AUTOMATIC DRIVING SYSTEM

Abstract

An automated driving system (1) comprising the following: an actuation input quantity detection unit (16) designed to detect a driving actuation input quantity by a driver during automatic driving control for a vehicle; a driver state determination unit (17) designed to determine whether the driver is capable of initiating manual driving during automatic driving control for the vehicle; a driving switching unit (19) designed to perform a switch from automatic driving to manual driving based on the result of a comparison between the driving operation input variable and a driving switching threshold value, which is a threshold for switching from automatic driving to manual driving; and characterized by a threshold setting unit (18) designed to to set the drive switchover threshold to a first drive switchover threshold when the driver state determination unit determines that the driver is in a state where manual driving can be initiated, and to set the drive-to-drive threshold to a second drive-to-drive threshold that exceeds the first drive-to-drive threshold if the driver state determination unit determines that the driver is not in a state in which manual driving can be initiated.

Description

BACKGROUND OF THE INVENTION 1. Field of the invention

[0001] The invention relates to a system for the automatic driving of a vehicle. 2. Explanation of the state of the art

[0002] An automatic driving device disclosed in US patent US 8,670,891 B1 is known for automatic driving control of a vehicle. In this automatic driving device, automatic driving of the vehicle is performed, and the automatic driving is switched to manual driving during the execution of the automatic driving in a case where any quantity from an actuation input at the steering wheel, an actuation input at the accelerator pedal, or a brake actuation input by a driver of the vehicle during automatic driving is equal to or greater than a predetermined threshold.

[0003] It is conceivable that the automatic driving device described above could switch to manual driving as a result of an unintentional manual input from the driver during automatic driving. For example, if the driver accidentally depresses the accelerator pedal, the vehicle could switch to manual driving even if the driver is not ready for manual operation.

[0004] With this in mind, the development of an automatic driving system was desired in this technical field, which prevents the switching to manual driving that is not intended by a driver in the case of manual driving operation that is accidentally entered during automatic driving control.

[0005] German patent DE 10 2014 205 830 A1 discloses a method to prevent an unauthorized driver from taking control of an autonomous vehicle. This is verified using credentials such as photographs (driver's licenses), fingerprints, or similar methods. If a driver attempts to take control without authorization, the vehicle ignores the corresponding inputs.

[0006] German patent DE 10 2012 223 758 A1 teaches a similar procedure to ensure that only a qualified driver takes control. According to this disclosure, when a driver actively requests to take over (for example, by flipping a switch), they are tasked with performing a specific sequence of actions (e.g., repeatedly pressing the accelerator and brake pedals). This sequence can either be predefined or randomly determined each time and communicated anew to the taking-over driver.

[0007] German Patent DE 11 2015 000 759 T5 proposes returning control to the driver when they appear "stressed" by autonomous driving. This handover is intended to calm the stressed driver.

[0008] DE 10 2012 213 965 A1, like the present invention, aims to transfer control to the driver depending on their level of attention. According to this teaching, as long as the vehicle is driving autonomously, the driver is presented with tasks to be solved depending on the traffic situation. This ensures that the driver is always ready to take control. If the driver does not react to the tasks presented (for example, because they are asleep), the vehicle stops.

[0009] Each of these printed documents discloses the features of the preamble of the present claim 1. BRIEF EXPLANATION OF THE INVENTION

[0010] One aspect of the invention is a system for automated driving with the features described in claim 1. Advantageous further developments are the subject of the dependent claims.

[0011] In the aspect described above, the driving switch unit can be configured to perform the switch from automatic driving to manual driving when the driving input value exceeds the driving switch threshold. According to this aspect, the automatic driving system can prevent an unintended switch to manual driving that is not intended by the driver.

[0012] The aspect described above may further include a contact sensor designed to detect the driver's contact with the vehicle's steering wheel, and the driver state determination unit may be designed to determine, based on the result of the contact sensor's detection, whether the driver is capable of initiating manual driving or not. According to this aspect, it can be accurately determined whether the driver is in a state where manual driving can be started or not.

[0013] The aspect described above can further include a biometric information sensor designed to capture the driver's biometric information, whereby the driving state determination unit can be designed to determine, based on the result of the capture by the biometric information sensor, whether the driver is capable of initiating manual driving or not. According to this aspect, it can be accurately determined whether the driver is in a state in which manual driving can be started or not.

[0014] The aspect described above may further include an instrument in the vehicle, whereby the driving state determination unit may be configured to determine, based on whether or not an activation signal from the instrument in the vehicle is received, whether the driver is capable of commencing manual driving. According to this aspect, it can be precisely determined whether the driver is in a state in which manual driving can be initiated.

[0015] The aspect described above may further include a camera designed to image the driver, and the driving state determination unit may be designed to determine, based on an image of the driver captured by the camera, whether the driver is capable of initiating manual driving or not. According to this aspect, it can be accurately determined whether the driver is in a state in which manual driving can be initiated or not.

[0016] In the aspect described above, the driving state determination unit can be configured to determine, based on the driver's posture, gaze direction, facial orientation, or eye opening level, from the image of the driver captured by the camera, whether the driver is capable of initiating manual driving. According to this aspect, it can be accurately determined whether the driver is in a state where manual driving can begin.

[0017] According to the invention, switching to manual driving, which is not intended by the driver, can be prevented even in the case of an accidental manual driving input during automatic driving control. BRIEF EXPLANATION OF THE FIGURES

[0018] Features, advantages and the technical and industrial significance of exemplary embodiments of the invention are described below with reference to the accompanying figures, in which similar reference numerals denote similar elements, and in which: Fig. 1 is a block diagram illustrating an overview of the structure of an automatic driving system according to an embodiment of the invention; Fig. 2. A diagram is shown as an example of a relationship between a driver's state and a driving switchover threshold in which the Fig. 1. The system shown illustrates automatic driving; Fig. 3 is a diagram that provides another example of the relationship between the driver's state and the drive switchover threshold in the in Fig. 1. The system shown illustrates automatic driving; Fig. 4 is a process plan that includes processing for controlling the automated driving of the in Fig. 1 illustrates the automatic driving system shown; Fig. 5 is a flowchart that includes a drive switching processing location of the in Fig. 1 illustrated the system for automatic driving shown; Fig. 6. A process plan is one that includes processing to determine a threshold value of the in Fig. 1 illustrated the system for automatic driving shown; Fig. 7 is a process flowchart that provides an example of the processing for determining the threshold of the in Fig. 1 illustrates the system for automated driving shown; and Fig. 8 is a process flowchart that provides another example of the processing for setting the threshold of the in Fig. 1 illustrates the system for automatic driving shown. DETAILED EXPLANATION OF EXECUTION FORMS

[0019] An embodiment of the invention is described below with reference to the accompanying figures. In the following description, the same reference numerals are used to denote the same or similar elements, and redundant descriptions are omitted.

[0020] Fig. Figure 1 is a diagram illustrating an overview of the structure of a system 1 for automated driving according to the embodiment of the invention. Fig. In this embodiment, the automatic driving system 1 is a device mounted in a vehicle that performs automatic driving control for the vehicle. This automatic driving system 1 is equipped with a function to switch from automatic driving to manual driving in cases where manual driving is performed by a driver during automatic driving control of the vehicle. Automatic driving means a driving mode in which the vehicle is permitted to drive automatically by means of the automatic driving system 1. Manual driving means driving the vehicle by means of manual driving input by the vehicle's driver.

[0021] System 1 for automated driving is equipped with an electronic control unit (ECU) 10. The ECU 10 is an electronic control unit that controls and regulates the vehicle's driving. The ECU 10 is designed to include a computer as its main component, and the computer includes a central processing unit (CPU), read-only memory (ROM), and random access memory (RAM). The ECU 10 will be described in more detail later.

[0022] The ECU 10 is connected to an external sensor 2, a receiver unit 3 for a GPS or global positioning system, an internal sensor 4, a map database 5, a navigation system 6, a human-machine interface (HMI) 7, an actuator 8, a driver status sensor 9, and an actuation input size sensor 20.

[0023] The external sensor 2 is a detection instrument that records an external situation, providing information about the vehicle's surroundings. The external sensor comprises at least one camera, radar, or laser imaging detection and ranging (LIDAR) device.

[0024] The camera is an imaging instrument that captures the external environment around the vehicle. The camera is typically located behind the vehicle's windshield. It can be a monocular or a stereo camera. A stereo camera has two imaging units arranged to create a binocular offset. Depth-direction information is also included in the image captured by the stereo camera. When used as a stereo camera, it can function as an object detection unit, capturing objects such as vehicles ahead and obstacles.

[0025] The radar detects the obstacle outside the vehicle using radio waves such as millimeter waves. It detects the obstacle by transmitting radio waves to the vicinity of the vehicle and receiving the radio waves reflected by the obstacle. The radar then transmits information about the detected obstacle to the ECU.

[0026] The LiDAR detects the obstacle outside the vehicle using light. It measures the distance to a reflection point and detects the obstacle by transmitting light towards the vehicle and receiving the light reflected from the obstacle. The LiDAR transmits information about the detected object to the ECU 10. The camera, LiDAR, radar, and communication instrument do not necessarily need to be arranged in an overlapping manner.

[0027] The GPS receiver 3 measures the vehicle's position, including its latitude and longitude, by receiving signals from at least three GPS satellites. The GPS receiver 3 outputs the measured position information to the ECU 10. Any other device capable of determining the vehicle's latitude and longitude can replace the GPS receiver 3. Furthermore, for verification purposes by comparing a sensor measurement with map information (described later), it is preferable to include a function for measuring the vehicle's orientation.

[0028] The interior sensor 4 is a detection instrument that records vehicle states. The interior sensor 4 is equipped with at least one vehicle speed sensor, one acceleration sensor, or one yaw rate sensor as a sensor that detects a driving state of the vehicle. The vehicle speed sensor is a detector that detects the vehicle's speed. A vehicle wheel speed sensor is used as an example of a vehicle speed sensor. The vehicle wheel speed sensor is located on a wheel of the vehicle or on a part such as a drive shaft that rotates integrated with or synchronously with a vehicle wheel and detects the rotational speed of the vehicle wheel. The vehicle speed sensor outputs the detected vehicle speed information, i.e., the wheel speed information, to the ECU 10. The acceleration sensor is a detector that detects the vehicle's accelerations.The acceleration sensor includes, for example, a longitudinal acceleration sensor, which detects the vehicle's acceleration in a longitudinal direction, and a lateral acceleration sensor, which detects the vehicle's lateral acceleration. The acceleration sensor outputs vehicle acceleration information to the ECU 10. The yaw rate sensor is a detector that detects the yaw rate around a vertical axis through the vehicle's center of gravity. A gyroscope sensor can be used as an example of a yaw rate sensor. The yaw rate sensor outputs the detected yaw rate information of the vehicle to the ECU 10.

[0029] The map database, or map database 5, is a database into which map information is stored. The map database 5 is, for example, stored on a hard disk drive (HDD) mounted in the vehicle. The map information includes, for example, position information for roads, road shape information (such as the number and type of lanes), and position information for intersections and junctions. It is desirable that the map information also includes an output signal from the external sensor 2 to utilize position information for obstructions such as buildings and walls, and a technology for simultaneous localization and mapping (SLAM). The map database 5 can be stored on a computer in a facility such as an information processing center that is capable of communicating with the vehicle.

[0030] The navigation system 6 is a device that guides the vehicle to a destination specified by the driver. The navigation system 6 calculates a route for the vehicle based on the vehicle's position information, measured by the GPS receiver 3, and the map information in the map database 5. The route can be a specific suitable lane in a multi-lane section. For example, the navigation system 6 calculates a target route from the vehicle's position to the destination and informs the driver of the target route using a displayed marker and an audio output from a speaker. The navigation system 6 also outputs information regarding the vehicle's target route to the ECU 10. The navigation system 6 can be stored in the computer within the facility, such as the information processing center, which is capable of communicating with the vehicle.

[0031] The HMI 7 is an interface for information output and input between the passenger in the vehicle and the automatic driving system 1. The HMI 7 is equipped, for example, with a display for visual information for the passenger, a speaker for audio output, and an operating button or touch panel for input by the passenger. When the passenger initiates or stops the automatic driving control, the HMI 7 initiates or stops the automatic driving control, for example, by outputting a signal to the ECU 10. The HMI 7 can output information to the passenger using a wirelessly connected portable information terminal, or it can receive input from the passenger using a portable information terminal.In a case where the input process is being carried out by the passenger, who may also be the driver, the HMI 7 can output a signal of an ongoing process to the ECU 10, indicating that the input process is in progress.

[0032] Actuator 8 is a device that performs automatic driving control for the vehicle. Actuator 8 comprises at least a throttle actuator, a brake actuator, and a steering actuator. The throttle actuator controls the amount of air supplied to a machine, i.e., the throttle opening degree, corresponding to a control signal from the ECU 10, and controls a driving force of the vehicle. In the case where the vehicle is a hybrid or electric vehicle, actuator 8 does not include the throttle actuator, and the driving force is controlled by a control signal from the ECU 10, which is read into a motor as the drive source.

[0033] The brake actuator controls a braking system in response to a control signal from ECU 10 and regulates the braking force applied to the vehicle's wheels. A hydraulic braking system can be used as an example of a braking system. The steering actuator, in response to a control signal from ECU 10, drives an auxiliary motor that controls the steering torque in an electric power steering system. In this way, the steering actuator controls the vehicle's steering torque.

[0034] The driver state sensor 9 is a sensor that detects the driver's state. The driver state sensor 9 includes, for example, a contact sensor or touch sensor 91, a driver detection camera 92, and a biometric information sensor 93. The contact sensor 91 is a sensor that detects the driver's touch of the steering wheel. A pressure-sensitive sensor is used as an example of the contact sensor 91. The contact sensor 91 can also be a capacitive sensor. This contact sensor 91 has, for example, a detection unit installed in the part of the steering wheel held by the driver. Alternatively, two detection units can be installed, one on the right side of the steering wheel and the other on the left side. This contact sensor 91 can be used in combination with a sensor used for another application. The contact sensor 91 outputs a detection signal to the ECU 10.

[0035] The driver detection camera 92 is a camera that captures an image of the driver inside the vehicle. The driver detection camera 92 is designed to capture the driver's upper body, face, eyes, or similar features. Multiple driver detection cameras 92 can be installed. The driver detection camera 92 transmits a captured image of the driver to the ECU 10.

[0036] The biometric information sensor 93 is a sensor that captures biometric information of the driver, such as the driver's brainwaves and pulse. The biometric information sensor 93 is, for example, a wearable device worn by the driver, in the form of glasses, a wristwatch, a ring, a bracelet, or the like. The biometric information sensor 93 outputs the captured biometric information of the driver to the ECU 10. The contact sensor 91, the driver detection camera 92, and the biometric information sensor 93 can be combined to form the driver state sensor 9. Alternatively, only one or two of these can be used.

[0037] The actuation input sensor 20 is a sensor that detects the magnitude of the manual driving input by the driver. A steering angle sensor or a steering torque sensor is used as an example of an actuation input sensor 20. An accelerator pedal travel sensor or an accelerator pedal depressor force sensor can also be used as an actuation input sensor 20. The accelerator pedal travel sensor detects the amount of accelerator pedal depressor. The accelerator pedal depressor force sensor detects the force exerted by the accelerator pedal. A brake pedal travel sensor or a brake pedal depressor force sensor can also be used as an actuation input sensor 20. The brake pedal travel sensor detects the amount of brake pedal depressor. The brake pedal depressor force sensor detects the force exerted by the brake pedal. All of these sensors can be used as an actuation input sensor 20.Alternatively, only some of them can be used instead. For example, the actuation input size sensor 20 outputs the magnitude or force of the driver's depressing of the accelerator pedal and the magnitude or force of the driver's depressing of the brake pedal to the ECU 10.

[0038] The ECU 10 is equipped with a unit 11 for detecting an external situation, a vehicle position detection unit 12, a driving condition detection unit 13, a timetable generation unit 14, a driving control unit 15, an actuation input quantity detection unit 16, a driver condition determination unit 17, a threshold setting unit 18 and a driving switching unit 19.

[0039] Unit 11, for external situation detection, recognizes the external situation around the vehicle based on data from the external sensor 2, such as information from the camera, obstacle information from the radar, and obstacle information from the LiDAR. The external situation includes, for example, road width, road shape, the presence of another vehicle near the vehicle, and obstacles near the vehicle.

[0040] The vehicle position detection unit 12 detects the position of the vehicle on a map based on the vehicle's position information received by the GPS receiver unit 3 and the map information from the map database 5. Hereinafter, the vehicle's position on the map is referred to as a "vehicle position".

[0041] The vehicle state detection unit 13 detects the vehicle's driving state based on data from the internal sensor 4, such as vehicle speed information from the vehicle speed sensor, acceleration information from the acceleration sensor, and yaw rate information from the yaw rate sensor. The vehicle's driving state includes, for example, its speed, acceleration, and yaw rate. Furthermore, the vehicle state detection unit 13 can detect the vehicle's direction of travel based on a temporary change in the vehicle's position.

[0042] The timetable generation unit 14 generates a target route for the vehicle, for example, based on the destination route calculated by the navigation system 6, the vehicle position detected by the vehicle position detection unit 12, and the situation around the vehicle, which is detected by the external situation detection unit 11 and includes the vehicle's position and orientation. The target route is a trajectory of the vehicle along the target route. At this time, the timetable generation unit 14 adjusts the vehicle's path based on the situation of obstacles near the vehicle in such a way as to avoid contact with the obstacle.

[0043] The target route described above also includes a route that is automatically generated based on the external situation and map information when the driver does not explicitly enter a destination. Examples include driving on routes along roads according to the "driving assistance device" disclosed in Japanese patent no. 5382218 (WO 2011 / 158347) and the "automatic driving device" disclosed in Japanese patent application no. 2011-162132.

[0044] The timetable generation unit 14 generates a travel or timetable corresponding to the generated route. In other words, the timetable generation unit 14 generates a timetable corresponding to the destination route, which is predetermined based on at least the external situation, the information regarding the vehicle's environment, and the map information from the map database 5. Preferably, the timetable generation unit 14 outputs the timetable it generates as one of a plurality of sets of the two elements target position p and speed v per destination point in a vehicle-fixed coordinate system, that is, a plurality of configuration coordinates (p, v) for a course of the vehicle. Each target position p has at least one x-coordinate and y-coordinate position in the vehicle-fixed coordinate system or equivalent information. The timetable is not particularly restricted as long as it reflects vehicle behavior.For example, an arrival time t can be used instead of the speed v in the timetable. Alternatively, a different timetable can be used that includes the arrival time t and the vehicle's orientation at that time.

[0045] Normally, future data for a few seconds from the current time is sufficient as a timetable. However, depending on situations such as a right turn at an intersection and overtaking by the vehicle, data for several tens of seconds is required. Accordingly, it is preferable that the number of configuration coordinates of the timetable is variable, as is the distance between the configuration coordinates. Furthermore, a curve connecting configuration coordinates can be approximated by a spline function or the like, and a parameter of the curve can be considered the timetable. Any known method can be used for timetable generation insofar as the method can describe the vehicle's behavior.

[0046] The timetable can consist of data showing transitions in the vehicle's speed, acceleration and deceleration, steering torque, and the like at any given time while the vehicle is traveling along the target route. The timetable can include a speed pattern, acceleration and deceleration patterns, and a steering pattern. The timetable generation unit 14 can generate the timetable in such a way as to minimize the time the vehicle needs to reach the destination.

[0047] The speed pattern, for example, consists of data comprising a target vehicle speed, combined with a time for each target steering position relative to the target steering positions set along the course at a predefined interval of, for example, 1 m. The acceleration and deceleration patterns, for example, consist of data comprising a target acceleration and deceleration, combined with a time for each target steering position relative to the target steering positions set along the course at a predefined interval of, for example, 1 m. The steering pattern consists of data comprising a target steering torque, combined with a time for each target steering position relative to the target steering positions set along the course at a predefined interval of, for example, 1 m.

[0048] The driving control unit 15 controls the vehicle's operation based on the timetable generated by the timetable generation unit 14. The driving control unit 15 outputs a control signal to the actuator 8, corresponding to the timetable. In this way, the driving control unit 15 controls the vehicle's operation so that it is driven automatically according to the timetable. The driving control unit 15 initiates automatic driving control upon an initiation condition, such as the driver pressing a start button for automatic driving control. The driving control unit 15 also terminates automatic driving control, for example, when the driver presses a button to end automatic driving control. Furthermore, the driving control unit 15 terminates automatic driving control when the driving switch unit 19 performs the switch from automatic to manual driving.

[0049] During automatic driving control, the actuation input quantity detection unit 16 detects the magnitude of the actuation input for manual driving, which includes at least one of the driver's steering wheel input, accelerator pedal input, or brake input. For example, the actuation input quantity detection unit 16 detects the magnitude of the manual driving input, which includes steering wheel input, accelerator pedal input, or brake input during automatic driving control of the vehicle, based on detection signals from a steering angle sensor, a steering torque sensor, an accelerator pedal travel sensor, an accelerator pedal depressor force sensor, a brake pedal travel sensor, a brake pedal depressor force sensor, and the like of the interior sensor 4. The steering wheel input quantity is, for example, a steering angle or a steering torque of the steering wheel.The accelerator pedal input variable is, for example, the accelerator pedal depressor amount or the accelerator pedal depressor force. The brake input variable is, for example, the brake pedal depressor amount or the brake pedal depressor force.

[0050] The driver state determination unit 17 determines whether the driver is in a state in which manual driving can be initiated during the vehicle's automatic driving control. For example, the driver state determination unit 17 detects the driver's state during the vehicle's automatic driving control based on at least the detection result of the contact sensor 91 or the image captured by the driver imaging camera 92, and determines, based on the detection result, whether the driver is in a state in which manual driving can be initiated.The driver being in a state where manual driving can be initiated means that the driver is in a state where manual driving can be prepared, and corresponds to a state where the driver is assuming a driving position, a state where the driver is about to assume a driving position, a state where driving is already underway, and so on. The state in which manual driving can be initiated includes, for example, a state where the driver is in contact with the vehicle's steering wheel. The state in which manual driving can be initiated may also include a state where the driver's face or gaze is directed towards the front of the vehicle.

[0051] More precisely, the driver state detection unit 17 can determine, based on a detection signal from the contact sensor 91, whether the driver is in a state in which manual driving can be initiated or not. For example, if the driver is touching the steering wheel, the driver state detection unit 17 determines that the driver is in a state in which manual driving can be initiated or triggered. Conversely, if the driver is not touching the steering wheel, the driver state detection unit 17 determines that the driver is not in a state in which manual driving can be triggered.

[0052] Furthermore, the driver state determination unit 17 can determine, based on the image captured by the driver detection camera 92, whether the driver is in a state in which manual driving can be initiated. In a case where the driver's posture is a predefined driving posture, such as a posture that allows for driving preparation with the face and upper half of the body facing the front of the vehicle, the driver state determination unit 17 determines that the driver is in a state in which manual driving can be initiated. In a case where the driver's posture is, for example, a predefined non-driving posture, such as a posture with the neck bent to operate a portable information terminal, the driver state determination unit 17 determines that the driver is in a state in which manual driving can be initiated.If the driver's head is tilted and the driver's seat back is in a reclined position, the driver state detection unit 17 determines that the driver is not in a state where manual driving can be initiated. Similarly, if the driver's face or gaze is directed towards the front of the vehicle, the driver state detection unit 17 determines that the driver is in a state where manual driving can be initiated. Similarly, if the driver's face or gaze is not directed towards the front of the vehicle, the driver state detection unit 17 determines that the driver is not in a state where manual driving can be initiated. Similarly, if the driver's eyelids are open, the driver state detection unit 17 determines that the driver is in a state where manual driving can be initiated.For example, in a case where the driver's eyelids are not open, the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be initiated.

[0053] Furthermore, the driver state determination unit 17 can determine, based on an activation signal from an instrument in the vehicle such as the HMI 7, whether the driver is in a state in which manual driving can be initiated. For example, if the driver is operating an in-vehicle instrument, such as an audio system, air conditioning, navigation system 6, or HMI 7, the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be initiated. Similarly, if a predefined time period, such as 1.0 second, has not yet elapsed after the driver has ceased operating an in-vehicle instrument, the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be initiated.The driver status determination unit 17 does not necessarily have to distinguish whether a subject performing the ongoing in-vehicle instrument operation is the driver or the passenger.

[0054] The driver state determination unit 17 can determine, based on a reading from the biometric information sensor 93, such as a brainwave or pulse reading, whether the driver is in a state where manual driving can be initiated. In cases where the driver is in an unconscious state, including situations where the driver's attention is at or below a predefined threshold, the driver state determination unit 17 determines that the driver is not in a state where manual driving can be initiated. Known methods can be used to calculate the driver's attention.

[0055] Threshold setting unit 18 sets a drive-switch threshold. The drive-switch threshold is a threshold used to switch from automatic to manual driving. The drive-switch threshold is set for each type of actuation input used to switch the vehicle from automatic to manual driving. Examples of actuation input types include steering wheel angle, steering wheel torque, accelerator pedal depress amount, accelerator pedal depress force, brake pedal depress amount, and brake pedal depress force. Threshold setting unit 18 sets only one drive-switch threshold if, for example, only one type of actuation input is used to switch the vehicle from automatic to manual driving.

[0056] For example, the threshold setting unit 18 sets a steering angle threshold as the driving mode switching threshold corresponding to the steering wheel angle. For example, the threshold setting unit 18 sets a steering torque threshold as the driving mode switching threshold corresponding to the steering wheel torque. For example, the threshold setting unit 18 sets a threshold for the accelerator pedal depressor magnitude as the driving mode switching threshold corresponding to the accelerator pedal depressor amount. For example, the threshold setting unit 18 sets a threshold for the accelerator pedal depressor force as the driving mode switching threshold corresponding to the accelerator pedal depressor force. For example, the threshold setting unit 18 sets a threshold for the brake pedal depressor amount as the driving mode switching threshold corresponding to the brake pedal depressor amount.For example, the threshold setting unit 18 sets a brake pedal depressor force threshold as the drive-by threshold corresponding to the brake pedal depressor force. The drive-by threshold in the description below also corresponds to the six thresholds described above.

[0057] In a case where the driver state detection unit 17 determines that the driver is in a state in which manual driving can be initiated, the threshold setting unit 18 sets a first drive-switch threshold as the threshold for switching to manual driving. In a case where the driver state detection unit 17 determines that the driver is not in a state in which manual driving can be initiated, the threshold setting unit 18 sets a second drive-switch threshold, which exceeds the first drive-switch threshold, as the threshold for switching to manual driving. A value exceeding the first drive-switch threshold is set as the second drive-switch threshold.In other words, a driving switchover threshold is set as the second driving switchover threshold at which it is less likely than at the first threshold that it will allow switching to manual driving.

[0058] As the size of the steering wheel input increases, a case may arise where the input size increases when a negative value greater than the driver's manual driving input becomes larger. Examples include a case where the steering wheel angle increases by a negative value. In this case, a value exceeding an absolute value of the first drive-shift threshold is set as an absolute value of the second drive-shift threshold. In other words, setting the value exceeding the first drive-shift threshold as the second drive-shift threshold includes setting the value exceeding the absolute value of the first drive-shift threshold as the absolute value of the second shift threshold.

[0059] Fig. Figure 2 is a diagram illustrating a case where a first drive switchover threshold Th1 and a second drive switchover threshold Th2 are fixed values. In a case where it is determined that the driver is not in a state in which manual driving can be triggered, the threshold setting unit 18 sets the threshold for switching to manual driving as shown in Fig. Figure 2 illustrates the second drive-switching threshold Th2, which exceeds the first drive-switching threshold Th1, corresponding to a case where it is determined that the driver is in a state where manual driving can be initiated. This first drive-switching threshold Th1 and the second drive-switching threshold Th2 are each defined, for example, as thresholds for the previously described steering angle threshold, steering torque threshold, accelerator pedal depressor threshold, accelerator pedal depressor force threshold, brake depressor threshold, and brake depressor force threshold.

[0060] In Fig. 1. The threshold setting unit 18 can use the first drive-to-manual switching threshold as an initial setting. In this case, the threshold setting unit 18 changes the threshold for switching to manual driving from the first drive-to-manual switching threshold, which is the initial setting, to the second drive-to-manual switching threshold when the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be triggered. Alternatively, the threshold setting unit 18 can use the second drive-to-manual switching threshold as the initial setting.In this case, the threshold setting unit 18 changes the threshold for manual drive switching from the second drive switching threshold, which is the original setting, to the first drive switching threshold when the driver state determination unit 17 determines that the driver is in a state in which manual driving can be triggered.

[0061] The first driving changeover threshold Th1 and the second driving changeover threshold Th2 are not limited to the specified values ​​and can be variable values. Fig. Figure 3 is a diagram illustrating a change in the driving switchover threshold as a function of the length of time elapsed since the activation of the vehicle's internal instrument. The audio system, the air conditioning, the navigation system 6, the HMI 7, and the like correspond to examples of the vehicle's internal instrument. The vertical axis represents the threshold, and the horizontal axis represents the time elapsed since the activation of the vehicle's internal instrument ceased. Initially, the driver state determination unit 17 determines, as shown in Fig. Figure 3 illustrates that the driver is not in a state where manual driving can be initiated until, for example, a predefined waiting period such as 1.0 second has elapsed since the vehicle's internal instrument was last operated. If the predefined waiting period has elapsed since the vehicle's internal instrument was last operated, the driver state determination unit 17 determines, for example, that the driver is in a state where manual driving can be initiated.

[0062] In Fig. In this case, the second drive-switching threshold Th2 is a fixed value, and the first drive-switching threshold Th1 is a variable value. The first drive-switching threshold Th1 changes within a range that is shorter than the second drive-switching threshold Th2. The threshold setting unit 18 adjusts the first drive-switching threshold Th1 according to the time elapsed since the vehicle's internal instrument was last actuated. The threshold setting unit 18 sets the first drive-switching threshold Th1 so that it decreases as the elapsed time increases, until, for example, the elapsed time reaches a predefined stabilization time such as 3.0 seconds. In a case where the elapsed time exceeds the predefined stabilization time, the threshold setting unit 18 sets the first drive-switching threshold Th1 to a predefined fixed value Thz.Note that both the first driving changeover threshold Th1 and the second driving changeover threshold Th2 can be values ​​that change.

[0063] The driving switch unit 19 in Fig. 1 performs a driving switchover processing. In other words, the driving switchover unit 19 determines whether the magnitude of the manual driving input by the driver exceeds the driving switchover threshold during automatic driving control and performs processing for switching from automatic driving to manual driving in a case where the input magnitude exceeds the driving switchover threshold. In other words, the driving switchover unit 19 performs the processing for switching from automatic driving to manual driving in a case where the input magnitude exceeds the first driving switchover threshold, because the first driving switchover threshold is defined as the driving switchover threshold in a case where the driver is in a state where manual driving can be triggered.Because the second drive switch threshold is defined as the drive switch threshold in a case where the driver is not in a state where manual driving can be initiated, the drive switch unit 19 performs the processing to switch from automatic driving to manual driving in a case where the actuation input variable exceeds the second drive switch threshold. Furthermore, the drive switch unit 19 can perform the processing for switching from automatic driving to manual driving if at least one of the multiple types of actuation input variables exceeds the drive switch threshold in a case where the multiple types of actuation input variables are used to switch the vehicle from automatic driving to manual driving.For example, the drive switching unit 19 can perform the processing for switching to manual driving if one of the actuation input variables exceeds the drive switching threshold, or it can perform the processing for switching to manual driving if two or more types of actuation input variables exceed the drive switching threshold. The drive switching unit 19 outputs a control signal to the drive control unit 15 regarding the termination of automatic drive control. Automatic drive control is then terminated, and the switch from automatic to manual driving is executed. Furthermore, as part of the drive switching processing, the drive switching unit 19 can, for example, set a manual driving flag or a manual driving flag and reset an automatic driving flag. It is then recognized that the switch from automatic to manual driving is being performed by the ECU 10.

[0064] Alternatively, the driving switch unit 19 can perform the processing for switching from automatic to manual driving if, in a case where the magnitude of the manual driving input by the driver exceeds the driving switch threshold, a duration exceeds a duration threshold, which is the length of time during which the actuation input magnitude exceeds the driving switch threshold. The duration threshold is provided, for example, for each type of actuation input magnitude used for switching the vehicle from automatic to manual driving.

[0065] In this case, the threshold setting unit 18, for example, sets a steering angle time threshold as the continuous threshold corresponding to the steering angle of the steering wheel. For example, the threshold setting unit 18 sets a steering torque time threshold as the continuous threshold corresponding to the steering torque of the steering wheel. For example, the threshold setting unit 18 sets an accelerator pedal depressor time threshold as the continuous threshold corresponding to the accelerator pedal depressor amount. For example, the threshold setting unit 18 sets an accelerator pedal depressor force time threshold as the continuous threshold corresponding to the accelerator pedal depressor force. For example, the threshold setting unit 18 sets a brake depressor time threshold as the continuous threshold with respect to the brake pedal depressor amount.For example, the threshold setting unit 18 sets a brake depressor force time threshold as the continuous threshold corresponding to the brake pedal depressor force. The continuous threshold described below also corresponds to the six thresholds described above.

[0066] The following description refers to the aspect in which the processing for switching from automatic to manual driving is performed in a case where the duration for which the input variable exceeds the drive switchover threshold exceeds the duration threshold, and the magnitude of the input variable from the driver exceeds the drive switchover threshold. In a case where the driver state determination unit 17 determines that the driver is in a state in which manual driving can be triggered, the threshold setting unit 18 sets an initial duration threshold as the duration threshold for switching to manual driving.In the event that the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be initiated, the threshold setting unit 18 sets a second duration threshold that exceeds the first duration threshold. In a case where it is determined that the driver is not in a state in which manual driving can be initiated, the threshold setting unit 18 sets the duration threshold to make switching to manual driving less likely.

[0067] Threshold setting 18 can use the first continuous threshold as an initial setting. In this case, threshold setting 18 changes the threshold for switching to manual driving from the first continuous threshold, which is the initial setting, to the second continuous threshold when the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be triggered. Alternatively, threshold setting unit 18 can use the second continuous threshold as the initial setting. In this case, threshold setting unit 18 changes the threshold for switching to manual driving from the second continuous threshold, which is the initial setting, to the first continuous threshold when the driver state determination unit 17 determines that the driver is in a state in which manual driving can be triggered.

[0068] The unit 11 for external situation detection, the vehicle position detection unit 12, the driving condition detection unit 13, the timetable generation unit 14, the driving control unit 15, the actuation input parameter detection unit 16, the driver condition determination unit 17, the threshold setting unit 18, and the driving changeover unit 19, as described above, can be integrated into the ECU 10 by reading software or programs that implement the respective functions. Additionally, some or all of these can be implemented as separate electronic control units. Furthermore, the threshold setting unit 18 is optional.In this case, the driving switch unit 19 performs the switch to manual driving using the first driving switch threshold in a case where the driver state determination unit 17 determines that the driver is in the state in which manual driving can be triggered, and performs the switch to manual driving using the second driving switch threshold in a case where the driver state determination unit 17 determines that the driver is not in the state in which manual driving can be triggered.

[0069] The following describes the operation of the automatic driving system 1 according to this embodiment.

[0070] Fig. Figure 4 is a flowchart illustrating an overview of the automatic driving control processing of the automatic driving system 1 according to this embodiment. Automatic driving control processing is a process for performing automatic driving control for the vehicle. For example, automatic driving control processing is triggered by a triggering process for the automatic driving control and is executed by the ECU 10.

[0071] Sensor information reading processing is first carried out as in step S10 in Fig. Figure 4 illustrates this process. This processing involves reading information from the external sensor 2, the GPS receiver 3, the internal sensor 4, and the map database 5. For example, the external situation detection unit 11 reads the information detected by the external sensor 2 and determines the road width, road shape, the driving situation of another vehicle near the vehicle, the presence of obstacles near the vehicle, and similar information based on the data received from the external sensor 2. Additionally, the vehicle position detection unit 12 reads the vehicle's position information received from the GPS receiver 3 and the map information from the map database 5, and determines the vehicle's position on the map.In addition, the driving condition recognition unit 13 reads the information acquired by the interior sensor 4 and recognizes the driving condition of the vehicle itself based on this acquired information. The vehicle's driving condition includes, for example, its speed, acceleration, and yaw rate.

[0072] The processing then proceeds to step S12, where course generation processing is performed. Course generation processing is used to generate the vehicle's course. For example, the timetable generation unit 14 generates a target course for the vehicle based on the external situation around the vehicle, such as the planned route calculated by the navigation system 6, the vehicle position detected by the vehicle position detection unit 12, the shape of the track, and the presence or absence of an obstacle detected by the external situation detection unit 11. At this time, the course is generated such that the vehicle moves along the track if there is no obstacle in front of it, and the vehicle's course is generated to avoid contact with the obstacle if the obstacle is present.

[0073] The processing then continues to step S14, where a vehicle control processing operation is performed. This operation is used to execute the automatic vehicle control for driving the vehicle along the course generated in step S12. For example, the vehicle control unit 15 outputs a control signal to the actuator 8. Actuation of the actuator 8 then triggers a steering, driving, or braking operation, which is executed for the vehicle, and the vehicle is automatically guided along the target course.

[0074] The processing then proceeds to step S16, where it is determined whether or not to terminate automatic driving control. For example, the driving control unit 15 terminates automatic driving control if a control termination condition is met and continues automatic driving control if the control termination condition is not met. A control termination operation performed by the driver, the vehicle reaching a control endpoint, the presence of manual driving input exceeding the driving switchover threshold, and the like correspond to the control termination condition. The processing returns to step S10 if step S16 determines that automatic driving control should not be terminated. In contrast, a sequence of control processing that occurs in Fig. 4 illustrates a case in which, in step S16, it is determined that the automatic driving control is to be terminated.

[0075] Fig. Figure 5 is a flowchart illustrating the driving switchover processing of the automatic driving system 1 according to this embodiment. The driving switchover processing is a process for performing the driving switchover from automatic driving to manual driving in a case where the manual driving input exceeds the driving switchover threshold during the vehicle's automatic driving control. This driving switchover processing is executed, for example, by the ECU 10 and is triggered simultaneously with the activation of the automatic driving control. The driving switchover processing is performed repeatedly during the automatic driving control and is terminated together with the termination of the automatic driving control.

[0076] First, as in step S20, in Fig. Figure 5 illustrates a threshold setting process. The threshold setting process is a process for setting the drive-to-drive threshold. During this threshold setting process, the threshold setting unit 18 sets the first drive-to-drive threshold as the threshold for switching to manual driving in a case where the driver state determination unit 17 determines that the driver is in a state in which manual driving can be triggered. In a case where the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be triggered, the threshold setting unit 18 sets the second drive-to-drive threshold, which is higher than the first drive-to-drive threshold, as the threshold for switching to manual driving.

[0077] The processing then proceeds to step S22, where an actuation input size acquisition process is performed. This process captures the magnitude of manual driving input. Steering wheel operation, accelerator pedal operation, brake pedal operation, and the like correspond to manual driving input. During this actuation size acquisition process, the actuation input size acquisition unit 16 captures the magnitudes of the steering wheel, accelerator pedal, and brake pedal inputs made by the driver for the vehicle, based, for example, on the acquisition result from the interior sensor 4.

[0078] The processing then proceeds to step S24, where the drive switching unit 19 determines whether the actuation input variable, which is captured in the actuation input variable acquisition processing, exceeds the drive switching threshold. This determination processing in step S24 can be performed with reference to the steering wheel angle, steering wheel torque, accelerator pedal depressor magnitude or travel, accelerator pedal depressor force, brake pedal depressor magnitude, or brake pedal depressor force. In some cases, however, this determination processing in step S24 is performed with reference to a combination of the steering wheel angle, steering wheel torque, accelerator pedal depressor magnitude, accelerator pedal depressor force, brake pedal depressor magnitude, and brake pedal depressor force.Furthermore, in the determination processing in step S24, the question of whether the duration exceeds the duration threshold, which is the length of time during which the actuation input size exceeds the driving switchover threshold, can be used as the determination of whether the size of the manual driving actuation input by the driver exceeds the driving switchover threshold or not.

[0079] In a case where, as a result of the determination processing in step S24, it is determined that the actuation input value exceeds the drive switchover threshold, the switchover from automatic to manual driving is performed by the drive switch unit 19 in step S26. For example, the drive switch unit 19 outputs the control signal regarding the termination of automatic drive control to the drive control unit 15. In this case, automatic drive control is terminated when the automatic drive control termination condition in step S16 is met. Fig. 4 is fulfilled. This triggers the switch from automatic to manual driving. After the processing in step S28 is complete, a Fig. 5. Illustrated sequence of tax processing completed.

[0080] In a case where, as a result of the determination processing in step S24, it is determined that the actuation input value does not exceed the drive switching threshold, the drive control unit 15 proceeds to execute automatic drive control in step S28. In this case, the drive switching unit 19 determines that manual drive actuation will not be performed, or that manual drive actuation will not be performed up to the point of drive switching execution, and proceeds with automatic drive control. After the processing of step S28, a sequence of the following occurs: Fig. The 5 illustrated tax processing steps have been completed.

[0081] Following this driving switch processing, the driving switch from automatic driving to manual driving can be performed in a case where the magnitude of the manual driving input exceeds the driving switch threshold during automatic driving control for the vehicle. In a case where the driver is not in a state in which manual driving can be triggered at that time, the driving switch threshold is set to a higher value than in a case where the driver is in a state in which manual driving can be triggered, thus making the switch to manual driving less likely.Accordingly, in a case where the driver is not in a state in which manual driving can be triggered, a simple switch to manual driving is prevented even if a driving operation input variable is present, and thus an inappropriate switch to manual driving can be suppressed.

[0082] Fig. Figure 6 is a flowchart illustrating the threshold setting process of the automatic driving system 1 according to this embodiment. The in Fig. Figure 6 illustrates threshold setting processing, showing a specific example of threshold setting processing in the context of Fig. Step S20 was illustrated in section 5 and is a function as a subroutine of the threshold setting processing in step S20.

[0083] Driver state detection processing is first performed as in step S30 in Fig. Figure 6 illustrates this process. Driver state detection processing is a procedure to detect whether the vehicle's driver is in a state where manual driving can be initiated. For example, the driver state detection unit 17 detects the driver's state based on the detection result from the contact sensor 91, which is integrated into the steering wheel. In this case, the driver state detection unit 17 can detect, based on an output signal from the contact sensor 91, whether the driver is in contact with the steering wheel or not. If the driver is in contact with the steering wheel, the driver state detection unit 17 recognizes that the driver is in a state where manual driving can be initiated.The driver state determination unit 17 detects that in a case where the driver is not touching the steering wheel, the driver is not in a state in which manual driving can be triggered.

[0084] The driver's condition can also be detected based on the image captured by the driver detection camera 92 in the driver condition detection processing unit. In other words, the driver condition detection unit 17 can detect, based on the image captured by the driver detection camera 92, whether the driver is in a state in which manual driving can be triggered. For example, the driver condition detection unit 17 detects the driver's posture by processing the image captured by the driver detection camera 92. Furthermore, the driver condition detection unit 17 can detect the orientation of the driver's face or the direction of the driver's gaze based on the image captured by the driver image camera 92. Additionally, the driver condition detection unit 17 can detect the open state of the driver's eyelids based on the image captured by the driver detection camera 92.

[0085] Furthermore, the driver's state can also be determined based on the activation signal of the instrument in the vehicle, such as the HMI 7, within the driver state detection processing unit. In other words, the driver state detection unit 17 can determine, based on the activation signal of the instrument in the vehicle, whether the driver is in a state in which manual driving can be initiated. For example, the driver state detection unit 17 can determine that the driver is not in a state in which manual driving can be initiated if the driver is operating the vehicle's instrument, or if a predefined time period, such as 1.0 second, must elapse after the driver has been operating the vehicle's instrument.

[0086] Furthermore, the driver's state can also be determined in the driver state detection processing unit based on the data from the biometric information sensor 93, such as brainwave and pulse measurements. In other words, the driver state detection unit 17 can determine, based on a data from the biometric information sensor 93, whether the driver is in a state in which manual driving can be initiated. For example, if the driver is awake, the driver state detection unit 17 can determine that the driver is in a state in which manual driving can be initiated, and if the driver is unconscious, it can determine that the driver is not in a state in which manual driving can be initiated.

[0087] In the driver state detection processing in step S30, detection can be performed with reference to all detection results from the contact sensor 91, the image captured by the driver imaging camera 92, the result of the activation of the vehicle's internal instrument, and the detection result from the biometric information sensor 93. However, the driver state can also be detected using only some of these.

[0088] The processing then proceeds to step S32, where it is determined whether the driver is in a state where manual driving can be initiated. This determination processing is based on the driver's state, obtained in the driver state acquisition processing in step S30, to ascertain whether the driver is in a state where manual driving can be initiated.

[0089] For example, the driver state determination unit 17 determines, based on the detection result of the contact sensor 91, whether the driver is in a state in which manual driving can be initiated. In other words, if the driver is touching the steering wheel, the driver state determination unit 17 determines that the driver is in a state in which manual driving can be initiated, and if the driver is not touching the steering wheel, it determines that the driver is not in a state in which manual driving can be initiated.

[0090] Furthermore, the driver state determination unit 17 can determine, based on the image captured by the driver detection camera 92, whether the driver is in a state in which manual driving can be initiated. In other words, if the driver's posture is a predefined driving posture, the driver state determination unit 17 determines that the driver is in a state in which manual driving can be initiated. Conversely, if the driver's posture is a predefined non-driving posture (such as the posture with the neck tilted to operate the portable information terminal and the posture on the tilted backrest of the driver's seat), the driver state determination unit 17 determines that the driver is not in a state in which manual driving can be initiated.Furthermore, the driver state detection unit 17 can determine that the driver is in a state where manual driving can be initiated if the driver's face or gaze is directed towards the front of the vehicle, and can determine that the driver is not in a state where manual driving can be initiated if the driver's face or gaze is not directed towards the front of the vehicle. Additionally, the driver state detection unit 17 can determine that the driver is in a state where manual driving can be initiated if the driver's eyelids are open, and can determine that the driver is not in a state where manual driving can be initiated if the driver's eyelids are closed.When determining the driver's condition based on the image captured by the driver imaging camera 92, the determination can be made based on all points relating to the driver's posture, facial orientation, gaze direction, and eyelid position. The determination can also be made based on individual points.

[0091] Furthermore, the driver state determination unit 17 can determine, based on the activation signal from the vehicle's internal instrument such as the HMI 7, whether the driver is in a state where manual driving can be initiated. In other words, the driver state determination unit 17 determines that the driver is not in a state where manual driving can be initiated if the driver is operating the vehicle's internal instrument, and determines that the driver is in a state where manual driving can be initiated if the driver is not operating the vehicle's internal instrument.In this case, the driver state determination unit 17 can determine that the driver is not in a state in which manual driving can be triggered if the predetermined time period, such as 1.0 seconds, has yet to elapse after the driver has finished operating the vehicle's instrument, and can determine that the driver is in a state in which manual driving can be triggered if the predetermined time period has elapsed since the driver finished operating the vehicle's instrument.

[0092] Furthermore, the driver state determination unit 17 can determine, based on the acquisition result of the biometric information sensor 93, whether or not the driver is in a state in which manual driving can be triggered. In other words, the driver state determination unit 17 can determine that the driver is not in a state in which manual driving can be triggered if the driver is unconscious or distracted, with examples including a case in which attention is less than the predefined threshold, and can determine that the driver is in a state in which manual driving can be triggered if the driver is awake, with examples including a case in which alertness exceeds the predefined threshold.

[0093] In a case where step S32 determines that the driver is in a state where manual driving can be initiated, the threshold setting unit 18 sets the first drive switch threshold as the drive switch threshold in step S34. In a case where step S32 determines that the driver is not in a state where manual driving can be initiated, the threshold setting unit 18 sets the second drive switch threshold as the drive switch threshold in step S36. The processing of step S34 and the processing of step S36 are each performed with respect to, for example, the steering angle threshold, the steering torque threshold, the accelerator pedal depress threshold, the accelerator pedal depress threshold, the brake pedal depress threshold, and the brake pedal depress threshold.Because the value exceeding the first drive switch threshold is set as the second drive switch threshold, in a case where the driver is not in a state where manual driving can be triggered, the drive switch threshold that causes the switch to manual driving is set so that the switch is less likely than in a case where the driver is in a state where manual driving can be triggered. After the processing of step S24 and the processing of step S36 are complete, a sequence of control processing as in . Fig. 6 illustrated completed.

[0094] Following this threshold setting process, the drive switchover threshold is adjusted so that switching to manual driving is less likely to occur in a case where the driver is determined not to be in a state in which manual driving can be triggered, than in a case where the driver is determined to be in a state in which manual driving can be triggered. If the driver is not in a state in which manual driving can be triggered, switching to manual driving via the manual drive input is permitted to occur less frequently than if the driver is in a state in which manual driving can be triggered.

[0095] Fig. Figure 7 is a flowchart showing an example of the threshold setting processing of the automatic driving system 1 according to this embodiment. Fig. Figure 8 is a flowchart showing another example of the threshold setting processing of the automatic driving system 1 according to this embodiment.

[0096] The threshold setting processing, which is in Fig. Figure 7 illustrates a processing step for setting the drive switchover threshold by determining, based on whether the driver is touching the steering wheel or not, whether the driver is in a state where manual drive operation is permitted. The threshold setting processing shown in Fig. As illustrated in 7, the following is shown: Fig. Figure 6 illustrates the threshold setting process in more detail. This threshold setting process is initiated, for example, together with the initiation of the automatic driving control and is executed by ECU 10.

[0097] According to Fig. In step S40, the driver state determination unit 17 first receives an output value Psensor from contact sensor 91 and then determines in step S42 whether the output value Psensor exceeds a predefined threshold value Pthre. If step S42 determines that the output value Psensor exceeds the threshold value Pthre, the driver state determination unit 17 resets the steering wheel release duration tcount1 and sets it to 0 in step S44. If step S42 determines that the output value Psensor does not exceed the threshold value Pthre, the driver state determination unit 17 sets a value for the steering wheel release duration tcount1 in step S46. This value is obtained by adding a cycle time tcycle1 to a previous value of the steering wheel release duration tcount1. The cycle time tcycle1 is a processing cycle time appropriate for the threshold setting process, which is defined in Fig. Figure 7 illustrates this. Then, in step S48, the driver state determination unit 17 determines whether the steering wheel release duration tcount1 exceeds a predefined threshold value Tthre1. If step S48 determines that the steering wheel release duration tcount1 exceeds the threshold value Tthre1, the threshold setting unit 18 sets the second drive switchover threshold as the drive switchover threshold in step S50. If step S48 determines that the steering wheel release duration tcount1 does not exceed the threshold value Tthre1, the threshold setting unit 18 sets the first drive switchover threshold as the drive switchover threshold in step S52. After the processing of steps S50 and S52 is complete, a sequence of the steps described in Figure 7 is executed. Fig. 7 illustrated tax processing completed.

[0098] After the in Fig. The threshold setting process illustrated in section 7 allows the determination of whether the driver is in a state where manual driving can be triggered, based on whether the steering wheel is released by the driver for a period longer than a predefined time, such as the time equal to the threshold Tthre1. Accordingly, it can be easily and accurately determined, using contact sensor 91, whether the driver is in a state where manual driving can be triggered during the setting of the driving switch point value.

[0099] The threshold setting processing, which is in Fig. Figure 8 illustrates a processing method for setting the drive switchover threshold by determining, based on the time elapsed since the driver ceased operating the vehicle's internal instrument, whether the driver is in a state where manual driving can be initiated. The [method] in Fig. 8 illustrated threshold value setting processing shows the in Fig. Figure 6 illustrates the threshold setting processing in more detail. The vehicle's in-vehicle instrument is an instrument that the driver can operate; examples include a navigation device, the audio system, and an air conditioning system. This threshold setting processing is triggered, for example, together with the activation of the automatic driving control and is executed by ECU 10.

[0100] After Fig. In step S60, the driver state determination unit 17 first receives a signal regarding the activation or non-activation of the vehicle's internal instrument and determines in step S62 whether the internal instrument has been activated or not. If step S62 determines that the internal instrument has been activated, the driver state determination unit 17 resets the elapsed time tcount2 from the time of activation and sets it to 0 in step S64. If step S62 determines that the internal instrument has not been activated, the driver state determination unit 17 sets the elapsed time tcount2 to a value obtained by adding a cycle time Tcycle2 to a previous value of the elapsed time tcount2 in step S66. The cycle time Tcycle2 is a processing cycle time suitable for threshold setting processing.Then, in step S68, the driver state determination unit 17 determines whether the elapsed time tcount2 exceeds a predefined threshold Tthre2. If step S68 determines that the elapsed time tcount2 exceeds the threshold Thre2, the threshold setting unit 18 sets the first drive switch threshold in step S70 as the drive switch threshold. If step S68 determines that the elapsed time tcount2 does not exceed the threshold Tthre2, the threshold setting unit 18 sets the second drive switch threshold in step S72 as the drive switch threshold. After the processing of steps S70 and S72 is complete, a sequence of events is initiated. Fig. 8 illustrated tax processing completed.

[0101] After the in Fig.The driver state detection processing illustrated in Figure 8 can determine, based on whether a predefined time, such as the time equal to the threshold Tthre2, has elapsed since the time the driver activated the vehicle's internal instrument, whether the driver is in a state in which manual driving can be triggered, and the drive switchover threshold can be set according to the state in which manual driving can be triggered.

[0102] As described above, according to the automatic driving system 1 of this embodiment, switching to manual driving is carried out when the magnitude of the manual driving input exceeds the first driving switchover threshold in a case where it is determined that the driver is in a state in which manual driving can be triggered, and switching to manual driving is carried out when the magnitude of the manual driving input exceeds the second driving switchover threshold, which is greater than the first driving switchover threshold, in a case where it is determined that the driver is not in a state in which manual driving can be triggered during automatic driving control for the vehicle.In other words, switching to manual driving is performed using the drive switchover threshold, which makes switching to manual driving less likely than if the driver were in a state where manual driving could be initiated, if it is determined that the driver is not in a state where manual driving could be initiated during automatic driving control. Accordingly, switching to manual driving is prevented compared to when the driver is in a state where manual driving could be initiated, as would be the case if the driver were in a state where manual driving could be initiated during automatic driving control. Consequently, the automatic driving system can suppress inappropriate switching to manual driving that the driver does not intend.

[0103] Furthermore, in the automatic driving system 1 according to this embodiment, the detection result of the contact sensor 91, which can detect whether the driver is touching the steering wheel or not, determines whether the driver is in a state in which manual driving can be initiated. Accordingly, it can be precisely determined whether the driver is in a state in which manual driving can be initiated. In other words, if the driver is touching the steering wheel, it is more likely that the driver is assuming a driving position and the preparation for driving is permitted; thus, a precise determination of whether the driver is in a state in which manual driving can be initiated can be made based on whether the driver is touching the steering wheel or not.

[0104] In summary, the invention discloses an automatic driving system 1 comprising the following: An actuation input quantity detection unit 16, configured to detect a driving actuation input quantity by a driver during automatic driving control for a vehicle; a driver state determination unit 17, configured to determine whether the driver is capable of initiating manual driving during automatic driving control for the vehicle; a driving switchover unit 19, configured to perform a switchover from automatic driving to manual driving based on the result of a comparison between the driving actuation input quantity and a driving switchover threshold, which is a threshold for switching from automatic driving to manual driving;and a threshold setting unit 18 configured to set the drive-switch threshold to a first drive-switch threshold when the driver state determination unit determines that the driver is capable of starting manual driving, and to set the drive-switch threshold to a second drive-switch threshold exceeding the first drive-switch threshold when the driver state determination unit determines that the driver is not capable of starting manual driving.

Claims

[1] An automated driving system (1) comprising: an actuation input quantity detection unit (16) designed to detect a driving actuation input quantity by a driver during automatic driving control for a vehicle; a driver state determination unit (17) designed to determine whether the driver is capable of initiating manual driving during automatic driving control for the vehicle; a driving switching unit (19) designed to perform a switch from automatic driving to manual driving based on the result of a comparison between the driving operation input variable and a driving switching threshold value, which is a threshold for switching from automatic driving to manual driving; and characterized by a threshold setting unit (18) designed to to set the drive switchover threshold to a first drive switchover threshold when the driver state determination unit determines that the driver is in a state where manual driving can be initiated, and to set the drive-to-drive threshold to a second drive-to-drive threshold that exceeds the first drive-to-drive threshold if the driver state determination unit determines that the driver is not in a state in which manual driving can be initiated. [2] Automatic driving system according to claim 1, wherein the driving switching unit is configured to perform the switching from automatic driving to manual driving when the driving operation input variable exceeds the driving switching threshold. [3] Automatic driving system according to claim 1 or 2, further comprising: a contact sensor (91) designed to detect when the driver touches the vehicle's steering wheel, the driver state determination unit is designed to determine, based on the result of the detection by the contact sensor, whether the driver is in a state in which manual driving can be started or not. [4] Automatic driving system according to claim 1 or 2, further comprising: a biometric information sensor (93) designed to capture biometric information of the driver, the driving state determination unit is designed to determine, based on a result of the recording by the biometric information sensor, whether the driver is in a state in which manual driving can be started or not. [5] Automatic driving system according to claim 1 or 2, further comprising an in-vehicle instrument (7), wherein the driving state determination unit is designed to determine, based on whether an actuation signal from the in-vehicle instrument is read or not, whether the driver is in the state in which manual driving can be started or not. [6] Automatic driving system according to claim 1 or 2, further comprising: a camera (92) designed to image the driver, the driving state determination unit is designed to determine, on the basis of an image of the driver taken by the camera, whether the driver is in a state in which manual driving can be started or not. [7] Automatic driving system according to claim 6, wherein the driving state determination unit is designed to determine, on the basis of at least either the driver's posture, the direction of the face or the direction of the driver's gaze, or the size of the driver's eye opening from the image of the driver taken by the camera, whether the driver is in the state in which manual driving can be started or not.

Images