Patent Application
20120109521
1. Field
A system and method are provided to enhance current lane departure warning systems with lane-level position information that can be integrated with GPS navigation functionality to enable enhanced lane guidance.
2. Description of the Related Art
Current GPS systems give directions and traffic alerts but do not indicate a vehicle's lane position on a roadway or utilize that information to further assist a vehicle operator with directional information.
Commercial GPS devices (e.g., TomTom GO 950) provide lane guidance to indicate the appropriate lane to be in for an upcoming exit or turn but cannot detect the lane the vehicle occupies and recommend the required lane changes at appropriate distances from the impending exit or turn. Lane-level positioning capability integrated with the GPS device can create a lane-level navigation system to advise the driver which lane should be chosen to reach the specified destination without requiring excessive last-minute lane changing.
In road-transport terminology, a Lane Departure Warning (LDS) system is a mechanism designed to warn a driver when the vehicle begins to move out of its lane without utilizing a turn signal on freeways and arterial roads. These systems are designed to minimize accidents by addressing the main causes of collisions: driving error, distraction, and drowsiness. In 2009, the NHTSA began studying whether to mandate lane departure warning systems and frontal collision warning systems on automobiles. Currently, there are two main types of lane departure warning systems: systems which warn the driver if the vehicle is leaving its lane with visual, audible, and/or vibration signals, and systems which warn the driver and automatically take corrective actions if the driver fails to respond to the warnings.
The first production lane departure warning system in Europe was developed by the Iteris, Inc. for Mercedes Actros commercial trucks in 2000 and is now available on most trucks sold in Europe. In 2002, the Iteris system became available on Freightliner Trucks vehicles in North America. In these systems, the driver is warned of unintentional lane departures by an audible rumble strip sound generated on the side of the vehicle drifting out of the lane. If a turn signal is used, no warnings are generated.
Most lane departure systems rely on optics and sensors to determine a vehicle's position relative to road markings. In 2005, the combined effort of Visteon and University of Michigan Transportation Research Institute (UMTRI) integrated radar and other technology to provide a more comprehensive driver assistance system. Dubbed “Road Departure Crash Warning” (RDCW) technology, the system warns drivers drifting out of their lane and helps drivers adjust speed for negotiating curves.
The RDCW system provides two distinct modes of driver warning that are designed to minimize nuisance and gain credibility with the driver for the time when a road departure warning is truly needed. The first type of warning is to prevent the drift-off-road problem that arises from inattention or drowsiness. A second type of warning is to alert a person who is driving too fast for an upcoming curve. The RDCW system does not intervene in vehicle control.
UMTRI's “lateral drift warning” function operates in similar fashion to other lane departure warning systems in that it relies on a forward-looking video camera in order to measure vehicle position and lateral velocity relative to lane and road-edge markings. However, the system adds another layer of sophistication through the use of four radar units mounted in the front fascia and side of the vehicle. These forward and side facing radar units assess the room available on the shoulder for performing a recovery maneuver. When ample room is present, warnings are delayed to avoid nuisance alarms that often result from early warnings. However, when little room is available, the warnings are given early so that the driver has enough time to respond and avoid a crash.
When drift-off is detected, the system provides audio, visual, and seat vibration warnings. Drivers receive either a cautionary or imminent alert, based on lane position, lateral movement, and the type of lane boundary. A cautionary alert occurs when the driver is crossing a dashed-line boundary with no vehicles in the drift path. The alert appears as a yellow icon on the dashboard display and as a vibration on the left or right side of the driver's seat, depending on the direction of lateral drift. An imminent alert occurs when the driver approaches or has crossed a solid-line boundary or when crossing a dashed-line boundary while a vehicle is present in the drift path. A red icon appears on the display and a buzz sounds on the side of the vehicle at which the threat is developing.
The system becomes inactive in the following conditions: on unpaved roads, roads with poor lane markings or badly defined road edges, and at speeds below 25 mph. Warnings are not issued when a lane change is preceded by a driver engaging a turn signal.
On the UMTRI test vehicles, more than 300 channels of data are collected every tenth of a second, including vehicle speed, lane position, location of lane and road edges and objects around the vehicle, plus many signals indicating the driver's actions and the state of the vehicle. Data are gathered from radar sensors pointing toward the front and sides of the vehicle, video cameras pointed through the windshield and at the driver's face, and by means of several other instruments that monitor the motion of the vehicle and whether a cell phone is in use. The data acquisition system automatically sends a data sample from the vehicle to the UMTRI facility, via a cell modem, each time the ignition is turned off. A comment button, installed in the dashboard, allows drivers to record comments and suggestions any time they drive.
Vision based lane recognition systems are relatively mature and have already been introduced to market for lane departure warning and other systems. However, both systems have some limitations.
A system and method for an integrated lane positioning monitor with locational information systems is provided. The system and method gather and process information and data to assist an automobile operator in selecting and changing driving lanes. Further, the system and method is integrated with a locational information system to inform the operator of upcoming congestion and traffic issues as well as an appropriate distance to change lanes before a highway exit or entrance.
In one aspect of the present invention, a method for integrating a locational information system with a lane position monitor is provided. The method includes transmitting a series of driving directions to a vehicle operator via a locational information system based on a destination inputted by the operator. The driving directions may be transmitted by audible sounds and visual indications.
The method further includes processing image and data captured by at least one sensor to determine which particular lane of a series of lanes a vehicle occupies on a roadway. The step of the method may include taking a series of photographs to determine lane markings substantially parallel to the vehicle and further determine the number of lanes on a roadway on each side of the vehicle.
The method also includes determining an appropriate lane that should be occupied based on a particular driving direction and comparing the appropriate lane to the occupied lane.
In another aspect of the invention, the method includes analyzing vehicle speed, location, and distance from a position where the operator must make a maneuver, such as a turn, and determining the appropriate position for a lane change based on the location and speed of the vehicle. The method also includes determining whether vehicles in adjacent lanes would interfere in the ensuing lane change. In an instance where a vehicle must make multiple lane changes to enter the appropriate lane, the method includes determining multiple positions for the multiple lane changes.
In another aspect of the invention, the method includes transmitting at least one lane switch direction to the vehicle operator at a distance before the maneuver is to be completed.
The invention also relates to a system for providing lane positioning information is provided. The system includes a locational information system, such as a Global Positioning System (GPS), to determine the vehicle's position within a network of roadways. The locational information system provides a vehicle operator with detailed driving directions based on a desired destination inputted by the operator. In some instances, the locational information system will also provide real time road congestion, traffic, and construction information received from a local or national network.
The system also includes a lane position monitor having at least one lane position sensor to determine a vehicle's relative position on a roadway. In the preferred embodiment, the at least one lane positioning sensor comprises several cameras mounted on a front position and on sides of the vehicle. The cameras take photographs of lane markings at predetermined intervals. In other embodiments, the sensor can be in the form of radars, lasers, and other known devices. Further, the system includes at least one sensor to determine if an adjacent lane is occupied by one or more vehicles that could interfere with driving maneuvers.
A computer is provided and is in communication with the locational information system and the cameras. Digital image acquisition software is provided on the computer. The digital image acquisition software analyzes images from the cameras and tracks the continuity of the lane markings. The digital image acquisition software determines the lane the vehicle occupies based on the relative position of lane markings on the road.
The locational information system informs the operator when appropriate driving maneuvers are necessary by giving audio and visual warnings. For instance, the locational information system may announce, “Exit right in one mile” when the driver is one mile from a highway exit. The locational information system also monitors the vehicle speed.
The computer analyzes the locational information system data along with the images captured by the digital image acquisition software to determine whether the operator is in the appropriate lane for an upcoming driving maneuver and inform the operator if and when a lane switch is necessary. For instance, if the operator is required to use an exit ramp on the right of the highway in one mile, the operator should enter the right lane at a comfortable distance before the exit. If the operator occupies the left lanes, the computer will recognize the vehicle's position and compute an appropriate time and position to change lanes based on the distance to the exit calculated by the locational information system, and inform the driver of this information.
The above and other aspects, features, and advantages of the disclosure will become more apparent in the light of the following detailed description when taken in conjunction with the accompanying drawings in which:
Preferred embodiments of the disclosure will be described herein with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the disclosure.
Embodiments of the present disclosure overcome the shortcomings of existing practices and provides a system and method for integrating lane position monitoring and locational information systems.
Referring to
The computer processor 102 will use computer software instructions that have been programmed into the computer processor 102 and conventional computer processing power to interact and organize the traffic flow between the various other modules, sensors, etc. of the vehicle. It is to be understood that the present disclosure may be implemented in various forms of hardware, software, firmware, special purpose processors, or a combination thereof. A system bus 104 couples the various components shown in
It is to be further understood that because some of the constituent device components and method steps depicted in the accompanying figures may be implemented in software, the actual connections between the device components (or the process steps) may differ depending upon the manner in which the present disclosure is programmed. Given the teachings of the present disclosure provided herein, one of ordinary skill in the related art will be able to contemplate these and similar implementations or configurations of the present disclosure.
In the preferred embodiment, the sensors 100 are comprised cameras mounted on an exterior surface of the vehicle. For instance, in the preferred embodiment, the cameras 100 comprise left side cameras 100L mounted on a left side of the vehicle 104 and right side cameras 100R mounted on the right side of the vehicle 104. The side cameras 100L, 100R are positioned to provide images of lane markings 200. Additionally, in the preferred embodiment, a front camera 100F is mounted at a forward position of the vehicle 10. The present disclosure should not be limited to this embodiment. The sensors can also consist of a radar systems, night vision cameras, lasers systems, electro-magnetic sensors or other known devices capable of providing lane marking information to the central processor.
Frame grabbers are used to acquire images. The side cameras 100L, 100R, 100F are arranged to capture an image at assigned distance intervals. For instance, the cameras 100L, 100R, 100F may be set to capture one image for every one meter the vehicle 104 travels. The side cameras 100L, 100R are synchronized so that there is some duplication within the images. For instance, in the preferred embodiment, approximately sixty percent of the images captured by the left cameras 100L will be duplicative. The duplication of areas of the images allows the computer processor 102 to monitor the continuity of the lane markings 180. In this way, the computer processor 102 is able to recognize if the vehicle 104 switched lanes. Additionally, by measuring the continuity of lane markings 180, the computer processor 102 can recognize if there has been a change in the number of lanes on the roadway, or if there is a merger between adjacent lanes approaching. At least one sensor 100 is mounted on the vehicle 104 and is configured to identify and map the location of vehicles in surrounding lanes. The at least one sensor 100 may consist of a radar system, night vision cameras, laser systems, electromagnetic sensors, or other known devices capable of identifying surrounding vehicles. In one embodiment, the at least one sensor 100 is integrated with the cameras 100L, 100R, 100F.
A locational information device 150, such as a Global Positioning System (GPS), also is provided. The GPS 150 is connected to a communication network, such as a satellite relay or wireless network 160, to determine the exact position of the vehicle 10 within a network of roads. The GPS 150 has a display screen 152 visible to the operator of the vehicle 10 displaying the vehicle's 104 position on the network of roads. The GPS 150 further has a user interface, such as a touch screen, to allow the vehicle operator to enter a driving destination. The display screen displays detailed driving instructions to direct the driver to a specified destination. Additionally, the GPS 150 gives verbal cues and maps to inform the driver of impending driving maneuvers.
The control unit 102 collects and synchronizes information from the sensors 100 and the GPS 150. The control unit 102 extracts information from the GPS 150 relating to the exact position of the vehicle 104 within the network of roads. The control unit 104 also obtains information relating to the vehicle's 104 speed and the distance until a driving maneuver is required.
The sensors 100 provide the control unit 102 with continuous data. Specifically, the sensors 100 provide information relating to the number of lanes on the roadway and the vehicle's 104 relative position among the lanes.
The control unit 102 analyzes the data from the sensor 100 and the GPS 150 to inform the operator if a lane change is necessary. The control unit 102 and the GPS 150 will determine the next driving maneuver and whether there is a preferred or necessary lane for the driving maneuver. The control unit 102 will compare this information to the lane position data from the sensors 100. In the event that the driver occupies the preferred lane, the external synchronization device will not signal the operator.
If the vehicle 104 is not in the preferred lane, the control unit 102 will signal the driver and inform the driver of the preferred lane. The signal is typically in the form of an audible sound. However, a visual signal can also be used to alert the operator of a required lane change. The visual signal can also be integrated into a map shown on the display 152. Additionally, based on the speed of the vehicle 104, the control unit 102 will inform the operator that a maneuver is required at a predetermined distance. For instance, a vehicle 104 traveling sixty-five miles per hour will need more time to switch lanes than a vehicle 104 traveling fifty miles per hour. Further, a vehicle 104 exhibiting signs of ‘stop-and-go” traffic (i.e. slow, short-distance travel followed by complete slowdown), will be given a longer distance to switch lanes due to the difficulty and complexity involved with switching lanes during a traffic situation.
With reference to
While the disclosure has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims.
This application claims priority on U.S. Provisional Application No. 61/407,183 filed on Oct. 27, 2010.
| Number | Date | Country | |
|---|---|---|---|
| 61407183 | Oct 2010 | US |
