Patent Publication Number: US-11643057-B2

Title: Vehicle traveling control apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/629,778, filed on Jun. 22, 2017, which claims priority from Japanese Patent Application No. 2016-125183, filed on Jun. 24, 2016, the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a vehicle traveling control apparatus which decreases a vehicle speed of a vehicle to stop the vehicle when a driver of the vehicle has fallen into an abnormal state in which the driver loses an ability to drive the vehicle. 
     BACKGROUND ART 
     An apparatus has conventionally been proposed which determines whether or not a driver has fallen into an abnormal state where the driver loses an ability to drive a vehicle (for example, a drowsy driving state, a mental and physical failure state, and the like), and decelerates the vehicle when the driver is determined to be in such an abnormal state (for example, refer to Japanese Patent Application Laid-Open (kokai) No. 2009-73462.). 
     It should be noted that hereinafter an “abnormal state where a driver loses an ability to drive a vehicle” is simply also referred to as an “abnormal state” and a “determination whether or not a driver is in the abnormal state” is simply also referred to as an “abnormality determination of a driver”. 
     SUMMARY OF THE INVENTION 
     When the driver has fallen into the abnormal state, a rescue request for an emergency facility can be made by using a help network system. In the help network system, a help net center is established where a rescue request is received from a site of an abnormality occurrence, and by reporting to (calling in) the help net center, local emergency facilities are called for service. For example, the help net center acquires a positional information of the vehicle transmitted from a communication device of the vehicle inside which the driver in the abnormal state is. Then, the help net center makes a call for an ambulance as well as a call for a rescue team to head to the vehicle position, and requests a road management station to take care of other vehicles for the stopped vehicle (display messages on electronic message boards and set up traveling restriction signs, and so on, and hereinafter refer to “support other vehicles”), and so on. 
     When the driver has fallen into the abnormal state, it is desired to rescue the driver by reporting to the help net center as soon as possible. Besides, when a vehicle traveling control apparatus decelerates or stops the vehicle by detecting that the driver is in the abnormal state, it is desired to report to the road management station as soon as possible. 
     However, if the vehicle is made to stop under a situation where a communication connection between the communication device of the vehicle and the help net center cannot be established, the help net center cannot recognize the position of the vehicle inside which the driver is, and therefore it is considered that it is impossible to properly make the call for an ambulance as well as the call for a rescue team and to request a road management station for supporting other vehicles. 
     The present invention is made in order to resolve the problem above. That is, one of objects of the present invention is to provide a vehicle traveling control apparatus of a vehicle with which an emergency measure such as a rescue of a driver can be properly taken, using a help network system. 
     In order to achieve the object above, one feature of a vehicle traveling control apparatus of the present invention lies in that the vehicle traveling control apparatus applied to a vehicle comprises;
         abnormality determination means ( 10 , S 13 , S 62 , S 104 , S 109 ) for continuously determining whether or not a driver of the vehicle is in an abnormal state where the driver loses an ability to drive the vehicle;   vehicle position acquisition means ( 10 ,  100 ,  101 ) for acquiring a positional information representing a current position of the vehicle;   stop traveling means ( 10 ,  30 ,  40 , S 39 , S 113 ) for making the vehicle stop by decreasing a vehicle speed of the vehicle to zero after an abnormality determination point in time which is a point in time at which the driver has been determined to be in the abnormal state; and   report means ( 10 ,  110 ,  111 , S 37 ) for transmitting to a help net center where a rescue request is arranged the positional information of the vehicle via wireless communication based on a determination result that the driver is in the abnormal state,   wherein,   the stop traveling means is configured to;
           determine (S 34 ) whether or not the report means is in a state of a communication connection to the help net center; and   make the vehicle stop (S 34 : Yes, S 39 ) under a condition that the report means is in the state of a communication connection.   
               

     In the present invention, the abnormality determination means continuously conducts the determination whether or not the driver of the vehicle is in the abnormal state in which the driver loses the ability to drive the vehicle. As described later, the abnormality determination of the driver can be conducted by means of various methods. For example, the abnormality determination can be conducted by determining whether or not a state in which the driver does not conduct any operation to drive the vehicle (a state-with-no-driving-operation) continues for more than or equal to a threshold time (a threshold time for the abnormality determination of the driver), or by determining whether or not a state in which the driver does not push a confirmation button even when the driver is urged to push the confirmation button continues for more than or equal to a threshold time, and so on. Alternatively, the abnormality determination can be conducted by using a so called “driver monitor technique” disclosed in Japanese Patent Application Laid-Open (kokai) No. 2013-152700 and so on. 
     The vehicle position acquisition means acquires the positional information representing a current position of the vehicle. The stop traveling means makes the vehicle stop by decreasing the vehicle speed of the vehicle to zero after the abnormality determination point in time which is a point in time at which the driver has been determined to be in the abnormal state. Besides, the report means transmits to the help net center where the rescue request is arranged the positional information of the vehicle via wireless communication based on the determination result that the driver is in the abnormal state. “Transmitting the positional information of the vehicle to the help net center” means reporting to the help net center that the driver is in the abnormal state. Therefore, hereinafter, “transmitting the positional information of the vehicle to the help net center” is referred to as “reporting”. 
     With this configuration, a call for an ambulance to head to the vehicle position and a request to a road management station for supporting other vehicles and the like can be made at an early timing. 
     However, if the vehicle is made to stop under a situation where the communication connection between the report means and the help net center cannot be established, the help net center cannot recognize the position of the vehicle inside which the driver is, and therefore it becomes impossible to request for an emergency measure such as a rescue of the driver. 
     Therefore, the stop traveling means of the present invention determines whether or not the report means is in the state of the communication connection to the help net center, and makes the vehicle stop under the condition that the report means is in the state of the communication connection. Accordingly, it is possible to make the vehicle stop under a situation where the help net center recognizes the position of the vehicle inside which the driver who has been determined to be in the abnormal state is. As a result, according to the present invention, the emergency measure such as the rescue of the driver and the like can be taken properly. 
     One feature of another aspect of the present invention lies in that;
         the stop traveling means is configured to;
           start decelerating the vehicle (S 113 ) from a temporary abnormality determination point in time (S 108 ) which is a timing at which the driver has been first determined to be in the abnormal state by the abnormality determination means; and   make the vehicle stop (S 39 ) under a condition where the report means is in the state of a communication connection in a situation where an accuracy of the determination by the abnormality determination means has exceeded an accuracy of a determination at the temporary abnormality determination point in time (S 112 : Yes, S 116 : Yes), and   
               

     the report means is configured to start transmitting the positional information of the vehicle in the situation where an accuracy of the determination by the abnormality determination means has exceeded an accuracy of a determination at the temporary abnormality determination point in time (S 118 , S 31 : Yes). 
     According to another aspect of the present invention, the deceleration of the vehicle is started from the temporary abnormality determination point in time which is the timing at which the driver has been first determined to be in the abnormal state. At this stage, the positional information of the vehicle is not transmitted to the help net center yet. When the accuracy of the determination by the abnormality determination means has exceeded the accuracy of the determination at the temporary abnormality determination point in time, the report means starts transmitting the positional information of the vehicle. For example, when a determination that the driver is in the abnormal state has continued to be made for a predetermined set time from the temporary abnormality determination point in time, or when a vehicle speed has decreased to a predetermined set vehicle speed greater than zero in a situation where the determination that the driver is in the abnormal state continues to be made, and the like, it can be said that the situation where the accuracy of the determination by the abnormality determination means has exceeded the accuracy of the determination at the temporary abnormality determination point in time is realized. 
     For example, if the driver has not actually fallen into the abnormal state, it becomes possible to make the driver become aware of the deceleration of the vehicle to induce the driver to conduct an accelerating operation and the like. If there is such a response from the driver, the determination that the driver is in the abnormal state can be cancelled. Accordingly, erroneous reports to the help net center (that is, reporting to the help net center in spite of that the driver is not actually in the abnormal state) can be reduced. 
     On the other hand, the report means starts transmitting the positional information of the vehicle in the situation where the accuracy of the determination by the abnormality determination means has exceeded the accuracy of the determination at the temporary abnormality determination point in time after the deceleration of the vehicle was started. Besides, the stop traveling means makes the vehicle stop (decelerates the vehicle until the vehicle speed becomes zero) under the condition that the report means is in the state of the communication connection. Therefore, it is possible to make the vehicle stop under a situation where the help net center recognizes the position of the vehicle inside which the driver who has been determined to be in the abnormal state is. Accordingly, the emergency measure such as the rescue of the driver and the like can be taken properly. 
     One feature of another aspect of the present invention lies in that; 
     the stop traveling means is configured to stop decelerating the vehicle (S 42 : No, S 43 , S 35 ) when a communication between the report means and the help net center is interrupted in midst of deceleration for making the vehicle stop. 
     For example, owing to the vehicle entering a tunnel and the like, there may be a case that the communication between the report means and the help net center is interrupted in midst of the deceleration for making the vehicle stop. If the vehicle is made to stop in such a case, it becomes impossible for the help net center to recognize the position of the vehicle inside which the driver who has been determined to be in the abnormal state is. 
     Therefore, in another aspect of the present invention, in a case when the communication between the report means and the help net center is interrupted in midst of the deceleration for making the vehicle stop, that is, in midst of the deceleration of the vehicle for decreasing the vehicle speed of the vehicle to zero, the stop traveling means stops decelerating the vehicle not to make the vehicle stop. For example, the stop traveling means makes the vehicle travel at a constant speed. Accordingly, it is possible to move the vehicle to a position where the communication between the report means and the help net center can be resumed. Therefore, the communication between the report means and the help net center is ensured to be made at a position where the vehicle stops, and as a result, the emergency measure such as the rescue of the driver and the like can be taken properly. 
     One feature of another aspect of the present invention lies in that; 
     the stop traveling means is configured not to make the vehicle stop (S 47 : Yes, S 36 ) until a stop permission signal is transmitted from the help net center. 
     In another aspect of the present invention, the stop traveling means does not make the vehicle stop until the stop permission signal is transmitted from the help net center. For example, the stop traveling means makes the vehicle travel at a constant speed until the stop traveling means receives the stop permission signal transmitted from the help net center. Therefore, it is possible to make the vehicle stop under a more appropriate situation. 
     One feature of another aspect of the present invention lies in that; 
     the stop traveling means is configured to make the vehicle stop (S 52 : Yes, S 53 ) when a state in which a communication connection between the report means and the help net center cannot be established has continued for more than an upper limit time set in advance. 
     For example, in a case when a communication failure and the like of the help network system occurred, the state in which the communication connection between the report means and the help net center cannot be established continues all long. Therefore, the stop traveling means makes the vehicle stop when a time during which the communication connection between the report means and the help net center cannot be established has exceeded the upper limit time set in advance. Accordingly, it is possible to cope with the aforementioned failure occurrence. 
     In the above description, references used in the following descriptions regarding embodiments are added with parentheses to the elements of the present invention, in order to assist in understanding the present invention. However, those references should not be used to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic configuration diagram of a vehicle traveling control apparatus according to an embodiment of the present invention. 
         FIG.  2    is a schematic configuration diagram of a help network system. 
         FIG.  3    is a flowchart showing a routine under a normal state. 
         FIG.  4    is a flowchart showing a routine under an abnormal state. 
         FIG.  5    is a flowchart showing a modification example 1 of the routine under the abnormal state. 
         FIG.  6    is a flowchart showing a modification example 2 of the routine under the abnormal state. 
         FIG.  7    is a flowchart showing a modification example 3 of the routine under the abnormal state. 
         FIG.  8    is a flowchart showing a modification example 4 of the routine under the abnormal state. 
         FIG.  9    is a flowchart showing a modification example 1 of the routine under the normal state. 
     
    
    
     DESCRIPTION OF THE EMBODIMENT 
     A vehicle traveling control apparatus (driving support apparatus) according to an embodiment of the present invention will be described below, referring to figures. 
     A vehicle traveling control apparatus according to the embodiment of the present invention is, as shown in  FIG.  1   , applied to a vehicle (hereinafter, may be referred to as an “own vehicle” in order to distinguish it from other vehicles), and comprises a driving support ECU  10 , an engine ECU  30 , a brake ECU  40 , an electrically-driven parking brake ECU  50 , a steering ECU  60 , a meter ECU  70 , a warning ECU  80 , a body ECU  90 , a navigation ECU  100 , and an external communication ECU  110 . 
     Each of the ECUs is an electric control unit comprising a microcomputer as a main part. Those ECUs are connected via CAN (Controller Area Network) which is not illustrated so that the ECUs are capable of mutually transmitting and receiving information. In the present specification, the microcomputer includes CPU, ROM, RAM, a non-volatile memory, an interface I/F, or the like. The CPU is configured to realize/perform various functions by executing instructions (i.e., programs or routines) stored in the ROM. Some of those ECUs or all of those ECUs may be integrated into one ECU. 
     The driving support ECU  10  is connected to sensors (including switches) listed below, and is configured to receive a detection signal or an output signal of these sensors. It should be noted that each sensor may be connected to ECUs other than the driving support ECU  10 . In this case, the driving support ECU  10  receives the detection signal or the output signal of the sensor via CAN from the ECU to which the sensor is connected. 
     An accelerator pedal operation amount sensor  11  is configured to detect an operation amount (an accelerator position) of an accelerator pedal  11   a  of the own vehicle, and to output a signal representing the accelerator pedal operation amount AP. 
     A brake pedal operation amount sensor  12  is configured to detect an operation amount of a brake pedal  12   a  of the own vehicle, and to output a signal representing the brake pedal operation amount BP. 
     A stop lamp switch  13  is configured to output a low level signal when the brake pedal  12   a  is not being depressed (is not being operated), and to output a high level signal when the brake pedal  12   a  is being depressed (is being operated). 
     A steering angle sensor  14  is configured to detect a steering angle of the own vehicle, and to output a signal representing the steering angle θ. 
     A steering torque sensor  15  is configured to detect a steering torque added to a steering shaft US of the own vehicle by an operation of a steering wheel SW, and to output a signal representing the steering torque Tra. 
     A vehicle speed sensor  16  is configured to detect a traveling speed (a vehicle speed) of the own vehicle, and to output a signal representing the vehicle speed SPD. 
     A radar sensor  17   a  is configured to obtain information regarding a road ahead of the own vehicle, and a three-dimensional object present in the road. The three-dimensional object includes, for example, moving objects such as a pedestrian, a bicycle and an automobile, and static objects such as a power pole, a tree, and a guardrail. Hereinafter, these three-dimensional objects may be referred to as a “target object.” 
     The radar sensor  17   a  comprises a “radar transmission/reception part and a signal processor”, both of which are not illustrated. 
     The radar transmission/reception part emits an electric wave in a millimeter waveband (hereinafter, referred to as a “millimeter wave”) to an ambient region of the own vehicle including a front region of the own vehicle, and receives a millimeter wave (i.e., a reflected wave) reflected from a target object which is present in the emitted area. 
     The signal processor obtains, every predetermined period of time, an inter-vehicle distance (a longitudinal distance), a relative speed, a lateral distance, a relative lateral speed, and the like, with respect to each detected target object based on a phase difference between the transmitted millimeter wave and the received reflected wave, an attenuation level of the reflected wave, a time from a point in time of transmitting the millimeter wave to a point in time of receiving the reflected wave, or the like. 
     A camera apparatus  17   b  comprises a “stereo camera and an image processor”, both of which are not illustrated. 
     The stereo camera photographs/captures landscapes of a left-side region and a right-side region in front of the vehicle to obtain a left-and-right pair of image data. 
     The image processor is configured to calculate information as to whether or not a target object is present, a relative relationship between the own vehicle and the target object and the like, based on the left-and-right pair of image data photographed/captured by the stereo camera to output them. 
     It should be noted that the driving support ECU  10  is configured to determine a relative relationship (target object information) between the own vehicle and the target object by composing the relative relationship between the own vehicle and the target object obtained by the radar sensor  17   a  and the relative relationship between the own vehicle and the target object obtained by the camera apparatus  17   b . Further, the driving support ECU  10  is configured to recognize a lane marker such as a left white line and a right white line of a road (hereinafter, simply referred to as a “white line”) based on the left-and-right pair of image data (road image data) photographed/captured by the camera apparatus  17   b  and to obtain a shape of the road (a curvature radius representing a degree of how much the road is curved), a positional relationship between the road and the vehicle, and the like. In addition, the driving support ECU  10  is configured to also obtain the information whether or not a road side wall exists based on the image data photographed/captured by the camera apparatus  17   b.    
     An operation switch  18  is a switch to be operated by a driver. The driver can select whether or not to perform a traffic lane keeping control (LKA: Lane Keeping Assist control) by operating the operation switch  18 . Moreover, the driver can select whether or not to perform a trailing inter-vehicle distance control (ACC: Adaptive Cruise Control) by operating the operation switch  18 . 
     A yaw rate sensor  19  is configured to detect a yaw rate of the own vehicle to output an actual yaw rate YRa. 
     A confirmation button  20  is arranged at a position capable of being operated by the driver. The confirmation button  20  is configured to output a low-level signal when not being operated and to output a high-level signal when being pressed. 
     The driving support ECU  10  is configured to perform the LKA and the ACC. Further, as described later, the driving support ECU  10  is configured to determine whether or not the driver is in an abnormal state in which the driver loses an ability to drive the vehicle, and to perform various types of control to perform appropriate processes when the driver is determined to be in the abnormal state. 
     The engine ECU  30  is connected to an engine actuator  31 . The engine actuator  31  includes actuators for changing a driving state of an internal combustion engine  32 . In the present embodiment, the internal combustion engine  32  is a gasoline fuel injection, spark ignition, multi-cylinder engine, and comprises a throttle valve to adjust an intake air amount. The engine actuator  31  includes at least a throttle valve actuator to change an opening degree of the throttle valve. The engine ECU  30  can change torque which the internal combustion engine  32  generates by driving the engine actuator  31 . The torque which the internal combustion engine  32  generates is transmitted to a non-illustrated driving wheels via a non-illustrated transmission gear. Therefore, the engine ECU  30  can control the engine actuator  31  to control a driving force of the own vehicle, so as to change an acceleration state (an acceleration rate). 
     The brake ECU  40  is connected to a brake actuator  41 . The brake actuator  41  is provided in a hydraulic circuit between a non-illustrated master cylinder to compress operating fluid with a depression force of the brake pedal and friction brake mechanisms  42  provided at left-and-right-front wheels and left-and-right-rear wheels. Each of the friction brake mechanisms  42  comprises a brake disc  42   a  fixed to the wheel and a brake caliper  42   b  fixed to a vehicle body. The brake actuator  41  adjusts, in response to an instruction from the brake ECT  40 , a hydraulic pressure that is supplied to a wheel cylinder which is built in the brake caliper  42 , and operates the wheel cylinder with the hydraulic pressure. Thereby, the brake actuator  41  presses a brake pad onto the brake disc  42   a  to generate a friction braking force. Accordingly, the brake ECU  40  can control the braking force of the own vehicle by controlling the brake actuator  41 . 
     The electrically-driven parking brake ECU (hereinafter, may be referred to as an “EPB ECU”)  50  is connected to a parking brake actuator (hereinafter, may be referred to as a “PKB actuator”)  51 . The PKB actuator  51  is an actuator for pressing the brake pad onto the brake disc  42   a  or for, in a case when comprising a drum brake, pressing a shoe onto a drum rotating with the wheel. Therefore, EPB ECU  50  can add a parking brake force to the wheel by means of the PKB actuator  51  to maintain the vehicle in a stop state. 
     The steering ECU  60  is a control apparatus of a well-known electrically-driven power steering system and is connected to a motor driver  61 . The motor driver  61  is connected to a steering motor  62 . The steering motor  62  is incorporated into a non-illustrated “steering mechanism including the steering wheel, the steering shaft coupled to the steering wheel, a gear mechanism for steering, and the like” of the vehicle. The steering motor  62  generates torque with electric power supplied from the motor driver  61  to be able to add a steering assist torque using the torque, or to turn left-and-right steered wheels. 
     The meter ECU  70  is connected to a non-illustrated digital indication type meter and is also connected to a hazard lamp  71  and a stop lamp  72 . The meter ECU  70  can, in response to an instruction from the driving support ECU  10 , make the hazard lamp  71  blink and make the stop lamp  72  light. 
     The warning ECU  80  is connected to a buzzer  81  and an indicator  82 . The warning ECU  80  can, in response to an instruction from the driving support ECU  10 , make the buzzer  81  sound to alert the driver, make a mark for alerting (for example, a warning lamp) light on the indicator  82 , display a warning message on the indicator  82 , and display an operating state of a driving support control on the indicator  82 . 
     The body ECU  90  is connected to a door lock device  91  and a horn  92 . The body ECU  90  can unlock the door lock device  91  in response to an instruction from the driving support ECU  10 . In addition, the body ECU  90  can make the horn  92  sound in response to an instruction from the driving support ECU  10 . 
     The navigation ECU  100  is connected to a GPS receiver  101 , a map database  102 , a touch-screen display  103 , and so on. The GPS receiver  101  receives a GPS signal for detecting a current position of the own vehicle. The map database  102  stores map information etc. The touch-screen display  103  is a human machine interface. The navigation ECU  100  identifies the current position of the own vehicle based on the GPS signal, and performs various types of processing based on the own vehicle position and on the map information etc. stored in the map database  102  to perform a route guidance using the display  103 . 
     The map information stored in the map database  102  includes road information. The road information includes parameters representing a shape of a road for every section (for example, a curvature radius or a curvature of a road representing a degree of curve of the road). It should be noted that the curvature is a reciprocal of the curvature radius. 
     The external communication ECU  110  is connected to a wireless communication device  111 . The external communication ECU  110  and the wireless communication device  111  are wireless communication terminals for connecting to a help network system. As shown in  FIG.  2   , the help network system HNS is configured by including a communication network CN, and a help net center HNC connected to the communication network CN, and a fire station FS, a police station CS and a road management station RS, each of which is connected to the communication network CN (hereinafter, these may also be referred to as an “on-site processing department”.), and a wireless relay base station RA connected to the communication network CN, and user communication terminals UT which the user of this system possesses. One of the user communication terminals UT corresponds to the external communication ECU  110  (including the wireless communication device  111 ). It should be noted that the help net center HNC, the fire station FS, the police station CS and the road management station RS, each of which is connected to the communication network CN means a communication device provided at each of those institutions. 
     Upon reception of a help net connection instruction from the driving support ECU  10 , the external communication ECU  110  actuates the wireless communication device  111  to perform a communication connection to the help net center HNC. The help net center HNC comprises a communication device for transmitting/receiving signals to/from unspecified large number of user communication terminals UT. In the present specification, “communicating with the help net center” means communicating with the communication device provided at the help net center HNC. 
     In addition, the external communication ECU  110  comprises a microphone and a speaker for a telephone call with an operator at the help net center HNC, and is also configured to report on-site information to the operator from an inside of the own vehicle. Further, the external communication ECU  110  comprises a call button as well for calling the help net center HNC. It should be noted that in the present embodiment, processing under the following situation will be described, that is, the situation where the driver is in the abnormal state in which the driver cannot perform driving operations, namely, the driver cannot make a telephone call with the operator using these functions. 
     Upon reception of the help net connection instruction from the driving support ECU  10 , the external communication ECU  110  obtains from the navigation ECU  100  the current position of the own vehicle detected with the GPS receiver  21 , and transmits to the help net center HNC a signal (hereinafter, may be referred to as a “help signal”) including a vehicle position information representing the current position and an ID number which identifies the own vehicle (for example, a vehicle number). As will be described later, the driving support ECU  10  continuously performs a determination whether or not the driver is in the abnormal state in which the driver loses the ability to drive the vehicle while the vehicle is traveling. The driving support ECU  10  transmits the help net connection instruction to the external communication ECU  110  when the driver has been determined to be in the abnormal state. The external communication ECU  110  transmits the help signal to the help net center HNC using the wireless communication device  111  based on this help net connection instruction. 
     Upon reception of the help signal, the help net center HNC searches for an on-site processing department in charge of an area where the vehicle which has transmitted the help signal is positioned, and transmits various types of information to the searched on-site processing department. The on-site processing department dispatches emergency vehicles such as an ambulance, a police vehicle and so on to the site based on the various types of information transmitted from the help net center HNC, and then rescues the driver, carries the driver to a hospital as well as supports other vehicles (displays messages on electronic message boards and sets up traveling restriction signs, and so on). 
     &lt;Summary of Control Processing&gt; 
     Next, summary of the control processing performed by the driving support ECU  10  will be described. The driving support ECU  10  repeatedly determines whether or not “the driver is in the abnormal state in which the driver loses the ability to drive the vehicle (may be simply referred to as an “abnormal state”)” while the vehicle is traveling. 
     When the driving support ECU  10  has detected that the driver is in the abnormal state, the driving support ECU  10  transmits a communication connection request to the help net center HNC. The driving support ECU  10  does not start decelerating the vehicle until the communication connection to the help net center HNC is established. When the communication connection to the help net center HNC is established, the driving support ECU  10  starts transmitting the help signal to the help net center HNC. On the other hand, the help signal cannot be transmitted to the help net center HNC until the communication connection to the help net center HNC is established. During that time (that is, while the communication connection to the help net center HNC is not established), the driving support ECU  10  does not start the deceleration of the vehicle, but makes the vehicle travel at a constant speed so that a vehicle speed at that point in time (a point in time at which the abnormal state has been detected) is maintained. 
     The traveling control of the vehicle stated above is conducted when the driver&#39;s abnormality is detected under a situation where a trailing inter-vehicle distance control (ACC) is being conducted. When the trailing inter-vehicle distance control is being conducted, the vehicle travels without an accelerator pedal operation by the driver. Therefore, in a case when the driver&#39;s abnormality is being detected, a deceleration control which makes a vehicle decelerate at a predetermined target deceleration or a constant speed control which maintains a vehicle speed are conducted in place of the trailing inter-vehicle distance control. In this case, when the driver&#39;s abnormality is detected, it is preferable that the driving support ECU  10  starts the traffic lane keeping control (LKA) if the traffic lane keeping control (LKA) has not been conducted. 
     Now, the traffic lane keeping control and the trailing inter-vehicle distance control will be described first. 
     &lt;Traffic Lane Keeping Control (LKA)&gt; 
     The traffic lane keeping control (hereinafter, referred to as “LKA”) is a control to support a steering operation of the driver by adding the steering torque to the steering mechanism so that a position of the own vehicle is kept nearby (in the vicinity of) a target traveling line in a “lane on which the own vehicle is traveling (a traveling lane)”. The LKA itself is well known (for example, refer to Japanese Patent Applications Laid-Open (kokai) No. 2008-195402, No. 2009-190464, No. 2010-6279, and Japanese Patent No. 4349210, and so on.). Therefore, a simple description will next be made below. 
     The driving support ECU  10  performs the LKA when the LKA is being requested by the operation of the operation switch  18 . The driving support ECU  10  recognizes (obtains) “the left white line LL and the right white line LR” of the lane on which the own vehicle is traveling based on the image data transmitted from the camera apparatus  17   b  when the LKA is being requested, and determines a central position of a pair of these white lines to be a target traveling line Ld. In addition, the driving support ECU  10  calculates a curve radius (a curvature radius) R of the target traveling line Ld, and a position and a direction of the own vehicle in a traveling line defined by the left white line LL and the right white line LR. 
     Then, the driving support ECU  10  calculates a distance Dc (hereinafter, referred to as a “center distance Dc”) in a width direction of a road between a central position of a front end of the own vehicle and the target traveling line Ld, and a deviation angle θy (hereinafter, referred to as a “yaw angle θy”) between a direction of the target traveling line Ld and the traveling direction of the own vehicle. 
     Further, the driving support ECU  10  calculates a target yaw rate YRc* using the following formula (1) based on the center distance Dc, the yaw angle θy, and a road curvature v (=1/curvature radius R) every time a predetermined calculation interval elapses. In the formula (1), K1, K2 and K3 are control gains. The target yaw rate YRc* is a yaw rate set so that the own vehicle can travel along the target traveling line Ld.
 
 YRc*=K 1× Dc+K 2×θ y+K 3× v   (1)
 
     The driving support ECU  10  calculates a target steering torque Tr* for obtaining the target yaw rate YRc* based on the target yaw rate YRc* and the actual yaw rate YRa every time a predetermined calculation interval elapses. More specifically, the driving support ECU  10  stores a lookup table in advance which defines a relationship between a “deviation between the target yaw rate YRc* and the actual yaw rate YRa” and the “target steering torque Tr*”, and calculates the target steering torque Tr* by applying the deviation between the target yaw rate YRc* and the actual yaw rate YRa to the table. Thereafter, the driving support ECU  10  controls the steering motor  62  using the steering ECU  60  so that the actual steering torque Tra matches with (becomes equal to/coincides with) the target steering torque Tr*. It should be noted that the LKA is a control that only assists a steering wheel operation by the driver such that the own vehicle travels along the target traveling line, and the LKA is not a control that permits “driving without holding the steering wheel”. Therefore, the driver is required to hold the steering wheel. The above description is a summary of the LKA. 
     &lt;Trailing Inter-Vehicle Distance Control (ACC)&gt; 
     The trailing inter-vehicle distance control (hereinafter, referred to as “ACC”) is a control to make the own vehicle trail the preceding vehicle traveling right ahead the own vehicle, while keeping the inter-vehicle distance between the preceding vehicle and the own vehicle to be/at a predetermined distance. The ACC itself is well known (for example, refer to Japanese Patent Applications Laid-Open (kokai) No. 2014-148293 and No. 2006-315491, and Japanese Patents No. 4172434, and No. 4929777 and so on.) Therefore, a simple description will be made below. 
     The driving support ECU  10  performs the ACC in a case when the ACC is being requested by the operation of the operation switch  18 . 
     More specifically, the driving support ECU  10  selects a trailing target vehicle (i.e., a trailing objective vehicle) based on the target object information obtained by the radar sensor  17   a  and the camera apparatus  17   b  in a case when the ACC is being requested. For example, the driving support ECU  10  determines whether or not a relative position of the target object (n) identified by the lateral distance Dfy(n) and the inter-vehicle distance Dfx(n) of the detected target object (n) exists (or, is present) in a trailing target vehicle area which is set in advance so as to have a lateral length that becomes smaller as the inter-vehicle distance becomes larger. Thereafter, when the relative position of the target object exists (or, is present) in the trailing target vehicle area for more than or equal to a predetermined time, the driving support ECU  10  selects the target object (n) as the trailing target vehicle. 
     Further, the driving support ECU  10  calculates a target acceleration Gtgt using either a formula (2) or a formula (3) below. In the formula (2) and the formula (3), a Vfx(a) is a relative speed of the trailing target vehicle (a), k1 and k2 are predetermined positive gains (coefficients), and ΔD1 is an inter-vehicle deviation obtained by subtracting a “target inter-vehicle distance Dtgt” from an “inter-vehicle distance Dfx(a) of the trailing target vehicle (a)” (=Dfx(a)−Dtgt). It should be noted that the target inter-vehicle distance Dtgt is calculated by multiplying a target inter-vehicle time Ttgt which is set by the driver by using the operation switch  18  by the vehicle speed SPD of the own vehicle (that is, Dtgt=Ttgt×SPD). 
     The driving support ECU  10  determines the target acceleration Gtgt by using (in accordance with) the following formula (2) in a case when the value (k1×ΔD1+k2×Vfx(a)) is positive or “0”. Ka1 is a positive gain (coefficient) for an acceleration and is set to be a value less than or equal to be “1”. 
     The driving support ECU  10  determines the target acceleration Gtgt by using (in accordance with) the following formula (3) in a case when the value (k1×ΔD1+k2×Vfx(a)) is negative. Kd1 is positive a gain (coefficient) for a deceleration and is set to be “1” in the present embodiment.
 
 Gtgt  (for the acceleration)= ka 1×( k 1×Δ D 1+ k 2× Vfx ( a ))  (2)
 
 Gtgt  (for the deceleration)= kd 1×( k 1×Δ D 1+ k 2× Vfx ( a ))  (3)
 
     It should be noted that in a case when the target object does not exist (or not be present) in the trailing target vehicle area, the driving support ECU  10  determines the target acceleration Gtgt based on a “target speed which is set depending on the target inter-vehicle time Ttgt” and the vehicle speed SPD, in such a manner that the vehicle speed SPD matches with (becomes equal to) the target speed. 
     The driving support ECU  10  controls the engine actuator  31  through the engine ECU  30 , and when needed, controls the brake actuator  41  through the brake ECU  40  in such a manner that the acceleration of the own vehicle matches with the target acceleration Gtgt. The above description is a summary of the ACC. 
     &lt;Specific Control Routine&gt; 
     Next, the traveling control processing performed by the driving support ECU  10  will be described. The driving support ECU  10  performs the traveling control of the vehicle and at the same time, controls a report to the help net center HNC by performing the following routines in parallel, that is, a routine under a normal state shown in  FIG.  3    and a routine under an abnormal state shown in  FIG.  4    every time a predetermined calculation interval elapses. 
     The driving support ECU  10  sets the current driver&#39;s state, classifying the state into “normal” and “abnormal”, and stores the set state. An abnormality flag Fe is used as information showing the driver&#39;s state. The value of the abnormality flag Fe being “1” means that the current state of the driver is “abnormal”. At a point in time when the ignition key is turned on, the abnormality flag Fe is initialized to be set to “0” (Fe=0). 
     When an ignition switch is turned on, the routines in  FIG.  3    and  FIG.  4    start. In this case, since the abnormality flag Fe has been initialized (Fe=0), the routine under the normal state in  FIG.  3    substantially functions. Hereinafter, a description will be made, starting with the routine under the normal state in  FIG.  3   . It should be noted that the routine under the normal state in  FIG.  3    will be activated when the ACC is being performed. 
     When the routine under the normal state is started, the driving support ECU  10  determines, at a step S 11 , whether or not the abnormality flag Fe is “0”. The driving support ECU  10  makes an “Yes” determination since the abnormality flag Fe has been initialized right after the ignition switch was turned on. In this case, the driving support ECU  10  proceeds to a step S 12  to determine whether or not the vehicle speed SPD is more than or equal to an abnormality determination permission vehicle speed SPD 0  set in advance. The driving support ECU  10  tentatively terminates this routine under the normal state in a case when the vehicle speed SPD does not reach the abnormality determination permission vehicle speed SPD 0 . 
     In a case when the vehicle speed SPD is determined to be more than or equal to the abnormality determination permission vehicle speed SPD 0  (S 12 : Yes) as a result of repeating the determination processes stated above, the driving support ECU  10  determines, at a step S 13 , whether or not the driver is in a state where the driver does not perform any driving operation (a state-with-no-driving-operation). The state-with-no-driving-operation is a state where any of parameters consisting of one or more combinations of “the accelerator pedal operation amount AP, the brake pedal operation amount BP, the steering torque Tra, and a signal level of the stop lamp switch  13 ” which vary depending on a driver does not change. In the present embodiment, the driving support ECU  10  regards a state where any of “the accelerator pedal operation amount AP, the brake pedal operation amount BP, and the steering torque Tra” does not change as well as the steering torques remains “0” as the state-with-no-driving-operation. 
     In a case when the current state is not the state-with-no-driving-operation (S 13 : Yes), the driving support ECU  10  clears, at a step S 14 , a value of an abnormality determination timer te to zero and tentatively terminates the routine under the normal state. The value of the abnormality determination timer te is set to “0” when the ignition switch is turned on. 
     When the state-with-no-driving-operation is detected as a result of repeating the processes stated above, the driving support ECU  10  increases, at a step S 15 , the value of the abnormality determination timer te by “1” on all such occasions. Therefore, the value of the abnormality determination timer te represents a time during which the state-with-no-driving-operation continues. 
     Next, the driving support ECU  10  determines, at a step S 16 , whether or not the value of the abnormality determination timer te is more than or equal to an abnormality confirmation time teref set in advance. When the duration time of the state-with-no-driving-operation is less than the abnormality confirmation time teref, the driving support ECU  10  tentatively terminates the routine under the normal state. 
     When an operation by the driver is detected (S 13 : Yes) in the middle of the repetition of the processes stated above, the value of the abnormality determination timer te is cleared to zero at the step S 14 . 
     On the other hand, when the value of the abnormality determination timer te reaches the abnormality confirmation time teref without any driving operations by the driver being detected (S 16 : Yes), the driving support ECU  10  determines that the driver is in the abnormal state where the driver loses the ability to driver the vehicle, and proceeds to a step S 17  to set the abnormality flag Fe to “1”. After the abnormality flag Fe was set to “1”, a determination at the step S 11  becomes “No”, and the routine under the abnormal state ( FIG.  4   ) will substantially function in place of the routine under the normal state ( FIG.  3   ). 
     It should be noted that when the abnormality flag Fe is set to “1”, the driving support ECU  10  is preferred to automatically perform the LKA. That is, it is preferable that the driving support ECU  10  forcibly perform the LKA even when the operation switch  18  is not selected to perform the LKA. Accordingly, even when the driver does not perform the steering operation, the own vehicle can be made to travel along the target traveling line (the central position of the left and right white lines). In addition, when the abnormality flag Fe is set to “1”, the driving support ECU  10  stops the ACC, and makes the vehicle decelerate or travel at a constant speed as described later. 
     Besides, when any operation by the driver is not detected, an alert to the driver may be started at an arbitrary timing at which the value of the abnormality determination timer te has not reached the abnormality confirmation time teref. For example, the driving support ECU  10  outputs a no-driving-operation warning instruction to the warning ECU  80  when the value of the abnormality determination timer te exceeds a warning start time tal. Accordingly, the warning ECU  80  makes a warning sound from the buzzer  81 , makes a warning lamp blink on the indicator  82 , and displays a warning message urging the driver to operate any one of “the accelerator pedal  11   a , the brake pedal  12   a , and the steering wheel SW”. 
     Next, the routine under the abnormal state ( FIG.  4   ) performed by the driving support ECU  10  will be described. When the routine under the abnormal state ( FIG.  4   ) is started, the driving support ECU  10  determines, at a step S 31 , whether or not the abnormality flag Fe is “1”. The driving support ECU  10  makes an “Yes” determination right after the abnormality flag Fe was set to “1” in the routine under the normal state, and proceeds to a step S 32 . The driving support ECU  10  determines, at the step S 32 , whether or not a stop permission flag Fa is set to “0”. 
     The stop permission flag Fa is an information showing whether or not the vehicle is in a situation where stopping the vehicle is permitted when the driver is determined to be in the abnormal state. The value of the stop permission flag Fa being “1” means that the vehicle is in the situation where stopping the vehicle is permitted. The stop permission flag Fa being “0” means that the vehicle is in a situation where stopping the vehicle is not permitted. At a point in time when the ignition key is turned on, the stop permission flag Fa is initialized to be set to “0” (Fa=0). Therefore, the driving support ECU  10  makes an “Yes” determination when performing a determination process of the step S 32  for the first time. 
     When the driving support ECU  10  makes an “Yes” determination at the step S 32 , the driving support ECU  10  outputs, at a subsequent step S 33 , the help net connection instruction to the external communication ECU  110 . Accordingly, the external communication ECU  110  transmits the communication connection request to the help net center HNC via the wireless communication device  111 . In this case, the communication connection request may be transmitted to the help net center HNC by transmitting the help signal to the help net center HNC. 
     Next, the driving support ECU  10  determines, at a step S 34 , whether or not the communication connection between the wireless communication device  111  and the help net center HNC (hereinafter, simply referred to as the “communication connection”) is established. When the communication connection is established, the external communication ECU  110  transmits to the driving support ECU  10  a communication result signal representing an establishment of the communication connection. Therefore, the driving support ECU  10  performs the determination of the step S 34  based on whether or not the driving support ECU  10  has received the communication result signal transmitted from the external communication ECU  110 . 
     It should be noted that in this step S 34 , the communication connection is determined to be established when a response to the communication connection request is received from the help net center HNC. However, for example, a determination whether or not a wireless communication environment where the vehicle is currently positioned is not “out of range” (that is, a state of the communication connection) may be performed in the step S 34 . 
     When the communication connection is not established, the driving support ECU  10  keeps, at a step S 35 , the vehicle speed at the current vehicle speed. In this case, the driving support ECU  10  outputs to the engine ECU  30  and the brake ECU  40  an instruction signal for making the own vehicle travel at a constant speed of the current vehicle speed SPD obtained based on the signal from the vehicle speed sensor  16 . Accordingly, a traveling state of the own vehicle becomes a state of traveling at a constant speed. It should be noted that in a case when the traveling at a constant speed is continued, it is preferable that the driving support ECU  10  stores a vehicle speed of when the traveling at a constant speed was started and keeps that vehicle speed. In addition, the process at the step S 35  does not necessarily require that the vehicle speed of the own vehicle is kept at the current vehicle speed. The vehicle may be made to travel at a constant speed set in advance (a safe vehicle speed). The driving support ECU  10  tentatively terminates the routine under the abnormal state after performing the process of the step S 35 . 
     When the communication connection between the wireless communication device  111  and the help net center HNC is established (S 34 : Yes) as a result of repeating the processes stated above, the driving support ECU  10  proceeds to a step S 36 , and sets the stop permission flag Fa to “1” (Fa=1). Subsequently, the driving support ECU  10  outputs, at the step S 37 , a transmission instruction of the help signal to the external communication ECU  110 . Accordingly, the help signal is transmitted to the help net center HNC from the wireless communication device  111 . The help signal is a signal representing that the driver is in the abnormal state where the driver loses the ability to drive the vehicle, and includes the positional information of the own vehicle at the current time and the ID for identifying the own vehicle. It should be noted that the help signal may be information including at least the positional information of the own vehicle. 
     Next, the driving support ECU  10  determines, at a step S 38 , whether or not the own vehicle is not in a stop state based on the vehicle speed SPD. When this determination is made for the first time, the driving support ECU  10  makes an “Yes” determination since the own vehicle is not in the stop state. Based on this determination, the driving support ECU  10  proceeds to a step S 39 , and decelerates the own vehicle at an acceleration-under-the-abnormal-state a which is a target acceleration with a constant value set in advance. In this case, the driving support ECU  10  calculates an acceleration of the own vehicle from a change amount of the vehicle speed SPD per unit time obtained based on the signal from the vehicle speed sensor  16 , and outputs to the engine ECU  30  and the brake ECU  40  an instruction signal for matching the acceleration thereof with the acceleration-under-the-abnormal-state a. 
     Subsequently, the driving support ECU  10  outputs, at a step S 40 , a lighting instruction of the stop lamp  72  and a blinking instruction of the hazard lamp  71  to the meter ECU  70 . As a result, the stop lamp  72  lights and the hazard lamp  71  blinks, making it possible to alert a driver of a following vehicle. The driving support ECU  10  tentatively terminates the routine under the abnormal state after performing the process of the step S 40 . 
     The driving support ECU  10  decelerates the own vehicle, transmitting the help signal to the help net center HNC by repeating the processes described above. Accordingly, the help net center HNC can make an emergency dispatch request to the on-site processing department which is in charge of the area where the own vehicle is positioned. 
     When the vehicle speed SPD reaches zero by the deceleration of the own vehicle, that is, when the own vehicle stops (S 38 : No), the driving support ECU  10  outputs, at a step S 41 , an actuation instruction of the electrically-driven parking brake to the electrically-driven parking brake ECU  50 , the blinking instruction of the hazard lamp  71  to the meter ECU  70 , and an unlock instruction of the door lock device  91  to the body ECU  90 . Accordingly, the electrically-driven parking brake is brought into an actuation state, a blinking state of the hazard lamp  71  is continued, and the door lock device  91  is brought into an unlock state. In addition, the driving support ECU  10  prohibits the acceleration override (invalidate an acceleration request based on the accelerator pedal operation) while the own vehicle is in the stop state. The driving support ECU  10  tentatively terminates the routine under the abnormal state after performing the process of the step S 41 . 
     According to the vehicle traveling control apparatus of the present embodiment described above, when the state-with-no-driving-operation has continued for more than or equal to the abnormality confirmation time teref (S 16 : Yes), the driver is determined to have fallen into the abnormal state, and the communication connection request is transmitted to the help net center HNC. Stopping the vehicle (decelerating the vehicle for making the vehicle stop) is not permitted until it is detected that the communication connection between the wireless communication device  111  and the help net center HNC is established, that is, until it is confirmed that a situation where the help signal can be transmitted to the help net center HNC is realized. Besides, while the communication connection between the wireless communication device  111  and the help net center HNC is not established, the vehicle speed of the own vehicle is maintained even after the driver was determined to have fallen into the abnormal state. That is, it is possible to keep the own vehicle in the traveling state so that the own vehicle does not stop until the communication connection is established. 
     For example, when the driver of the own vehicle has been determined to be in the abnormal state in a tunnel, it is difficult to establish the communication connection between the wireless communication device  111  and the help net center HNC. In this case, it is possible to make the own vehicle travel at a constant speed until a situation where the own vehicle comes out of the tunnel and the aforementioned communication connection is established is realized. 
     As a result, according to the vehicle traveling control apparatus of the present embodiment, since stopping the vehicle (decelerating the vehicle for making the vehicle stop) is permitted under a situation where the help net center HNC can surely recognize the position of the own vehicle, it becomes possible to properly make the call for an ambulance as well as the call for a rescue team and to request a road management station for supporting other vehicles. 
     Modification Example 1 of a Routine Under an Abnormal State 
     For example, in midst of the deceleration for making the vehicle stop, owing to the vehicle entering a tunnel and the like, there may be a case that the communication between the wireless communication device  111  and the help net center HNC is interrupted after the communication connection was once established. If the vehicle is made to stop in such a case, it becomes impossible for the help net center HNC to recognize the position of the vehicle inside which the driver who has been determined to be in the abnormal state is. 
     Therefore, in a modification example 1 of the routine under the abnormal state, in a case when the communication between the wireless communication device  111  and the help net center HNC is interrupted in midst of the deceleration for making the vehicle stop, the driving support ECU  10  stops a decelerated traveling and switches to a traveling at a constant speed (a constant speed traveling). 
       FIG.  5    shows the modification example 1 of the routine under the abnormal state. The driving support ECU  10  repeatedly performs a routine under the abnormal state of the modification example 1 ( FIG.  5   ) instead of the routine under the abnormal state of the embodiment ( FIG.  4   ) every time a predetermined calculation interval elapses. Hereinafter, only a simple description will be made for processes same as the processes of the embodiment by adding the same step numbers to  FIG.  5   . The routine under the abnormal state of the modification example 1 corresponds to the routine under the abnormal state of the embodiment to which processes of a step S 42  and a step S 43  are added. 
     When the communication connection between the wireless communication device  111  and the help net center HNC is established and the stop permission flag Fa is set to “1” (S 36 ) after the routine under the abnormal state of the modification example 1 was started, the driving support ECU  10  proceeds to a step S 42 . The driving support ECU  10  determines, at the step S 42 , whether or not the communication connection between the wireless communication device  111  and the help net center HNC continues. The driving support ECU  10  makes an “Yes” determination right after the stop permission flag Fa was set to “1” at the step S 36 , and in this case, the driving support ECU  10  proceeds to the aforementioned step S 37  (the transmission process of the help signal). 
     On the other hand, when the communication connection between the wireless communication device  111  and the help net center HNC is interrupted, the driving support ECU  10  makes a “No” determination at the step S 42 . In this case, the driving support ECU  10  sets, at the step S 43 , the stop permission flag Fa to “0” (Fa=0), and proceeds to the step S 35  to make the own vehicle travel at a constant speed so that the current vehicle speed is maintained. 
     Therefore, after the stop permission flag Fa was set to “0” at the step S 43 , the communication connection request is to be transmitted again to the help net center HNC by the processes from the step S 33 . When the communication connection is again established (S 34 : Yes) as a result of repeating the processes stated above, the transmission of the help signal to the help net center HNC (S 37 ) and the deceleration of the own vehicle (S 39 ) are started. 
     According to the modification example 1 of the routine under the abnormal state described above, when the communication between the wireless communication device  111  and the help net center HNC is interrupted in midst of the deceleration for making the vehicle stop, the driving support ECU  10  stops the decelerated traveling and switches to the constant speed traveling. Accordingly, it is possible to move the vehicle to a position where the communication between the wireless communication device  111  and the help net center HNC can be resumed. Therefore, the communication between the wireless communication device  111  and the help net center HNC is ensured to be made at a position where the vehicle stops, and as a result, the emergency measure such as the rescue of the driver and the like can be taken properly. 
     Modification Example 2 of the Routine Under the Abnormal State 
     In this modification example 2 of the routine under the abnormal state, a permission condition for making the vehicle stop is that the stop permission signal is transmitted to the own vehicle from the help net center HNC. That is, the driving support ECU  10  does not make the own vehicle stop until the driving support ECU  10  receives the stop permission signal from the help net center HNC even if the communication connection between the wireless communication device  111  and the help net center HNC is established. 
       FIG.  6    shows the modification example 2 of the routine under the abnormal state. The driving support ECU  10  repeatedly performs a routine under the abnormal state of the modification example 2 ( FIG.  6   ) instead of the routine under the abnormal state of the embodiment ( FIG.  4   ) every time a predetermined calculation interval elapses. Hereinafter, only a simple description will be made for processes same as the processes of the embodiment by adding the same step numbers to  FIG.  6   . The routine under the abnormal state of the modification example 2 corresponds to the routine under the abnormal state of the embodiment to which processes of steps S 44 , S 45 , S 46 , and S 47  are added between the step S 32  and the step S 36 . 
     After the routine under the abnormal state of the modification example 2 was started, the driving support ECU  10  makes an “Yes” determination at the step S 31  and the step S 32 , and proceeds to the step S 44 . The driving support ECU  10  determines, at the step S 44 , whether or not a connection flag Fc is set to “0”. 
     The connection flag Fc is an information showing whether or not the communication connection between the wireless communication device  111  and the help net center HNC is established. The value of the connection flag Fc being “1” means that the communication connection is established. The value of the connection flag Fc being “0” means that the communication connection is not established. At a point in time when the ignition key is turned on, the connection flag Fc is initialized to be set to “0” (Fc=0). Therefore, the driving support ECU  10  makes an “Yes” determination when performing a determination process of the step S 44  for the first time. 
     When the connection flag Fc is “0”, the driving support ECU  10  outputs, at the step S 33 , the help net connection instruction to the external communication ECU  110 , and while the communication connection is not established (S 34 : No), keeps the vehicle speed of the own vehicle at the current vehicle speed at the step S 35 . When the communication connection between the wireless communication device  111  and the help net center HNC is established (S 34 : Yes) as a result of repeating the processes stated above, the driving support ECU  10  sets, at the step S 45 , the connection flag Fc to “1”. Subsequently, the driving support ECU  10  outputs, at the step S 46 , the transmission instruction of the help signal to the external communication ECU  110 . Accordingly, the help signal is transmitted to the help net center HNC from the wireless communication device  111 . The help net center HNC makes an emergency dispatch request to the on-site processing department which is in charge of the area where the own vehicle is positioned based on the help signal. 
     Subsequently, the driving support ECU  10  determines, at the step S 47 , whether or not the stop permission signal was transmitted from the help net center HNC. 
     When the road management station RS which is one of the on-site processing departments receives an emergency dispatch request from the help net center HNC, the road management station RS performs a preparation for making the vehicle inside which the driver who has fallen into the abnormal state is (may be referred to as the “vehicle”) stop. This preparation includes, for example, a display of a message of “emergency stop vehicle” using electronic message boards, an activation of a smoke candle, a regulation of traveling lanes for other vehicles with pylons and the like, and so on. When the aforementioned preparation has been finished, the road management station RS transmits a preparation finished signal to the help net center HNC. When the help net center HNC has received the preparation finished signal from the road management station RS, the help net center HNC transmits the stop permission signal to the wireless communication device  111  of the vehicle. 
     When the stop permission signal has not been transmitted from the help net center HNC (that is, when the driving support ECU  10  has not received the stop permission signal) at the step S 47 , the driving support ECU  10  proceeds to the step S 35  and keeps the vehicle speed of the own vehicle at the current vehicle speed. When it is detected that the stop permission signal has been transmitted from the help net center HNC (S 47 : Yes) as a result of repeating the processes stated above, the driving support ECU  10  proceeds to the step S 36 , and sets the stop permission flag Fa to “1”. Accordingly, the deceleration of the own vehicle is started and eventually the own vehicle stops. 
     According to the modification example 2 of the routine under the abnormal state, the deceleration of the own vehicle is not started until the driving support ECU  10  receives the stop permission signal from the help net center HNC, for example, until the road management station RS finishes the preparation after having transmitted the help signal to the help net center HNC. Therefore, it is possible to keep an impact on other vehicles caused by making the own vehicle stop (collision, traffic jam and the like) to a minimum. 
     Modification Example 3 of the Routine Under the Abnormal State 
     In the aforementioned embodiment, when the abnormal state of the driver was detected, the driving support ECU  10  decelerates the own vehicle to make the own vehicle stop at a stage where the communication connection between the wireless communication device  111  and the help net center HNC has been established. However, the following case may be considered that the communication connection is not established for some reason. For example, a case where a communication failure has occurred in the help net system HNS may correspond to such a case. 
     Therefore, in the modification example 3 of the routine under the abnormal state, in a case when the communication connection between the wireless communication device  111  and the help net center HNC cannot be established for more than or equal to a predetermined time in spite of transmitting the communication connection request to the help net center HNC, the driving support ECU  10  stops the constant speed traveling of the own vehicle and makes the own vehicle stop. 
       FIG.  7    shows the modification example 3 of the routine under the abnormal state. A flowchart shown in  FIG.  7    is a partial flowchart showing processes which are added to after the step S 35  in the routine under the abnormal state of the embodiment ( FIG.  4   ). 
     After the driving support ECU  10  makes the own vehicle travel at a constant speed at the step S 35 , the driving support ECU  10  proceeds to a step S 51 , and increases a value of a communication failure timer tc by “1”. The value of this communication failure timer tc has been set to “0” when the ignition switch is turned on. Therefore, the communication failure timer tc represents a time during which the communication connection is not established in spite of transmitting the communication connection request to the help net center HNC, in other words, a time during which stopping the vehicle is not permitted after the driver has been determined to be in the abnormal state. 
     Subsequently, the driving support ECU  10  determines, at a step S 52 , whether or not the value of the communication failure timer tc has exceeded the communication abnormality determination time tcref set in advance. When the value of the communication failure timer tc is less than or equal to the communication abnormality determination time tcref, the driving support ECU  10  tentatively terminates the routine under the abnormal state. The driving support ECU  10  repeats the processes stated above. Therefore, when the value of the communication failure timer tc is less than or equal to the communication abnormality determination time tcref, the own vehicle continues to be made to travel at a constant speed. When any abnormality has not occurred in a communication system, the communication connection between the wireless communication device  111  and the help net center HNC is established before the value of the communication failure timer tc reaches the communication abnormality determination time tcref. Therefore, the processes after the step S 35  will not be performed. 
     On the other hand, when some abnormality has occurred in the communication system, the value of the communication failure timer tc exceeds the communication abnormality determination time tcref (S 52 : Yes). In this case, the driving support ECU  10  sets, at a step S 53 , the stop permission flag Fa to “1”, and tentatively terminates the routine under the abnormal state. Therefore, when the routine under the abnormal state is resumed, the deceleration of the own vehicle is started (the processes progress in the following order, S 32 , S 37 , S 38 , S 39 ). Accordingly, it is possible to make the own vehicle stop. 
     According to the modification example 3 of the routine under the abnormal state described above, when a time during which the communication connection between the wireless communication device  111  and the help net center HNC cannot be established, in other words, a time during which stopping the vehicle is not permitted after the driver has been determined to be in the abnormal state has exceeded the communication abnormality determination time tcref, the own vehicle is decelerated so that the own vehicle stops. Therefore, it is possible to cope with the occurrence of communication failures in the help network system HNS. 
     It should be noted that the modification example 3 of the routine under the abnormal state can be also applied to the modification example 1 or the modification example 2 of the routine under the abnormal state. In this case as well, when the time during which stopping the vehicle is not permitted after the driver has been determined to be in the abnormal state has exceeded the communication abnormality determination time tcref, the own vehicle is decelerated so that the own vehicle stops. 
     Modification Example 4 of the Routine Under the Abnormal State 
     It is considered that the driver&#39;s state comes back to the normal state from the abnormal state after the driving support ECU  10  determined that the driver was in the abnormal state. Therefore, in the modification example 4 of the routine under the abnormal state, processes of when the driver&#39;s state has come back to the normal state are added. 
       FIG.  8    shows the modification example 4 of the routine under the abnormal state. A flowchart shown in  FIG.  8    is a partial flowchart showing processes which are added to between the step S 31  and the step S 32  in the routines under the abnormal state of the embodiment and the modification examples 1 to 3. 
     After the driving support ECU  10  determined, at the step S 31 , that the abnormality flag Fe is “1”, the driving support ECU  10  proceeds to a step S 61 , and outputs a no-driving-operation warning instruction to the warning ECU  80 . Accordingly, the warning ECU  80  makes a warning sound from the buzzer  81 , makes a warning lamp blink on the indicator  82 , and displays a warning message urging the driver to operate any one of “the accelerator pedal  11   a , the brake pedal  12   a , and the steering wheel SW”. 
     Subsequently, the driving support ECU  10  determines, at a step S 62 , whether or not the driver is in a state where the driver does not perform any driving operation (a state-with-no-driving-operation). This determination process may be the same as the determination processes in the step S 13  in the routine under the normal state, or may require a detection of a more specific driving operation than the above-mentioned driving operations. The driving support ECU  10  proceeds to the step S 32  when the state where the driver does not perform any driving operation remains unchanged. 
     When the driving operation by the driver has been detected (S 62 : Yes) in midst of repeating the processes stated above, the driving support ECU  10  proceeds to a step S 63  and transmits a cancel signal (a signal representing that the driver is not in the abnormal state and that the rescue of the driver and the support for other vehicles became unnecessary) to the help net center HNC. It should be noted that when the help signal has not been transmitted to the help net center HNC yet at this point in time, the process of the step  63  is not necessary. 
     Next, the driving support ECU  10  sets, at a step S 64 , the abnormality flag Fe to “0”, and tentatively terminates the routine under the abnormal state. In this case, the processes such as the deceleration control of the own vehicle, the warning, the alert to the following vehicle, and so on which had been performed until that time are terminated, and a usual vehicle control (a vehicle control based only on the operations by the driver) will be resumed. In addition, after that, the routine under the normal state ( FIG.  3   ) will substantially function in place of the routine under the abnormal state. 
     According to the modification example 4 of the routine under the abnormal state described above, in a case when it has been detected that the driver&#39;s state comes back to the normal state from the abnormal state after having transmitted the help signal to the help net center HNC, the cancel signal is transmitted to the help net center HNC. Accordingly, a rescue of the driver, a support for other vehicles, and the like can be canceled properly. 
     Modification Example 1 of the Routine Under the Normal State 
     Next, a modification example 1 of the routine under the normal state will be described. In this modification example 1, the driving support ECU  10  repeatedly determines whether or not “the driver is in the abnormal state in which the driver loses the ability to drive the vehicle” while the vehicle is traveling. The driving support ECU  10  classifies a current state of the driver into the following three phases, “normal”, “temporarily abnormal”, and “regularly abnormal”, and performs processes corresponding to each phase. When the driver has been first determined to be in the abnormal state, the driving support ECU  10  changes the state of the driver from “normal” which had been set until that time to “temporarily abnormal”. 
     When the driving support ECU  10  sets the driver&#39;s state to “temporarily abnormal”, the driving support ECU  10  warns the driver for urging the driver to conduct driving operations, and forces the vehicle to decelerate at a constant deceleration. It is preferred that the driving support ECU  10  starts the LKA if the LKA has not been conducted. 
     When the driver resumes the driving operations after having recognized the warning or the deceleration of the vehicle, the driving support ECU  10  detects the driving operations by the driver and changes the driver&#39;s state from “temporarily abnormal” which had been set until that time back to “normal”. In this case, the warning to the driver and the deceleration of the vehicle which had been performed until that time are terminated. 
     On the other hand, when a predetermined time has passed without any driving operation by the driver being conducted in spite of warning to the driver and decelerating the own vehicle, it is highly likely that the driver is in the abnormal state. Therefore, when the vehicle speed decreases to a predetermined speed after the deceleration of the own vehicle was started and when a duration time during which the driver&#39;s state is set to “temporarily abnormal” becomes more than or equal to the predetermined time, the driving support ECU  10  sets the driver&#39;s state to “abnormal”. 
     The driving support ECU  10  sets the current driver&#39;s state, classifying the state into “normal”, “temporarily abnormal”, and “abnormal”, and stores the set state. A temporary abnormality flag Fet and an abnormality flag Fe are used as information showing the driver&#39;s state. The value of the temporary abnormality flag Fet being “1” means that the current state of the driver is “temporarily abnormal”. The value of the abnormality flag Fe being “1” means that the current state of the driver is “abnormal”. The values of the temporary abnormality flag Fet and the abnormality flag Fe being both “0” means that the current state of the driver is “normal”. At a point in time when the ignition key is turned on, the temporary abnormality flag Fet and the abnormality flag Fe are initialized to be set to “0”, respectively (Fet=0, Fe=0). 
       FIG.  9    shows a flowchart showing the modification example 1 of the routine under the normal state. When the ignition switch is turned on, the routine under the normal state of this modification example 1 starts in place of the routine under the normal state of the embodiment ( FIG.  3   ). It should be noted that this routine under the normal state is activated when the ACC is being conducted. 
     The driving support ECU  10  determines, at a step S 101 , whether or not the abnormality flag Fe is “0”. The driving support ECU  10  makes an “Yes” determination at the step S 101  since the abnormality flag Fe has been initialized right after the ignition switch was turned on. In this case, the driving support ECU  10  proceeds to a step S 102  to determine whether or not the temporary abnormality flag Fet is “0”. The driving support ECU  10  makes an “Yes” determination at the step S 102  since the temporary abnormality flag Fet has been initialized as well right after the ignition switch was turned on. 
     In this case, the driving support ECU  10  proceeds to a step S 103  to determine whether or not the vehicle speed SPD is more than or equal to the abnormality determination permission vehicle speed SPD 0  set in advance. The driving support ECU  10  tentatively terminates this routine under the normal state in a case when the vehicle speed SPD is less than the abnormality determination permission vehicle speed SPD 0 . 
     In a case when the vehicle speed SPD is determined to be more than or equal to the abnormality determination permission vehicle speed SPD 0  (S 103 : Yes), the driving support ECU  10  determines, at a step S 104 , whether or not the driver is in a state where the driver does not perform any driving operation (a state-with-no-driving-operation). A method for determining the state-with-no-driving-operation is the same as the method of the step S 13  in the embodiment. 
     In a case when the current state is not the state-with-no-driving-operation (S 104 : Yes), the driving support ECU  10  clears, at a step S 105 , a value of a temporary abnormality determination timer te 1  to zero and tentatively terminates the routine under the normal state. The value of the temporary abnormality determination timer te 1  is set to “0” when the ignition switch is turned on. 
     When the state-with-no-driving-operation is detected as a result of repeating the processes stated above, the driving support ECU  10  increases, at a step S 106 , the value of the temporary abnormality determination timer te 1  by “1”. Therefore, the value of the temporary abnormality determination timer te 1  represents a time during which the state-with-no-driving-operation continues. 
     Next, the driving support ECU  10  determines, at a step S 107 , whether or not the value of the temporary abnormality determination timer te 1  is more than or equal to a temporary abnormality confirmation time te 1   ref  set in advance. When the duration time of the state-with-no-driving-operation is less than the temporary abnormality confirmation time te 1   ref , the driving support ECU  10  tentatively terminates the routine under the normal state. 
     When an operation by the driver is detected (S 104 : Yes) in the middle of the repetition of the processes stated above, the value of the temporary abnormality determination timer te 1  is cleared to zero at the step S 105 . 
     On the other hand, when the value of the temporary abnormality determination timer te 1  reaches the temporary abnormality confirmation time te 1   ref  without any driving operations by the driver being detected (S 107 : Yes), the driving support ECU  10  proceeds to a step S 108  to set the temporary abnormality flag Fet to “1”. A timing at which the temporary abnormality flag Fet has been set to “1” is a timing at which the driving support ECU  10  has first determined that the driver is in the abnormal state where the driver loses the ability to drive the vehicle (that is, has temporarily determined that the driver is in the abnormal state). After the temporary abnormality flag Fet was set to “1”, a determination at the step S 102  becomes “No”, and after that, the processes of the step S 103  to the step S 108  are skipped and processes after a step S 109  will be repeatedly performed. 
     It should be noted that when the temporary abnormality flag Fet is set to “1”, or when the abnormality flag Fe is set to “1”, the driving support ECU  10  is preferred to automatically perform the LKA. That is, it is preferable that the driving support ECU  10  forcibly perform the LKA even when the operation switch  18  is not selected to perform the LKA. Accordingly, even when the driver does not perform the steering operation, the own vehicle can be made to travel along the target traveling line (the central position of the left and right white lines). 
     In addition, when the temporary abnormality flag Fet is set to “1”, or when the abnormality flag Fe is set to “1”, the driving support ECU  10  stops the ACC, and makes the vehicle decelerate or travel at a constant speed as described later. 
     The driving support ECU  10  determines, at a step S 109 , whether or not the driver is in the state where the driver does not perform any driving operation (the state-with-no-driving-operation). This determination is the same as the determination process of the step S 104 . When the vehicle is in the state-with-no-driving-operation (S 109 : No), the driving support ECU  10  proceeds to a step S 110  to increase a value of an abnormality determination timer te 2  by “1”. The value of the abnormality determination timer te 2  is set to “0” when the ignition switch is turned on. 
     Subsequently, the driving support ECU  10  outputs, at a step S 111 , a no-driving-operation warning instruction to the warning ECU  80 . Accordingly, the warning ECU  80  makes a warning sound from the buzzer  81 , makes a warning lamp blink on the indicator  82 , and displays a warning message urging the driver to operate any one of “the accelerator pedal  11   a , the brake pedal  12   a , and the steering wheel SW”. 
     Subsequently, the driving support ECU  10  determines, at a step S 112 , whether or not the current vehicle speed SPD of the own vehicle is less than or equal to a first vehicle speed SPD 1 . When the vehicle speed SPD is greater than the first vehicle speed SPD 1  (S 112 : No), the driving support ECU  10  decelerates, at a step S 113 , the own vehicle at a deceleration-under-the-temporarily-abnormal-state ae set in advance, and tentatively terminates the routine under the normal state. It should be noted that the first vehicle speed SPD 1  is set to a value lower than the abnormality determination permission vehicle speed SPD 0 . Besides, the deceleration-under-the-temporarily-abnormal-state ae is set to a value, an absolute value thereof is smaller than the absolute value of the deceleration-under-the-abnormal-state a. 
     When the driving operation by the driver is detected (S 109 : Yes) in the middle of the repetition of the processes stated above, the driving support ECU  10  proceeds to a step S 114  to set the temporary abnormality flag Fet to “0”, and at a step S 105 , clears the value of the abnormality determination timer te 2  to zero. Therefore, the value of the abnormality determination timer te 2  represents a time during which the state-with-no-driving-operation continues after the temporary abnormality flag Fet was set to “1”. 
     On the other hand, when the vehicle speed SPD becomes less than or equal to the first vehicle speed SPD 1  without any driving operation by the driver being detected, the driving support ECU  10  proceeds to a step S 116  to determine whether or not the value of the abnormality determination timer te 2  is more than or equal to an abnormality confirmation time te 2   ref . When the value of the abnormality determination timer te 2  is less than the abnormality confirmation time te 2   ref  (S 116 : No), the driving support ECU  10  keeps the vehicle speed at the current vehicle speed at a step S 117 . In this case, the driving support ECU  10  outputs to the engine ECU  30  and the brake ECU  40  an instruction signal for making the own vehicle travel at a constant speed of the current vehicle speed SPD obtained based on the signal from the vehicle speed sensor  16 . Accordingly, a traveling state of the own vehicle is switched from a decelerated traveling which has been performed until that time to a traveling at a constant speed (a constant speed traveling). It should be noted that the vehicle speed kept at the step S 117  is preferred to be set by a method similar to the method of the aforementioned step S 35 . 
     The driving support ECU  10  repeats the processes stated above, and when the value of the abnormality determination timer te 2  has become more than or equal to the abnormality confirmation time te 2   ref  (S 116 : Yes), the driving support ECU  10  sets, at the step S 118 , the abnormality flag Fe to “1” in place of the temporary abnormality flag Fet (Fet=0, Fe=1). Accordingly, it is confirmed that the driver is in the abnormal state. 
     According to the modification example 1 of the routine under the normal state described above, when the state-with-no-driving-operation has continued for more than or equal to the temporary abnormality confirmation time te 1   ref  (S 107 : Yes), the driver&#39;s state is set to “temporarily abnormal” (S 108 ), the warning is raised to the driver (S 111 ), and the deceleration of the vehicle is started (S 113 ). Then, when the vehicle speed SPD has decreased less than or equal to the first vehicle speed SPD 1  with the state-with-no-driving-operation being kept, if the state-with-no-driving-operation has not continued for more than or equal to the predetermined time (the abnormality confirmation time te 2   ref ) from the point in time at which “temporarily abnormal” was set, a traveling state of the own vehicle is switched from the decelerated traveling to the constant speed traveling. Accordingly, the own vehicle is made to wait with a state in which the own vehicle is traveling. By making the vehicle travel at a constant speed as mentioned above, it becomes possible to ensure a time for determining whether or not the driver is in the abnormal state. Therefore, the help signal can be transmitted to the help net center HNC at a timing at which the determination accuracy (estimation accuracy) of the driver&#39;s abnormal state has been surely raised (at a timing at which a possibility that the driver is in the abnormal state has become very high). Accordingly, erroneous reports to the help net center HNC can be suppressed. 
     It should be noted that in this example, a switch from “temporarily abnormal” to “abnormal” is performed based on both of the vehicle speed SPD and the elapsed time after the driver&#39;s state having been set to “temporarily abnormal”. However, the switch from “temporarily abnormal” to “abnormal” is not necessarily performed based on these two conditions. For example, the switch from “temporarily abnormal” to “abnormal” may be performed based only on either of the following two conditions; one is a condition that the vehicle speed SPD has decreased less than or equal to the first vehicle speed SPD 1  with the state-with-no-driving-operation being kept after the driver&#39;s state having been set to “temporarily abnormal”, and the other is a condition that the state-with-no-driving-operation has continued for more than or equal to the abnormality confirmation time te 2   ref  after the driver&#39;s state having been set to “temporarily abnormal”. Further, other conditions may be also combined. 
     The vehicle traveling control apparatuses according to the present embodiment and modification examples have been described. However, the present invention is not limited to the aforementioned embodiment and the modification examples and may adopt various modifications within a scope of the present invention. 
     For example, in the present embodiment, the abnormality determination of the driver is performed based on the duration time of the state-with-no-driving-operation. However, the abnormality determination of the driver may be performed by making use of a so-called “driver monitor technique” which is disclosed in Japanese Patent Application Laid-Open (kokai) No. 2013-152700 and the like. More specifically, a camera for photographing a driver is provided on an interior member of a vehicle (for example, a steering wheel, a pillar, and the like). The driving support ECU  10  monitors a direction of a driver&#39;s line of sight or a driver&#39;s face direction using the photographed image by the camera. The driving support ECU  10  determines that the driver is in the abnormal state when the driver&#39;s line of sight or the driver&#39;s face direction has been in a certain direction for more than or equal to a predetermined time, wherein the certain direction is a direction to which the driver&#39;s line of sight or the driver&#39;s face direction does not face while driving normally. 
     In addition, the abnormality determination of the driver may be performed using the confirmation button  20 . More specifically, the driving support ECU  10  urges the driver to operate the confirmation button  20  by the indication and/or the sound every time a first time elapses, and determines that the driver is in the abnormal state when a state with no operation of the confirmation button  20  has continued for more than or equal to a second time longer than the first time. 
     The abnormality determination using the photographed image or the confirmation button  20  described above can be used also when performing the determination of “temporarily abnormal” (S 104 ) and the abnormality continuation determination after reporting to the help net center HNC (S 62 ). 
     Further, in the present embodiment, the abnormality determination of the driver is performed under the situation where a traveling support control (ACC in the present embodiment) which makes the vehicle travel without the accelerator pedal operation by the driver is being performed, and when the driver&#39;s abnormality is detected, the traveling control which makes the vehicle decelerate or stop in place of ACC is performed. However, even under the situation where the ACC is not being performed, when the driver&#39;s abnormality is detected, the traveling control which makes the vehicle decelerate or stop may be performed by conducting the aforementioned each control routine.