Patent Publication Number: US-2017351263-A1

Title: Roadway-Infrastructure-Maintenance System Using Automated Vehicles

Description:
TECHNICAL FIELD OF INVENTION 
     This disclosure generally relates to a roadway-infrastructure-maintenance system using automated-vehicles, and more particularly relates to a system configured to determine a need-for-maintenance of the infrastructure-feature. 
     BACKGROUND OF INVENTION 
     It is known that an automated-vehicle detects infrastructure-features such as lane-markings, light-color emitted by a traffic-signal, and roadway-signs in order to determine how the automated-vehicle, i.e. a self-driving vehicle, should be operated. For example, the automated-vehicle travels through an intersection when the traffic-signal is green, and the automated-vehicle stops when the traffic-signal is red. Furthermore, consistent and visible lane-markings are particularly helpful to operate an automated-vehicle. However, normal wear, aging, and/or damage by a natural disaster or a collision with a vehicle may make it difficult or impossible for an infrastructure-feature to be detected. 
     SUMMARY OF THE INVENTION 
     In accordance with one embodiment, a roadway-infrastructure-maintenance system using automated-vehicles to maintain a roadway is provided. The system includes an image-device and a controller. The imaging-device is suitable to mount on a host-vehicle. The imaging-device is used to detect an infrastructure-feature proximate to a roadway traveled by the host-vehicle. The controller is in communication with the imaging-device. The controller is configured to determine a need-for-maintenance of the infrastructure-feature. 
     Further features and advantages will appear more clearly on a reading of the following detailed description of the preferred embodiment, which is given by way of non-limiting example only and with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The present invention will now be described, by way of example with reference to the accompanying drawings, in which: 
         FIG. 1  is a diagram of a map-data update system in accordance with one embodiment; and 
         FIG. 2  is a traffic scenario encountered by the system of  FIG. 1  in accordance with one embodiment. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates a non-limiting example of a roadway-infrastructure-maintenance system, hereafter referred to as the system  10 . As will be explained in more detail below, the system  10  makes use of the object-detections abilities found in most examples of autonomous or automated-vehicles, in this case represented by a host-vehicle  12 . The system  10  uses those abilities to help identify instances of infrastructure-features such as lane-markings, traffic-signals, roadway-signs, and/or street-lights in need of repair and thereby help to maintain a roadway. In one embodiment, the host-vehicle  12  is characterized as an automated-taxi (not shown). That is, driverless vehicles that do not have operator controls may be used to search for instance where infrastructure-features are in need of maintenance, including, but not limited to, determining that snow-removal services are needed. 
     The system  10  includes an imaging-device  14  suitable to mount on the host-vehicle  12 . In general, the imaging-device  14  is used to detect one or more instances of objects  20  proximate to a roadway  18  ( FIG. 2 ) traveled by the host-vehicle  12 . The system  10  determines which of the objects  20  may be an infrastructure-feature  16 . By way of example and not limitation, the imaging-device  14  may include any one or any combination of a camera, a radar-unit, and a lidar-unit, or any other device suitable to detect the objects  20  proximate the roadway  18  that are an instance of the infrastructure-feature  16  and may be in need of maintenance. 
       FIG. 2  illustrates a non-limiting example of a traffic-scenario  22  encountered by the host-vehicle  12 . One non-limiting example of the infrastructure-feature  16  is a lane-marking  24  which may be used by the system  10  as a guide by which the system  10  steers the host-vehicle  12  via the vehicle-controls  58  ( FIG. 1 ) of the host-vehicle  12 . The lane-marking  24  is typically formed of paint that includes light reflective characteristics that make the lane-marking  24  readily detectable using the camera and or the lidar-unit of the imaging-device  14 . A crosswalk-marking  26  may also be detected by the imaging-device  14 , and the presence of the crosswalk-marking  26  may be used by the system  10  to search for and more readily identify the presence of, for example, a pedestrian  28  and/or a crossing-guard  60 . That is, because the presence of the crosswalk-marking  26  is detected, the identification and/or classification of the objects  20  can be more reliably performed because the object-identification algorithms can be tuned or selected to more readily identify the pedestrian  28  and/or the crossing-guard  60 . 
     Because the quality of the lane-marking  24  and the crosswalk-marking  26  is important to the operation of the host-vehicle  12 , the system  10  advantageously is configured to evaluate the quality of the lane-marking  24  and the crosswalk-marking  26 , and determine when there is a need-for-maintenance  30  of the infrastructure-feature  16 , in this example the lane-marking  24  and the crosswalk-marking  26 . 
     Accordingly, the system  10  includes a controller  32  in communication with the imaging-device  14 . The controller  32  may include a processor (not specifically shown) such as a microprocessor or other control circuitry such as analog and/or digital control circuitry including an application specific integrated circuit (ASIC) for processing data as should be evident to those in the art. The controller  32  may include memory (not specifically shown), including non-volatile memory, such as electrically erasable programmable read-only memory (EEPROM) for storing one or more routines, thresholds, and captured data. The one or more routines may be executed by the processor to perform steps for determining when the infrastructure-feature  16  exhibit&#39;s the need-for-maintenance  30  based on signals received by the controller  32  from the imaging-device  14  as described herein. 
     In order for the system  10  to more readily detect the presence of an instance of the infrastructure-feature  16 , the system  10  or more particularly the controller  32  may include a digital-map  34  that indicates an expected-presence  36  of the infrastructure-feature  16 . The system  10  may include a location-device  38  such as a global-positioning-system-receiver (GPS-receiver) so that a map-location  40  on the digital-map  34  can be determined. If the system  10  or the controller  32  is unable to or has difficulty detecting the expected-presence  36  of the infrastructure-feature  16  at the map-location  40 , then that may be an indication that the need-for-maintenance  30  is indicated when the infrastructure-feature  16  is not-detected as expected. For example, if the lane-marking  24  and/or the crosswalk-marking  26  are not detected or do not appear with sufficient contrast to the surface of the roadway  18 , then that may be in indication of the need-for-maintenance  30 . The cause may be that the paint used for the lane-marking  24  and/or the crosswalk-marking  26  is worn, or they may be covered by ice, snow, mud, or other debris that should be removed. 
     In order for the system  10  to communicate the need-for-maintenance, the system  10  includes a transmitter  42  in communication with the controller  32 . The transmitter  42  may be used to communicate the need-for-maintenance  30  to a maintenance-organization  44  such a county road-commission or other suitable government agency, which may eventually lead to a maintenance-request  46  being issued by the maintenance-organization  44  to dispatch the necessary persons and/or equipment to address the need-for-maintenance  30 . In order to prevent spoofing or malicious activity that wastes the resources of the maintenance-organization  44 , the maintenance-request  46  may not be issued until a request-count  48  is greater than some threshold, greater than five for example, arising from multiple instances of the need-for-maintenance  30  for the same infrastructure-feature  16  being received. The maintenance-organization  44  may also maintain a map-database  50  which may be used to periodically update the digital-map  34 . 
     By way of further non-limiting examples, the infrastructure-feature  16  may be a traffic-signal  52 , a roadway-sign  54 , or a street-light  56 . The controller  32  may be configured to determine an operational-state  62  of, for example, the traffic-signal  52  and/or the street-light  56 , and issue a need-for-maintenance  30  if either is found to be out of operation. Similar to detecting the quality of the lane-marking  24 , signals or information from the imaging-device  14  may be used to determine the reflectivity and/or apparent contrast of the roadway-sign  54 , and issue a need-for-maintenance  30  if the roadway-sign is difficult for the imaging-device to read or detect. If an instance of the infrastructure-feature  16  has been removed because of, for example, the presence of a construction-zone  64  so that the infrastructure-feature  16  is characterized as not-detected  66  by the system  10 , the maintenance-organization  44  may receive a need-for-maintenance  30  but ignore it because the construction-zone  64  is very-temporary. If the construction-zone is expected to be present for a relatively long time, more than a week, then the maintenance-organization may elect to update the map-database  50  to stop the issuance of the need-for-maintenance  30  from the host-vehicle  12 . 
     Accordingly, a roadway-infrastructure-maintenance system (the system  10 ), a controller  32  for the system  10  and a method of operating the system  10  is provided. The system  10  advantageously makes use of various imaging devices available on automated-vehicles to more quickly detect when the need-for-maintenance of an infrastructure-feature  16  is needed. 
     While this invention has been described in terms of the preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow.