Image control device, image control method, and recording medium

Abstract

The image control device (10) comprises: a first obtaining unit (11) for obtaining the position of a vehicle measured and located by a satellite positioning system; a second obtaining unit (12) for obtaining the estimated position of the vehicle estimated based on a dead reckoning algorithm; a heading deviation estimating unit (13) for estimating the deviation of the vehicle's heading based on the position of the vehicle measured and located by the satellite positioning system and the estimated position of the vehicle estimated based on the dead reckoning algorithm; a heading calculating unit (14) for calculating the estimated heading of the vehicle based on the deviation of the estimated vehicle's heading; and an output unit (15) for outputting the estimated heading of the vehicle to an image display device (60) for displaying information based on the vehicle's heading.

Description

Technical Field

[0001] The present disclosure relates to an image control device, an image control method, and a recording medium. Background Art

[0002] Patent Documents 1 and 2 disclose technologies for detecting the vehicle's own position using map data and a GPS (Global Positioning System) and displaying route information to a destination in the user's field of view via a head-up display (hereinafter also referred to as HUD).

[0003] (Prior art literature)

[0004] (Patent Document)

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 7-257228

[0006] Patent Document 2: Japanese Patent Application Publication No. 2018-045103

[0007] The route information to the destination displayed by an image display device such as a HUD may include information based on the vehicle's orientation (the direction of the vehicle itself) for guiding the vehicle to the destination. Information based on the vehicle's orientation may include, for example, an arrow extending from the vehicle itself in the direction of travel (see the following). Figure 9 ) etc. To generate information based on the vehicle's position, the vehicle's position must be estimated. However, if the estimated vehicle position deviates from the actual vehicle position, this may cause passengers viewing the information based on the vehicle's position to feel strange. For example, an arrow extending from the vehicle itself in the direction of travel may appear to be off the road due to a discrepancy in the estimated vehicle's position. Summary of the Invention

[0008] Therefore, the present disclosure provides an image control device and the like that can improve the accuracy of estimating the direction of a vehicle.

[0009] One embodiment of the present disclosure relates to an image control device comprising: a first obtaining unit for obtaining a position of a vehicle measured and located by a satellite positioning system; a second obtaining unit for obtaining an estimated position of the vehicle estimated based on a dead reckoning algorithm; a heading deviation estimating unit for estimating a deviation in the vehicle's heading based on the position of the vehicle measured and located by the satellite positioning system and the estimated position of the vehicle estimated based on the dead reckoning algorithm; a heading calculating unit for calculating an estimated heading of the vehicle based on the deviation in the estimated vehicle heading; and an output unit for outputting the estimated heading of the vehicle to an image display device for displaying information based on the vehicle's heading.

[0010] Furthermore, one aspect of the present disclosure relates to an image control method that obtains a position of a vehicle measured and located by a satellite positioning system, obtains an estimated position of the vehicle estimated based on a dead reckoning algorithm, estimates a deviation in the vehicle's orientation based on the position of the vehicle measured and located by the satellite positioning system and the estimated position of the vehicle estimated based on the dead reckoning algorithm, calculates an estimated orientation of the vehicle based on the estimated orientation deviation, and outputs the estimated orientation of the vehicle to an image display device that displays information based on the vehicle's orientation.

[0011] Furthermore, a recording medium according to one aspect of the present disclosure is a computer-readable recording medium having recorded thereon a program for causing a computer to execute the above-described image control method.

[0012] The image control device and the like of the present disclosure can improve the accuracy of estimating the direction of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a block diagram showing an example of the configuration of a video control device and its peripheral devices according to an embodiment.

[0014] Figure 2 This is a diagram for explaining a method of calculating the orientation of a vehicle using a gyro sensor.

[0015] Figure 3 This is a diagram for explaining the updating of the zero point of the gyro sensor.

[0016] Figure 4 This is a flowchart showing an example of the operation of the image control device according to the embodiment.

[0017] Figure 5 This is a diagram showing an example of a method for estimating a deviation in the orientation of a vehicle according to the embodiment.

[0018] Figure 6This is a diagram showing another example of a method for estimating a deviation in the orientation of a vehicle according to the embodiment.

[0019] Figure 7 This is a diagram for explaining a method of eliminating drawing delay according to an embodiment.

[0020] Figure 8 This is a diagram showing the transition of the deviation in the orientation when the image control device according to the embodiment is applied.

[0021] Figure 9 This is a diagram showing an example of display on a video display device. DETAILED DESCRIPTION

[0022] (Implementation Method)

[0023] Hereinafter, an image control device and the like according to the embodiments will be described with reference to the accompanying drawings.

[0024] Figure 1 1 is a block diagram showing an example of the configuration of the video control device 10 and its peripheral devices according to the embodiment. Figure 1 , in addition to the image control device 10, an information processing device 20, an ECU 30, a gyro sensor 40, an acceleration sensor 50, and an image display device 60 are shown. These devices are mounted on a vehicle (eg, an automobile), for example.

[0025] The information processing device 20 is a device that can obtain information such as the position of the vehicle and the orientation of the vehicle, which are located and measured by a satellite positioning system such as GPS (Global Positioning System), as well as information on the path to the vehicle's destination (such as the shortest path to the destination or a path that avoids traffic jams, etc.), such as a car navigation system.

[0026] The ECU 30 is an ECU that processes a vehicle speed signal, for example, and is a device that can output the current vehicle speed to a CAN (Controller Area Network) bus.

[0027] The gyro sensor 40 detects the yaw rate information of the vehicle and outputs the detection result. By integrating the detection results, the direction of the vehicle can be calculated.

[0028] The acceleration sensor 50 is a sensor that detects the acceleration of the vehicle and outputs a detection result. Based on the detection result, it can be determined whether the vehicle is stopped.

[0029] The image display device 60 is a device that displays information based on the vehicle's position, such as a HUD, an electronic mirror, or a car navigation system. In this embodiment, the image display device 60 is a HUD. The information based on the vehicle's position, such as an arrow mark extending from the vehicle as the starting point to the direction of travel (see below), is displayed. Figure 9 The image display device 60 displays information based on the vehicle's position based on the information about the route to the vehicle's destination obtained from the information processing device 20 and the estimated vehicle position obtained from the image control device 10. The information based on the vehicle's position may be the vehicle's position itself. In other words, the vehicle's position can be displayed on the image display device 60.

[0030] The image control device 10 calculates the estimated vehicle heading and outputs the estimated heading to the image display device 60. The display content (information based on the vehicle's heading) on the image display device 60 changes according to the estimated heading calculated by the image control device 10. Therefore, the image control device 10 can also be said to control the display content of the image display device 60. The image control device 10 includes a first acquisition unit 11, a second acquisition unit 12, a heading deviation estimation unit 13, a heading calculation unit 14, and an output unit 15. The image control device 10 is a computer that includes a processor, memory, and communication circuits. The memory, such as ROM (Read Only Memory) or RAM (Random Access Memory), can store programs executed by the processor. Information obtained by the image control device 10 is also stored in the memory. For example, the processor operates according to the program to implement the functions of the first acquisition unit 11, the second acquisition unit 12, the heading deviation estimation unit 13, the heading calculation unit 14, and the output unit 15.

[0031] The first acquisition unit 11 acquires the position of the vehicle as measured by a satellite positioning system. Specifically, the first acquisition unit 11 acquires the position of the vehicle as measured by a satellite positioning system from the information processing device 20. The first acquisition unit 11 acquires a first position, which is the position of the vehicle as measured by a satellite positioning system, and a second position, which is the position of the vehicle as measured by the satellite positioning system when the vehicle moves from the first position. By sequentially acquiring the positions of the vehicle as measured by the satellite positioning system, the first acquisition unit 11 can estimate the vehicle's travel trajectory from the first position to the second position.

[0032] The second obtaining unit 12 obtains an estimated vehicle position estimated based on dead reckoning. For example, the second obtaining unit 12 estimates the vehicle's estimated position at the time the second position was measured (specifically, the timing of the second position measurement) based on dead reckoning, a method that uses the first position, the vehicle's orientation at the first position, detection results from the vehicle's gyro sensor 40, and vehicle speed information to obtain the vehicle's estimated position. Unlike satellite positioning systems, which directly measure position, dead reckoning is a technique that uses the orientation of a moving object at a certain location, detection results from a gyro sensor at that location, and speed information to relatively measure the position of the moving object. The second obtaining unit 12 can estimate the vehicle's trajectory from the first position to the estimated position based on dead reckoning.

[0033] When the first position obtained by the first obtaining unit 11 and the first position obtained by the second obtaining unit are the same, the second obtaining unit 12 may obtain the first position from the information processing device 20 or from the first obtaining unit 11. Furthermore, the second obtaining unit 12 obtains the vehicle's position at the first position from the information processing device 20, for example, when the vehicle starts (starts traveling). In other words, the vehicle's position at the first position obtained by the second obtaining unit 12 when the vehicle starts traveling is the vehicle's position measured using a satellite positioning system. Furthermore, the second obtaining unit 12 obtains the vehicle's position at the first position from the position calculation unit 14, for example, after the vehicle starts traveling. Furthermore, the second obtaining unit 12 obtains the detection results of the gyro sensor 40 from the gyro sensor 40 and obtains vehicle speed information from the ECU 30 via a CAN bus or the like. Furthermore, the second obtaining unit 12 receives notification of the timing of the second position measurement from the first obtaining unit 11, for example.

[0034] Here use Figure 2 A method of calculating the vehicle's orientation based on the detection results of the gyro sensor 40 will be described.

[0035] Figure 2 This is a diagram for explaining a method of calculating the orientation of the vehicle using the gyro sensor 40 .

[0036] For example, assume that the vehicle's orientation at time T = 0 (initial orientation) is known. By adding the cumulative value of the detection results (in other words, the yaw angular velocity) of the gyro sensor 40 between time T = 0 and time T = 1 to the initial orientation, the vehicle's orientation at time T = 1 can be calculated. By adding the cumulative value of the detection results of the gyro sensor 40 between time T = 1 and time T = 2 to the vehicle's orientation at time T1, the vehicle's orientation at time T = 2 can be calculated. In this way, when the vehicle's orientation at a certain moment is known, the vehicle's orientation at that moment and the cumulative value of the detection results of the gyro sensor 40 can be accurately calculated. However, if the initial orientation includes a deviation, the subsequent vehicle orientation calculated using the initial orientation will also deviate from the deviation of the initial orientation.

[0037] In addition, even when the vehicle is stopped, the zero point of the gyro sensor 40 (the output of the gyro sensor 40 when the vehicle is stopped) may not be zero due to gyro drift. In this case, the accumulated value of the gyro sensor 40 also deviates. Therefore, the zero point of the gyro sensor 40 is updated. Figure 3 To explain.

[0038] Figure 3 1 is a diagram for explaining the updating of the zero point of the gyro sensor 40 .

[0039] like Figure 3 As shown, as the vehicle continues to travel, the zero point of the gyro sensor 40 begins to shift from zero at a certain point due to gyro drift. This shift in the zero point of the gyro sensor 40 causes the cumulative value of the detection results of the gyro sensor 40 to change. Therefore, due to the shift in the zero point of the gyro sensor 40 (in other words, due to gyro drift), the vehicle's orientation calculated using the gyro sensor 40 deviates. Therefore, for example, the second acquisition unit 12 updates the zero point. Specifically, when the vehicle stops (for example, when the vehicle speed over the past three seconds is zero and the change in the vehicle's acceleration is below a predetermined threshold), the second acquisition unit 12 sets the average value of the detection results of the gyro sensor 40 over the past three seconds to zero, thereby updating the zero point. This prevents the vehicle's orientation from deviating further. The second acquisition unit 12 obtains the vehicle's acceleration from the acceleration sensor 50. For example, when the vehicle is stopped, the second obtaining unit 12 does not update the zero point if the average value of the detection results of the gyro sensor 40 over the past three seconds is zero (in other words, the zero point has not changed). In other words, the second obtaining unit 12 updates the zero point when a change in the zero point is detected.

[0040] Here back Figure 1As described above, the heading deviation estimating unit 13 estimates the deviation in the vehicle's heading based on the vehicle's position measured by a satellite positioning system and the vehicle's estimated position estimated by dead reckoning. Details of the operation of the heading deviation estimating unit 13 will be described later.

[0041] The direction calculation unit 14 calculates the estimated direction of the vehicle based on the deviation of the vehicle's direction estimated by the direction deviation estimation unit 13. The operation of the direction calculation unit 14 will be described in detail later.

[0042] The output unit 15 outputs the estimated direction of the vehicle to the image display device 60 .

[0043] Next, the operation of the image control device 10 will be described.

[0044] Figure 4 This is a flowchart showing an example of the operation of the image control device 10 according to the embodiment.

[0045] The first obtaining unit 11 obtains the position of the vehicle measured and located by the satellite positioning system (step S11). Specifically, the first obtaining unit 11 obtains the first position of the vehicle measured and located by the satellite positioning system, and the second position of the vehicle measured and located by the satellite positioning system when the vehicle moves from the first position.

[0046] The second obtaining unit 12 obtains an estimated position of the vehicle estimated based on dead reckoning (step S12). The estimated position of the vehicle is the position of the vehicle when positioning and measuring at the second position, estimated based on dead reckoning using the first position, the orientation of the vehicle at the first position, the detection results of the gyro sensor 40 included in the vehicle, and the vehicle's speed information.

[0047] The orientation deviation estimating unit 13 estimates the orientation deviation of the vehicle based on the position of the vehicle measured and located by the satellite positioning system and the estimated position of the vehicle estimated based on the dead reckoning algorithm (step S13). Specifically, the orientation deviation estimating unit 13 estimates the orientation deviation of the vehicle based on the first position of the vehicle, the second position of the vehicle, and the estimated position of the vehicle. The first position of the vehicle is the position measured and located by the satellite positioning system. The second position of the vehicle is the position measured and located by the satellite positioning system when the vehicle moves from the first position. The estimated position of the vehicle is the estimated position of the vehicle when it is measured and located at the second position based on the dead reckoning algorithm. The dead reckoning algorithm is a method that uses the first position, the orientation of the vehicle at the first position, the detection result of the gyro sensor of the vehicle, and the speed information of the vehicle. The method for estimating the orientation deviation of the vehicle utilizes Figure 5Let's explain in detail.

[0048] Figure 5 FIG. 1 is a diagram showing an example of a method for estimating a deviation in the orientation of a vehicle according to an embodiment. Figure 5 The vehicle's trajectory on the horizontal plane is schematically shown in FIG. 1 , assuming that the vehicle moves from the lower left side (origin side) to the upper right side (positive side of the X-axis and Y-axis). Figure 5 The solid line in represents an actual driving trajectory. Although the image control device 10 and the like cannot recognize this driving trajectory, it is shown in the figure for comparison with the driving trajectory of the satellite positioning system and the driving trajectory of the dead reckoning method. Figure 5 The dotted line in the figure represents the driving trajectory measured by the satellite positioning system. Figure 5 The dotted line in represents the estimated driving trajectory based on the dead reckoning algorithm.

[0049] Figure 5 Position A1 in the figure represents the first position measured by the satellite positioning system, and position A2 represents the second position measured by the satellite positioning system when the vehicle has moved from position A1. The image control device 10 sequentially obtains the vehicle's position measured by the satellite positioning system, thereby identifying the vehicle's trajectory based on the satellite positioning system. However, the vehicle's position measured by the satellite positioning system contains errors and may deviate by approximately 10 meters from the actual driving position.

[0050] Figure 5 Position B1 in the figure represents the estimated position estimated based on the dead reckoning algorithm when the position A2 is positioned and measured. The image control device 10 obtains the orientation (initial orientation) of the vehicle at position A1, and sequentially obtains the detection results of the gyro sensor 40 at position A1 and the speed information of the vehicle at position A1, thereby being able to identify the driving trajectory based on the dead reckoning algorithm. When the dead reckoning algorithm is performed with high precision, the changes in the orientation of the vehicle at a certain location and the changes in the speed of the vehicle can be accurately reflected on the driving trajectory, so it can be seen that Figure 5It can be seen that the shape of the driving trajectory calculated using dead reckoning is similar to the actual driving trajectory. However, if the initial vehicle orientation used in dead reckoning deviates from the actual vehicle orientation, the position of the driving trajectory estimated by dead reckoning will deviate from the actual position of the driving trajectory by the amount of this deviation. Position A1 is the position at which the process of estimating the deviation in the vehicle orientation begins, for example, the starting position of vehicle travel (the vehicle's starting position) or the updated position of the zero point of gyro sensor 40. If Position A1 is the starting position of vehicle travel, the initial orientation is, for example, the vehicle orientation measured using a satellite positioning system. Because the accuracy of the vehicle orientation measured using a satellite positioning system is low, there is a high probability that the initial orientation deviates from the actual vehicle orientation. Furthermore, if Position A1 is the updated position of the zero point of gyro sensor 40, the initial orientation is, for example, the vehicle orientation calculated based on the detection results of gyro sensor 40. The zero point of the gyro sensor 40 is updated when the zero point of the gyro sensor 40 changes. Therefore, when the zero point of the gyro sensor 40 is updated, the vehicle orientation (in other words, the initial orientation) calculated based on the detection result of the gyro sensor 40 is likely to deviate from the actual vehicle orientation.

[0051] Assume that the zero point of gyro sensor 40 is updated at the vehicle's starting position or at the zero point update position of gyro sensor 40, and that the zero point of gyro sensor 40 does not change. Furthermore, assume that the vehicle is stopped at these positions, and that after the vehicle begins moving from these positions, there is no temporary change in the zero point of gyro sensor 40 due to gyro drift. Thus, while the vehicle moves from position A1, measured by the satellite positioning system, to position A2, the deviation in the vehicle's orientation is assumed to remain constant, except for the deviation at position A1.

[0052] When dead reckoning is performed with high accuracy to estimate the vehicle's heading deviation during movement, assuming the vehicle's heading deviation remains constant, the angle formed by the line connecting positions A1 and A2 and the line connecting positions A1 and B1 can be considered the vehicle's heading deviation. In other words, the heading deviation estimating unit 13 can estimate the vehicle's heading deviation based on positioning and measurement using a satellite positioning system or due to gyro drift.

[0053] Back to Figure 4As described above, the direction calculation unit 14 calculates the estimated vehicle direction based on the deviation in the vehicle direction estimated by the direction deviation estimation unit 13 (step S14). For example, the direction calculation unit 14 uses the deviation in the estimated vehicle direction to correct the vehicle direction calculated based on the detection results of the gyro sensor 40 during movement after position A2 (for example, by adding or subtracting the deviation in the vehicle direction), thereby calculating the estimated vehicle direction. This improves the accuracy of the vehicle direction estimation.

[0054] Then, the output unit 15 outputs the estimated vehicle orientation to the image display device 60 (step S15). Thus, the image display device 60 can display information based on the vehicle orientation based on the vehicle orientation with little deviation.

[0055] In addition, the direction deviation estimating unit 13 estimates the deviation of the vehicle's direction. After the estimated direction of the vehicle is calculated, it can continue to estimate the deviation of the vehicle's direction in sequence starting from position A1. This is because when estimating the deviation of the vehicle's direction, the longer the distance the vehicle moves, the higher the accuracy of the estimated deviation of the vehicle's direction. More details will be given later. Figure 6 However, the longer the vehicle moves without stopping, the more deviation in the vehicle's orientation occurs due to gyro drift (in other words, the change in the zero point of the gyro sensor 40). Therefore, when the zero point of the gyro sensor 40 changes and the zero point is updated, the deviation in the vehicle's orientation is estimated using the new first position as the starting point instead of position A1.

[0056] like Figure 5 As shown, the vehicle's position, as measured by a satellite positioning system, contains errors. The greater the error, the greater the deviation from the straight line connecting positions A1 and A2, thus reducing the accuracy of the estimated vehicle's heading deviation. On the other hand, the longer the distance between positions A1 and A2 (the distance the vehicle travels to estimate the vehicle's heading deviation), the less impact this error has on the estimated vehicle's heading deviation. However, the vehicle's heading deviation is calculated under the assumption that the dead reckoning algorithm is highly accurate and that the vehicle's heading deviation remains constant during movement. In reality, the longer the distance the vehicle travels, the lower the accuracy of the dead reckoning algorithm or the influence of gyroscope drift. Therefore, to maintain these assumptions, the distance the vehicle travels must be minimized.

[0057] Therefore, the bearing deviation estimation unit 13 can estimate the bearing of the vehicle in a short interval of about 10 meters, for example, and the bearing calculation unit 14 can calculate the estimated bearing of the vehicle based on the estimation results of the bearing of the vehicle in each interval. Specifically, the bearing deviation estimation unit 13 can estimate the deviation of the bearing of the vehicle in each of a plurality of consecutive intervals based on the first position, the second position, and the estimated position in each of a plurality of consecutive intervals. In addition, the bearing calculation unit 14 can calculate the estimated bearing of the vehicle based on the deviation of the bearing of the vehicle in two or more intervals among a plurality of consecutive intervals. In this regard, using Figure 6 To explain.

[0058] Figure 6 FIG. 1 is a diagram showing another example of a method for estimating a deviation in the orientation of a vehicle according to an embodiment. Figure 6 Zhongyu Figure 5 In the same way, the vehicle's trajectory on the horizontal plane is schematically represented, assuming that the vehicle moves from the lower left side (origin side) to the upper right side (positive side of the X-axis and Y-axis). Figure 6 In each of the multiple consecutive intervals (here, 3 intervals are shown as an example, i.e., from the 1st interval to the 3rd interval), there is a 1st position, a 2nd position, and an estimated position. In other words, using Figure 5 The processing of estimating the deviation of the vehicle's orientation based on the first position (position A1), the second position (position A2), and the estimated position (position B1) in the vehicle's position is performed in each of the first to third sections. In the first section, position A1 represents the first position measured by a satellite positioning system, position A2 represents the second position measured by a satellite positioning system when the vehicle has moved from position A1, and position B1 represents the estimated position estimated based on dead reckoning when position A2 is measured. Furthermore, in the second section, position A2 represents the first position measured by a satellite positioning system, position A3 represents the second position measured by a satellite positioning system when the vehicle has moved from position A2, and position B2 represents the estimated position estimated based on dead reckoning when position A3 is measured. In addition, in the third interval, position A3 represents the first position measured and located using the satellite positioning system, position A4 represents the second position measured and located using the satellite positioning system when the vehicle moves from position A3, and position B3 represents the estimated position estimated based on the dead reckoning algorithm when position A4 is measured and located.

[0059] While this example shows estimating the vehicle's heading deviation over three intervals, it is also possible to divide a distance of several hundred meters into shorter intervals of approximately 10 meters, and estimate the vehicle's heading deviation in each interval. Short intervals of approximately 10 meters facilitate high-precision dead reckoning and ensure that the vehicle's heading deviation remains constant during movement used to estimate the vehicle's heading deviation. However, the relatively short intervals are significantly affected by errors in the vehicle's position measured using a satellite positioning system, and the estimated vehicle heading deviation in each interval can easily increase. Furthermore, the distance between intervals is not limited to 10 meters; it can also be approximately 20 or 30 meters.

[0060] To this end, the position calculation unit 14 uses the deviation of the vehicle's position in two or more sections of the plurality of consecutive sections to reduce the influence of errors in the vehicle's position measured by the satellite positioning system. For example, by calculating the average or median of the vehicle's position in two or more sections, the accuracy of the estimated vehicle position can be further improved even when the estimated vehicle position in each section has a large deviation.

[0061] For example, the orientation calculation unit 14 can calculate the estimated orientation of the vehicle based on the average value of the deviation of the vehicle's orientation in each of multiple consecutive intervals excluding the following intervals, where the excluded intervals are intervals in which the vehicle's orientation changes by more than the first threshold value relative to the adjacent previous interval in multiple consecutive intervals, and the vehicle's orientation is the orientation calculated based on the detection results of the gyro sensor 40.

[0062] For example, in Figure 6In the example, of the adjacent first and second sections, the first section is the preceding section adjacent to the second section, and of the adjacent second and third sections, the second section is the preceding section adjacent to the third section. For example, in the adjacent first and second sections, the vehicle's orientation calculated based on the detection results of the gyro sensor 40 in the first section (the preceding section) is assumed to be north. Furthermore, the vehicle's orientation calculated based on the detection results of the gyro sensor 40 in the second section (the following section) is assumed to be east. In this case, for example, the vehicle's orientation changes by approximately 90 degrees within a distance of approximately 10 meters, and there is a high possibility that there may be sharp turns or left and right turns around the second section, resulting in a high possibility that the accuracy of the positioning measurement by the satellite positioning system or the accuracy of the dead reckoning method is insufficient. Therefore, it is possible to calculate an average value of the deviations in the vehicle's orientation in each of a plurality of consecutive intervals, excluding intervals in which the vehicle's orientation fluctuated by a first threshold value or more relative to the preceding interval, wherein the vehicle's orientation is calculated based on the detection results of the gyro sensor 40. By excluding deviations in the vehicle's orientation estimated in intervals where there is a high likelihood that the accuracy of the satellite positioning system's positioning measurement or the accuracy of the dead reckoning algorithm is insufficient, the accuracy of the estimated vehicle's orientation can be further improved. While the first threshold value has been described above as 90 degrees, the first threshold value is not particularly limited and can be set as appropriate.

[0063] In addition, for example, the direction calculation unit 14 can calculate the estimated direction of the vehicle based on the average value of the deviation of the vehicle's direction in each of multiple consecutive intervals excluding the following intervals, where the excluded intervals are intervals in which the deviation of the vehicle's direction is greater than the second threshold value among multiple consecutive intervals.

[0064] For example, in a certain interval among multiple consecutive intervals, the deviation of the estimated vehicle's orientation is sometimes large (for example, 20 degrees, etc.). In such an interval, the operation of the satellite positioning system becomes unstable, and there is a high possibility that the second position of the vehicle measured by the satellite positioning system deviates a lot from the actual position. Therefore, the average value of the deviation of the vehicle's orientation in each of the multiple consecutive intervals is calculated, excluding the following intervals. The excluded intervals are intervals in which the deviation of the vehicle's orientation is greater than the second threshold value among the multiple consecutive intervals. Since the deviation of the estimated vehicle's orientation in the interval where the possibility of the satellite positioning system's unstable operation is high is excluded, and the average value is calculated, the accuracy of the estimated vehicle's orientation can be further improved. In addition, the above describes an example in which the second threshold value is 20 degrees, but the second threshold value is not particularly limited and can be set appropriately.

[0065] In addition, the direction calculation unit 14 can calculate the estimated direction of the vehicle based on the average value of the deviation of the vehicle's direction in each of multiple consecutive intervals excluding the following two intervals: one of the excluded intervals is an interval in which the vehicle's direction changes by more than a first threshold value relative to the adjacent previous interval among multiple consecutive intervals, and the vehicle's direction is the direction calculated based on the detection result of the gyro sensor 40; the second excluded interval is an interval in which the deviation of the vehicle's direction is more than a second threshold value.

[0066] Alternatively, for example, the direction calculation unit 14 may calculate the estimated direction of the vehicle based on the median value of the deviations of the vehicle's direction in each of a plurality of consecutive sections.

[0067] The deviation of the vehicle's heading in intervals where the accuracy of the satellite positioning system's positioning measurements or the accuracy of the dead reckoning method is insufficient (for example, the intervals excluded from the average calculation described above) may sometimes be outliers relative to the deviation of the vehicle's heading in other intervals. When the average is calculated by including such outliers, the average is significantly affected by the outliers and may not be a normal value. Therefore, calculating the median value can further improve the accuracy of the estimated vehicle heading.

[0068] Alternatively, for example, the direction calculation unit 14 may calculate the estimated direction of the vehicle based on a weighted average of deviations in the direction of the vehicle in each of a plurality of consecutive sections.

[0069] For example, in an interval where the accuracy of the positioning measurement of the satellite positioning system or the accuracy of the dead reckoning method is insufficient (for example, an interval excluded when calculating the average value in the above description), the weight of the deviation of the vehicle's orientation is set to a relatively small value (for example, to 0.5, etc.) to calculate a weighted average value, thereby further improving the accuracy of the estimated vehicle's orientation.

[0070] The output unit 15 outputs the estimated position of the vehicle thus calculated to the image display device 60. However, when the image display device 60 displays information based on the position of the vehicle based on the estimated position of the vehicle, a rendering delay of, for example, approximately 33.3 ms occurs. In other words, in the image control device 10, even if the estimated position is calculated with high precision, information based on the position of the vehicle based on the estimated position of the vehicle approximately 33.3 ms ago is displayed on the image display device 60. Therefore, the output unit 15 can output the estimated position of the vehicle in the future, which is predicted based on the past change in the estimated position of the vehicle, to the image display device 60. In this regard, using Figure 7 To explain.

[0071] Figure 7This is a diagram for explaining a method of eliminating drawing delay according to an embodiment.

[0072] like Figure 7 As shown on the upper side of Figure 7 When the image display device 60 outputs the vehicle's position information based on the current estimated position (the dotted line in the image) to the image display device 60, the vehicle's position information based on the current estimated position is displayed on the image display device 60 approximately 33.3 ms later. However, the vehicle's position changes constantly, and sometimes the vehicle's position is different from the current position (in other words, approximately 33.3 ms after the current time) at the drawing time. Figure 7 The double-dashed line in the figure) will cause a deviation in the vehicle's orientation due to the drawing delay.

[0073] So, if Figure 7 As shown in the lower side of the figure, the output unit 15 does not output the estimated position of the vehicle as it is to the image display device 60, but predicts the estimated position of the vehicle in the future ( Figure 7 The image is output to the image display device 60 (the solid line in the figure). For example, the output unit 15 predicts the estimated vehicle position approximately 33.3 ms from now based on the change from approximately 16.6 ms ago to the present time. This reduces the difference between the predicted estimated position used in rendering and the estimated position at the time of rendering, minimizing the deviation in the vehicle's position due to rendering delays. In other words, information based on the vehicle's position is accurately displayed on the image display device 60.

[0074] Next, use Figure 8 The transition of the deviation in the orientation when the image control device 10 of this embodiment is applied will be described.

[0075] Figure 8 This diagram shows the transition of orientation deviation when the image control device 10 is applied according to the embodiment. For example, in this embodiment, the orientation deviation of the vehicle is estimated and corrected, thereby reducing the overall orientation error of the vehicle.

[0076] like Figure 8 As shown, the vehicle's orientation is estimated by accumulating the detection results of the gyro sensor 40 at a frequency equivalent to the 60 Hz rendering rate, for example. For example, the vehicle's orientation measured using a satellite positioning system is used as the initial orientation when the vehicle is started. The vehicle's orientation measured using a satellite positioning system has low accuracy. Until the deviation in the vehicle's orientation is estimated and the vehicle's orientation is corrected, the vehicle's orientation calculated based on the detection results of the gyro sensor 40 includes errors in the initial orientation.

[0077] After the vehicle begins moving, the vehicle's orientation deviation is estimated based on the vehicle's position measured by a satellite positioning system and the estimated vehicle position estimated using dead reckoning. The vehicle's orientation is then corrected based on the estimated orientation deviation. This allows the vehicle's orientation error to be reduced to, for example, 0.8 degrees or less.

[0078] If the vehicle continues to travel for a certain distance, the deviation in the vehicle's orientation may increase due to gyro drift. Therefore, the vehicle is temporarily stopped, and the zero point of gyro sensor 40 is corrected to prevent the deviation in the vehicle's orientation from increasing. The deviation in the vehicle's orientation is then estimated again based on the vehicle's position measured by the satellite positioning system and the estimated position estimated using dead reckoning. The vehicle's orientation is corrected based on the estimated deviation in the vehicle's orientation. This allows the error in the vehicle's orientation to be reduced to less than 0.8 degrees. If the zero point of gyro sensor 40 subsequently shifts, for example, and the zero point of gyro sensor 40 is corrected, the vehicle's orientation deviation is estimated to minimize the error.

[0079] As described above, by improving the accuracy of the estimation of the vehicle's orientation, information based on the vehicle's orientation can be accurately displayed on the image display device 60 .

[0080] Figure 9 1 is a diagram showing an example of a display of the image display device 60. As described above, the image display device 60 is, for example, a HUD. Figure 9 , a display area D on the front windshield of the vehicle is shown as the display area of the image display device 60 .

[0081] Information based on the vehicle's position, for example, includes an arrow C extending from the vehicle itself in the direction of travel. To display the arrow C, which extends from the vehicle itself in the direction of travel, in the display area D, it is necessary to estimate the vehicle's position. If the estimated vehicle position deviates from the actual position, the arrow C may appear to be off the road (for example, the vehicle may be heading toward a sidewalk or a building). The image control device 10 of this embodiment improves the accuracy of estimating the vehicle's position, thereby displaying the arrow C in the direction of travel.

[0082] As described above, the image control device 10 of this embodiment includes: a first obtaining unit 11 for obtaining the position of a vehicle measured and located by a satellite positioning system; a second obtaining unit 12 for obtaining an estimated position of the vehicle estimated based on a dead reckoning algorithm; a heading deviation estimating unit 13 for estimating a deviation in the vehicle's heading based on the position of the vehicle measured and located by the satellite positioning system and the estimated position of the vehicle estimated based on a dead reckoning algorithm; a heading calculating unit 14 for calculating an estimated heading of the vehicle based on the deviation in the estimated vehicle heading; and an output unit 15 for outputting the estimated heading of the vehicle to an image display device 60, which is a device for displaying information based on the vehicle's heading.

[0083] Satellite positioning systems can measure not only the vehicle's position but also its orientation based on changes in its position over time. However, positioning measurements performed by satellite positioning systems are performed at a frequency of only 1Hz (approximately once per second). Furthermore, there is a communication delay in obtaining the measured vehicle's position. Therefore, the vehicle's orientation constantly changes during movement, yet information based on the vehicle's orientation is displayed on the image display device based on this significantly delayed vehicle orientation.

[0084] Therefore, in this embodiment, the deviation in the vehicle's orientation is estimated based on the vehicle's position measured by a satellite positioning system and its estimated position estimated using dead reckoning. While the vehicle's position measured by a satellite positioning system may contain some error, it is close to the vehicle's actual position. On the other hand, if the vehicle's orientation used in the dead reckoning algorithm deviates from the estimated position, the deviation is accurately reflected in the estimated position to a certain extent. In other words, the deviation between the vehicle's position measured by a satellite positioning system and its estimated position estimated using dead reckoning is correlated with the deviation in the vehicle's orientation. Therefore, the deviation in the vehicle's orientation can be estimated based on the deviation between the vehicle's position measured by a satellite positioning system and its estimated position estimated using dead reckoning. This improves the accuracy of the estimated vehicle's orientation.

[0085] Furthermore, the heading deviation estimating unit 13 can estimate the heading deviation of the vehicle based on the first position of the vehicle, the second position of the vehicle, and the estimated position of the vehicle. The first position of the vehicle is a position measured by a satellite positioning system. The second position of the vehicle is a position measured by a satellite positioning system when the vehicle moves from the first position. The estimated position of the vehicle is the estimated position of the vehicle when measured at the second position, estimated using dead reckoning. Dead reckoning is a method that uses the first position, the heading of the vehicle at the first position, detection results from a gyro sensor 40 included in the vehicle, and vehicle speed information. Specifically, the heading deviation estimating unit 13 estimates the heading deviation of the vehicle as the angle formed by a line connecting the first position and the second position and a line connecting the first position and the estimated position.

[0086] The first and second positions are close to the vehicle's actual position. The estimated position is a position estimated based on dead reckoning, a method that uses, for example, gyroscopic sensor detection results based on the vehicle's orientation at the first position. As the vehicle moves from the first position to the second position, the amount by which the vehicle's trajectory based on dead reckoning deviates from the vehicle's trajectory from the first position to the second position, as measured using a satellite positioning system, is the deviation in the vehicle's orientation at the first position. Thus, the deviation between the vehicle's second position, as measured using a satellite positioning system, and the estimated position estimated based on dead reckoning corresponds to the deviation in the vehicle's orientation at the first position. Therefore, the deviation in the vehicle's orientation can be estimated based on the deviation between the second position and the estimated position. Specifically, the deviation in the vehicle's orientation at the first position can be considered the angle formed by the straight line connecting the first and second positions and the straight line connecting the first and estimated positions. Therefore, by calculating this angle, the deviation in the vehicle's orientation can be easily estimated.

[0087] In addition, the heading deviation estimation unit 13 can estimate the deviation of the vehicle's heading in each of a plurality of consecutive intervals based on the first position, the second position, and the estimated position in each of a plurality of consecutive intervals, and the heading calculation unit 14 can calculate the estimated heading of the vehicle based on the deviation of the vehicle's heading in two or more intervals among a plurality of consecutive intervals.

[0088] For example, by calculating the average or median of the deviations in the vehicle's orientation for two or more sections among the deviations in the vehicle's orientation in each of a plurality of consecutive sections, the accuracy of estimating the vehicle's orientation can be further improved.

[0089] In addition, the orientation calculation unit 14 can calculate the estimated orientation of the vehicle based on the average value of the deviation of the vehicle's orientation in each of multiple consecutive intervals excluding the following intervals, where the excluded intervals are intervals in which the vehicle's orientation changes by more than the first threshold value relative to the adjacent previous interval in multiple consecutive intervals, and the vehicle's orientation is the orientation calculated based on the detection result of the gyro sensor 40.

[0090] In sections where the vehicle's heading varies by more than a first threshold relative to the adjacent preceding section, there is a high probability that a sharp curve or a right or left turn exists, and the accuracy of the satellite positioning system's positioning measurement or the accuracy of the dead reckoning algorithm is likely insufficient. Therefore, by averaging the deviations in the vehicle's heading for each of multiple consecutive sections, excluding such sections, the accuracy of the estimated vehicle's heading can be further improved.

[0091] In addition, the direction calculation unit 14 can calculate the estimated direction of the vehicle based on the average value of the deviation of the vehicle's direction in each of multiple consecutive intervals excluding the following intervals, where the excluded intervals are intervals in which the deviation of the vehicle's direction is greater than the second threshold value among multiple consecutive intervals.

[0092] In intervals where the deviation of the estimated vehicle's heading exceeds the second threshold, the satellite positioning system's operation is unstable, and the second position of the vehicle measured by the satellite positioning system is likely to deviate significantly from the actual position. Therefore, by averaging the deviations of the vehicle's heading in each of multiple consecutive intervals, excluding such intervals, the accuracy of the estimated vehicle's heading can be further improved.

[0093] Furthermore, the direction calculation unit 14 may calculate the estimated direction of the vehicle based on the median value of the deviation of the vehicle's direction in each of a plurality of consecutive sections.

[0094] Through the above, it is possible to suppress the influence of the deviation of the vehicle's orientation (i.e., the deviation value) in the interval where the accuracy of the positioning measurement of the satellite positioning system or the accuracy of the dead reckoning method is insufficient among the deviations of the vehicle's orientation in each of multiple consecutive intervals, thereby further improving the accuracy of estimating the vehicle's orientation.

[0095] Furthermore, the direction calculation unit 14 may calculate the estimated direction of the vehicle based on a weighted average value of deviations in the direction of the vehicle in each of a plurality of consecutive sections.

[0096] Through the above, among the deviations of the vehicle's orientation in each of multiple consecutive intervals, a small weight can be set for the deviation of the vehicle's orientation in the interval where the accuracy of the positioning measurement of the satellite positioning system or the accuracy of the dead reckoning method is insufficient, and a weighted average value can be calculated, thereby suppressing the influence of the deviation of the vehicle's orientation in the interval, and thus the accuracy of estimating the vehicle's orientation can be further improved.

[0097] Furthermore, the output unit 15 may output the future estimated vehicle position, which is predicted based on the past variation in the estimated vehicle position, to the image display device 60 .

[0098] When displaying information based on the vehicle's position on the image display device 60, a rendering delay of approximately 33.3ms occurs. Therefore, when the vehicle's estimated position is output as is to the image display device 60, the information displayed on the image display device 60 is based on the vehicle's estimated position from approximately 33.3ms ago, as the vehicle's position changes over time. Therefore, by predicting the vehicle's estimated position in the future (approximately 33.3ms from now) based on the past change in the vehicle's estimated position calculated to date (for example, the change from approximately 16.6ms ago to the present), and outputting it to the image display device 60, the effects of rendering delay can be suppressed, allowing accurate display of information based on the vehicle's position on the image display device 60.

[0099] (Other embodiments)

[0100] As described above, the embodiments are described as examples of the technology involved in the present disclosure. However, the technology involved in the present disclosure is not limited to this, and can also be applied to embodiments that are appropriately changed, replaced, added, omitted, etc. For example, the following modified examples are also included in one embodiment of the present disclosure.

[0101] For example, in the above embodiment, the image control device 10 is described as being provided separately from the information processing device 20 and the image display device 60, but the present invention is not limited thereto. For example, the image control device 10 may be provided integrally with the information processing device 20, integrally with the image display device 60, or the image control device 10, information processing device 20, and image display device 60 may be provided integrally.

[0102] For example, in the above-mentioned embodiment, the vehicle is described as an automobile, but the vehicle is not limited to an automobile and may be a two-wheeled vehicle, a construction machine, an agricultural machine, or the like.

[0103] Furthermore, the present disclosure can be implemented not only as the image control device 10 but also as an image control method including steps (processing) performed by the components constituting the image control device 10 .

[0104] Specifically, if Figure 4 As shown, in the image control method, the position of the vehicle measured by the satellite positioning system is obtained (step S11), the estimated position of the vehicle estimated based on the dead reckoning algorithm is obtained (step S12), the deviation of the vehicle's orientation is estimated based on the position of the vehicle measured by the satellite positioning system and the estimated position of the vehicle estimated based on the dead reckoning algorithm (step S13), the estimated orientation of the vehicle is calculated based on the deviation of the estimated orientation of the vehicle (step S14), and the estimated orientation of the vehicle is output to the image display device 60, which is a device that displays information based on the orientation of the vehicle (step S15).

[0105] For example, the steps in the image control method can be executed by a computer (computer system). Furthermore, the present disclosure can be implemented as a program for causing a computer to execute the steps included in the image control method. Furthermore, the present disclosure can be implemented as a non-transitory computer-readable recording medium such as a CD-ROM that stores the program.

[0106] For example, when the present disclosure is implemented by a program (software), each step is performed by executing the program using hardware resources such as a computer CPU, memory, and input / output circuits. In other words, each step is performed by the CPU obtaining data from the memory or input / output circuits and performing calculations, or outputting the calculation results to the memory or input / output circuits.

[0107] Furthermore, each component included in the image control device 10 of the above-described embodiment may be implemented as a dedicated or general-purpose circuit.

[0108] Furthermore, each component included in the image control device 10 of the above embodiment may be implemented by an integrated circuit (IC), ie, LSI (Large Scale Integration).

[0109] Furthermore, integration of circuits is not limited to LSIs and can be realized by dedicated circuits or general-purpose processors. A programmable FPGA (Field Programmable Gate Array) or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI can be used.

[0110] Furthermore, if integrated circuit technology that can replace LSI emerges due to advancements in semiconductor technology or other derived technologies, it is natural to use this technology to integrate the components included in the image control device 10 into an integrated circuit.

[0111] In addition, various forms obtained by implementing various modifications conceived by those skilled in the art to the embodiments, and forms achieved by arbitrarily combining the constituent elements and functions in each embodiment without departing from the spirit of the present application are all included in the present disclosure.

[0112] The present disclosure can be applied to, for example, a device that displays information based on the position of a vehicle.

[0113] Explanation of symbols

[0114] 10 Image control device

[0115] 11 Part 1

[0116] 12 Part 2

[0117] 13. Azimuth Deviation Estimation Unit

[0118] 14. Direction Calculation Unit

[0119] 15 Output

[0120] 20 Information processing device

[0121] 30 ECU

[0122] 40 gyroscope sensors

[0123] 50 accelerometers

[0124] 60 Image display device

Claims

1. An image control device comprising: A first obtaining unit obtains a position of the vehicle measured by a satellite positioning system; a second obtaining unit for obtaining an estimated position of the vehicle estimated based on a dead reckoning algorithm; a heading deviation estimating unit configured to estimate a deviation in the heading of the vehicle based on the position of the vehicle measured by a satellite positioning system and the estimated position of the vehicle estimated based on a dead reckoning algorithm; a direction calculating unit for calculating an estimated direction of the vehicle based on a deviation of the estimated direction of the vehicle; as well as an output unit that outputs the estimated position of the vehicle to an image display device that displays information based on the position of the vehicle; The direction deviation estimating unit estimates the deviation of the vehicle's direction based on the first position of the vehicle, the second position of the vehicle, and the estimated position of the vehicle. The first position of the vehicle is a position measured by a satellite positioning system. The second position of the vehicle is a position measured by a satellite positioning system when the vehicle moves from the first position. The estimated position of the vehicle is an estimated position of the vehicle when the second position is measured and estimated based on the dead reckoning method, wherein the dead reckoning method is a method using the first position, the orientation of the vehicle at the first position, a detection result of a gyro sensor included in the vehicle, and speed information of the vehicle. The heading deviation estimating unit estimates a deviation of the vehicle's heading in each of the plurality of consecutive sections based on the first position, the second position, and the estimated position in each of the plurality of consecutive sections. The direction calculation unit calculates an estimated direction of the vehicle based on a deviation in the direction of the vehicle in two or more sections among the plurality of continuous sections.

2. The image control device according to claim 1, The heading deviation estimating unit estimates an angle formed by a straight line connecting the first position and the second position and a straight line connecting the first position and the estimated position as a heading deviation of the vehicle.

3. The image control device according to claim 1, The orientation calculation unit calculates the estimated orientation of the vehicle based on an average value of the deviation of the orientation of the vehicle in each of the multiple consecutive intervals excluding the following intervals, wherein the excluded intervals are intervals in which the orientation of the vehicle changes by more than a first threshold value relative to an adjacent previous interval, and the orientation of the vehicle is the orientation calculated based on the detection result of the gyro sensor.

4. The image control device according to claim 1, The orientation calculation unit calculates the estimated orientation of the vehicle based on the average value of the deviation of the orientation of the vehicle in each of the multiple consecutive intervals excluding the following intervals, where the excluded intervals are intervals in the multiple consecutive intervals in which the deviation of the orientation of the vehicle is greater than a second threshold value.

5. The image control device according to claim 1, The direction calculation unit calculates the estimated direction of the vehicle based on a median value of deviations of the vehicle's direction in each of the plurality of consecutive sections.

6. The image control device according to claim 1, The direction calculation unit calculates the estimated direction of the vehicle based on a weighted average value of deviations in the direction of the vehicle in each of the plurality of consecutive sections.

7. The image control device according to any one of claims 1 to 6, The output unit outputs the estimated future position of the vehicle, which is predicted based on the past variation of the estimated position of the vehicle, to the image display device.

8. An image control method, Obtaining the position of the vehicle measured by a satellite positioning system, obtaining an estimated position of the vehicle estimated based on dead reckoning, estimating a deviation in the orientation of the vehicle based on the position of the vehicle measured by a satellite positioning system and the estimated position of the vehicle estimated based on dead reckoning. Calculating an estimated position of the vehicle based on the deviation of the estimated position of the vehicle, Outputting the estimated position of the vehicle to an image display device, which is a device that displays information based on the position of the vehicle, in, estimating a deviation in the orientation of the vehicle based on the first position of the vehicle, the second position of the vehicle, and the estimated position of the vehicle; The first position of the vehicle is a position measured by a satellite positioning system. The second position of the vehicle is a position measured by a satellite positioning system when the vehicle moves from the first position. The estimated position of the vehicle is an estimated position of the vehicle when the second position is measured and estimated based on the dead reckoning method, wherein the dead reckoning method is a method using the first position, the orientation of the vehicle at the first position, a detection result of a gyro sensor included in the vehicle, and speed information of the vehicle. estimating a deviation in the orientation of the vehicle in each of a plurality of consecutive sections based on the first position, the second position, and the estimated position in each of a plurality of consecutive sections, The estimated direction of the vehicle is calculated based on the deviation of the direction of the vehicle in two or more sections among the plurality of continuous sections. 9 . A computer-readable recording medium having a program recorded thereon, the program causing a computer to execute the image control method according to claim 8 .

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