Vehicle control system and method for generating a speed limit signal

Abstract

Aspects of the invention relate to a control system for generating a speed limit signal for controlling a vehicle and a method for a control system. The control system is configured to receive image data indicative of an environment of the vehicle from one or more imaging devices associated with the vehicle. The control system is configured to determine a speed limit indicated by a traffic sign and a position of the traffic sign relative to a road feature in the environment from the image data. A relevance of the speed limit to the vehicle is determined from the determined position of the traffic sign and a determined position of the vehicle. A sign speed limit signal indicative of the speed limit is selectively generated from the determined relevance and output to at least one vehicle control system. Thus, traffic signs associated with a bypass SR and thus not relevant to the vehicle can be effectively filtered.

Description

Technical Field

[0001] This disclosure relates to the generation of speed limit signals. Aspects of the invention relate to control systems for generating speed limit signals, vehicles, and computer-implemented methods for generating speed limit signals. Background Technology

[0002] Traffic sign recognition (TSR) systems in vehicles are designed to identify upcoming traffic signs, enabling the vehicle systems to be updated or controlled accordingly. These traffic signs include speed limit signs. Recognition of speed limit signs can be used, for example, to update or override speed limits extracted from map data when a temporary speed limit exists. Recognition of speed limit signs can also be used, for example, to provide speed limit information when no speed limit is available in map data because the vehicle is located on a road segment not present in the map data.

[0003] If possible, the TSR system operates by recognizing all traffic signs in the image lens or video data that indicate the environment ahead of the vehicle. However, some of the recognized traffic signs may not be applicable to the road the vehicle is traveling on. Incorrect recognition of an approaching speed limit sign can cause inconvenience to the driver.

[0004] The purpose of this invention is to address one or more disadvantages associated with the prior art. Summary of the Invention

[0005] The present invention provides, in various aspects and embodiments, a control system, a vehicle, and a computer-implemented method, as described below.

[0006] According to one aspect of the invention, a control system for generating speed limit signals for controlling a vehicle is provided, the control system comprising one or more controllers. The control system is configured to receive image data indicating the vehicle's environment from one or more imaging devices associated with the vehicle; determine speed limits indicated by traffic signs and the positions of the traffic signs based on the image data; determine the correlation between the speed limits and the vehicle based on the determined positions of the traffic signs and the determined position of the vehicle; and selectively generate sign speed limit signals indicating the speed limits based on the determined correlation. The control system can output the selectively generated signals to at least one vehicle control system.

[0007] According to another aspect, a control system for generating speed limit signals for controlling a vehicle is provided, the control system comprising one or more controllers. The control system is configured to receive image data indicating the vehicle's environment from one or more imaging devices associated with the vehicle; determine, based on the image data, a speed limit indicated by a traffic sign and the position of the traffic sign relative to the edge of the road on which the vehicle is located; determine the relevance of the speed limit to the vehicle based on the determined position of the traffic sign relative to the road edge and the determined position of the vehicle; selectively generate a sign speed limit signal indicating the speed limit based on the determined relevance; and output the selectively generated signal to at least one vehicle control system. Advantageously, the proximity of the traffic sign to the road edge can be used to determine whether the traffic sign is applicable to the road on which the vehicle is located. Therefore, irrelevant speed limit signs can be filtered out.

[0008] According to another aspect, a control system for generating speed limit signals for controlling a vehicle is provided, the control system comprising one or more controllers. The control system is configured to receive image data indicating the vehicle's environment from one or more imaging devices associated with the vehicle; determine, based on the image data, a speed limit indicated by a traffic sign and the position of the traffic sign relative to an entrance to a bypass; determine the correlation between the speed limit and the vehicle based on the determined position of the traffic sign relative to the entrance and the determined position of the vehicle; selectively generate a sign speed limit signal indicating the speed limit based on the determined correlation; and output the selectively generated signal to at least one vehicle control system. Advantageously, the proximity of the traffic sign to the entrance to the bypass can be used to determine whether the traffic sign is applicable to the road on which the vehicle is located. Therefore, irrelevant speed limit signs can be filtered out.

[0009] According to another aspect, a control system for generating speed limit signals for controlling a vehicle is provided, the control system comprising one or more controllers. The control system is configured to receive image data indicating the vehicle's environment from one or more imaging devices associated with the vehicle; determine, based on the image data, a speed limit indicated by a traffic sign and the position of the traffic sign relative to another traffic sign indicating the speed limit; determine the correlation between the speed limit and the vehicle based on the determined position of the traffic sign relative to the other traffic sign and the determined position of the vehicle; selectively generate a sign speed limit signal indicating the speed limit based on the determined correlation; and output the selectively generated signal to at least one vehicle control system. Advantageously, the pairing of traffic signs with another traffic sign and the position of said pair can be used to determine whether the traffic sign is applicable to the road where the vehicle is located. Therefore, irrelevant speed limit signs can be filtered out.

[0010] According to another aspect, a control system for generating speed limit signals for controlling a vehicle is provided, the control system comprising one or more controllers. The control system is configured to receive image data indicating the vehicle's environment from one or more imaging devices associated with the vehicle; determine, based on the image data, a speed limit indicated by traffic signs and the position of the traffic signs relative to road features in the environment; determine the correlation between the speed limit and the vehicle based on the determined position of the traffic signs and the determined position of the vehicle; selectively generate a sign speed limit signal indicating the speed limit based on the determined correlation; and output the selectively generated signal to at least one vehicle control system. Advantageously, the identified road features can be used to determine whether the traffic signs are applicable to the road where the vehicle is located. Therefore, irrelevant speed limit signs can be filtered out.

[0011] Selectively generated signals can be output to the user to notify them of relevant speed limits. Selectively generated signals can also be output to adjust the vehicle's cruise control system. Additionally or alternatively, selectively generated signals can be output to a warning system to provide alerts to the driver, such as alerting them that they are exceeding relevant speed limits.

[0012] Determining relevance can include classifying speed limits as vehicle-related or unrelated. Based on the vehicle's predicted path, the determined relevance can indicate the likelihood that the traffic sign is associated with the road segment where the vehicle is currently located or the road segment where the vehicle will be located. A speed limit can be classified as unrelated based on the likelihood that the traffic sign applies to a bypass where the vehicle is not located. A sign speed limit signal can be selectively output based on whether the speed limit is determined to be relevant. Alternatively, a sign speed limit signal can be selectively output based on whether the speed limit is determined to be relevant to vehicle characteristics. For example, it can be determined that the traffic sign applies to the road segment where the vehicle is currently located, but is only relevant to road segments with specific characteristics, such as vehicles exceeding a certain size.

[0013] Optionally, the control system is configured to receive digital map data, which includes indications of map speed limits associated with the road segment where the vehicle is located. If a speed limit indicated by a traffic sign is determined to be irrelevant, the control system can be configured to generate a map speed limit signal indicating the map speed limit, and output the map speed limit signal to at least one vehicle control system. If a speed limit indicated by a traffic sign is determined to be relevant, the control system can be configured to preferentially output the sign speed limit signal. Advantageously, only speed limits indicated by relevant road signs can override speed limits indicated by map data.

[0014] Optionally, determining the location of a traffic sign includes determining the distance from the traffic sign to a road feature. The relevance of a speed limit can be determined based on whether the distance meets predetermined criteria, such as a minimum or maximum distance.

[0015] According to the implementation, road features include the edge of the road where the vehicle is located. The road where the vehicle is located and / or the road where the vehicle is predicted to be located given its trajectory can subsequently be referred to as the main road. Any road other than the main road can subsequently be referred to as a bypass. A bypass can be any road on which the vehicle is not located. For example, a bypass can be a road branching off from or intersecting with the main road, or a road that does not meet the main road. For example, a bypass can include a road that is substantially parallel to the main road. The control system can be configured to determine the distance from the traffic sign to the edge of the main road. Optionally, this distance is a lateral distance. The lateral distance can be defined as the distance intercepted substantially perpendicular to the road edge. Advantageously, for a given geographic area, such as for a given country, the lateral distance of the traffic sign from the road edge is largely standardized.

[0016] The control system can be configured to determine that a speed limit is irrelevant to the vehicle if the determined distance to the road edge is greater than a predetermined threshold. The predetermined threshold can be set based on standardized distances to the geographic area where the vehicle is located. Advantageously, filtering traffic signs whose lateral distance exceeds this threshold effectively filters out traffic signs that are too far from the road edge and therefore unlikely to be applicable to the road where the vehicle is located.

[0017] According to the implementation, at least one road feature includes an entrance end to the bypass. The entrance end can be defined as the point where the bypass branches off from or deviates from the main road. The entrance end can be any intersection, such as a fork in the road, a roundabout, or a junction.

[0018] The control system can be configured to determine the location of the traffic sign by determining the end distance from the traffic sign to the entrance end of the bypass. Advantageously, proximity to the entrance end indicates the possibility that the traffic sign applies to the bypass and is therefore irrelevant to vehicles.

[0019] Optionally, the control system is configured to: receive digital map data indicating a map speed limit associated with the bypass; and determine that the speed limit is irrelevant if the speed limit and the map speed limit associated with the bypass match and the end distance is less than a predetermined end distance threshold. Advantageously, if the speed limit matches a speed limit that would be expected to apply to the bypass based on the digital map data, the traffic sign can simply be ignored as irrelevant. In this way, a traffic sign applicable to the main road that happens to appear near the entrance end of the bypass will not be mistakenly considered irrelevant.

[0020] According to the implementation, road features include additional traffic signs indicating speed limits. The control system can be configured to determine whether a traffic sign and the additional traffic signs cross a bypass based on the position of the traffic sign relative to the additional traffic signs. Crossing a bypass means that the traffic sign and the additional traffic signs are located on either side of a bypass at a given location. The control system can be configured to determine that the speed limit is irrelevant if the traffic sign and the additional traffic signs cross a bypass. Advantageously, signs are present on each side of the road indicating their association with the road extending between them. Therefore, if a sign and the additional traffic signs cross a bypass, the sign can be effectively filtered as irrelevant to the main road.

[0021] Optionally, if both the traffic sign and another traffic sign are offset to the first side of the vehicle's path, then the traffic sign and the other traffic sign can be identified as crossing a bypass. Optionally, if the distance between the traffic sign and the other traffic sign is greater than a predetermined minimum distance, then the traffic sign and the other traffic sign are identified only as crossing a bypass. Optionally, if the distance between the traffic sign and the other traffic sign is less than a predetermined maximum distance, then the traffic sign and the other traffic sign can be identified only as crossing a bypass.

[0022] Optionally, the controller or each controller includes: an electrical input for receiving an electrical signal indicating image data; an electrical output for outputting an electrical signal indicating a speed limit; and one or more electronic processors for operatively executing computer-readable instructions to determine the relevance of the speed limit.

[0023] According to another aspect of the present invention, a vehicle including the control system as described above is provided.

[0024] According to another aspect, a computer-implemented method for generating a speed limit signal for controlling a vehicle is provided, the method comprising: receiving image data indicating the environment of the vehicle from one or more imaging devices associated with the vehicle; determining, based on the image data, a speed limit indicated by traffic signs and the position of the traffic signs relative to road features in the environment; determining the correlation between the speed limit and the vehicle based on the determined position of the traffic signs and the determined position of the vehicle; selectively generating a sign speed limit signal indicating the speed limit based on the determined correlation; and outputting the selectively generated signal to at least one vehicle control system.

[0025] Optionally, the method includes: receiving digital map data, the digital map data including indications of map speed limits associated with the road segment where the vehicle is located; and if a speed limit indicated by a traffic sign is determined to be irrelevant, generating a map speed limit signal indicating the map speed limit and outputting the map speed limit signal to at least one vehicle control system. The method may include prioritizing the output of a sign speed limit signal based on whether the traffic sign is determined to be relevant.

[0026] Optionally, determining the location of a traffic sign includes determining the distance from the traffic sign to a road feature.

[0027] Road features may include the edge of the road on which the vehicle is located, and identifying the location of traffic signs includes determining the distance from the traffic sign to the edge of the road; and the method may include determining that the speed limit is irrelevant to the vehicle if the determined distance to the edge of the road is greater than a predetermined threshold.

[0028] Optionally, at least one road feature may include an entrance end to the bypass, and wherein determining the location of the traffic sign may include determining the end distance from the traffic sign to the entrance end of the bypass.

[0029] Optionally, the method may include: receiving digital map data indicating a map speed limit associated with a bypass; and determining that the speed limit is irrelevant if the speed limit and the map speed limit associated with the bypass match and the end distance is less than a predetermined end distance threshold.

[0030] Optionally, the road features may include additional traffic signs indicating speed limits, and the method may include determining whether the traffic sign and the additional traffic sign cross a bypass based on the position of the traffic sign relative to the additional traffic sign.

[0031] Optionally, the controller or each controller can be configured to determine speed limits based on traffic signs and other traffic signs crossing the bypass.

[0032] According to another aspect, a computer-readable medium is provided that includes computer software, which, when executed, causes the above-described methods to be performed.

[0033] Within the scope of this application, it is expressly intended that all aspects, embodiments, examples, and alternatives set forth in the preceding paragraphs, claims, and / or the following description and drawings, and in particular their various features, may be adopted independently or in any combination. That is, all embodiments and / or features of any embodiment may be combined in any manner and / or combination, unless such features are incompatible. The applicant reserves the right to amend any originally filed claim or correspondingly file any new claim, including the right to modify any originally filed claim to be subordinate to any other claim and / or incorporated into any other claim, even though it was not initially claimed in this manner. Attached Figure Description

[0034] One or more embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:

[0035] Figure 1 A first schematic diagram of a control system according to an embodiment is shown;

[0036] Figure 2 A vehicle according to an embodiment is shown;

[0037] Figure 3 The image shows vehicles traveling on the main road;

[0038] Figure 4A This illustrates a first type of bypass adjacent to the main road;

[0039] Figure 4B This illustrates a second type of bypass that is not adjacent to the main road;

[0040] Figure 5 A method according to an embodiment of the present invention is shown;

[0041] Figure 6 It shows the distance from the traffic sign to the edge of the main road;

[0042] Figure 7 Traffic signs indicating the approach to the bypass entrance are shown;

[0043] Figure 8 Two traffic signs are shown crossing the bypass;

[0044] Figure 9 A method for determining correlation according to an embodiment of the present invention is shown; and

[0045] Figure 10 A second schematic diagram of a control system according to an embodiment is shown. Detailed Implementation

[0046] A control system 110 according to an embodiment of the present invention will now be described with reference to the accompanying drawings. The control system 110 in this embodiment is a traffic sign recognition (TSR) system. As will be explained, the traffic sign recognition system is used to generate speed limit signals to control the vehicle based on the relevance of the recognized traffic signs. Figure 2 As shown, the control system 110 is installed in the vehicle 200. The vehicle 200 in this embodiment is a wheeled vehicle such as an automobile, but it should be understood that the control system 110 can be used for other types of land vehicles and vessels operating on waterways subject to speed limits.

[0047] Reference Figure 1 The control system 110 is communicatively coupled to a sensor unit 120 associated with the vehicle 200. In this embodiment, the sensor unit 120 includes an optical imaging device having a field of view extending forward toward the vehicle 200. The sensor unit 120 may include one or more optical imaging devices, such as stereoscopic imaging devices. Alternatively or additionally, the sensor unit 120 may include other types of sensors, such as radar systems or LIDAR systems, for capturing representations of the area in front of the vehicle 200. In this embodiment, the sensor unit 120 is located behind a rearview mirror (not shown) positioned at the top of the windshield of the vehicle 200. Other mounting locations are possible. For example, the sensor unit 120 may be located behind or within the front grille of the vehicle 200. The control system 110 is configured to receive image data 125 from the sensor unit 120 indicating at least the area in front of the vehicle 200.

[0048] The control system includes a processing device 111 and a memory device 114. The processing device may be one or more electronic processing devices 111. The memory device 114 may be one or more memory devices 114. The memory device 114 is electrically coupled to the processing device 111. The memory device 114 is configured to store instructions, and the processing device 111 is configured to access the memory device 114 and execute the instructions on the memory device 114.

[0049] like Figure 3As shown, vehicle 200 is located on a road hereinafter referred to as the main road PR. Control system 110 is configured to receive digital map data 140 indicating the main road PR. The digital map data 140 may be stored in a memory 114 accessible to control system 110, or may be transmitted to control system 110, for example, from a remote map server, as vehicle 200 travels along the main road PR. The digital map data 140 includes indications of map speed limits associated with the segment of the main road PR where the vehicle is located. For example, digital map data 140 may indicate that vehicle 200 is located on a segment of the main road PR with a speed limit of 40 km / h. The segment of the main road may be defined between a first node and a second node of the map data. The map speed limits may be used by one or more additional vehicle control systems 130. Vehicle control system 130 may include a cruise control system 130 arranged to operatively adjust the speed of vehicle 200. Alternatively or additionally, the vehicle control system 130 may include a speed limit display system or a driver warning system for alerting the driver to speed limits or for warning the driver when the vehicle exceeds the speed limit.

[0050] In some instances, the digital map data 140 may be inaccurate. For example, the digital map data 140 may be outdated, or there may be temporary speed limits at certain locations, for example, due to road construction. Therefore, the control system 110 is configured to identify traffic signs 300 in the received image data 125 and determine the speed limit indicated by the traffic signs 300. The control system 110 can then output a speed limit signal 135 indicating the speed limit (i.e., the speed limit for a road segment conveyed or indicated by the road signs) to one or more other vehicle control systems 130. Figure 3 In the illustrated embodiment, the control system 110 can output a marked speed limit signal 135 indicating a determined speed limit of 30 km / h. Therefore, in cases where the marked speed limit does not match the map speed limit, the marked speed limit signal can override or replace the map speed limit. Then, another control system 130 can use a newer speed limit, for example, 30 km / h, instead of the 40 km / h indicated by the digital map data.

[0051] In this way, the speed limit indicated by the traffic sign 300 detected by the sensor unit 120 can cover the map speed limit. Then, the vehicle control system 130, such as the cruise control system 130, can take into account recently changed speed limits and temporary speed limits that are not yet reflected in the digital map data 140. Furthermore, the speed limit indicated by the traffic sign 300 can provide speed limit information when map speed limit information is unavailable (e.g., when the vehicle is on a road segment not present in the digital map data 140).

[0052] However, not every traffic sign detected by sensor unit 120 is associated with vehicle 200. If traffic sign 300 is associated with main road PR (i.e., the road where the vehicle is located), then traffic sign 300 can be defined as associated with vehicle 200.

[0053] Figure 4A and Figure 4B Two examples of traffic signs 300 not associated with vehicle 200 are shown. Traffic sign 300 can be associated with another road adjacent to the main road PR, making the road sign associated with the other road visible to sensor unit 120. For example, traffic sign 300 can be associated with a bypass SR. Any road other than the main road can hereafter be referred to as a bypass SR. A bypass SR can be any road on which the vehicle does not travel. Figure 4A In this context, a bypass SR is a road branching off from the main road PR. A bypass SR can also be a road intersecting the main road, or a road turning from the main road PR at an intersection, such as a roundabout or keyway. In some examples, a bypass SR can be a road that does not intersect with the main road at all. Figure 4B In this context, the bypass SR is a separate road that is basically parallel to the main road.

[0054] exist Figure 4A and Figure 4B In each example, traffic sign 300 can be detected by the control system 110 of vehicle 200 traveling on the main road PR. However, each traffic sign 300 shown is associated with the bypass SR instead of the main road PR. Therefore, if the control system 110 outputs a sign speed limit signal indicating a speed limit of 30 km / h, this may incorrectly override the correct speed limit of 40 km / h for the main road PR indicated by digital map data, causing the vehicle system to unnecessarily adjust the control of vehicle 200.

[0055] Therefore, the control system 110 is designed to determine whether the traffic sign 300 is associated with the vehicle 200 when the sign is detected by the sensor unit 120. In terms of being associated with the vehicle 200, this means whether the traffic sign 300 is associated with the main road PR. If it is determined that the traffic sign 300 is not associated with the vehicle 200, for example, because it is associated with the bypass SR, the control system 110 can suppress or avoid the generation of the sign speed limit signal 135.

[0056] Figure 5 An operation method 500 of a control system 110 according to an embodiment of the present invention is shown.

[0057] Method 500 includes a block 510 for receiving image data indicating the environment of vehicle 200. As described, control system 110 may be configured to receive image data 125 from sensor unit 120. Image data 125 may indicate an area in front of vehicle 200 and may include representations of one or more traffic signs 300 present in the image data.

[0058] Method 500 includes a block 520 for identifying at least one traffic sign 300 in image data 125. As those skilled in the art will understand, the traffic sign 300 can be identified by processing the image data 125 to search for predetermined shapes, colors, and / or textures in the image that match known traffic sign standards. Block 520 also includes determining a speed limit indicated by the traffic sign 300. The speed limit can be determined, for example, using any known image processing technique, such as using pictographic contours. For example, block 520 may include identifying a traffic sign 300 in image data 125 indicating a speed limit of 30 km / h.

[0059] Method 500 includes block 530 for determining the relevance of a sign speed limit to vehicle 200. Determining the relevance may include classifying the speed limit as either relevant to or unrelevant to vehicle 200. The determined relevance may indicate the likelihood that the traffic sign is associated with the main road PR. If it is determined that the traffic sign may apply to the bypass SR, the speed limit may be classified as unrelevant.

[0060] The speed limit sign can be determined to be relevant or irrelevant based on the position of the traffic sign 300 relative to road features in the environment. As will be explained, in different implementations, the road features can be one or more of the following: the edge of a main road, the entrance stub of a bypass, or other traffic signs. The position of the traffic sign relative to the road features can indicate the likelihood that the traffic sign is associated with the bypass SR.

[0061] Reference Figure 6 According to some embodiments, block 530 includes identifying a road edge 600 of the main road PR. The road edge 600 in image data 125 can be identified, for example, by recognizing contrast and / or color changes in image data 125 that may indicate the road edge 600. For example, a transition or boundary between a potentially relatively smooth surface (e.g., defined by asphalt, concrete, or other paving materials) and a potentially relatively rough adjacent surface (e.g., composed of one or more of the following: grass, mud, gravel, sand, and snow) can be identified. In other examples, the road edge 600 can be determined based on road markings or physical markings or boundaries such as curbs identified on the main road PR.

[0062] The control system can then be configured to determine a distance 610 between the road edge 600 and the traffic sign 300. This distance can be a lateral distance 610, i.e., a distance substantially perpendicular to the road edge 600. The distance 610 can be determined based on image data 125 by determining a lateral distance 630 between the vehicle 200 and the road edge 600, and a lateral distance 620 between the vehicle 200 and the traffic sign 300. Each determined distance 620 and distance 630 can be inferred using known image processing techniques based on the size and / or position of the traffic sign 300 in image data 125 and the road edge 600.

[0063] In block 530, if the determined lateral distance 610 between the road edge 600 and the traffic sign 300 meets a predetermined criterion, the control system 110 can determine that the speed limit is not associated with the vehicle. The predetermined criterion may be that the distance 610 is greater than or equal to a predetermined threshold. The predetermined threshold can be defined based on the geographical location of the vehicle 200, for example, based on the country where the vehicle 200 is located. Local regulations can define a standardized range for the distance between the traffic sign 300 and the road edge 600. If the distance 610 is greater than the upper limit of the standardized range, it can be determined that the traffic sign 300 is not associated with the main road PR because it is too far from the road edge 600.

[0064] According to some implementations, road features may include the entrance end to the bypass SR. (See reference...) Figure 7 The entrance end 700 can be the area where the bypass SR and the main road PR intersect. The entrance end 700 can be a fork in the road, a crossroads, a side-turn lane, or any other intersection. In some embodiments, block 530 may include identifying the entrance end 700 in image data 125. For example, the entrance end 700 in image data 125 can be identified by identifying gaps or forks in the road edge 600. Alternatively or additionally, the control system 110 can identify the position of the entrance end 700 relative to the vehicle 200 based on digital map data 140. The digital map data 140 may indicate the location of the node where the bypass SR segment forks from the main road PR segment where the vehicle 200 is located.

[0065] In block 530, control system 110 can determine the end distance 710 from traffic sign 300 to entrance end 700. The positions of one or more boundaries 705, 706 defining the edge of entrance end 700 can be determined based on image data 125 or digital map data 140. The end distance 710 can then be determined as the distance between traffic sign 300 and the nearest boundary 705, 706 to that traffic sign. In the illustrated embodiment, traffic sign 300 is positioned behind entrance end 300 along the main road PR relative to the direction of travel of vehicle 200, and the nearest boundary is boundary 705. However, if traffic sign 300 is positioned before entrance end 700, the nearest boundary for traffic sign 300 can be boundary 706. According to some embodiments, end distance 710 can be defined as the distance from traffic sign 300 to an alternative point on entrance end 700, such as the midpoint of entrance end 700.

[0066] Digital map data 140 can indicate the map speed limit associated with the bypass SR. In block 540, control system 110 can determine whether the map speed limit associated with the bypass matches the sign speed limit. If the map speed limit associated with the bypass matches the sign speed limit, this can indicate that traffic sign 300 is associated with the bypass SR and therefore not with vehicle 200.

[0067] To more accurately ensure that traffic sign 300 is associated with the bypass SR, control system 110 can be configured to determine whether the end distance 710 is less than a predetermined end distance threshold, i.e., whether traffic sign 300 is sufficiently close to the entrance end 700 for positioning. If the end distance 710 is less than the end distance threshold, and the map speed limit associated with the bypass matches the sign speed limit, then control system 110 can determine that traffic sign 300 is associated with the bypass SR and therefore not with vehicle 200.

[0068] Reference Figure 8 According to some implementations, the control system 110 can be configured to determine that the traffic sign 300 is not related to the vehicle 200 based on the position of the traffic sign 300 relative to another traffic sign 800. If both the first traffic sign 300 and the second traffic sign 800 are recognized by the control system 110, then in block 530, the control system 110 can determine whether the first traffic sign 300 and the second traffic sign 800 cross the bypass SR.

[0069] exist Figure 8In the diagram, the first traffic sign 300 and the second traffic sign 800 are shown crossing the bypass SR. "Crossing the bypass SR" means that the first traffic sign 300 and the second traffic sign 800 are located on opposite sides of the bypass SR and are generally aligned along an axis perpendicular to the bypass SR. The pair of traffic signs 300 and 800 shown can be referred to as gate signs. Such gate signs are often used to indicate changes in speed limits, and placing traffic signs on each side of the road allows drivers to easily infer which road the traffic sign relates to. By determining that the first traffic sign 300 and the second traffic sign 800 cross the bypass, it can be inferred that each of the first traffic sign 300 and the second traffic sign 800 is associated with the bypass SR and therefore not with vehicle 200.

[0070] If one or more crossing criteria are met, then the first traffic sign 300 and the second traffic sign 800 are determined to cross the bypass SR. The first crossing criterion may be that the first traffic sign 300 and the second traffic sign 800 indicate the same speed limit. The second crossing criterion may be that each of the first traffic sign 300 and the second traffic sign 800 is located on the same side of the vehicle 200. The third crossing criterion may be that the distance between the first traffic sign 300 and the second traffic sign 800 is less than a threshold, i.e., the traffic signs 300 and 800 are sufficiently close together.

[0071] The methods described above for determining the correlation between traffic sign 300 and vehicle 200 can be performed individually or in combination. Figure 9 Example operation of the control system 110 according to an embodiment during block 530 is shown. In the illustrated embodiment, the control system 110 sequentially performs each of the methods described above to determine the correlation between the traffic sign 300 and the vehicle 200.

[0072] In step 531, it is determined whether the sign speed limit matches the map speed limit associated with the bypass SR. If the sign speed limit matches the map speed limit, then in step 532, it is determined whether the end distance 710 to the entrance end 700 of the bypass SR is less than a threshold. If the end distance 710 is less than the end distance threshold, it is determined that the traffic sign 300 is associated with the bypass SR at the end entrance and therefore is not associated with the vehicle. If it is determined that the traffic sign 300 is not associated with the end entrance 700, then the control system 110 proceeds to step 533. In step 533, it is determined whether the distance 610 between the traffic sign 300 and the road edge 600 of the main road is greater than a threshold. If the distance 610 is greater than the threshold, it can be determined that the traffic sign 300 is not associated with the vehicle 200. If the traffic sign is sufficiently close to the road edge 600, then the control system 110 proceeds to step 534. In step 534, it is determined whether the traffic sign 300 and another traffic sign 800 cross the bypass SR. If it is determined that traffic sign 300 constitutes part of a pair crossing the bypass, then traffic sign 300 is determined to be unrelated to vehicle 200. If it is determined in any of steps 531 to 534 that traffic sign 300 is not associated with bypass SR or is not too far from the road edge 600, then traffic sign 300 is likely associated with main road PR, and traffic sign 300 is determined to be related to vehicle 200.

[0073] It should be understood that in some embodiments, steps 531 to 534 may be performed in an alternative order. Furthermore, in some embodiments, one or more of steps 531 to 534 may be omitted. For example, in one embodiment, in block 530, the control system may perform only step 533, and if the traffic sign 300 is sufficiently close to the road edge 600, the traffic sign 300 may be identified as relevant.

[0074] Method 500 includes block 540 for selectively generating a sign speed limit signal indicating the speed limit of traffic sign 300. The sign speed limit signal can be selectively generated based on a determination in block 530 that traffic sign 300 is associated with vehicle 200. If traffic sign 300 is not associated with the vehicle, then in block 540, control system 110 can determine not to generate a signal. Alternatively, control system 110 can generate a map speed limit signal indicating the map speed limit for main road PR as indicated in digital map data 140. Method 500 includes block 550 for outputting the generated signal to one or more additional vehicle control systems 130. The one or more vehicle control systems 130 may include a cruise control system, a display or warning system for informing the driver of the speed limit.

[0075] Therefore, by implementing method 500, the traffic sign recognition system can override speed limits derived from digital map data only if it is determined that the identified traffic sign is associated with a vehicle. Traffic signs associated with bypasses on which vehicle 200 does not travel can be effectively filtered, and erroneous adjustments to speed limits input to other vehicle systems 130, such as cruise control system 130, can be mitigated.

[0076] Reference Figure 10 A simplified example of a control system 110 suitable for implementing the methods described herein is shown. The control system 110 includes one or more controllers 1000 and is configured to generate a speed limit signal 135 for controlling a vehicle 200. The control system 110 is configured to receive image data 125 indicating the vehicle's environment from one or more imaging devices 120 associated with the vehicle. The control system 110 is configured to determine, based on the image data 125, a speed limit indicated by a traffic sign 300 and the position of the traffic sign relative to road features in the environment. The control system 110 is configured to determine the correlation between the speed limit and the vehicle based on the determined position of the traffic sign 300 and the determined position of the vehicle 200; selectively generate a sign speed limit signal 135 indicating the speed limit based on the determined correlation; and output the selectively generated signal 135 to at least one vehicle control system 130.

[0077] It should be understood that controller 1000 or each controller 1000 may include control units or computing devices having one or more electronic processors (e.g., microprocessors, microcontrollers, application-specific integrated circuits (ASICs), etc.), and may include a single control unit or computing device, or alternatively, different functions of controller 1000 or each controller 1000 may be embodied in or hosted in different control units or computing devices. As used herein, the terms “controller,” “control unit,” or “computing device” will be understood to include a single controller, control unit, or computing device, as well as multiple controllers, control units, or computing devices that operate together to provide the desired control functions. A set of instructions may be provided, which, when executed, cause controller 1000 to implement some or all of the control techniques described herein (including some or all of the functions required by the methods described herein). The set of instructions may be embedded in the one or more electronic processors of controller 1000; or alternatively, the set of instructions may be provided as software to be executed in controller 1000. The first controller or control unit may be implemented in software running on one or more processors. One or more additional controllers or control units can be implemented in software running on one or more processors (optionally the same processors as the first controller or control unit). Other arrangements are also useful.

[0078] exist Figure 10 In the example shown, controller 1000 or each controller 1000 includes at least one electronic processor 111, which has one or more electrical inputs 112 for receiving one or more input signals and one or more electrical outputs 113 for outputting one or more output signals. Controller 1000 or each controller 1000 also includes at least one memory device 114, which is electrically coupled to the at least one electronic processor 111 and has instructions 115 stored therein. The at least one electronic processor 111 is configured to access the at least one memory device 114 and execute the instructions 115 thereon.

[0079] Electronic processor 111, or each electronic processor 111, may include any suitable electronic processor (e.g., microprocessor, microcontroller, ASIC, etc.) configured to execute electronic instructions. Electronic memory device 114, or each electronic memory device 114, may include any suitable memory device and may store various data, information, thresholds, lookup tables or other data structures, and / or instructions therein or thereon. In embodiments, memory device 114 has information and instructions regarding software, firmware, programs, algorithms, scripts, applications, etc., stored therein or thereon that can manage all or part of the methods described herein. Processor or each electronic processor 111 may access memory device 114 and execute and / or use the instructions and information, or such instructions and information, to perform some or all of the functions and methods described herein.

[0080] At least one memory device 114 may include a computer-readable storage medium (e.g., a non-transitory or non-temporary storage medium), which may include any mechanism for storing information in a form readable by a machine or electronic processor / computing device, including but not limited to: magnetic storage media (e.g., floppy disk); optical storage media (e.g., CD-ROM); magneto-optical storage media; read-only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM and EEPROM); flash memory; or electrical or other types of media for storing such information / instructions.

[0081] The example controller 1000 has been described, including at least one electronic processor 111 configured to execute electronic instructions stored in at least one memory device 114, which, when executed, cause the electronic processor 111 to perform the methods described above. However, it should be understood that the invention is not limited to implementation by a programmable processing device, and that at least some and all of the functions and / or method steps of the invention in some embodiments can be equivalently implemented by non-programmable hardware, such as by a non-programmable ASIC, Boolean logic circuits, etc.

[0082] It should be understood that various changes and modifications can be made to this invention without departing from the scope of this application.

Claims

1. A control system for generating a speed limit signal for a vehicle, the control system comprising one or more controllers, said one or more controllers being configured to: Receive image data indicating the environment of the vehicle from one or more imaging devices associated with the vehicle; The speed limit indicated by the traffic sign and the position of the traffic sign relative to road features in the environment are determined based on the image data. The correlation between the speed limit and the vehicle is determined based on the determined location of the traffic sign and the determined location of the vehicle; Generate a flag speed limit signal indicating the speed limit based on the determined correlation; as well as The generated speed limit signal is output to at least one vehicle control system. The at least one road feature includes an entrance end to a bypass, and the one or more controllers are configured to determine the location of the traffic sign by determining the end distance from the traffic sign to the entrance end of the bypass.

2. The control system according to claim 1, wherein, The controller, or each controller, is configured to: Receive digital map data, the digital map data including indications of map speed limits associated with the road segment where the vehicle is located; and If the speed limit indicated by the traffic sign is determined to be irrelevant, a map speed limit signal indicating the map speed limit is generated and the map speed limit signal is output to the at least one vehicle control system.

3. The control system according to claim 2, wherein, If the speed limit indicated by the traffic sign is determined to be relevant, then the controller or each controller is configured to prioritize outputting the sign speed limit signal.

4. The control system according to any one of claims 1 to 3, wherein, Determining the location of the traffic sign includes determining the distance from the traffic sign to the road feature.

5. The control system according to claim 4, wherein, The controller, or each controller, is configured to determine the relevance of the speed limit based on whether the distance meets a predetermined criterion.

6. The control system according to claim 5, wherein, The road features include the edge of the road where the vehicle is located, and wherein identifying the location of the traffic sign includes determining the distance from the traffic sign to the edge of the road.

7. The control system according to claim 6, wherein, The one or more controllers are configured to determine that the speed limit is irrelevant to the vehicle if the determined distance to the edge of the road is greater than a predetermined threshold.

8. The control system according to any one of claims 1 to 3, wherein, The controller, or each controller, is configured to: Receive digital map data indicating map speed limits associated with the bypass; as well as If the speed limit matches the map speed limit associated with the bypass and the end distance is less than a predetermined end distance threshold, then the speed limit is determined to be irrelevant.

9. The control system according to any one of claims 1 to 3, wherein, The road features include additional traffic signs indicating the speed limit.

10. The control system according to claim 9, wherein, The one or more controllers are configured to: Whether the traffic sign and the other traffic sign cross the bypass is determined based on the position of the traffic sign relative to the other traffic sign. If the traffic sign and the other traffic sign cross the bypass, then the speed limit is determined to be irrelevant.

11. The control system according to any one of claims 1 to 3, wherein, The controller, or each controller, includes: An electrical input terminal is used to receive an electrical signal indicating the image data; An electrical output terminal, used to output an electrical signal indicating the speed limit; and One or more electronic processors are used to operatively execute computer-readable instructions to determine the relevance of the speed limit.

12. A vehicle comprising a control system according to any one of claims 1 to 11.

13. A computer-implemented method for generating speed limit signals for vehicle control, the method comprising: Receive image data indicating the environment of the vehicle from one or more imaging devices associated with the vehicle; The speed limit indicated by the traffic sign and the position of the traffic sign relative to road features in the environment are determined based on the image data. The correlation between the speed limit and the vehicle is determined based on the determined location of the traffic sign and the determined location of the vehicle; Based on the determined correlation, a flag speed limit signal indicating the speed limit is selectively generated; as well as Selectively generated signals are output to at least one vehicle control system. The at least one road feature includes an entrance end to a bypass, and the one or more controllers are configured to determine the location of the traffic sign by determining the end distance from the traffic sign to the entrance end of the bypass.

14. A computer-readable medium comprising computer software, which, when executed, causes to perform the method of claim 13.

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