autonomous driving system

Abstract

System (100) for autonomous driving, which is mounted on a vehicle (1), comprising: a necessary information acquisition unit (121) which periodically acquires necessary information (90) which is required to calculate a target path (TP); a target path determination unit (122) which determines the target path (TP) based on the necessary information (90);and a vehicle driving control unit (126) which performs vehicle driving control that controls a journey of the vehicle (1) to follow the target path (TP), wherein a vehicle coordinate system corresponds to a relative coordinate system defined at the vehicle (1), a first time point (T1) corresponds to a time point at which the acquisition unit (121) obtains the necessary information (90), a first coordinate system corresponds to the vehicle coordinate system at the first time point (T1), a second coordinate system corresponds to the vehicle coordinate system at a second time point (T2) which is later than the first time point (T1), the target path determination unit (122) comprises: a target path calculation unit (123) which calculates a first target path (TP1) defined in the first coordinate system based on the necessary information (90) obtained at the first time point (T1);and a target path correction unit (124) which corrects the first target path (TP1) to a second target path (TP2) defined in the second coordinate system by performing a coordinate transformation from the first coordinate system to the second coordinate system, and the vehicle driving control unit (126) uses the second target path (TP2) as the target path (TP) to perform vehicle driving control.

Description

Background Technical field

[0001] The present disclosure relates to an autonomous driving system. In particular, the present disclosure relates to an autonomous driving system that controls the journey of a vehicle so that it follows a target path. General state of the art

[0002] Patent literature 1 discloses a vehicle driving assistance device that assists a vehicle's movement. The vehicle driving assistance device calculates a control command value for driving around an obstacle based on a vehicle motion state and an obstacle state, which are detected by sensors. In particular, the vehicle driving assistance device calculates both a first control command value with low precision and a second control command value with high precision. The time required to calculate the second control command value with high precision is longer than the time required to calculate the first control command value with low precision. That is, a calculation delay occurs when the second control command value is calculated.To compensate for such a calculation delay, the vehicle assistance device uses the vehicle motion state and obstacle state detected by the sensors to "predict" a future vehicle motion state and obstacle state that will occur a calculated time delay later. The vehicle assistance device then calculates the second control command value with high precision based on the predicted future vehicle motion state and obstacle state.

[0003] Patent literature 2 discloses a system for autonomous driving. The autonomous driving system comprises: an environmental information acquisition unit, which acquires environmental information about a vehicle; a route generation unit, which generates a route plan for the vehicle based on the acquired environmental information and map information; and a driving control unit, which autonomously controls the vehicle's journey according to the generated route plan. List of the relevant state of the art Patent literature 1: Japanese patent publication number JP 2010-173616 A Patent literature 2: Japanese patent publication number JP 2016-099713 A Summary

[0004] The following section examines "path following control" as implemented by an autonomous driving system. With path following control, the autonomous driving system periodically calculates a target path for a vehicle and controls the vehicle's movement so that it follows this path. Path following control can be subject to control delays due to various factors.

[0005] One factor for the control delay corresponds, for example, to the computation time required to calculate the target path. Information necessary for calculating the target path is obtained at a predetermined time, and the calculation of the target path based on this information is completed after that predetermined time. This computation time, required to calculate the target path, causes the control delay.

[0006] The control delay of the path-following control system causes a decrease in its ability to follow the target path. When the path-following performance of the autonomous driving system is reduced, a vehicle occupant may feel anxious and uneasy, leading to a decrease in confidence in the autonomous driving system.

[0007] According to the technology disclosed in the aforementioned patent literature 1, the computation delay is taken into account when calculating the second control command value with high precision. Specifically, the vehicle motion state and obstacle state detected by the sensors are used to "predict" a future vehicle motion state and obstacle state after the computation delay time. The second control command value is then calculated with high precision based on the predicted future vehicle motion state and obstacle state. However, predicting the vehicle motion state and obstacle state requires complex computational processing, which leads to an increase in computational load, computation time, and computational resource.

[0008] One objective of the present disclosure is to provide a technology that can increase the path-following performance of an autonomous driving system that controls the driving of a vehicle so that it follows a target path, while suppressing an increase in computational load.

[0009] A first revelation is a vehicle-mounted system for autonomous driving.

[0010] The autonomous driving system includes: a unit of acquisition for necessary information, which periodically acquires necessary information required to calculate a target path; a target path determination unit that determines the target path based on the necessary information; and a vehicle driving control unit which performs vehicle driving control that controls the vehicle's movement to follow the target path.

[0011] A vehicle coordinate system corresponds to a relative coordinate system defined for the vehicle.

[0012] A first point in time corresponds to a point in time at which the unit obtaining necessary information acquires the necessary information.

[0013] A first coordinate system corresponds to the vehicle coordinate system at the first time point.

[0014] A second coordinate system corresponds to the vehicle coordinate system at a second time point in time, which is later than the first time point in time.

[0015] The target path determination unit includes: a target path calculation unit that calculates a first target path defined in the first coordinate system based on the necessary information obtained at the first time; and a target path correction unit which corrects the first target path to a second target path defined in the second coordinate system by performing a coordinate transformation from the first coordinate system to the second coordinate system.

[0016] The vehicle driving control unit uses the second destination path as the destination path to perform vehicle driving control.

[0017] In addition to the characteristics of the first revelation, a second revelation possesses the following features.

[0018] A delay time from the first time point to the second time point is predetermined.

[0019] A third revelation possesses the following characteristics in addition to those of the first or second revelation.

[0020] A delay time from the first time point to the second time point corresponds to the time required for the destination path calculation unit to calculate the first destination path.

[0021] In addition to the characteristics of the third revelation, a fourth revelation possesses the following features.

[0022] The target path determination unit determines and updates the target path at any time the information acquisition unit obtains the necessary information.

[0023] The target path determination unit determines a new target path such that a specific segment starting from the beginning of the new target path overlaps a previous target path.

[0024] The definite section includes at least one section corresponding to a time period from the first point in time to the second point in time.

[0025] According to the first disclosure, the autonomous driving system performs goal path correction processing in its path following control. Specifically, the autonomous driving system corrects the first goal path defined in the first coordinate system to the second goal path defined in the second coordinate system. The first coordinate system corresponds to the vehicle's coordinate system at the first time when the necessary information is acquired. The second coordinate system corresponds to the vehicle's coordinate system at the second time, which is later than the first time. The effects of control delay are reduced by the goal path correction processing. Therefore, when the second goal path is used to control the vehicle after correction, the control error is smaller and the control accuracy is higher compared to when the first goal path is used.In other words, the system's ability to follow the target path is improved. When the path-following capability of the autonomous driving system is enhanced, the vehicle occupant's feelings of anxiety and unease are reduced, contributing to increased confidence in the autonomous driving system.

[0026] Furthermore, no complex computational processing is required for target path correction. The second target path can be easily obtained by performing a simple coordinate transformation from the first to the second coordinate system. There is no need to predict the information required to obtain the second target path at the second time. Since no complex predictive processing is necessary, an increase in computational load is suppressed. According to the first disclosure, as described above, it is possible to increase path-following performance while suppressing the increase in computational load.

[0027] According to the second disclosure, the delay time from the first time point to the second time point is predetermined. In this case, the target path correction processing is further simplified, which is preferable.

[0028] According to the third disclosure, the delay time from the first time point to the second time point corresponds to the time required for the target path calculation processing. In this case, it is possible to reduce the impact of the control delay caused by the target path calculation time.

[0029] According to the fourth aspect, the new target path is determined such that a specific segment, starting from the beginning of the new target path, overlaps the previous target path. Consequently, the new and previous target paths are seamlessly connected. Therefore, discontinuous changes in vehicle control parameters are suppressed when the target path used for vehicle control is switched. As a result, sudden changes and disturbances in vehicle behavior are prevented. List of characters Fig. Figure 1 is a conceptual illustration to explain path following control by an autonomous driving system according to a first embodiment of the present disclosure; Fig. Figure 2 is a conceptual illustration to explain the vehicle driving control in the first embodiment of the present disclosure; Fig. Figure 3 is a conceptual illustration to explain a control delay due to a target path calculation time in the first embodiment of the present disclosure; Fig. Figure 4 is a conceptual illustration showing a difference in the appearance of a target path between a first coordinate system and a second coordinate system in the first embodiment of the present disclosure; Fig. Figure 5 is a conceptual illustration to explain a target path correction processing in the first embodiment of the present disclosure; Fig. Figure 6 is a conceptual illustration to explain the path following control by the autonomous driving system according to the first embodiment of the present disclosure; Fig. Figure 7 is a block diagram showing a configuration example of the autonomous driving system according to the first embodiment of the present disclosure; Fig. Figure 8 is a block diagram illustrating information acquisition processing by the autonomous driving system according to the first embodiment of the present disclosure; Fig. Figure 9 is a block diagram illustrating control processing for autonomous driving by the autonomous driving system according to the first embodiment of the present disclosure; Fig. Figure 10 is a block diagram showing a functional configuration of a path following control device of the autonomous driving system according to the first embodiment of the present disclosure; Fig. Figure 11 is a flowchart showing the path following control by the path following control device according to the first embodiment of the present disclosure; Fig. Figure 12 is a conceptual illustration to explain an update cycle in a second embodiment of the present disclosure; Fig. Figure 13 is a conceptual illustration to explain a problem to be solved in the second embodiment of the present disclosure; Fig. Figure 14 is a conceptual illustration to explain a target path calculation processing in the second embodiment of the present disclosure; Fig. Figure 15 is a block diagram showing a functional configuration of the path following control device of the autonomous driving system according to the second embodiment of the present disclosure; Fig. Figure 16 is a flowchart showing the path following control by the path following control device according to the second embodiment of the present disclosure; Fig. Figure 17 is a block diagram showing a functional configuration of the path following control device of the autonomous driving system according to a third embodiment of the present disclosure; and Fig. Figure 18 is a flowchart showing the path following control by the path following control device according to the third embodiment of the present disclosure. Designs

[0030] Embodiments of the present disclosure are described below with reference to the accompanying figures. First embodiment Summary of path following control by the autonomous driving system

[0031] Fig. Figure 1 is a conceptual illustration to explain path following control by an autonomous driving system according to the present embodiment. The autonomous driving system is mounted on a vehicle. 1 It assembles and controls autonomous driving of the vehicle. 1 Path following control is a type of control system used for autonomous driving. In path following control, the autonomous driving system periodically calculates a target path. TP for the vehicle 1 and controls the vehicle's movement 1 , so that this corresponds to the final target path TP follows.

[0032] Here, a vehicle coordinate system is used ( X , Y ) defined. The vehicle coordinate system corresponds to one for the vehicle 1 a fixed relative coordinate system, and this varies with the movement of the vehicle. 1This means that the vehicle coordinate system is defined by the vehicle's position and orientation. 1 defined. In the Fig. In example 1, the X-direction corresponds to a forward direction of the vehicle. 1 and the Y-direction corresponds to a plane direction orthogonal to the X-direction. However, the vehicle coordinate system is not based on the one in Fig. The example shown is limited to one.

[0033] Path following control is performed based on the vehicle's coordinate system. This means the autonomous driving system calculates the target path. TP The vehicle coordinate system is periodic. The autonomous driving system then controls the vehicle's movement. 1 , to the final destination path TP to follow. Controlling the vehicle's movement. 1 , to follow the target path TP Following this is referred to below as "vehicle driving control".

[0034] Fig. Figure 2 is a conceptual diagram to explain vehicle driving control. It shows an example of a positional relationship between the vehicle and the vehicle. 1 and the target path TP in the vehicle coordinate system is in Fig. 2 shown. During vehicle control, a deviation of the vehicle is detected. 1 from the target path TP controlled to be reduced, to cause the vehicle 1 the target path TP This follows. For this reason, parameters such as a lateral deviation Ed, an alignment angle difference θd, and a curvature of the target path are used. TP and similar factors are taken into account. The lateral deviation Ed corresponds to a deviation in a Y-direction of the vehicle. 1 from the target path TP The alignment angle difference θd corresponds to a difference in an alignment angle between the vehicle 1 and the target path TP The autonomous driving system can control the vehicle's driving based on the lateral deviation Ed, the orientation angle difference θd, and the curvature of the target path. TP and carry out similar activities.

[0035] The inventors of the present application have identified the following problem with regard to path following control. Specifically, path following control can experience a control delay due to various factors. This control delay results in a decrease in the performance of following the target path. TP , which is not preferable. The various factors contributing to control delay include information communication time, computation processing time, actuator response time, etc. From these factors, a value is derived to calculate the target path. TP required calculation time, that is, a target path calculation time, considered in such a way that it contributes most to the control delay.

[0036] Fig. Figure 3 is a conceptual illustration to explain the control delay due to the target path calculation time. At an initial point in time... T1 The autonomous driving system obtains information that is used to calculate the destination path. TP are necessary. Those required to calculate the target path. TP The necessary information is referred to below as "required information". The autonomous driving system then calculates a new target path based on this required information. TP It takes some time to find the target path. TP to calculate, and therefore the calculation of the target path TP at a second point in time T2 completed, which is later than the first point in time T1lies. A time period starting from the first point in time. T1 up to the second point in time T2 corresponds to the target path calculation time.

[0037] In Fig. 3 corresponds to a first position P1 a position of the vehicle 1 at the first time T1 A second position P2 corresponds to a position of the vehicle 1 at the second point in time T2 A first coordinate system ( X1 , Y1 ) corresponds to the vehicle coordinate system at the first time point T1 , that is, in the first position P1 A second coordinate system ( X2 , Y2 ) corresponds to the vehicle coordinate system at the second time point T2 , that is, in the second position P2The first and second coordinate systems differ from each other by an amount corresponding to the target path calculation time. Therefore, the "appearance" or shape of the target path differs. TP between the first coordinate system and the second coordinate system.

[0038] Fig. Figure 4 shows a difference in the shape of the target path. TP between the first coordinate system and the second coordinate system. In Fig. 4 represents a first target path TP1 the target path TP from the perspective of the first position P1 that is, the target path defined in the first coordinate system TP On the other hand, a second target path represents TP2 the target path TP from the perspective of the second position P2 that is, the target path defined in the second coordinate system TP The first target path TP1 and the second target path TP2 differ from each other by an amount according to the target path calculation time.

[0039] Here the vehicle driving control (see Fig. 2) taken into account by the autonomous driving system. The vehicle driving control is based on a new destination path. TP It can of course be started after the new target path has been determined. TP is determined, that is, according to the second position P2 (the second time point T2 ). If the vehicle's driving control is in the second position P2 This can be carried out using the second target path. TP2 compared to the first target path TP1 Higher control accuracy can be achieved to perform vehicle driving control. However, it is not possible to use the second target path. TP2 to calculate directly from the necessary information. The reason for this is that the necessary information is available at the first position. P1(first point in time T1 ) obtained. Using the information from the first position. P1 The necessary information obtained can only be used to determine the first target path defined in the first coordinate system. TP1 will be calculated.

[0040] If the first target path defined in the first coordinate system TP1 When used to perform vehicle driving control, a control error is observed compared to a case where the second target path defined in the second coordinate system is used. TP2 The larger the area used, the lower the control accuracy. In other words, the performance for following the target path decreases. TP is reduced. If the path-following capability of the autonomous driving system is reduced, an occupant of the vehicle will feel... 1 anxious and peculiar, leading to a decrease in trust in the autonomous driving system.

[0041] In light of the foregoing, the autonomous driving system according to the present embodiment performs the “goal path correction processing”, which corrects the first goal path TP1 on the second target path TP2 corrected. Fig. Figure 5 is a conceptual illustration to explain the target path correction processing in the present embodiment. As described above, the first target path defined in the first coordinate system is TP1 from those in first position P1 (first point in time T1 The necessary information obtained is calculated. During the goal path correction processing for the autonomous driving system, a "coordinate transformation" is performed from the first coordinate system to the second coordinate system in order to determine the first goal path. TP1 on the second target path TP2 to correct (convert). No complicated calculations are needed for the coordinate transformation, and it is possible to use the second target path. TP2 to obtain in a simple way.

[0042] Fig. Figure 6 shows the path following control by the autonomous driving system according to the present embodiment in a summarized manner. At the first time point T1 (that is, the first position) P1 The autonomous driving system obtains the necessary information. The autonomous driving system then concludes at that point. T2 (that is, the second position) P2 ) the calculation of the target path TP based on the necessary information at the first position P1 , that is, the first target path TP1 Furthermore, the autonomous driving system performs destination path correction processing to correct the calculated initial destination path. TP1 on the second target path TP2 to correct this. Then the autonomous driving system uses the second destination path. TP2 as the target path TP , in order to perform vehicle driving control, so that the vehicle 1 the second target path TP2 follows. Effects

[0043] As described above, the autonomous driving system according to the present embodiment performs the target path correction processing in the path following control. In particular, the autonomous driving system corrects the target path defined in the first coordinate system. TP1 on the second target path defined in the second coordinate system TP2 The influence of the control delay is reduced by the goal path correction processing. Therefore, if the second goal path TP2 after the correction is used to perform vehicle driving control, the control error compared to the case in which the first target path TP1 The smaller the size used, the higher the control accuracy. In other words, the performance for following the target path improves. TP is increased. When the path-following capability of the autonomous driving system is increased, the sensations of the vehicle occupant are reduced. 1 It reduces anxiety and strangeness, which contributes to an increase in trust in the autonomous driving system.

[0044] It should be noted that in the Fig. 3 to Fig. In the example shown in Figure 6, the target path calculation time is considered a representative factor for the control delay. However, the present embodiment is not limited to this. For example, the control delay can be taken into account due to another factor (the information communication time, the actuator response time, etc.). Alternatively, a portion of the target path calculation time can be considered. In general, it is sufficient that the second time point T2 at a time corresponding to at least part of the control delay starting from the first point in time T1 is delayed. Even if the second time point T2 slightly later than the first time T1 In this case, the influence of the control delay is somewhat reduced by the target path correction processing according to the present embodiment.

[0045] Furthermore, no complicated computational processing is required for the target path correction processing according to the present embodiment. It is possible to determine the second target path. TP2 to obtain in a simple way by performing a simple coordinate transformation from the first coordinate system to the second coordinate system.

[0046] As a comparative example, the technology disclosed in the aforementioned patent literature 1 is considered. According to this technology, a "predictive processing" is necessary to calculate the second control command value with high precision. In particular, the vehicle motion state and the obstacle state, which are detected by the sensors, are used to predict a future vehicle motion state and obstacle state. The second control command value is then calculated with high precision based on the predicted future vehicle motion state and obstacle state. However, such predictive processing requires complex computational processing, which leads to an increase in computational load, computation time, and computational resources.

[0047] According to the present embodiment, forecast processing, as in the comparative example, is not necessary. For example, there is no need to consider the future second time point. T2 to predict the necessary information to be obtained in order to determine the second high-precision target path TP2 to calculate. These are the values ​​at the first point in time. T1 necessary information obtained, which is used to calculate the target path TP to be used. The first target path TP1 will be derived from the data at the first time T1 The necessary information obtained is calculated, and then the second target path is determined. TP2 This is obtained through a simple coordinate transformation. Since no complicated forecast processing is necessary, an increase in computational load, computation time, and computational resources is suppressed.

[0048] As described above, the autonomous driving system according to the present embodiment can increase path following performance while suppressing an increase in computational load. A specific configuration example of the autonomous driving system according to the present embodiment is described below. Configuration example of the autonomous driving system

[0049] Fig. 7 is a block diagram which shows a configuration example of the system. 100 for autonomous driving according to the present embodiment. The system 100 autonomous driving is on the vehicle 1 assembles and controls the autonomous driving of the vehicle. 1 The system 100 Autonomous driving requires, in particular, a GPS (Global Positioning System) receiver. 10 , a map database 20 , an environmental situation sensor 30, a vehicle condition sensor 40 , a communication device 50 , a driving device 60 and a control device 70 planned.

[0050] The GPS receiver 10 It receives signals transmitted by multiple GPS satellites and calculates the vehicle's position and orientation. 1 based on the received signals. The GPS receiver 10 sends the calculated information to the control device. 70 .

[0051] Information specifying the boundary position of each lane on a map is entered in advance into the map database. 20 The boundary position of each lane is represented by a group of points or a group of lines. The map database 20 is stored in a predetermined storage device.

[0052] The environmental situation sensor 30captures a situation around the vehicle 1 around. The environmental situation sensor 30 This is exemplified by a LIDAR (Laser Imaging Detection and Ranging) system, radar, a camera, and similar devices. The LIDAR uses laser light to locate a target around the vehicle. 1 to detect the area around the vehicle. The radar uses radio waves to locate a target around the vehicle. 1 to capture the surroundings. The camera creates a scene around the vehicle. 1 around. The environmental situation sensor 30 sends the captured information to the control device. 70 .

[0053] The vehicle condition sensor 40 detects a driving condition of the vehicle 1 The vehicle condition sensor 40This is exemplified by a vehicle speed sensor, a steering angle sensor, a yaw rate sensor, a lateral acceleration sensor, and the like. The vehicle speed sensor detects the vehicle's speed. 1 The steering angle sensor detects the steering angle of the vehicle. 1 The yaw rate sensor detects the yaw rate of the vehicle. 1 The lateral acceleration sensor detects the lateral acceleration of the vehicle. 1 The vehicle condition sensor 40 sends the captured information to the control device. 70 .

[0054] The communication device 50 It performs V2X communication (that is, vehicle-to-vehicle communication and vehicle-to-infrastructure communication). The communication device 50In particular, it performs V2V communication (vehicle-to-vehicle communication) with another vehicle. The communication device 50 It also performs V2I (vehicle-to-infrastructure) communication with surrounding infrastructure. The communication device can also use V2X communication. 50 Information about the environment around the vehicle 1 around obtaining the communication device 50 sends the obtained information to the control device. 70 .

[0055] The driving device 60It includes a steering device, a drive device, a braking device, a transmission, etc. The steering device steers the wheels. The drive device corresponds to a power source that generates a driving force. The drive device is exemplified by a machine or an engine and an electric motor. The braking device generates a braking force.

[0056] The control device 70 performs a control system for autonomous driving, which enables the autonomous driving of the vehicle. 1 controls. The control device 70 This typically corresponds to a microcomputer with a processor, a memory device, and an input / output interface. The control device 70 It is also referred to as an ECU (electronic control unit). The control device 70 It receives various pieces of information via the input / output interface. The control device 70It performs the control for autonomous driving based on the received information.

[0057] The control device 70 includes in particular an information acquisition unit 71 and a control unit 72 For autonomous driving, these functional blocks are used. These functional blocks are controlled by the processor of the control device. 70 , which executes a control program stored in the storage device. The control program can be stored on a computer-readable storage medium. The information acquisition unit 71 performs information retrieval processing. The control unit 72 For autonomous driving, the control processing for autonomous driving is carried out.

[0058] Fig. Figure 8 is a block diagram illustrating the information acquisition processing according to the present embodiment. During information acquisition processing, the information acquisition unit obtains 71 Information necessary for controlling autonomous driving. The information acquisition process is executed repeatedly in each specific cycle.

[0059] The information acquisition unit 71 obtains, in particular, position and orientation information. 81 from the GPS receiver 10 , which provides a current position and orientation of the vehicle 1 indicate.

[0060] Furthermore, the information acquisition unit reads 71 the information regarding traces from the map database 20 , to obtain track information 82 to generate the track information 82include a geometry (that is, position, shape, and orientation) of each track on a map. Based on the track information 82 can the information acquisition unit 71 It can detect lane merges, lane junctions, lane crossings, and the like. Furthermore, the information acquisition unit can 71 likewise, track curvature, track width, and the like, based on the track information. 82 calculate.

[0061] Furthermore, the information acquisition unit generates 71 based on the data from the environmental situation sensor 30 recorded information Environmental situation information 83 The environmental situation information 83 include target information regarding the target around the vehicle 1 around. The target is represented by an example of a white line, a road edge structure, a surrounding vehicle, and the like.

[0062] Furthermore, the information acquisition unit generates 71 based on the data from the vehicle condition sensor 40 Recorded information Vehicle condition information 84 The vehicle condition information 84 This includes information about the vehicle's speed, steering angle, yaw rate, lateral acceleration, etc. 1 .

[0063] Furthermore, the information acquisition unit 71 Feed and transfer information 85 via communication through the communication device 50 on. The supply information 85 This corresponds to information supplied by the infrastructure and the surrounding vehicle. The supplied information 85 Examples are provided by road construction section information, accident information, etc.

[0064] All information regarding position and orientation81 , the track information 82 , the environmental situation information 83 , the vehicle condition information 84 and the supply information 85 , as illustrated above, provide a color environment for the vehicle 1 Information that defines such a color environment of the vehicle 1 The information provided below is referred to as "Driving Environment Information 80". This means the driving environment information 80 The position and orientation information includes 81 , the track information 82 , the environmental situation information 83 , the vehicle condition information 84 and the supply information 85 .

[0065] It can be determined that the information acquisition unit 71 the control device 70 a function for obtaining driving environment information 80 owns. As in Fig. As shown in Figure 8, they form the information acquisition unit. 71 together with the GPS receiver 10 , the map database 20 , the environmental situation sensor 30 , the vehicle condition sensor 40 and the communication device 50 an "information acquisition device" 110" The information acquisition device 110 as part of the system 100 The information acquisition processing described above is carried out for autonomous driving.

[0066] Fig. Figure 9 is a block diagram illustrating the control processing for autonomous driving according to the present embodiment. The control unit 72 The control system for autonomous driving is based on the driving environment information described above. 80 through. The control unit 72Path following control, in particular, is a key component of autonomous driving control. In path following control, the control unit calculates... 72 for autonomous driving, the target path TP of the vehicle 1 and controls the vehicle's journey 1 , so that this corresponds to the target path TP follows. The vehicle's journey 1 can be achieved by appropriately operating the driving device 60 can be controlled.

[0067] The control unit 72 for autonomous driving and the driving device 60 form a "path sequence control device 120". The path sequence control device 120 as part of the system 100 Path following control is implemented for autonomous driving. The path following control is subsequently carried out by the path following control device. 120 as described in more detail according to the present embodiment. Path sequence control device

[0068] Fig. Figure 10 is a block diagram showing a functional configuration of the path-following control device. 120 as shown in the present embodiment. The path-following control device 120 comprises an acquisition unit 121 for necessary information, a target path determination unit 122 and a vehicle driving control unit 126 The target path determination unit 122 includes a target path calculation unit 123 and a target path correction unit 124 .

[0069] Fig. Figure 11 is a flowchart illustrating the path following control by the path following control device. 120 as shown in the present embodiment. The path following control by the path following control device. 120 According to the present embodiment, with reference to Fig. 10 and Fig. 11 described. Step S10:

[0070] The acquisition unit 121 necessary information obtained via the information acquisition device 110 periodically required information 90 The necessary information 90 correspond to the information required to calculate the target path. TP are necessary, and these correspond to part of the driving environment information described above. 80 The necessary information 90 This includes, for example, position and orientation information. 81 , the track information 82 , the environmental situation information 83 and the supply information 85 A point in time when the acquisition unit 121 For necessary information, the necessary information 90 attained corresponds to the first point in time T1 (see Fig. 3 and Fig. 6) The acquisition unit 121The necessary information is obtained to obtain the necessary information. 90 and provides the necessary information 90 at every first time T1 to the target path determination unit 122 out of. Step S20:

[0071] The target path determination unit 122 determines the target path TP based on the steps S10 necessary information obtained 90 The step S20 This includes in particular the following steps S30 to S50. Step S30:

[0072] First, the target path calculation unit performs 123 The goal path calculation processing is carried out. The goal path calculation unit 123 calculates the target path TP especially based on the step S10 necessary information obtained 90 Various methods for calculating the target path TP were proposed. In the present embodiment, the calculation method for the target path is TP not particularly limited. The necessary information 90 correspond to such information, which is found in the first position. P1 to be obtained, and which is based on the necessary information 90 calculated target path TP corresponds to the first target path defined in the first coordinate system TP1 (see Fig. 4) That is, the target path calculation unit 123 calculates the first target path TP1 based on the necessary information 90 . Step S40:

[0073] After the first target path TP1 Once calculated, the target path correction unit performs the calculation. 124 the target path correction processing by (see Fig. 5) The target path correction unit 124In particular, it performs a coordinate transformation from the first coordinate system to the second coordinate system in order to determine the first target path. TP1 on the second target path defined in the second coordinate system TP2 to correct (to convert).

[0074] The first coordinate system corresponds to the vehicle coordinate system at the first time point. T1 , if the necessary information 90 can be obtained. The second coordinate system corresponds to the vehicle coordinate system at the second time point. T2 , which is later than the first point in time T1 A difference between the first and second coordinate systems can, for example, arise from the position-orientation information. 81 both at the first time T1 as well as the second point in time T2can be calculated. Alternatively, a difference between the first coordinate system and the second coordinate system can be calculated based on the vehicle condition information. 84 (the vehicle speed, yaw rate, and the like) at the first time T1 and a delay from the first point in time T2 up to the second point in time T2 will be calculated.

[0075] It is preferable that the delay time be calculated from the first point in time. T1 up to the second point in time T2 is predetermined. In this case, setting information specifying the delay time is stored in advance in the memory of the control device. 70 saved. The target path correction unit 124 can the delay time and the second time T2 recognizing this based on the setting information. If the delay time is calculated from the initial time, T2up to the second point in time T2 Since the target path correction processing is predetermined, it is further simplified, which is preferable.

[0076] The delay time starting from the first point in time T1 up to the second point in time T2 is set, for example, to reduce the target path calculation time (that is, the time required for the target path calculation unit to complete). 123 the target path TP calculated). In this case, performing the target path correction processing makes it possible to reduce the impact of the control delay caused by the target path calculation time. Step S50:

[0077] The target path determination unit 122 represents the second target path obtained in step S40 TP2 as the target path TP one. Then the target path determination unit enters 122 the target path TP to the vehicle driving control unit 126 out of. Step S60:

[0078] The vehicle driving control unit 126 performs the vehicle driving control, which directs the vehicle's movement 1 controls, so that it follows the target path TP follows (see the Fig. 2 and Fig. 6) In particular, the vehicle's driving control unit calculates 126 based on parameters such as lateral deviation Ed , the difference in the angle of alignment θd , the curvature of the target path TP and similar vehicle control amounts to reduce the vehicle's deviation 1 from the target path TP Then the vehicle's driving control unit is activated. 126 the driving device 60 according to the calculated vehicle tax amount.

[0079] The driving device 60This includes, for example, a power steering system (EPS: electric power steering) for steering the vehicle's wheels. 1 It is possible to steer the wheels by controlling the drive motor of the power steering device. The vehicle's driving control unit 126 calculates a target steering angle that is used to follow the target path TP is required. Additionally, the vehicle's driving control unit gains 126 an actual steering angle from the vehicle status information 84 Then the vehicle's driving control unit calculates 126 A motor current command value is generated based on the difference between the actual steering angle and the target steering angle, and the motor is driven according to this command value. This is how vehicle driving control is achieved. Modification example

[0080] The delay time from the first point in time T1 until the second point in timeT2 is not necessarily limited to the target path calculation time. The delay time starting from the first time point T1 up to the second point in time T2 It can be set, for example, taking into account the information communication time, the actuator response time, and the like.

[0081] If the delay time starts from the first point in time T1 up to the second point in time T2 Since the target path calculation time corresponds to the delay time, the delay time can be measured as the actual delay time instead of specifying a predetermined value. In particular, the target path calculation unit measures 123 in the step described above S30 a processing time of the target path calculation processing and gives the measurement result to the target path correction unit 124 off. The target path correction unit 124 can the second time T2and identify the second coordinate system based on the measurement result. Second embodiment (short version)

[0082] The necessary information 90 , which are used to calculate the target path TP The necessary information is obtained and updated periodically. At any time when the necessary information is available... 90 The target path will also be updated. TP determined and updated. In the following description, a suffix "k-1" represents the preceding and a suffix "k" represents the last.

[0083] Fig. 12 and Fig. Figure 13 shows an example of updating the necessary information. 90 and the target path TP At the preceding first time point Tl(k-1), the previously necessary information is obtained. 90attained. At the preceding second time point T2(k-1), the previous target path TP(k-1) is obtained. At the first time point T1(k), the new necessary information is obtained. 90 attained. At the second time point T2(k), the new target path TP(k) is obtained. That is, the target path TP will be updated.

[0084] During a period from the first time T1(k) to the second time T2(k), the new target path TP(k) is calculated, but this path is not yet determined. Therefore, during this period, vehicle control is performed based on the previous target path TP(k-1). At the second time T2(k), the new target path TP(k) is determined. Afterward, vehicle control can be performed based on the new target path TP(k).

[0085] Here, a case is considered in which the previous target path TP(k-1) and the new target path TP(k) differ from each other and are not continuous, as in Fig. Figure 13 shows that in this case, the vehicle control amount changes during vehicle driving control at a time when the target path TP The switching occurs discontinuously. The discontinuous change in the vehicle control amount causes a sudden change and a disturbance in the vehicle's behavior, conveying to the vehicle's occupant a sense of unease. 1 Hence, a strange and anxious feeling. In light of the foregoing, the second embodiment of the present disclosure proposes a target path calculation processing that can suppress the discontinuous change in the vehicle control amount.

[0086] Fig. Figure 14 is a conceptual illustration to explain the target path calculation processing in the second embodiment. According to the second embodiment, the new target path TP(k) is determined to partially overlap the previous target path TP(k-1). In particular, as shown in Fig. As shown in Figure 14, the new target path TP(k) is determined such that a specific segment starting from the beginning of the new target path TP(k) overlaps the previous target path TP(k-1). The specific segment includes at least a segment starting from the first position P1(k) at the first time T1(k) to the second position P2(k) at the second time T2(k).

[0087] Due to the target path calculation processing described above, the new target path TP(k) and the previous target path TP(k-1) are seamlessly connected. Specifically, the new target path TP(k) overlaps the previous target path TP(k-1) in the section from the first position P1(k) to the second position P2(k). Therefore, there is no discontinuity between the previous target path TP(k-1) and the new target path TP(k) at the second position P2(k). Consequently, the discontinuous change in the vehicle control amount is suppressed when the target path TP The system is switched or changed. Consequently, sudden changes and disturbances in vehicle behavior are suppressed. Path sequence control device

[0088] Fig. Figure 15 is a block diagram showing a functional configuration of the path sequencing control device. 120 as shown in the second embodiment. An overlapping description with the one in Fig. The first embodiment shown in 10 is appropriately omitted. The path-following control device 120 According to the second embodiment, a target path determination unit comprises 122A instead of the target path determination unit 122 The target path determination unit 122A includes a target path calculation unit 123A .

[0089] Fig. Figure 16 is a flowchart illustrating the path following control by the path following control device. 120 as shown in the second embodiment. An overlapping description with the one in Fig. In the first embodiment shown in 11, step 11 is appropriately omitted. In the second embodiment, step 11 is omitted. S20 replaced by step S20A. Step S20A:

[0090] The target path determination unit 122A determines the target path TP based on the steps S10 necessary information obtained 90The step S20A includes in particular the following step S30A . Step S30A:

[0091] The target path calculation unit 123A Performs the target path calculation processing based on the necessary information 90 and the previous target path TP(k-1). The target path calculation unit 123A In particular, it calculates the new target path TP(k) such that a certain segment starting from the beginning of the new target path TP(k) overlaps the previous target path TP(k-1). The certain segment includes at least the segment from the first position P1(k) to the second position P2(k).

[0092] The target path determination unit 122A gives the at step S30A calculated target path TP(k) to the vehicle driving control unit 126 out. The target path TP The system switches from the previous target path TP(k-1) to the new target path TP(k) and the vehicle driving control unit 126 The vehicle control system starts based on the new target path TP(k). At the switching point, discontinuous changes in the vehicle control amount are suppressed. Consequently, sudden changes and disturbances in vehicle behavior are suppressed. Third embodiment

[0093] A third embodiment of the present disclosure corresponds to a combination of the first and second embodiments. An overlapping description with either the first or second embodiment is appropriately omitted.

[0094] Fig. Figure 17 is a block diagram showing a functional configuration of the path-following control device. 120as shown in the third embodiment. The path following control device 120 according to the third embodiment comprises a target path determination unit. 122B instead of the target path determination unit 122 The target path determination unit 122B includes a target path calculation unit 123B and a target path correction unit 124B .

[0095] Fig. 18 is a flowchart showing the path following control by the path following control device. 120 as shown in the third embodiment. In the third embodiment, the step S20 replaced by a step S20B. Step S20B:

[0096] The target path determination unit 122B determines the target path TP based on the steps S10 necessary information obtained 90 The step S20B This includes in particular the following steps S30B to S50B. Step S30B:

[0097] The target path calculation unit 123B Performs the target path calculation processing based on the necessary information 90 and the previous target path TP(k-1). The target path calculation unit 123B The new target path TP(k) is calculated, in particular, such that a specific segment starting from the beginning of the new target path TP(k) overlaps the previous target path TP(k-1). This specific segment includes at least the section from the first position P1(k) to the second position P2(k). The target path TP(k) calculated in step S30B corresponds to the first target path TP1(k) defined in the first coordinate system. Step S40B:

[0098] After the last first target path TP1(k) has been calculated, the target path correction unit performs 124B the target path correction processing by (see Fig. 5) The target path correction unit 124BIn particular, it performs a coordinate transformation from the first coordinate system to the second coordinate system in order to correct the first target path TP1(k) to the second target path TP2(k) defined in the second coordinate system. Step S50B:

[0099] The target path determination unit 122B represents the step S40B obtained second target path TP2(k) as the target path TP one. Then the target path determination unit enters 122B the target path TP to the vehicle driving control unit 126 out of.

[0100] According to the third embodiment, both the effects of the first embodiment and the effects of the second embodiment are obtained. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2010

[0003] JP 173616 A

[0003] JP 2016

[0003] JP 099713 A

[0003]

Claims

[1] System (100) for autonomous driving, which is mounted on a vehicle (1), comprising: a acquisition unit (121) for necessary information, which periodically acquires necessary information (90) that is required to calculate a target path (TP); a target path determination unit (122) which determines the target path (TP) based on the necessary information (90); and a vehicle driving control unit (126) which performs vehicle driving control that controls a journey of the vehicle (1) to follow the destination path (TP), wherein a vehicle coordinate system corresponds to a relative coordinate system defined for the vehicle (1), a first time point (T1) corresponds to a time point at which the acquisition unit (121) obtains the necessary information (90) for necessary information, a first coordinate system corresponds to the vehicle coordinate system at the first time point (T1), a second coordinate system corresponds to the vehicle coordinate system at a second time point (T2), which is later than the first time point (T1), the target path determination unit (122) exhibits: a target path calculation unit (123) which calculates a first target path (TP1) defined in the first coordinate system based on the necessary information (90) obtained at the first time (T1); and a target path correction unit (124) which corrects the first target path (TP1) to a second target path (TP2) defined in the second coordinate system by performing a coordinate transformation from the first coordinate system to the second coordinate system, and The vehicle driving control unit (126) uses the second destination path (TP2) as the destination path (TP) to perform vehicle driving control. [2] System (100) for autonomous driving according to claim 1, wherein a delay time is predetermined from the first time (T1) to the second time (T2). [3] System (100) for autonomous driving according to claim 1 or 2, wherein a delay time from the first time (T1) to the second time (T2) corresponds to a time required for the destination path calculation unit (123) to calculate the first destination path (TP1). [4] System (100) for autonomous driving according to claim 3, wherein The target path determination unit (122B) determines and updates the target path (TP) at every time the acquisition unit (121) obtains the necessary information (90), the target path determination unit (122B) determines a new target path (TP(k)) such that a certain segment starting from the beginning of the new target path (TP(k)) overlaps a previous target path (TP(k-1)), and the specific section includes at least one section corresponding to a time period starting from the first time point (T1) to the second time point (T2).

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