Operation control method and operation control device

Abstract

A processor 10 of a driving control device 100 according to the present invention: determines whether or not an intersection T is present to the downstream side of a host vehicle 1, and, if the intersection T is present, sets a deceleration rate switching position Pk which obtains the prescribed switching determination distance Xa to the upstream side from a prescribed object in the intersection T, acquires a stop position Ps to the upstream side of the intersection T and to the downstream side of the deceleration rate switching position Pk, and generates a vehicle speed profile such that the host vehicle 1 decelerates at a primary deceleration rate Acoast between a deceleration start position P0 and the deceleration rate switching position Pk and decelerates at a secondary deceleration rate Ath, which is higher than the primary deceleration rate Acoast, between the deceleration rate switching position Pk and the stop position Ps, and, if the state of the object satisfies a stop condition, the host vehicle 1 stops at the stop position Ps.

Description

[Technical Field]

[0001] The present invention relates to an operation control method and an operation control device. [Background technology]

[0002] In the driving control method described in Patent Document 1, when it is detected that there is a traffic light downstream of the vehicle, the vehicle first decelerates at a predetermined deceleration rate, and then, when the vehicle reaches the limit position where it can stop, if the color of the traffic light cannot be identified or the traffic light is displaying a stop signal, the deceleration rate is increased and the vehicle stops in front of the traffic light (see Figure 3 of Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-173723 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the driving control method described in Patent Document 1, the "limit position at which the vehicle can stop," which is the position at which the deceleration is switched, is set according to the stopping position at which the vehicle stops.Therefore, the further upstream the stopping position is from the target traffic light, the earlier the timing at which the deceleration is switched, which could disrupt the flow of traffic behind.

[0005] The problem that the present invention aims to solve is to provide a driving control method and a driving control device that can switch deceleration while reducing the possibility of disrupting the following traffic flow when the vehicle stops at a stopping position upstream of an intersection. [Means for solving the problem]

[0006] The present invention solves the above problem by generating a vehicle speed profile so that the vehicle decelerates at a primary deceleration rate from a predetermined deceleration start position located upstream of the distance at which the vehicle's detection device can recognize a predetermined object at an intersection, decelerates at a secondary deceleration rate higher than the primary deceleration rate from a deceleration switch position located at the upper limit of the distance at which the vehicle's detection device can recognize the object, and stops at a stop position. [Effects of the Invention]

[0007] According to the present invention, the deceleration switching position is set in advance, which has the effect of enabling the deceleration to be switched while reducing the possibility of disrupting the following traffic flow when the vehicle stops at a stopping position upstream of the intersection. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing the configuration of an operation control device according to an embodiment of the present invention; [Figure 2] 2 is a diagram showing the positional relationship between a vehicle whose driving is controlled by the driving control device shown in FIG. 1 and a traffic light which is an object at an intersection. FIG. [Figure 3] 2 is a graph showing an example of a primary deceleration profile and a secondary deceleration profile generated by the operation control device shown in FIG. 1. [Figure 4] 10 is a graph showing another example of a primary deceleration profile and a secondary deceleration profile generated by the operation control device shown in FIG. [Figure 5] 2 is an example of a graph showing a virtual deceleration profile and a secondary deceleration profile generated by the operation control device shown in FIG. 1. [Figure 6] 2 is a flowchart showing the procedure of an operation control method executed by the operation control device shown in FIG. [Figure 7] 2 is a diagram showing the positional relationship between a vehicle whose driving is controlled by the driving control device shown in FIG. 1 and a crosswalk which is an object at the intersection. FIG. [Figure 8]1. FIG. 4 is a diagram showing another example of the positional relationship between a vehicle whose driving is controlled by the driving control device shown in FIG. 1 and a traffic light which is an object at an intersection. [Figure 9] 9 is a graph showing examples of a plurality of primary deceleration profiles and secondary deceleration profiles generated by the operation control device shown in FIG. 1 in the example shown in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a block diagram showing the configuration of a host vehicle 1 and a driving control device 100 that controls autonomous driving of the host vehicle 1. The host vehicle 1 includes the driving control device 100, a detection device 101, a host vehicle position acquisition unit 102, a map database 103, and a drive control device 104.

[0010] The detection device 101 has either an on-board camera that captures images of the surroundings of the vehicle or a radar (LIDAR) that detects moving objects and obstacles around the vehicle, or both. The detection results of the detection device 101 are output to the driving control device 100 at predetermined time intervals. The objects detected by the detection device 101 are, for example, traffic lights or crosswalks. If the object is a traffic light, the detection device 101 detects the signal (color) emitted by the traffic light. If the object is a crosswalk, the detection device 101 detects the presence or absence of moving objects such as pedestrians, bicycles (two-wheeled vehicles), wheelchairs, etc. on the crosswalk.

[0011] The vehicle position acquisition unit 102 is composed of a GPS unit, a gyro sensor, a vehicle speed sensor, etc. The vehicle position acquisition unit 102 detects radio waves transmitted from multiple satellite communications using the GPS unit, periodically acquires position information of the vehicle 1, and detects the current position of the vehicle 1 based on the acquired position information of the vehicle 1, angle change information acquired from the gyro sensor, and vehicle speed acquired from the vehicle speed sensor. The position information of the vehicle 1 detected by the vehicle position acquisition unit 102 is output to the driving control device 100 at predetermined time intervals.

[0012] The map database 103 is a memory configured to store three-dimensional high-precision map information including position information of various facilities and specific points, and to be accessible from the driving control device 100. The map database 103 stores high-precision digital map information (high-precision maps, dynamic maps). The high-precision map information includes the positions of intersections. The high-precision map information also includes the positions of stop lines where the vehicle 1 should stop according to predetermined conditions.

[0013] The drive control device 104 controls the driving of the vehicle 1 based on the control commands of the driving control device 100. For example, the drive control device 104 uses an autonomous speed control function to control the operation of the drive mechanism for adjusting acceleration / deceleration and vehicle speed (including the operation of the internal combustion engine in an engine vehicle, the operation of the traction motor in an electric vehicle, and the torque distribution between the internal combustion engine and the traction motor in a hybrid vehicle) and the braking operation.

[0014] Next, the configuration of the operation control device 100 will be described in detail with reference to FIGS. As shown in FIG. 1, the driving control device 100 includes a processor 10. The processor 10 includes a read-only memory (ROM) that stores a program for controlling the driving of the vehicle, a central processing unit (CPU) that executes the program stored in the ROM, and a random access memory (RAM) that functions as an accessible storage device. Note that, instead of or in addition to the central processing unit (CPU), an MPU (microprocessing unit), a digital signal processor (DSP), an application specific integrated circuit (ASIC), or a field programmable gate array (FPGA) may be used as an operating circuit. The processor 10 includes an intersection passage determination unit 11, a vehicle speed limit acquisition unit 12, a vehicle speed profile generation unit 13, a secondary deceleration determination unit 14, a vehicle speed profile switching unit 15, and a vehicle speed control unit 16. The intersection passage determination unit 11, the vehicle speed limit acquisition unit 12, the vehicle speed profile generation unit 13, the secondary deceleration determination unit 14, the vehicle speed profile switching unit 15, and the vehicle speed control unit 16 execute programs for implementing the respective functions of the processor 10. In FIG. 1, the driving control device 100 is mounted on the vehicle 1, but the invention is not limited to this, and the driving control device 100 may be a device that remotely controls the vehicle 1.

[0015] The intersection passage determination unit 11 includes an intersection determination unit 114, a deceleration switching position setting unit 111, a stop position acquisition unit 112, and a switching distance acquisition unit 113. The intersection determination unit 114 determines whether an intersection exists downstream (forward) of the host vehicle 1 based on information from the map database 103, the position information of the host vehicle 1 acquired by the host vehicle position acquisition unit, and the detection results of the detection device 101. Furthermore, as shown in FIG. 2, the deceleration switching position setting unit 111 sets a deceleration switching position Pk that is a predetermined switching determination distance Xa upstream from a traffic light B1, which is a predetermined object at the intersection T. Note that the switching determination distance Xa is a distance at which the detection device 101 of the host vehicle 1 can recognize the traffic light B1, which is the object. The stop position acquisition unit 112 acquires a stop position Ps, which is a position where the host vehicle 1 should stop when the state of the object (traffic light B1) satisfies a predetermined stop condition. The stop position Ps is located upstream of the intersection T and downstream of the deceleration switching position Pk. The stop position Ps is the position of a stop line S marked on the road surface, but is not limited thereto and may be the position of a virtual stop line set by the stop position acquisition unit 112. The stop line S does not include a temporary stop line, which is a stop line where the host vehicle 1 should stop regardless of whether a stop condition is satisfied. If the object is a traffic light B1, "when the state of the object satisfies a predetermined stop condition" refers to, for example, when the traffic light B1 is displaying a stop signal (when the traffic light B1's signal color is red) or when the detection device 101 cannot detect the signal color of the traffic light B1. The stop signal displayed by the traffic light B1 may also include when the traffic light B1's signal color is yellow. The detection device 101 may not be able to detect the signal color of the traffic light B1 due to, for example, weather such as a snowstorm, a malfunction of the traffic light B1, a road shape such as a curve, or a large vehicle such as a truck. The switching distance acquisition unit 113 acquires a switching distance Xth between the deceleration switching position Pk and the stop position Ps.

[0016] The vehicle speed limit acquisition unit 12 acquires the vehicle speed limit from image information of the speed limit sign detected by the detection device 101 or from vehicle speed limit information included in navigation data or map data. The vehicle speed limit is set as the initial vehicle speed Vnow at the deceleration start position P0.

[0017] The vehicle speed profile generator 13 generates a vehicle speed profile so that the host vehicle 1 stops at a stop position Ps when the state of the object satisfies a predetermined stop condition. The vehicle speed profile generator 13 has a primary deceleration profile generator 131, a secondary deceleration profile generator 132, and a virtual deceleration profile generator 133. The primary deceleration profile generated by the primary deceleration profile generator 131 and the secondary deceleration profile generated by the secondary deceleration profile generator 132 each have an initial vehicle speed Vnow of the host vehicle 1 at a deceleration start position P0, an initial distance Xnow between the deceleration start position P0 and the stop position Ps, a switch vehicle speed Vth of the host vehicle 1 at a deceleration switch position Pk, and a switch distance Xth between the deceleration switch position Pk and the stop position Ps.

[0018] 3, the primary deceleration profile generator 131 generates a primary deceleration profile G1 so that the host vehicle 1 decelerates between the deceleration start position P0 and the deceleration switching position Pk at a predetermined primary deceleration Acoast. The primary deceleration Acoast is a deceleration (e.g., 0.04 G) that does not cause the brake lights of the host vehicle 1 to light up. The primary deceleration Acoast is calculated by the following equation (1) based on the initial vehicle speed Vnow at the deceleration start position P0 and the initial distance Xnow between the deceleration start position P0 and the stop position Ps so that the vehicle speed of the host vehicle 1 becomes a predetermined switching vehicle speed Vth at the deceleration switching position Pk.

number

[0019] 2, a virtual position Poffset is set in the primary deceleration profile generated by the primary deceleration profile generating unit 131, where the vehicle speed of the host vehicle 1 becomes 0. The vehicle speed V of the host vehicle 1 in the primary deceleration profile is calculated by the following equation (2) based on the primary deceleration Acoast and the virtual distance Xoffset between the stop position Ps and the virtual position Poffset. Note that in the example of FIG. 2, the virtual position Poffset is located downstream of the stop position Ps, so the virtual distance Xoffset takes a negative value.

number

[0020] On the other hand, the secondary deceleration profile generation unit 132 generates a secondary deceleration profile G2 so that the host vehicle 1 decelerates at a predetermined secondary deceleration Ath between the deceleration switching position Pk and the stop position Ps, as shown in the graph of Fig. 3. In the secondary deceleration profile, the vehicle speed V of the host vehicle 1 is calculated based on the switching vehicle speed Vth using the following equation (3) so that the host vehicle 1 stops at the stop position Ps. Note that the secondary deceleration profile generation unit 132 sets the secondary deceleration Ath to be higher than the primary deceleration Acoast. The secondary deceleration Ath is a deceleration (e.g., 0.25G) that does not impair the ride comfort of the occupants of the host vehicle 1.

number

[0021] 3, the vehicle speed profile generation unit 13 generates a vehicle speed profile such that the host vehicle 1 travels at an initial vehicle speed Vnow (vehicle speed limit) to a deceleration start position P0 and decelerates at a primary deceleration rate Acoast between the deceleration start position P0 and a stop position Ps. The vehicle speed profile generation unit 13 also generates a vehicle speed profile such that the host vehicle 1 decelerates between the deceleration switching position Pk and the stop position Ps at a secondary deceleration rate Ath that is higher than the primary deceleration rate Acoast, and stops at the stop position Ps when the object satisfies the stop condition. That is, the vehicle speed profile generation unit 13 generates a vehicle speed profile such that, when the state of the object satisfies the stop condition at the timing when the host vehicle 1 passes the deceleration switching position Pk, the host vehicle 1, which has been decelerating at the primary deceleration rate Acoast between the deceleration start position P0 and the deceleration switching position Pk, decelerates at the secondary deceleration rate Ath after passing the deceleration switching position Pk and stops at the stop position Ps.

[0022] As shown in FIGS. 3 and 4, the secondary deceleration profile generator 132 sets the secondary deceleration Ath based on the switching distance Xth between the deceleration switching position Pk and the stop position Ps. That is, the secondary deceleration Ath is set so that the secondary deceleration Ath2 corresponding to the second switching distance Xth2 shown in FIG. 4, which is shorter than the first switching distance Xth1, is higher than the secondary deceleration Ath1 corresponding to the first switching distance Xth1 shown in FIG. 3. That is, the secondary deceleration profile generator 132 sets the secondary deceleration Ath so that it is higher as the switching distance Xth is shorter. The secondary deceleration profile generator 132 sets the secondary deceleration Ath using a predetermined secondary deceleration upper limit value Alim as an upper limit. When the secondary deceleration profile generator 132 sets the secondary deceleration Ath to the secondary deceleration upper limit value Alim, the vehicle speed profile generator 13 adjusts the switching vehicle speed Vth in accordance with the secondary deceleration upper limit value Alim. Furthermore, the primary deceleration profile generator 131 generates a primary deceleration profile in accordance with the secondary deceleration upper limit value Alim and the switching vehicle speed Vth. The secondary deceleration upper limit value Alim is an upper limit value of deceleration that does not impair the riding comfort of the occupants of the host vehicle 1 and does not excessively affect other following vehicles (to the extent that the deceleration of the host vehicle 1 does not become sudden).

[0023] 3 and 4, the vehicle speed profile generation unit 13 sets the switch vehicle speed Vth based on the switch distance Xth between the deceleration switch position Pk and the stop position Ps. That is, the switch vehicle speed Vth is set so that the switch vehicle speed Vth2 corresponding to the second switch distance Xth2 shown in FIG. 4, which is shorter than the first switch distance Xth1, is lower than the switch vehicle speed Vth1 corresponding to the first switch distance Xth1 shown in FIG. 3. That is, the vehicle speed profile generation unit 13 sets the switch distance Xth so that the shorter the switch distance Xth is, the lower the switch distance Xth is. Note that the vehicle speed profile generation unit 13 sets the switch vehicle speed Vth using a predetermined vehicle speed upper limit value Vlim as an upper limit. When the vehicle speed profile generation unit 13 sets the vehicle speed upper limit value Vlim as the switch vehicle speed Vth, the primary deceleration profile generation unit 131 and the secondary deceleration profile generation unit 132 generate the primary deceleration profile and the secondary deceleration profile according to the vehicle speed upper limit value Vlim. The upper vehicle speed limit Vlim is set to a value lower than the vehicle speed limit (initial vehicle speed Vnow).

[0024] 3 and 4, the vehicle speed profile generating unit 13 sets the deceleration start position P0 based on the switching determination distance Xa. In the example of FIG. 3, the switching determination distance Xa is a first switching determination distance Xa1, and in the example of FIG. 4, the switching determination distance Xa is a second switching determination distance Xa2 that is shorter than the first switching determination distance Xa1. In the examples of FIG. 3 and FIG. 4, the stop position Ps is assumed to be the same. The deceleration start position P0 is set so that the deceleration start position P02 corresponding to the second switching determination distance Xa2 shown in FIG. 4 is located further downstream than the deceleration start position P01 corresponding to the first switching determination distance Xa1 shown in FIG. 3. In other words, the shorter the switching determination distance Xa, the more downstream the deceleration start position P0 is set.

[0025] 5, the virtual deceleration profile generation unit 133 of the vehicle speed profile generation unit 13 shown in FIG. 1 calculates a virtual deceleration Ax when it is assumed that the host vehicle 1 decelerates at a constant virtual deceleration Ax between the deceleration start position P0 and the stop position Ps and stops at the stop position Ps. The vehicle speed profile generation unit 13 generates a virtual deceleration profile G3 based on the virtual deceleration Ax. If the virtual deceleration Ax is higher than the secondary deceleration upper limit value Alim, the vehicle speed profile generation unit 13 regenerates the vehicle speed profile so that the host vehicle 1 decelerates at the virtual deceleration Ax between the deceleration start position P0 and the stop position Ps, as shown by the arrow in FIG. 5. That is, if the timing at which the intersection passage determination unit 11 determines that the host vehicle 1 has passed through the intersection T is later than a predetermined timing based on the deceleration switching timing at which the host vehicle 1 passes through the deceleration switching position Pk, the virtual deceleration Ax becomes higher than the secondary deceleration upper limit value Alim. In this case, the vehicle speed profile generation unit 13 selects the virtual deceleration profile G3 as the vehicle speed profile.

[0026] 1 determines whether or not to switch the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath at the deceleration switching position Pk based on the detection result of the detection device 101. Specifically, the secondary deceleration determination unit 14 determines whether or not the state of the object satisfies a stop condition when the host vehicle 1 passes through the deceleration switching position Pk, and determines to switch the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath when the state of the object satisfies the stop condition (for example, when traffic light B1 is displaying a stop signal or when the detection device 101 cannot detect the signal color of traffic light B1).

[0027] Furthermore, when the secondary deceleration determination unit 14 determines that the deceleration of the host vehicle 1 should be switched from the primary deceleration rate Acoast to the secondary deceleration rate Ath, the vehicle speed profile switching unit 15 switches the vehicle speed profile after the host vehicle 1 passes through the deceleration switching position Pk from the primary deceleration profile G1 to the secondary deceleration profile G2. On the other hand, when the secondary deceleration determination unit 14 determines that the deceleration of the host vehicle 1 should not be switched from the primary deceleration rate Acoast to the secondary deceleration rate Ath, the vehicle speed profile switching unit 15 cancels the execution of driving control in accordance with the vehicle speed profile after the host vehicle 1 passes through the deceleration switching position Pk, without switching the vehicle speed profile from the primary deceleration profile G1 to the secondary deceleration profile G2. In other words, when the state of the object does not satisfy the stop condition, the vehicle speed V of the host vehicle 1 returns to the initial vehicle speed Vnow, and the host vehicle 1 passes through the intersection T at the initial vehicle speed Vnow. Furthermore, if the secondary deceleration determination unit 14 determines not to switch the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath, the host vehicle 1 may pass through the intersection T while maintaining the vehicle speed V at the switching vehicle speed Vth. Furthermore, as shown in Fig. 5, if the virtual deceleration Ax is higher than the secondary deceleration upper limit value Alim and the degree of satisfaction of the stop condition is greater than a predetermined value, the vehicle speed profile switching unit 15 switches the vehicle speed profile so that the host vehicle 1 decelerates at the virtual deceleration Ax or the maximum deceleration Amax.

[0028] 5, when the virtual deceleration is higher than a predetermined maximum deceleration Amax and the degree of fulfillment of the stop condition is equal to or lower than a predetermined value (for example, when the traffic light B1 is yellow or green), the vehicle speed profile switching unit 15 cancels the execution of the driving control according to the vehicle speed profile (virtual deceleration profile G3) set by the vehicle speed profile generation unit 13. That is, when the virtual deceleration is higher than the predetermined maximum deceleration Amax and the degree of fulfillment of the stop condition is equal to or lower than a predetermined value, the host vehicle 1 passes through the stop position Ps at the initial vehicle speed Vnow without decelerating. On the other hand, even when the virtual deceleration Ax is higher than the predetermined maximum deceleration Amax, the vehicle speed profile switching unit 15 does not cancel the execution of the driving control according to the vehicle speed profile when the degree of fulfillment of the stop condition is higher than a predetermined value (for example, when the traffic light B1 is red or when a moving object such as a pedestrian is passing through the crosswalk at the intersection T). That is, if the virtual deceleration Ax is higher than a predetermined maximum deceleration Amax and the degree of fulfillment of the stop condition is greater than a predetermined value, the host vehicle 1 decelerates at the maximum deceleration Amax and stops downstream of the stop position Ps. Note that the maximum deceleration Amax is the upper limit of the deceleration that the host vehicle 1 can achieve.

[0029] The vehicle speed control unit 16 outputs a command to the drive control device 104 to control the vehicle speed of the host vehicle 1 based on the vehicle speed profile generated by the vehicle speed profile generation unit 13 and the result of switching the vehicle speed profile by the vehicle speed profile switching unit 15. Note that the vehicle speed control unit 16 determines whether the state of the object can be determined when the host vehicle 1 is traveling upstream of the deceleration start position P0, and if the state of the object cannot be determined, starts executing driving control in accordance with the vehicle speed profile at the deceleration start position P0. Specifically, if the detection device 101 cannot detect the signal color of the traffic light B1 when the host vehicle 1 is traveling upstream of the deceleration start position P0, the host vehicle 1 starts deceleration at the deceleration start position P0 in accordance with the vehicle speed profile generated by the vehicle speed profile generation unit 13.

[0030] Next, the procedure of the operation control method executed by the operation control device 100 will be described with reference to FIG. 6, the intersection determination unit 114 of the intersection passage determination unit 11 determines whether or not an intersection T exists downstream (ahead) of the host vehicle 1. If the intersection determination unit 114 determines that an intersection T does not exist downstream of the host vehicle 1, the processor 10 ends the processing.

[0031] On the other hand, if the processor 10 determines that an intersection T is located downstream of the vehicle 1, the deceleration switching position setting unit 111 sets the deceleration switching position Pk in step S2. Then, the stop position acquisition unit 112 acquires the stop position Ps in step S3.

[0032] Next, in step S4, the primary deceleration profile generator 131 and the secondary deceleration profile generator 132 generate a primary deceleration profile G1 and a secondary deceleration profile G2, respectively, based on the switching determination distance Xa, the initial distance Xnow, and the initial vehicle speed Vnow.

[0033] Next, in step S5, vehicle speed profile generation unit 13 determines whether or not secondary deceleration Ath generated by secondary deceleration profile generation unit 132 is equal to or less than secondary deceleration upper limit value Alim. If secondary deceleration Ath is higher than secondary deceleration upper limit value Alim, vehicle speed profile generation unit 13 resets secondary deceleration Ath to secondary deceleration upper limit value Alim in step S6, and again generates the primary deceleration profile and the secondary deceleration profile in step S4.

[0034] On the other hand, if it is determined in step S5 that the secondary deceleration Ath is equal to or less than the secondary deceleration upper limit Alim, the vehicle speed profile generator 13 determines in step S7 whether the switch vehicle speed Vth at the deceleration switch position Pk is equal to or less than the vehicle speed upper limit Vlim. If the switch vehicle speed Vth is higher than the vehicle speed upper limit Vlim, the vehicle speed profile generator 13 resets the switch vehicle speed Vth to the vehicle speed upper limit Vlim in step S8, and regenerates the primary deceleration profile and the secondary deceleration profile again in step S4.

[0035] Next, in step S7, if it is determined that the switching vehicle speed Vth is equal to or less than the vehicle speed upper limit value Vlim, the vehicle speed profile generation unit 13 determines in step S9 whether the virtual deceleration Ax generated by the virtual deceleration profile generation unit 133 is equal to or less than the secondary deceleration upper limit value Alim.

[0036] If it is determined in step S9 that the virtual deceleration Ax is higher than the secondary deceleration upper limit value Alim, then in step S10 the vehicle speed profile generator 13 determines whether the virtual deceleration Ax is equal to or less than the maximum deceleration Amax. If the virtual deceleration Ax is equal to or less than the maximum deceleration Amax, then in step S11 the vehicle speed profile generator 13 regenerates the vehicle speed profile so that the host vehicle 1 decelerates at the virtual deceleration Ax between the deceleration start position P0 and the stop position Ps.

[0037] On the other hand, if it is determined in step S10 that the virtual deceleration Ax generated by the virtual deceleration profile generation unit 133 is higher than the maximum deceleration Amax, then in step S12, the processor 10 determines whether the degree to which the state of the object satisfies the stop condition is equal to or less than a predetermined value. Specifically, if the object is traffic light B1, then in step S12, the processor 10 determines that the degree to which the state of the object satisfies the stop condition is equal to or less than a predetermined value when the signal color of traffic light B1 is yellow or green. If it is determined in step S12 that the degree to which the stop condition is satisfied is higher than the predetermined value, then in step S13, the vehicle speed profile generation unit 13 regenerates the vehicle speed profile so that the host vehicle 1 decelerates at the maximum deceleration Amax between the deceleration start position P0 and the stop position Ps. On the other hand, if it is determined in step S12 that the state of the object satisfies the stopping condition to a degree equal to or less than a predetermined value, the vehicle speed profile switching unit 15 releases the driving control according to the vehicle speed profile in step S14 so that the host vehicle 1 passes through the stopping position Ps at the initial vehicle speed Vnow without decelerating.

[0038] Next, if it is determined in step S9 that the virtual deceleration Ax is higher than the secondary deceleration upper limit value Alim, the vehicle speed profile generation unit 13 determines in step S15 whether the state of the object satisfies the stop condition. "When the state of the object satisfies the stop condition" means, for example, when the traffic light B1 is displaying a stop signal, or when the detection device 101 of the host vehicle 1 cannot detect the signal displayed by the traffic light B1. On the other hand, "When the state of the object does not satisfy the stop condition" means, for example, when the detection device 101 of the host vehicle 1 detects that the signal color of the traffic light B1 is green.

[0039] If it is determined in step S15 that the state of the object satisfies the stopping condition, the vehicle speed profile switching unit 15 switches the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath at the deceleration switching position Pk. On the other hand, if it is determined in step S15 that the state of the object does not satisfy the stopping condition, the vehicle speed profile switching unit 15 cancels the execution of the driving control according to the vehicle speed profile in step S17 so that the host vehicle 1 passes through the intersection T at the initial vehicle speed Vnow.

[0040] 6, the driving control device 100 may omit the processing of steps S5 and S6, the processing of steps S7 and S6, and the processing of steps S9 to S14. Alternatively, the driving control device 100 may omit all of the processing of steps S5 to S14, and after the vehicle speed profile generator 13 generates the primary deceleration profile G1 in step S4, determine in step S15 whether the state of the object satisfies the stop condition.

[0041] As described above, the processor 10 of the driving control device 100 according to this embodiment sets a deceleration switching position Pk at a predetermined switching determination distance Xa upstream from a predetermined object (traffic light B1) at the intersection T. The processor 10 acquires a stop position Ps upstream of the intersection T and downstream of the deceleration switching position. The vehicle speed profile generator 13 of the processor 10 then generates a vehicle speed profile such that the host vehicle 1 decelerates between the predetermined deceleration start position P0 and the deceleration switching position Pk at a primary deceleration Acoast, decelerates between the deceleration switching position Pk and the stop position Ps at a secondary deceleration Ath higher than the primary deceleration Acoast, and stops at the stop position Ps when the state of the object satisfies a predetermined stopping condition. As a result, the driving control device 100 pre-sets a deceleration switching position Pk at a predetermined switching determination distance Xa from the predetermined object, and therefore does not cause unnecessary secondary deceleration when the host vehicle 1 stops at the stop position Ps. Therefore, the driving control device 100 can switch the deceleration from the primary deceleration Acoast to the secondary deceleration Ath while reducing the possibility of disrupting the following traffic flow. Furthermore, by switching the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath at the deceleration switching position Pk, the driving control device 100 can reduce the discomfort felt by the occupants of the host vehicle 1 due to the deceleration of the host vehicle 1 and improve the riding comfort of the occupants of the host vehicle 1.

[0042] Furthermore, when the host vehicle 1 is traveling upstream of the deceleration start position P0, the processor 10 of the driving control device 100 determines whether the state of the object can be determined, and if the state of the object cannot be determined, starts executing driving control in accordance with the vehicle speed profile at the deceleration start position P0. That is, even if the detection device 101 cannot detect the state of the object, the host vehicle 1 starts deceleration at the primary deceleration rate Acoast after passing the deceleration start position P0. This allows the driving control device 100 to control the driving of the host vehicle 1 in advance so that the host vehicle 1 can stop at the stop position Ps when it is determined that the state of the object satisfies the stop condition.

[0043] Furthermore, the processor 10 of the driving control device 100 determines whether the state of the object satisfies the stop condition, and if the state of the object does not satisfy the stop condition, cancels the execution of driving control according to the vehicle speed profile. As a result, if the driving control device 100 determines that the state of the object does not satisfy the stop condition, it can control the driving of the host vehicle 1 so that the host vehicle 1 passes through the intersection T without stopping at the stop position Ps.

[0044] Furthermore, the processor 10 of the driving control device 100 determines whether the state of the object satisfies the stopping condition when the host vehicle 1 passes through the deceleration switching position Pk, and if the state of the object satisfies the stopping condition, switches the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath. This allows the driving control device 100 to control the vehicle speed of the host vehicle 1 by determining whether to switch the deceleration of the host vehicle 1 from the primary deceleration Acoast to the secondary deceleration Ath when the host vehicle 1 passes through the deceleration switching position Pk.

[0045] The processor 10 of the driving control device 100 also sets the secondary deceleration Ath based on the switching distance Xth between the deceleration switching position Pk and the stop position Ps. As shown in FIGS. 3 and 4, the secondary deceleration Ath is set so that the secondary deceleration Ath corresponding to the second switching distance Xth2, which is shorter than the first switching distance Xth1, is higher than the secondary deceleration Ath corresponding to the first switching distance Xth1. That is, the shorter the switching distance Xth, the higher the secondary deceleration Ath is set. This allows the driving control device 100 to appropriately set the secondary deceleration Ath according to the stop position Ps without changing the deceleration switching position Pk. That is, as shown in FIG. 2, the longer the distance Xc between the object (traffic light B1) and the stop position Ps, the shorter the switching distance Xth, and therefore the higher the secondary deceleration Ath is set.

[0046] Furthermore, the processor 10 of the driving control device 100 sets the secondary deceleration Ath with a predetermined secondary deceleration upper limit value Alim as the upper limit, thereby enabling the driving control device 100 to suppress sudden deceleration of the vehicle 1, reduce the discomfort felt by the occupants of the vehicle 1 during deceleration, and reduce the impact of the deceleration of the vehicle 1 on the following traffic flow.

[0047] The processor 10 of the driving control device 100 sets a switching vehicle speed Vth, which is the vehicle speed of the host vehicle 1 at the deceleration switching position Pk, based on the switching distance Xth between the deceleration switching position Pk and the stop position Ps. As shown in FIGS. 3 and 4, the switching vehicle speed Vth is set so that the switching vehicle speed Vth corresponding to the second switching distance Xth2, which is shorter than the first switching distance Xth1, is lower than the switching vehicle speed Vth corresponding to the first switching distance Xth1. That is, the shorter the switching distance Xth, the lower the switching vehicle speed Vth is set. This allows the driving control device 100 to appropriately set the switching vehicle speed Vth according to the stop position Ps without changing the deceleration switching position Pk. That is, as shown in FIG. 2, the longer the distance Xc between the object (traffic light B1) and the stop position Ps, the shorter the switching distance Xth, and therefore the lower the switching vehicle speed Vth is set.

[0048] The processor 10 of the driving control device 100 sets the switching vehicle speed Vth with a predetermined vehicle speed upper limit value Vlim as the upper limit. This allows the driving control device 100 to prevent the switching vehicle speed Vth from becoming too high when the switching distance Xth is long. Furthermore, by setting the vehicle speed upper limit value Vlim lower than the vehicle speed limit (initial vehicle speed Vnow), the driving control device 100 can prevent the switching vehicle speed Vth from becoming equal to or higher than the vehicle speed limit (initial vehicle speed Vnow). This allows the vehicle 1 to decelerate between the deceleration start position P0 and the deceleration switching position Pk at the primary deceleration rate Acoast, even when the switching distance Xth is long.

[0049] The processor 10 of the driving control device 100 calculates a virtual deceleration Ax assuming that the host vehicle 1 decelerates at a constant virtual deceleration Ax between the deceleration start position P0 and the stop position Ps and stops at the stop position Ps. If the virtual deceleration Ax is higher than the secondary deceleration upper limit value Alim, the processor 10 regenerates the vehicle speed profile so that the host vehicle 1 decelerates at the virtual deceleration Ax between the deceleration start position P0 and the stop position Ps. As a result, if the intersection passage determination unit 11 is late in determining that the host vehicle 1 has passed through the intersection T, or if the secondary deceleration determination unit 14 is late in determining to switch the vehicle speed profile, the driving control device 100 can reliably stop the host vehicle 1 at the stop position Ps by rapidly decelerating the host vehicle 1 at the virtual deceleration Ax.

[0050] Furthermore, if the virtual deceleration Ax is higher than the maximum deceleration Amax and the degree of fulfillment of the stop condition is equal to or lower than a predetermined value, the processor 10 of the driving control device 100 cancels the execution of driving control according to the vehicle speed profile. That is, if the virtual deceleration Ax is higher than the maximum deceleration Amax and the degree of fulfillment of the stop condition is equal to or lower than a predetermined value, the host vehicle 1 passes through the stop position Ps at the initial vehicle speed Vnow at the deceleration start position P0. As a result, if the host vehicle 1 cannot stop at the stop position Ps even when decelerating at the maximum deceleration Amax, the driving control device 100 allows the host vehicle 1 to smoothly pass through the stop position Ps and the intersection T without decelerating, provided that the degree of fulfillment of the stop condition is equal to or lower than a predetermined value.

[0051] Furthermore, the switching determination distance Xa is the distance at which the detection device 101 of the host vehicle 1 can recognize an object (traffic light B1). This allows the driving control device 100 to set the switching determination distance Xa according to the performance of the detection device 101. Specifically, the higher the performance of the detection device 101, the longer the driving control device 100 can set the switching determination distance Xa. In other words, the driving control device 100 can generate a vehicle speed profile according to the performance of the detection device 101. Note that the "distance at which the detection device 101 of the host vehicle 1 can recognize an object" may be the upper limit of the distance at which the detection device 101 can recognize an object, or may be a distance shorter than the upper limit of the distance at which the detection device 101 can recognize an object. Furthermore, the "distance at which the detection device 101 of the host vehicle 1 can recognize an object" may change not only based on the performance of the detection device 101 but also based on the driving environment, such as weather.

[0052] The processor 10 of the driving control device 100 also sets a deceleration start position P0 based on the switching determination distance Xa. As shown in Figures 3 and 4, the deceleration start position P0 is set so that a deceleration start position P02 corresponding to a second switching determination distance Xa2, which is shorter than the first switching determination distance Xa1, is located downstream of a deceleration start position P01 corresponding to the first switching determination distance Xa1. This allows the driving control device 100 to set a section (a section between the deceleration start position P0 and the deceleration switching position Pk) in which the host vehicle decelerates at the primary deceleration Acoast, based on the switching determination distance Xa.

[0053] Furthermore, the object whose state is to be detected by the detection device 101 is a traffic light B1 provided at the intersection T. Furthermore, the stop condition is that the traffic light B1 is displaying a stop signal, or that the detection device 101 of the host vehicle 1 is unable to detect the signal displayed by the traffic light. As a result, when the traffic light B1 at the intersection T is displaying a stop signal (when the traffic light color is red), or when the detection device 101 is unable to detect the signal displayed by the traffic light due to bad weather, a malfunction of the traffic light B1, a road shape such as a curve, or obstruction by a large vehicle, the driving control device 100 can decelerate the host vehicle 1 in two stages, using a primary deceleration Acoast and a secondary deceleration Ath, and stop the host vehicle 1 at a stop position Ps.

[0054] The object whose state is to be detected by the detection device 101 is not limited to a traffic light B1, but may also be a crosswalk B2 that intersects with the travel route R of the host vehicle 1, as shown in FIG. 7 . When the object is the crosswalk B2, the stopping condition is that a moving object M, such as a pedestrian, is present on the crosswalk B2, or that the detection device 101 of the host vehicle 1 is unable to detect the presence or absence of the moving object M on the crosswalk B2. The moving object M is not limited to a pedestrian, but may also be a bicycle, a wheelchair, or the like. As a result, when the moving object M is passing through the crosswalk B2 at the intersection T, or when the detection device 101 is unable to detect the presence or absence of the moving object M on the crosswalk B2, the driving control device 100 can decelerate the host vehicle 1 in two stages, using a primary deceleration Acoast and a secondary deceleration Ath, and stop the host vehicle 1 at a stop position Ps on the upstream side of the intersection T. The detection device 101 may be unable to detect the presence or absence of the moving object M on the crosswalk B2 due to, for example, bad weather, a road shape such as a curve, or obstruction by a large vehicle.

[0055] 2 and 7, when the state of the object satisfies the stop condition, the driving control device 100 decelerates the host vehicle 1 in two stages, using a primary deceleration Acoast and a secondary deceleration Ath. However, this is not limited to this, and the driving control device 100 may decelerate the host vehicle 1 in three stages, as shown in FIGS. 8 and 9. Specifically, the primary deceleration Acoast includes a low primary deceleration Acoast1 and a high primary deceleration Acoast2 that is higher than the low primary deceleration Acoast1. Furthermore, as shown in FIG. 8, the vehicle speed profile generator 13 sets an intermediate deceleration switching position Pkm between the deceleration start position P0 and the deceleration switching position Pk. The distance between the stop position Ps and the intermediate deceleration switching position Pkm is an intermediate switching distance Xm. 9, the primary deceleration profile generation unit 131 of the vehicle speed profile generation unit 13 generates a low primary deceleration profile G11 for decelerating the host vehicle 1 at a low primary deceleration rate Acoast1 and a high primary deceleration profile G12 for decelerating the host vehicle 1 at a high primary deceleration rate Acoast2. When the state of the object satisfies the stop condition, the vehicle speed profile generation unit 13 generates the vehicle speed profile so that the primary deceleration rate Acoast switches from the low primary deceleration rate Acoast1 to the high primary deceleration rate Acoast2 at the timing when the host vehicle 1 passes through the intermediate deceleration rate switching position Pkm.

[0056] The driving control device 100 may set a plurality of intermediate deceleration switching positions Pkm between the deceleration start position P0 and the deceleration switching position Pk, and decelerate the host vehicle 1 in four or more stages. In this case, the primary deceleration Acoast is made up of three or more decelerations, and the vehicle speed profile generator 13 generates a vehicle speed profile such that the primary deceleration Acoast switches from a predetermined deceleration to a deceleration higher than the predetermined deceleration at the timing when the host vehicle 1 passes through each of the intermediate deceleration switching positions Pkm.

[0057] In this way, the driving control device 100 may set one or more intermediate deceleration switching positions Pkm between the deceleration start position P0 and the deceleration switching position Pk, and generate a vehicle speed profile such that the primary deceleration Acoast switches from a predetermined deceleration to a deceleration higher than the predetermined deceleration when the host vehicle 1 passes through each of the intermediate deceleration switching positions Pkm. This allows the driving control device 100 to switch the primary deceleration Acoast of the host vehicle 1 once or multiple times between the deceleration start position P0 and the deceleration switching position Pk. In other words, the driving control device 100 can switch the deceleration of the host vehicle 1 through three or more stages before stopping the host vehicle 1 at the stop position Ps. This allows the driving control device 100 to decelerate the host vehicle 1 more smoothly, reducing the discomfort felt by occupants of the host vehicle 1 due to deceleration and improving the ride comfort of the occupants. [Explanation of symbols]

[0058] 100...Operation control device 1...Own vehicle 10...Processor 13...Vehicle speed profile generation unit 111...Deceleration switching position setting unit 112...Stop position acquisition unit 114...Intersection detection unit Acoast…1st deceleration Ath…Secondary deceleration Ax: Virtual deceleration Alim: Upper limit of secondary deceleration B1...Object (traffic light) B2: Object (crosswalk) M…moving object T…Intersection P0…Deceleration start position Pk...Deceleration switching position Pkm...Intermediate deceleration switching position Ps…stop position Vth: Switching vehicle speed Vnow…Initial vehicle speed Vlim: Maximum vehicle speed Xa...Switching judgment distance Xth: Switching distance

Claims

1. A driving control method for generating a vehicle speed profile of a host vehicle using a processor, comprising: The processor: determining whether an intersection exists downstream of the vehicle; If the intersection exists, the stop position on the upstream side of the intersection is acquired; generating the vehicle speed profile so that the host vehicle decelerates at a predetermined primary deceleration from a predetermined deceleration start position located upstream of a distance at which a detection device of the host vehicle can recognize a predetermined object at the intersection, decelerates at a secondary deceleration higher than the primary deceleration from a deceleration switch position located at an upper limit value of the distance at which the detection device of the host vehicle can recognize the object, and stops at the stop position; A driving control method for switching the deceleration of the host vehicle from the primary deceleration to the secondary deceleration when the detection device of the host vehicle cannot detect the object.

2. The processor:

2. The driving control method according to claim 1, wherein, when the host vehicle is traveling upstream of the deceleration start position and the detection device cannot detect the object, execution of driving control according to the vehicle speed profile is started at the deceleration start position.

3. The processor: determining whether the state of the object satisfies a predetermined stopping condition; 3. The driving control method according to claim 1, further comprising: canceling execution of driving control according to the vehicle speed profile when the state of the object does not satisfy the stop condition.

4. The processor: determining whether or not a state of the object satisfies a predetermined stop condition at a timing when the host vehicle passes the deceleration switching position; 4. The driving control method according to claim 1, wherein the deceleration of the host vehicle is switched from the primary deceleration to the secondary deceleration when the state of the object satisfies the stop condition.

5. the processor sets the secondary deceleration based on a switching distance between the deceleration switching position and the stop position; The driving control method according to any one of claims 1 to 4, wherein the secondary deceleration is set so that the secondary deceleration corresponding to a second switching distance that is shorter than the first switching distance is higher than the secondary deceleration corresponding to a first switching distance.

6. The processor:

6. The operation control method according to claim 1, wherein the secondary deceleration is set with a predetermined secondary deceleration upper limit value as an upper limit.

7. the processor sets a switching vehicle speed, which is the vehicle speed of the host vehicle 1 at the deceleration switching position, based on a switching distance between the deceleration switching position and the stop position; The driving control method according to any one of claims 1 to 6, wherein the switching vehicle speed is set so that the switching vehicle speed corresponding to a second switching distance that is shorter than the first switching distance is lower than the switching vehicle speed corresponding to a first switching distance.

8. The processor: The driving control method according to claim 7 , wherein the switching vehicle speed is set with a predetermined vehicle speed upper limit value as an upper limit.

9. The processor: calculating a virtual deceleration when it is assumed that the host vehicle decelerates at a constant virtual deceleration between the deceleration start position and the stop position and stops at the stop position; 7. The driving control method according to claim 6, wherein, when the virtual deceleration is higher than the secondary deceleration upper limit value, the vehicle speed profile is regenerated so that the host vehicle decelerates at the virtual deceleration between the deceleration start position and the stop position.

10. The processor:

10. The driving control method according to claim 9, wherein, when the virtual deceleration is higher than a predetermined maximum deceleration and a degree of fulfillment of a predetermined stop condition is equal to or less than a predetermined value, execution of the driving control according to the vehicle speed profile is canceled.

11. The driving control method according to any one of claims 1 to 10, wherein the deceleration start position is set so that the deceleration start position corresponding to a second switching determination distance, which is shorter than the first switching determination distance, is located downstream of the deceleration start position corresponding to a first switching determination distance.

12. the primary deceleration includes a plurality of decelerations, The processor: one or more intermediate deceleration switching positions are set between the deceleration start position and the deceleration switching position; The driving control method according to any one of claims 1 to 11, wherein the vehicle speed profile is generated so that the primary deceleration is switched from a predetermined deceleration to a deceleration higher than the predetermined deceleration at a timing when the host vehicle passes through each of the intermediate deceleration switching positions.

13. the object is a traffic light provided at the intersection, 11. A driving control method according to claim 3, wherein the stop condition is that the traffic light is displaying a stop signal or that a detection device of the vehicle is unable to detect the signal displayed by the traffic light.

14. the object is a crosswalk that intersects with the travel path of the host vehicle, 11. The driving control method according to claim 3, wherein the stopping condition is that a moving object is present at the crosswalk, or that a detection device of the vehicle is unable to detect the presence or absence of a moving object at the crosswalk.

15. A driving control device that generates a vehicle speed profile of a host vehicle, an intersection determination unit that determines whether an intersection exists downstream of the host vehicle; a stop position acquisition unit that acquires a stop position on an upstream side of the intersection when the intersection exists; a vehicle speed profile generation unit that generates the vehicle speed profile so that the host vehicle decelerates at a predetermined primary deceleration from a predetermined deceleration start position located upstream of a distance at which a detection device of the host vehicle can recognize a predetermined object at the intersection, decelerates at a secondary deceleration higher than the primary deceleration from a deceleration switch position located at an upper limit value of the distance at which the detection device of the host vehicle can recognize the object, and stops at the stop position; a vehicle speed profile switching unit that switches the deceleration of the host vehicle from the primary deceleration to the secondary deceleration when the detection device of the host vehicle cannot detect the object.

Images