JP2019038474A - Automatic steering system - Google Patents

Abstract

To provide an automatic steering system which can be converted into a manual operation without disturbing behavior of a vehicle at abnormal end time of automatic steering.SOLUTION: An automatic steering system comprising a steering control device which controls a steering gear, and a steering support device which performs such automatic steering as to control the steering control device and travels a vehicle along a target course shape. The steering control device comprises: a storage part which stores traffic lane shape information calculated from map information; an abnormality diagnosis part which detects occurrence of a failure such that input of a control signal from the steering support device is interrupted; and a future course shape changeover part which determines whether a traffic lane change operation is continued or not based on the traffic lane shape information when the failure occurs during the traffic lane change operation of the vehicle.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an automatic steering system that controls a steering control device of a vehicle.

  For example, as disclosed in Japanese Patent Application Laid-Open No. 2002-175597, an external environment recognition device that recognizes the environment around the vehicle, such as the shape of a road ahead of the vehicle, is provided, and the vehicle is automatically operated based on the recognition result of the device. A traveling control system that performs driving is known.

JP 2002-175597 A

  In a vehicle capable of automatic driving, if a failure occurs in a device related to automatic driving due to, for example, a failure of an external environment recognition device or a cable disconnection, the control of automatic driving abnormally ends immediately. Until the driver of the vehicle recognizes the abnormal end of automatic driving by a warning sound or the like and starts manual driving, the vehicle is not steered, so the behavior of the vehicle may be disturbed during this period. is there.

  The present invention solves the above-described problems, and an object thereof is to provide an automatic steering system capable of shifting to manual driving without disturbing the behavior of the vehicle at the time of abnormal termination of automatic driving.

  An automatic steering system according to an aspect of the present invention calculates a target course shape from at least one of a steering control device that controls a steering device including an actuator that changes a steering angle of a vehicle, and external environment information and map information of the vehicle. The steering control device is controlled on the basis of the target course shape and the state quantity output from the state quantity detection device for detecting the behavior of the vehicle, and the steering is performed to automatically run the vehicle along the target course shape. An automatic steering system comprising: a support device, wherein either one of the steering control device and the steering support device is based on at least one of the external environment information and the map information until a predetermined time later The vehicle lane in which the vehicle is traveling and one or two adjacent to the vehicle lane within a distance predicted to travel the vehicle. A lane shape calculation unit that calculates lane shape information indicating the shape and attribute of an adjacent lane, and the steering control device includes a future route shape that is the target route shape from a present time to a predetermined time later, the state quantity, A storage unit that stores the lane shape information, an abnormality diagnosis unit that detects the occurrence of a failure in which the input of a control signal from the steering assist device is interrupted, and the vehicle is in the own lane during the automatic steering. When the obstacle occurs during the lane change operation from the vehicle to the adjacent lane, it is determined whether to continue the lane change operation based on the lane shape information, and it is determined not to continue the lane change operation In this case, the future route shape switching unit for rewriting the future route shape stored in the storage unit based on the lane shape information of the own lane, and the obstacle occurs during the automatic steering. Case, and an instruction value calculating unit said vehicle along said future path shape stored in the storage unit to control the steering device so that the vehicle travels.

  ADVANTAGE OF THE INVENTION According to this invention, the automatic steering system which can transfer to manual driving | operation without disturbing the behavior of a vehicle at the time of the abnormal end of automatic driving | operation can be provided.

It is a block diagram which shows the structure of an automatic steering system. It is a flowchart of a lane change continuation determination process. It is a flowchart which shows operation | movement of a steering control apparatus. It is a figure which shows the outline | summary of the calculation method of the 3rd steering instruction value by the instruction value calculating part at the time of network abnormal state generation | occurrence | production. It is a figure which shows the outline | summary of the calculation method of the 2nd steering instruction value by the instruction value calculating part at the time of steering instruction abnormal state generation | occurrence | production.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the drawings used for the following description, the scale of each component is made different in order to make each component recognizable on the drawing. It is not limited only to the quantity of the component described in (1), the shape of the component, the ratio of the size of the component, and the relative positional relationship of each component.

  An automatic steering system 100 according to the present embodiment shown in FIG. 1 is a device that is mounted on a vehicle and controls the operation of the steering device 1 provided in the vehicle. The steering device 1 is an electric power steering device that includes an electric actuator, for example, and changes the steering angle of the vehicle by the output of the electric actuator. The automatic steering system 100 executes the automatic steering in the automatic driving function and the driving support function of the vehicle by controlling the steering device 1.

  The automatic steering system 100 includes a steering assist device 10 and a steering control device 20. The vehicle also includes a steering device 1, an outside vehicle communication device 2, a state quantity detection device 3, a notification unit 4, and a communication network 5.

  In the present embodiment, as an example, the steering assist device 10, the steering control device 20, the vehicle exterior communication device 2, and the state quantity detection device 3 are connected to the communication network 5 and perform data communication with each other via the communication network 5. .

  The out-of-vehicle communication device 2 includes a wireless communication device and transmits / receives information to / from a communication device outside the vehicle. The out-of-vehicle communication device 2 performs so-called inter-vehicle communication that directly communicates with other vehicles existing in the communication area. Moreover, the form which performs what is called road-to-vehicle communication which communicates with the wireless base station which exists in a communication area may be sufficient as the external vehicle communication apparatus 2. FIG. The out-of-vehicle communication device 2 receives information on the position and speed of other vehicles existing in the communication area, information on lane restrictions on the road on which the vehicle is traveling, and the like. Note that the vehicle may not include the out-of-vehicle communication device 2.

  Information on the state quantity output from the external communication device 2 is input to the steering assist device 10 via the communication network 5. Note that communication between the vehicle exterior communication device 2 and the steering assist device 10 may be performed using a dedicated communication cable without using the communication network 5.

  The state quantity detection device 3 includes a plurality of sensors that detect the state quantity of the vehicle. The vehicle state quantity includes at least a vehicle speed V that is the speed of the vehicle, an acceleration α in the longitudinal direction of the vehicle, a yaw rate Yawr that is an angular velocity in the yaw direction of the vehicle, and a steering angle of the steering device 1. That is, the state quantity detection device 3 includes at least a vehicle speed sensor, an acceleration sensor, a yaw rate sensor, and a steering angle sensor. Since these sensors are well-known techniques, detailed description is omitted. Note that since the acceleration α in the longitudinal direction of the vehicle can be calculated from the vehicle speed V, the state quantity detection device 3 may not include an acceleration sensor.

  Information on the state quantity output from the state quantity detection device 3 is input to the steering assist device 10 and the steering control device 20 via the communication network 5. Communication between the state quantity detection device 3 and the steering assist device 10 and the steering control device 20 may be performed using a dedicated communication cable without using the communication network 5.

  The notification unit 4 includes, for example, a display device that displays images and characters, a light emitting device that emits light, a speaker that emits sound, a vibrator that emits vibration, or a combination thereof, and the like from the automatic steering system 100 to the driver. Output information.

  The steering assist device 10 includes a map information recognition device 11, an external environment recognition device 12, and an automatic steering instruction value calculation unit 13.

  The map information recognition device 11 stores map information and a positioning device 11a that detects the current position (latitude, longitude) of the vehicle using at least one of a satellite positioning system (GNSS), an inertial navigation device, and road-to-vehicle communication. A map information storage unit 11b.

  The map information recognition device 11 recognizes the shape of the traveling road ahead of the vehicle based on the current position of the vehicle detected by the positioning device 11a and the map information stored in the map information storage unit 11b.

  The map information includes information indicating the shape of the road such as the curvature of the road, the gradient of the longitudinal section, and the state of intersection with another road. The map information includes information indicating the lane attributes of the road. The lane attributes are, for example, information such as a main line, an approach road that enters the main line, and an exit path that leaves the main line. The lane attributes also include information on the traveling lane and the overtaking lane. The road attribute information may be determined by the external environment recognition device 12 described later.

  The external environment recognition device 12 is based on information from cameras and sensors for recognizing the external environment of the vehicle and information from the external communication device 2 and the shape of the road ahead of the vehicle and objects existing on and around the road. Is recognized, and this information is output as external environment information.

  The external environment recognition device 12 includes, for example, a stereo camera that keeps the front of the vehicle within the field of view, and recognizes the environment ahead of the vehicle by performing known image processing or the like on the image captured by the stereo camera. The external environment recognition device 12 recognizes linear markings provided on the road surface, other vehicles on the road surface, pedestrians, and the like. A linear marking is a linear or dashed road marking formed on a road surface along the left and right boundaries of a lane to indicate a lane. The external environment recognition device 12 includes a radar device in addition to the camera, and detects a relative position and a relative speed of the other vehicle traveling on the side or rear of the vehicle with respect to the vehicle.

  That is, the external environment information includes one or more other vehicles traveling around the vehicle, calculated based on at least one of information from the external communication device 2 and information detected by the stereo camera or the radar device. , Proximity vehicle information that is information on the relative position and relative speed with respect to the vehicle is included. The external environment recognition device 12 outputs the proximity vehicle information to the steering control device 20 described later.

  The automatic steering instruction value calculation unit 13 is composed of a computer having a CPU, ROM, RAM, input / output device and the like connected to a bus. The automatic steering instruction value calculation unit 13 has a shape of a travel path on which the vehicle travels based on at least one of map information output from the map information recognition device 11 and external environment information recognized by the external environment recognition device 12. A target course shape is calculated.

  In addition, the automatic steering instruction value calculation unit 13 is configured to calculate a state quantity (yaw angle deviation, lateral position deviation, etc.) with respect to a target course shape recognized by the map information recognition device 11 or the external environment recognition device 12 during automatic steering of the vehicle. Based on the state quantity detected by the state quantity detection device 3, a first steering instruction value, which is control data output to the steering device 1 in order to drive the vehicle along the target course shape, is calculated. The first steering instruction value is information that becomes a target value of steering that the steering device 1 should execute so that the vehicle travels along the target course shape. In the present embodiment, the first steering instruction value is, for example, a target steering angle value that the steering device 1 should change. The first steering instruction value may be a value of a steering torque that should be generated by the electric actuator provided in the steering device 1.

  The first steering instruction value output from the automatic steering instruction value calculation unit 13 is input to the steering control device 20 described later.

  In addition, the automatic steering instruction value calculation unit 13 is based on at least one of the map information and the external environment information, and information on a future course shape that is a target course shape that causes the vehicle to travel by A seconds after a predetermined time from the present time. Is calculated. The predetermined time A is, for example, about 5 seconds. The automatic steering instruction value calculation unit 13 outputs information on the future course shape to the steering control device 20 described later. The calculation of the future course shape may be performed by the steering control device 20 described later.

  The lane shape calculation unit 14 is based on at least one of the external environment information and the map information, and the vehicle lane in which the vehicle is traveling within the distance that the vehicle is expected to travel within a predetermined time A seconds after the present time. Lane shape information indicating the shape and attributes of one or two adjacent lanes adjacent to the host lane is calculated. Adjacent lanes include branch roads and exit roads. That is, the lane shape information is information on the shapes and attributes of all lanes that may travel within about 5 seconds from the present time. The lane shape information may include information on the shapes and attributes of all lanes on the road on which the vehicle is traveling. The lane shape calculation unit 14 outputs lane shape information to the steering control device 20 described later.

  The steering control device 20 is composed of a computer having a CPU, ROM, RAM, input / output device and the like connected to a bus. The steering control device 20 includes a storage unit 21, an abnormality diagnosis unit 23, a future course shape switching unit 24, an instruction value calculation unit 25, and a switching unit 26. Further, the steering control device 20 is electrically connected to the steering device 1. These components included in the steering control device 20 may be implemented as separate hardware that executes individual functions, or software such that individual functions are achieved by the CPU executing a predetermined program. May be implemented.

  The storage unit 21 stores the latest future course shape, lane shape information, proximity vehicle information, and state quantities. The state quantity is the latest state quantity data output from the state quantity detection device 3. The vehicle state quantity stored in the storage unit 21 includes at least a vehicle speed V that is the speed of the vehicle, an acceleration α in the longitudinal direction of the vehicle, a yaw rate Yawr that is an angular velocity in the yaw direction of the vehicle, and the steering angle of the steering device 1. included.

  The future course shape, lane shape information, proximity vehicle information, and state quantity stored in the storage unit 21 are constantly updated at a predetermined cycle. Therefore, the future course shape, lane shape information, proximity vehicle information, and state quantity stored in the storage unit 21 are always the latest values. In addition, each update period of future course shape, lane shape information, proximity vehicle information, and state quantity may be the same, and may differ.

  The abnormality diagnosis unit 23 detects the occurrence of a communication network abnormality state in which the communication network 5 has failed during automatic steering, and the occurrence of a steering instruction abnormality state in which the steering assist device 10 has failed during automatic steering. And detection.

  The network abnormal state is a state in which data communication via the communication network 5 is impossible. The steering instruction abnormal state is a state in which information indicating that a failure has occurred in its own operation is output from the steering assist device 10, or the steering assist is performed even though the communication network 5 is operating normally. In this state, data communication with the device 10 is not possible.

  That is, in a network abnormal state, the steering control device 20 receives the first steering instruction value, the future course shape information, and the lane shape information output from the steering assist device 10 and is output from the state quantity detection device 3. It becomes impossible to receive information on the state quantity. Further, when the steering instruction is abnormal, the steering control device 20 cannot receive the first steering instruction value, the future course shape, and the lane shape information received from the steering assist device 10. However, it is possible to receive state quantity information output from the state quantity detection device 3.

  The future course shape switching unit 24 is stored in the storage unit 21 when a fault of a network abnormal state or a steering instruction abnormal state occurs during a lane change operation from the own lane to the adjacent lane during automatic steering. It is determined whether or not to continue the lane change operation based on the existing lane shape information. If it is determined that the lane change operation is not continued, the future course shape switching unit 24 rewrites the future course shape stored in the storage unit 21 based on the lane shape information of the own lane.

  The lane change operation from the own lane to the adjacent lane is a period from when the vehicle starts changing lanes until all the wheels of the vehicle enter the adjacent lane. During the lane change operation, when no failure in the network abnormal state or the steering instruction abnormal state has occurred, the future course shape stored in the storage unit 21 is calculated by the steering assist device 10. The shape is directed toward the adjacent lane.

  In the event that a network abnormal state or steering instruction abnormal state failure occurs during the lane change operation, the future course shape switching unit 24 is stored in the storage unit 21 so that the vehicle travels in the own lane. Rewrite the future course shape.

  In addition to the lane shape information stored in the storage unit 21, the future course shape switching unit 24 of the present embodiment continues the lane change operation based on the proximity vehicle information stored in the storage unit 21. Determine whether or not.

  FIG. 2 shows a flowchart of the lane change continuation determination process executed by the future course shape switching unit 24. In the lane change continuation determination process, first, in step S500, it is determined whether or not the vehicle is in a lane change operation.

  If it is determined in step S500 that the vehicle is not in a lane change operation, the future course shape switching unit 24 ends the lane change continuation determination process. On the other hand, if it is determined in step S500 that the vehicle is in a lane change operation, the future course shape switching unit 24 proceeds to step S510.

  In step S <b> 510, the future course shape switching unit 24 determines whether the own lane disappears in front of the vehicle based on the lane shape information stored in the storage unit 21. The front of the vehicle is within the range of the lane shape information, that is, within the distance where the vehicle is predicted to travel from the present to A seconds after the predetermined time.

  The disappearance of the own lane occurs when the number of lanes on the road on which the vehicle is traveling decreases or when the own lane is an approach road that enters the main line. As described above, since the lane shape information includes the shape and attributes of the own lane and the adjacent lane, the future course shape switching unit 24 determines whether or not the own lane has disappeared based on the lane shape information. it can.

  If it is determined in step S510 that the own lane will disappear in front of the vehicle, the future course shape switching unit 24 proceeds to step S580. In step S580, the future course shape switching unit 24 determines to continue the lane change operation and ends the lane change continuation determination process. When step S580 is executed, the future course shape stored in the storage unit 21 is calculated by the steering assist device 10 and is shaped toward the adjacent lane.

  On the other hand, if it is determined in step S510 that the own lane does not disappear in front of the vehicle, the future course shape switching unit 24 proceeds to step S520.

  In step S520, the future course shape switching unit 24 determines whether the adjacent lane as the lane change destination is an exit route or a branch route based on the lane shape information stored in the storage unit 21.

  If it is determined in step S520 that the adjacent lane to be the lane change destination is a leaving road or a branch road, the future course shape switching unit 24 proceeds to step S580. As described above, in step S580, the future course shape switching unit 24 determines to continue the lane change operation, and ends the lane change continuation determination process.

  On the other hand, if it is determined in step S520 that the adjacent lane that is the lane change destination is not an exit road or a branch road, the future course shape switching unit 24 proceeds to step S530.

  In step S530, the future course shape switching unit 24 determines, based on the lane shape information stored in the storage unit 21, whether the lane change operation being performed is a lane change from an overtaking lane to a traveling lane. To do.

  If it is determined in step S530 that the lane change operation being performed is a lane change from the overtaking lane to the traveling lane, the future course shape switching unit 24 proceeds to step S580. As described above, in step S580, the future course shape switching unit 24 determines to continue the lane change operation, and ends the lane change continuation determination process.

  On the other hand, if it is determined in step S530 that the lane change operation being performed is not a lane change from the overtaking lane to the traveling lane, the future course shape switching unit 24 proceeds to step S540.

  In step S540, based on the lane shape information stored in the storage unit 21, the future course shape switching unit 24 determines whether or not the lane change operation being performed is a lane change from the traveling lane to the overtaking lane. judge.

  If it is determined in step S540 that the lane change operation being performed is a lane change from the overtaking lane to the traveling lane, the future course shape switching unit 24 proceeds to step S600. In step S600, the future course shape switching unit 24 determines to interrupt the lane change operation. In step S610, the future course shape switching unit 24 rewrites the future course shape stored in the storage unit 21 based on the lane shape information so that the vehicle returns to the own lane, and ends the lane change continuation determination process. To do.

  On the other hand, if it is determined in step S540 that the lane change operation being performed is not a lane change from the traveling lane to the overtaking lane, the future course shape switching unit 24 proceeds to step S550.

  In step S550, the future course shape switching unit 24 determines whether there is another vehicle in the adjacent lane to be the lane change destination based on the proximity vehicle information stored in the storage unit 21.

  If it is determined in step S550 that there is no other vehicle in the adjacent lane that is the lane change destination, the future course shape switching unit 24 proceeds to step S580. As described above, in step S580, the future course shape switching unit 24 determines to continue the lane change operation, and ends the lane change continuation determination process.

  On the other hand, if it is determined in step S550 that there is another vehicle in the adjacent lane that is the lane change destination, the future course shape switching unit 24 proceeds to step S560.

  In step S560, the future course shape switching unit 24 becomes a lane change destination based on the proximity vehicle information stored in the storage unit 21 and the vehicle speed V and acceleration α values stored in the storage unit 21. A collision prediction time TTC with another vehicle traveling in the adjacent lane is calculated. The collision prediction time TTC is stored in the storage unit 21 while the vehicle moves to the adjacent lane while maintaining the vehicle speed V and acceleration α of the vehicle stored in the storage unit 21 and travels in the adjacent lane. This is the time required for the two to come into contact with each other when the speed is maintained.

  Next, in step S570, the future course shape switching unit 24 determines whether or not the predicted collision time TTC for all other vehicles is equal to or greater than a predetermined threshold value ds.

  If it is determined in step S570 that the predicted collision time TTC for all other vehicles is equal to or greater than the predetermined threshold value ds, the future course shape switching unit 24 proceeds to step S580. As described above, in step S580, the future course shape switching unit 24 determines to continue the lane change operation, and ends the lane change continuation determination process.

  On the other hand, if it is determined in step S570 that there is another vehicle with a predicted collision time TTC less than the predetermined threshold value ds, the future course shape switching unit 24 proceeds to step S600. In step S600, the future course shape switching unit 24 determines to interrupt the lane change operation. In step S610, the future course shape switching unit 24 rewrites the future course shape stored in the storage unit 21 based on the lane shape information so that the vehicle returns to the own lane, and ends the lane change continuation determination process. To do.

  The instruction value calculation unit 25 displays the future course shape stored in the storage unit 21 when the abnormality diagnosis unit 23 detects that the network abnormality state or the steering instruction abnormality state is detected during automatic steering of the vehicle. An instruction value to be output to the steering device 1 for driving the vehicle along the vehicle is calculated.

  Specifically, the instruction value calculation unit 25 determines the state quantity input from the state quantity detection device 3 and the future course shape stored in the storage unit 21 when the steering instruction is abnormal during automatic steering. Based on this, a second steering instruction value to be output to the steering device 1 in order to drive the vehicle along the future course shape is calculated.

  In addition, the instruction value calculation unit 25, in the case of a network abnormal state at the time of automatic steering, based on the latest state quantity and the future route shape stored in the storage unit 21, along the future route shape. A third steering instruction value that is output to the steering device 1 to drive the vehicle is calculated.

  The switching unit 26 controls the steering device 1 based on the first steering instruction value output from the steering assist device 10 when the automatic steering is not in the network abnormal state or the steering instruction abnormal state, and the steering instruction abnormality is detected. When the state is in the state, the steering device 1 is controlled based on the second steering instruction value output from the instruction value calculation unit 25, and when the network is in an abnormal state, the second value output from the instruction value calculation unit 25 is controlled. 3. Steering device 1 is controlled based on the steering instruction value.

  That is, when the operations of the steering assist device 10, the state quantity detection device 3, and the communication network 5 are normal, the automatic steering system 100 automatically detects the vehicle based on the first steering instruction value calculated by the steering assist device 10. Steer.

  Further, the automatic steering system 100 is in a case where a failure occurs in the steering assist device 10 during automatic steering of the vehicle, and the operation of the communication network 5 and the state quantity detection device 3 is in a normal steering instruction abnormal state. The vehicle is automatically steered based on the second steering instruction value calculated by the instruction value calculation unit 25 provided in the steering control device 20.

  In addition, the automatic steering system 100 is configured such that the third steering instruction value calculated by the instruction value calculation unit 25 included in the steering control device 20 in a network abnormal state in which a failure occurs in the communication network 5 during automatic steering of the vehicle. Based on this, the vehicle is automatically steered.

  Next, an operation related to automatic steering of the steering control device 20 will be described with reference to a flowchart shown in FIG. The steering control device 20 executes the process shown in FIG. 3 when the vehicle is traveling.

  First, in step S100, the steering control device 20 stands by until an instruction operation for starting automatic steering is input by the driver of the vehicle. When the steering control device 20 determines that an instruction operation for starting automatic steering by the driver has been input, the steering control device 20 starts processing from step S110.

  In the following description, it is assumed that time is represented by a variable t and the current time is t = 0. The vehicle speed, which is the speed of the vehicle, is a variable V (t) that changes with time, and the acceleration in the longitudinal direction of the vehicle is a variable α (t) that changes with time. Let the yaw rate be a variable Yawr (t) that changes over time. Further, a lateral position deviation, which is a deviation amount in the vehicle width direction of the vehicle position with respect to the target route shape, is defined as a variable ErrX (t) that changes with time, and is a deviation amount in the yaw direction of the vehicle direction with respect to the target route shape. The yaw angle deviation is defined as a variable ErrYaw (t) that changes over time.

  In step S110, the steering control device 20 starts storing the future course shape, the lane shape information, the proximity vehicle information, and the state quantity by the storage unit 21, and updating the stored contents. As described above, the future course shape is a target course shape for causing the vehicle to travel from the present to A seconds after a predetermined time. In addition, the lane shape information includes the own lane in which the vehicle is traveling and one or two adjacent lanes adjacent to the own lane within a distance that the vehicle is predicted to travel within a predetermined time A seconds after the present time. It is the information which shows the shape and attribute of.

  The proximity vehicle information is information on a relative position and a relative speed of one or more other vehicles traveling around the vehicle with respect to the vehicle. The state quantity includes a vehicle speed V (0) that is the speed of the vehicle, a longitudinal acceleration α (0) of the vehicle, a yaw rate Yawr (0) that is an angular speed of the vehicle in the yaw direction, and the steering angle of the steering device 1. Including at least.

  In the present embodiment, as an example, the storage unit 21 further stores, as state quantities, a lateral position deviation ErrX (0) and a yaw angle deviation ErrYaw (0) representing the current vehicle deviation from the target course shape. The position deviation ErrX (0) and the yaw angle deviation ErrYaw (0) are values calculated by the steering assist device 10 and are input to the steering control device 20. Since the information stored in the storage unit 21 always changes when the vehicle is running, it is constantly updated when the vehicle is in a normal state.

  Next, in step S <b> 120, the steering control device 20 starts automatic steering for controlling the steering device 1 based on the first steering instruction value calculated by the automatic steering instruction value calculator 13 included in the steering assist device 10. Since the control of automatic steering by the steering assist device 10 is the same as that of a known technique, a detailed description thereof is omitted. Schematically, the automatic steering instruction value calculation unit 13 of the steering assist device 10 determines the target course shape based on the latest recognition results by the map information recognition device 11 and the external recognition device 12, and the map information recognition device 11 and The first steering instruction value is calculated by feedforward control and feedback control based on information such as the yaw angle deviation and lateral position deviation of the host vehicle with respect to the target course shape recognized by the external recognition device 12 and the state quantity of the vehicle. To do.

  After starting the automatic steering based on the first steering instruction value, if the steering control device 20 is in a normal state, the steering control device 20 continues the automatic steering until an instruction operation for ending the automatic steering by the driver is input (step S150). YES)

  If the abnormality detection unit 23 detects that the network is abnormal during execution of automatic steering (YES in step S130), the steering control device 20 proceeds to step S200.

  In step S <b> 200, the steering control device 20 executes a lane change continuation determination process by the future course shape switching unit 24. The lane change continuation determination process is as described above with reference to FIG.

  Next, in step S210, the steering control device 20 notifies the driver via the notification unit 4 that a failure has occurred and automatic steering is to be terminated after A seconds. In step S220, the steering control device 20 continues the automatic steering for controlling the steering device 1 based on the third steering instruction value calculated by the instruction value calculation unit 25 for A seconds from the detection of the occurrence of the network abnormal state.

  An outline of a method for calculating the third steering instruction value by the instruction value calculation unit 25 is shown in FIG. In the following, it is assumed that a network abnormal state has occurred at time t = T1, and the elapsed time from time T1 is δT.

  Since the network abnormal state is a state where communication between both the steering instruction device 10 and the state quantity detection device 3 and the steering control device 20 is interrupted, the network abnormal state is stored in the storage unit 21 after the occurrence of the network abnormal state. The future course shape, the lateral position deviation ErrX (t), the yaw angle deviation ErrYaw (t), and the vehicle state quantity are not updated. Therefore, after the occurrence of the network abnormal state, the storage unit 21 stores the future course shape at the time T1, the lateral position deviation ErrX (T1) and the yaw angle deviation ErrYaw (T1) at the time T1, and the state quantities at the time T1. It is remembered. The state quantities at time T1 are vehicle speed V (T1), acceleration α (T1), and yaw rate Yawr (0). A value surrounded by a broken-line rectangular frame in FIG. 4 is a value stored in the storage unit 21.

  At the time of occurrence of the network abnormal state, the instruction value calculator 25 stores the future course shape and the vehicle state quantity stored in the storage unit 21 at the time of occurrence of the network abnormal state (t = T1), and the progress from the occurrence of the network abnormal state. Based on the time δt, the curvature Ce (0) of the target course is estimated. Specifically, the instruction value calculation unit 25 calculates the current vehicle speed Ve (0) of the vehicle based on the vehicle speed V (T1) and acceleration α (T1) at the time of occurrence of the network abnormal state and the elapsed time δt. presume. Then, the travel distance is calculated from the integrated value of the estimated vehicle speed Ve (0) for the past δt seconds from the present time, the current position of the vehicle on the stored future course shape is estimated, and the target position is determined from this current position and the future course shape. The path curvature Ce (0) is estimated.

  Then, the instruction value calculation unit 25 changes the yaw angle of the vehicle to the yaw angle along the target route based on the current estimated vehicle speed Ve (0) and the estimated curvature Ce (0) of the target route in the target yaw rate calculation unit. The target yaw rate required for the calculation is calculated. The target yaw rate is a value calculated from the current estimated vehicle speed Ve (0) and the estimated curvature Ce (0) of the target course.

  In addition, the instruction value calculation unit 25 performs the lateral position deviation ErrX (T1), which is a deviation in the vehicle width direction of the current vehicle with respect to the target route when the network abnormal state occurs (t = T1), and the current vehicle with respect to the target route. When the yaw angle deviation ErrYaw (T1), which is an angle deviation in the yaw direction, exceeds a predetermined value, the corrected yaw rate calculation unit calculates the corrected yaw rate necessary for returning the vehicle to the future course in the lateral position. Calculation is performed using the deviation ErrX (T1) and the yaw angle deviation ErrYaw (T1). That is, the corrected yaw rate is for compensating for a deviation from the target course of the vehicle due to, for example, a disturbance such as a cant on the road surface or a crosswind.

  Then, the instruction value calculation unit 25 adds the target yaw rate and the corrected yaw rate, and based on this result, the first target rudder angle calculation unit calculates the first target rudder angle. The calculation of the first target rudder angle includes a rudder angle correction gain for correcting a deviation between a preset vehicle motion characteristic and an actual vehicle motion characteristic.

  Then, the instruction value calculation unit 25 outputs the first target steering angle as the third steering instruction value. That is, the third steering instruction value used for automatic steering when a network abnormal state occurs is used for feedforward control of the steering device 1 based on information on the future course shape and the vehicle state quantity stored in the storage unit 21. Only the component of the first target rudder angle is included. The third steering instruction value does not include a component for feedback control of the steering device 1.

  Since the information of the future course shape stored in the storage unit 21 at the time of occurrence of the network abnormal state is within a predetermined time (A seconds), the instruction value calculation unit is A seconds after the occurrence of the network abnormal state. 25 ends the calculation of the third steering instruction value.

  Returning to the flowchart of FIG. 3, the steering control device 20 proceeds to step S300 when the abnormality detection unit 23 detects that the steering instruction is abnormal during execution of automatic steering (YES in step S140). To do.

  In step S300, the steering control device 20 executes a lane change continuation determination process by the future course shape switching unit 24. The lane change continuation determination process is as described above with reference to FIG.

  Next, in step S310, the steering control device 20 notifies the driver via the notification unit 4 that a failure has occurred and automatic steering is to be terminated after A seconds. In step S320, the steering control device 20 continues the automatic steering for controlling the steering device 1 based on the second steering instruction value calculated by the instruction value calculation unit 25 for A seconds from the detection of the occurrence of the network abnormal state.

  FIG. 5 shows an outline of a method for calculating the second steering instruction value by the instruction value calculation unit 25. In the following, it is assumed that the steering instruction abnormal state has occurred at time t = T1, and the elapsed time from time T1 is δT.

  Since the steering instruction abnormal state is a state in which the communication between the steering assist device 10 and the steering control device 20 is interrupted, the future course shape stored in the storage unit 21 after the occurrence of the steering instruction abnormal state, The values of the lateral position deviation ErrX (t) and the yaw angle deviation ErrYaw (t) are not updated. Therefore, after the occurrence of the steering instruction abnormal state, the storage unit 21 stores the future course shape at time T1, the lateral position deviation ErrX (T1) and the yaw angle deviation ErrYaw (T1) at time T1. A value surrounded by a broken-line rectangular frame in FIG. 5 is a value stored in the storage unit 21.

  When the steering instruction abnormal state occurs, the instruction value calculation unit 25 stores the future course shape stored in the storage unit 21 when the steering instruction abnormal state occurs (t = T1) and the elapsed time δt from the occurrence of the steering instruction abnormal state. And the curvature Ce (0) of the target course is estimated based on the current vehicle speed V (0). Specifically, the instruction value calculation unit 25 calculates the travel distance from the integrated value of the vehicle speed for the past δt seconds from the current time, estimates the current position of the vehicle on the stored future course shape, The curvature Ce (0) of the target course is estimated from the future course shape.

  Then, the instruction value calculation unit 25 causes the target yaw rate calculation unit to change the yaw angle of the vehicle to the yaw angle along the target route based on the current vehicle speed V (0) and the estimated curvature Ce (0) of the target route. The target yaw rate necessary for this is calculated. The target yaw rate is a value calculated from the current vehicle speed V (0) and the estimated curvature Ce (0) of the target course.

  In addition, the instruction value calculation unit 25 performs the lateral position deviation ErrX (T1), which is a deviation in the vehicle width direction of the current vehicle with respect to the target route when the steering instruction abnormal state occurs (t = T1), and the current vehicle with respect to the target route. When the yaw angle deviation ErrYaw (T1), which is the angle deviation in the yaw direction, exceeds a predetermined value, the corrected yaw rate calculation unit calculates the corrected yaw rate necessary for returning the vehicle to the future course. The position deviation ErrX (T1) and the yaw angle deviation ErrYaw (T1) are used for calculation. That is, the corrected yaw rate is for compensating for a deviation from the target course of the vehicle due to, for example, a disturbance such as a cant on the road surface or a crosswind.

  Then, the instruction value calculation unit 25 adds the target yaw rate and the corrected yaw rate, and based on this result, the first target rudder angle calculation unit calculates the first target rudder angle. The calculation of the first target rudder angle includes a rudder angle correction gain for correcting a deviation between a preset vehicle motion characteristic and an actual vehicle motion characteristic.

  Further, the instruction value calculation unit 25 uses the yaw rate yaw angle of the vehicle in the second target rudder angle calculation unit based on the value obtained by adding the target yaw rate and the corrected yaw rate and the yaw rate Yawr (0) that is the current vehicle state quantity. A second target rudder angle is calculated for feedback control so that the yaw angle along the target path becomes a yaw angle.

  The instruction value calculation unit 25 outputs a value obtained by adding the first target steering angle and the second target steering angle as a second steering instruction value. In other words, the second steering instruction value used for automatic steering when the steering instruction abnormal state occurs performs feedforward control of the steering device 1 based on the future course shape stored in the storage unit 21 and the current vehicle speed V (0). And a second target rudder angle component for feedback control of the steering device 1 based on the current yaw rate Yawr (0) value of the vehicle.

  Since the information on the future course shape stored in the storage unit 21 at the time of occurrence of the steering instruction abnormal state is within a predetermined time (A seconds), the instruction value is A seconds after the occurrence of the steering instruction abnormal state. The calculation unit 25 ends the calculation of the second steering instruction value.

  As described above, the steering control device 20 according to the present embodiment, during automatic steering, determines the future course shape according to the shape of the road on which the vehicle travels from the present to the future after a predetermined time, and the vehicle speed. Etc. are stored in the storage unit 21.

  When a steering instruction abnormal state occurs in which communication between the steering support device 10 including the map information recognition device 11 and the external recognition device 12 and the steering control device 20 that controls the steering device 1 is interrupted, steering is performed. The control device 20 controls the steering device 1 based on the stored future course shape and vehicle speed and yaw rate information detected in real time by the state quantity detection device 3, and continues automatic steering only for a predetermined period. In this case, since the estimation of the position of the vehicle and the feedback control of the steering angle can be executed in accordance with the change in the state quantity of the vehicle, the automatic steering system 100 performs a predetermined operation along the stored future course shape. The vehicle can be accurately driven only during the period.

  In addition, the steering control device 20 according to the present embodiment stores the memory even when a communication network abnormal state occurs in which communication between both the steering assist device 10 and the state quantity detection device 3 and the steering control device 20 is interrupted. The steering device 1 can be controlled based on the latest future course shape and state quantity, and the automatic steering can be continued so that the vehicle travels along the future course shape for a predetermined period.

  Therefore, according to the automatic steering system 100 of the present embodiment, after a failure occurs in the communication network 5 or after a failure occurs in the steering assist device 10, the vehicle is kept in the future course shape for a predetermined time (A seconds). It is possible to continue the automatic steering that travels along the road.

  According to the automatic steering system 100 of the present embodiment, the automatic steering is abnormally terminated because the automatic steering can be shifted to the manual driving by the driver during the execution period of the automatic steering along the future course shape after the occurrence of the failure. In this case, it is possible to prevent the disturbance of the behavior of the vehicle.

  In addition, the automatic steering system 100 according to the present embodiment refers to FIG. 2 when the vehicle is in a lane change operation when a failure occurs in the communication network 5 or when a failure occurs in the steering assist device 10. As described above, based on the lane shape information and the proximity vehicle information stored in the storage unit 21, it is determined whether or not to continue the lane change operation.

  And in the automatic steering system 100 of this embodiment, when it determines with not continuing lane change operation | movement, as shown to step S610, the future course shape memorize | stored in the memory | storage part 21 returns to the own lane. Rewrite to something. In this case, in the automatic steering during a predetermined period (A second) after the occurrence of the failure, the vehicle travels so as to return to the own lane by interrupting the lane change operation. In the automatic steering system 100 of this embodiment, when it is determined that the lane change operation is to be continued, the vehicle executes the lane change operation in the automatic steering during a predetermined period (A second) after the occurrence of the failure. And move to the adjacent lane.

  More specifically, when the own lane disappears, such as when the number of lanes decreases or the own lane is an approach road that enters the main line, the automatic steering system 100 performs the automatic steering after the occurrence of the obstacle. In step S510, the lane change operation is continued (YES in step S510). If the lane change operation is automatically interrupted when the own lane disappears, the driver must perform a sudden steering angle change operation when shifting to manual operation. The steering system 100 can prevent such a sudden steering angle changing operation.

  Further, when the adjacent lane as the lane change destination is a leaving road or a branch road, the automatic steering system 100 continues the lane change operation in the automatic steering after the occurrence of the obstacle (YES in step S520). If the lane change operation is automatically interrupted when the adjacent lane that is the lane change destination is an exit or branch road, the direction of travel by automatic steering and the direction of travel intended by the driver will be different. End up. In this case, when shifting to manual driving, the driver has to perform a sudden steering angle changing operation. However, the automatic steering system 100 of the present embodiment can prevent such a sudden steering angle changing operation.

  When the lane change is from the overtaking lane to the traveling lane, the automatic steering system 100 continues the lane change operation in the automatic steering after the occurrence of the obstacle (YES in step S530). A lane change from an overtaking lane to a driving lane generally involves a deceleration operation. For this reason, if the lane change from the overtaking lane to the driving lane is interrupted, the vehicle may decelerate in the overtaking lane, and the vehicle may collide with another vehicle traveling behind the overtaking lane. There is. In the automatic steering system 100 of the present embodiment, the lane change from the overtaking lane to the traveling lane is not interrupted, and thus the possibility of such a rear-end collision can be eliminated.

  Further, when the lane change from the traveling lane to the overtaking is made, the automatic steering system 100 interrupts the lane change operation and returns to the own lane in the automatic steering after the occurrence of the obstacle (YES in step S540). In general, other vehicles are traveling in the overtaking lane at a higher speed than the traveling lane. Further, a lane change from a traveling lane to an overtaking lane generally involves an acceleration operation, but this acceleration may not be performed in automatic steering after the occurrence of an obstacle. For this reason, if the lane change from the traveling lane to the overtaking lane is executed, the vehicle may collide with another vehicle traveling behind the overtaking lane. In the automatic steering system 100 of the present embodiment, the lane change from the traveling lane to the overtaking lane is interrupted and returned to the traveling lane, so that the possibility of such a rear-end collision can be eliminated.

  Further, when another vehicle having a collision prediction time TTC less than a predetermined threshold value ds is traveling in the adjacent lane to which the lane is changed, the automatic steering system 100 interrupts the lane changing operation in the automatic steering after the occurrence of the obstacle. Then, return to the own lane (NO in step S570). According to this embodiment, the possibility of a collision with another vehicle in automatic steering after the occurrence of a failure can be eliminated.

  As described above, according to the automatic steering system 100 of the present embodiment, even when the vehicle is in a lane change operation when a failure occurs, it is possible to safely shift to manual driving by the driver, It is possible to prevent disturbance of the behavior of the vehicle when automatic steering ends abnormally.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. An automatic steering system with such a change is also applicable. Moreover, it is included in the technical scope of the present invention.

1 Steering device,
2 External communication device,
3 state quantity detection device,
4 Notification Department,
5 communication network,
10 steering assist device,
11 Road information recognition device,
11a coronation device,
11b Map information storage unit,
11c External communication device,
12 External environment recognition device,
13 Automatic steering instruction value calculation unit,
14 Lane shape calculation unit,
20 steering control device,
21 storage unit,
23 abnormality diagnosis department,
24 Future course shape switching part,
25 indicated value calculation section,
26 switching section,
100 Automatic steering system.

Claims (3)

A steering control device for controlling a steering device including an actuator for changing a steering angle of the vehicle;
A target course shape is calculated from at least one of the external environment information and map information of the vehicle, and the steering control device is controlled based on the target course shape and a state quantity output from a state quantity detection device that detects the behavior of the vehicle. A steering assist device that performs automatic steering for causing the vehicle to travel along the target course shape;
An automatic steering system comprising:
Either one of the steering control device and the steering assist device is based on at least one of the external environment information and the map information, within a distance where the vehicle is predicted to travel by a predetermined time from the present time, A lane shape calculation unit that calculates lane shape information indicating the shape and attributes of the own lane in which the vehicle is traveling and one or two adjacent lanes adjacent to the lane;
The steering control device includes:
A storage unit that stores a future course shape that is the target course shape from the present to a predetermined time later, the state quantity, and the lane shape information;
An abnormality diagnosing unit for detecting the occurrence of a failure in which input of a control signal from the steering assist device is interrupted;
During the automatic steering, when the obstacle occurs during the lane change operation from the own lane to the adjacent lane, it is determined whether to continue the lane change operation based on the lane shape information. A future course shape switching unit that rewrites the future course shape stored in the storage unit based on the lane shape information of the own lane when it is determined that the lane change operation is not continued;
An instruction value calculation unit for controlling the steering device so that the vehicle travels along the future course shape stored in the storage unit when the failure occurs during the automatic steering;
An automatic steering system comprising: The storage unit is calculated based on at least one of the external environment information and information received by an external communication device included in the vehicle, and is relative to the vehicle of another vehicle traveling in the own lane and the adjacent lane. Memorize the proximity vehicle information indicating the position and relative speed,
The future course shape switching unit is configured to change the lane based on the lane shape information and the adjacent vehicle information when the obstacle occurs during the lane change operation from the own lane to the adjacent lane. 2. The automatic steering system according to claim 1, wherein it is determined whether or not to continue the operation. The future course shape switching unit calculates a collision prediction time with the other vehicle traveling in the adjacent lane that is a target of the lane change operation based on the proximity vehicle information, and the collision prediction time is a predetermined value. The automatic steering system according to claim 2, wherein it is determined that the lane change operation is not continued when it is less than a threshold value.

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