle  20  . . . camera (photographing part)  30  . . . photographing position adjusting mechanism (photographing position adjusting part)  31  . . . housing  32  . . . worm gear mechanism  33  . . . worm wheel  34  . . . cylindrical worm  35  . . . rack and pinion mechanism  36  . . . rack  37  . . . pinion  40  . . . control circuit  41  . . . ROM  42  . . . program storage area  43  . . . data storage area  44 _RAM  45  . . . temporary storage area  46  . . . image storage area  47  . . . interface circuit  48  . . . communication circuit  49  . . . bus  50  . . . CPU  51  . . . image generating part  52  . . . image judging part  53  . . . position adjusting control part  54  . . . photographing position adjusting part  55  . . . wheel position adjusting part  60  . . . steering wheel  61  . . . ring part  62  . . . boss part  63  . . . upper spoke part  64  . . . lower spoke part  65  . . . column part  66  . . . opening part  70  . . . wheel position adjusting mechanism  71  . . . steering shaft  72  . . . housing  73  . . . straight moving mechanism  74  . . . screw shaft  75  . . . nut member  76  . . . link member  80  . . . instrument panel  81  . . . meter unit  82  . . . meter panel  83  . . . speed meter  84  . . . engine revolution counter  85  . . . meter hood  86  . . . camera attaching part D 1 , D 2  . . . driver B . . . vehicle body P . . . swing pivot M 1  . . . first photographing position adjusting motor (photographing position adjusting part) M 2  . . . second photographing position adjusting motor (photographing position adjusting part) M 3  . . . wheel position adjusting motor C 1  . . . first motor driving circuit (photographing position adjusting part) C 2  . . . second motor driving circuit