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DEDUCTIVE SYSTEM FOR THE RIGHT OF PREFERENCE WITH LONG DISTANCE AND CLEARANCE OF CORRIDOR FOR EMERGENCY RESPONSE
FIELD OF THE INVENTION The present invention relates in general to traffic signal control systems and more specifically to traffic signal preference systems. BACKGROUND OF THE INVENTION Traffic signs are vital for managing the flow of traffic. The coordination of traffic signals using the control systems of traffic signals can greatly facilitate congestion. However, certain emergencies may need to give preference to traffic signals to accelerate the passage of an emergency vehicle to its destination. Several systems have been proposed to achieve preference for a traffic signal when an emergency vehicle approaches an intersection. These systems use a variety of communication techniques to transport information between the vehicle and the intersection including optical signals and signals of wireless or radio-transmitted communication. BRIEF DESCRIPTION OF THE INVENTION The embodiments of the present invention make it possible to give preference to intersections along Ref. 171220 2
of a corridor for emergency vehicles. In one aspect of the present invention, the right-of-preference broker can clear traffic from the emergency vehicle route, which increases the speed at which the vehicle can travel along the corridor. One embodiment of the present invention includes a microcontroller configured to receive the preemption requests anticipated from a network. In addition, the microcontroller is configured to evaluate the information included in a preemption request against a predetermined set of criteria and the microcontroller is configured to preempt a sequence of traffic signals when the information anticipated in a right request. preferably it satisfies the predetermined set of criteria. The network can be a wired or wireless network. An additional embodiment also includes an intersection controller having right-of-preference entries, a long distance preference right module which is connected to the right-of-way entries of the intersection controller and which includes the microcontroller and a transceiver and a right-of-way device connected to the long distance preference right module. Another embodiment of the invention includes a 3
intersection controller including the microcontroller and having right of preference entries, a right-of-way device connected to the intersection controller by means of the right-of-preference inputs and a transceiver connected to the intersection controller. In a still further embodiment, the preemption request is anticipated from a traffic signal controller that includes an intersection controller, the traffic signal controller is located at an intersection with the right of preference and the request for Pre-emptive right includes information that refers to the geographical location of the right-of-way intersection and the status of the right-of-way tickets of the intersection's driver, from the intersection to the right of preference. In still another embodiment, the request for the right of early preference was generated in response to a vehicle with a right of preference and the microprocessor is configured to evaluate the information by generating an estimated time of arrival for the vehicle with the right of preference using a speed window. In addition, the microprocessor can be configured to evaluate the information by determining the speed window based on the present traffic conditions.
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In a still further embodiment, again, the microprocessor is configured to resolve preemption requests made directly to the driver of the traffic signals by a vehicle and the anticipated preemption requests. In addition, the vehicle's preemption right request and the preemption right request request may include priority information and the microprocessor may be configured to give preference to a sequence of traffic signals in a manner consistent with the right of preference request. of highest priority. Yet another embodiment of the invention includes a plurality of traffic signal controllers. In addition, at least one traffic signal controller includes a preemption device that can be activated in the right of preference by a vehicle equipped with hardware capable of communicating a preemption request to the right of preference device, the traffic signal controller is configured to send pre-emptive preference requests via a network and at least one of the traffic signal controllers is configured to receive the pre-emptive preference request by means of the net. In addition, the network can be wired or wireless. One embodiment of the method of the present invention 5
includes receiving a preemptive right request from another intersection, determining whether the preemption right request meets at least one predefined criterion, determining whether the preemption right request is in conflict with any preemption claim that is commonly respected by the intersection, and when the preemptive right request meets the predefined criteria and is not in conflict with the other preemption requests, give preference to the intersection and anticipate the preemption request to neighboring intersections. In addition, the right of preference application may include information that refers to the geographic location of the intersection that is the source of the right of preference application and the manner in which the right-of-preference intersection has been provided with the right. preferably. In a further embodiment of the method of the invention, the request for early preference was originated at an intersection of origin. In addition, the determination that if the right of advance preference request satisfies at least one predefined criterion involves the determination that if the origin intersection is within a predetermined distance of the intersection.
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In another embodiment of the method of the invention, a vehicle will have the right of preference at an intersection of origin at which it anticipated the request for preference right. In addition, the determination that if the right of advance preference request satisfies at least one predefined criterion involves the determination that if the vehicle will reach the intersection with sufficient probability. In a still further embodiment of the method of the invention, a vehicle is provided with the right of priority over an intersection of origin to which it preempted the preemption request. In addition, the determination that if the pre-emptive preference request satisfies at least one predefined criterion involves the determination that if the vehicle will reach the intersection within a predetermined time. In yet another embodiment of the method of the invention, the preemption right request is assigned as a priority, other preemption requests are also assigned as priorities and the determination that if the request for advance right is in conflict with any application of the right of preference that is commonly respected by the intersection, includes the determination that if the right
Pre-emptive preference is of a higher priority than all other preemption requests. In a still further embodiment of the method of the invention again, the other preemption requests may include at least one preference right request made directly to the intersection by a vehicle. In addition, the other preemption requests may include at least one other preemption right request at the intersection by another intersection. In yet another embodiment of the invention, giving preference to the intersection comprises establishing both traffic signals and pedestrians in accordance with the preemption request. In a still further embodiment of the method of the invention, anticipating the preemption request to nearby intersections involves broadcasting the preemption request over a wireless network and / or sending the preemption request to neighboring intersections via from a wired network. BRIEF DESCRIPTION OF THE FIGURES Figure 1 is a schematic diagram of a right of preference system according to one embodiment of the present invention; Figure 2 is a semi-circuit diagram
schematic of a traffic signal controller according to the present invention that includes a traditional right of preference system and a long distance preference right module; Figure 3 is a flow chart illustrating a process according to one embodiment of the present invention for achieving the long distance preference right of a distant intersection; Figure 4 is a flow chart illustrating the resolution of conflicts between local preference right applications and long distance preference requests; Figure 5 is a schematic diagram illustrating the impact that a traffic control system, according to one embodiment of the present invention, can have on the traffic flow; Figure 6 is a semi-schematic circuit diagram of a mode of a traffic signal controller according to the present invention that includes an intersection controller and a long distance preference right module; Fig. 7 is a semi-schematic circuit diagram of a mode of a traffic signal controller according to the present invention that includes an intersection controller and a right-hand module;
long distance preference that is connected to a wired network; Figure 8 is a semi-schematic circuit diagram of a mode of a traffic signal controller according to the present invention that includes an intersection controller programmed in accordance with the present invention and connected to a right-of-preference device. and a transceiver; and Figure 9 is a schematic circuit diagram of a mode of a traffic signal controller according to the present invention that includes an intersection controller programmed in accordance with the present invention and connected to a right-of-way device and a wired network. DETAILED DESCRIPTION OF THE INVENTION The embodiments of the present invention include a right of preference system capable of giving preference to traffic signals from an intersection to the incoming and long distance preference right modules at distant intersections. The long distance preference right modules are able to give right of preference to the traffic signals of the distant intersection in response to the right of preference of the intersection to which it is going to arrive. In one aspect of the invention, the right of long-distance preference is 10
used to clear runners along the routes that a vehicle with the right of preference is likely to follow. The right of long distance preference can accelerate the passage of the vehicle by clearing the congestion on its route. Turning now to the figures, a right of preference system in accordance with the present invention is illustrated in Figure 1. The right of preference system 10 includes a vehicle with the right of preference 12 equipped with hardware (not shown) capable of communicating with and giving right of preference to the traffic signals 14 of an intersection 16 to which it is going to arrive. The intersection that is to be reached includes traffic signals that are controlled by a traffic signal controller (not shown). The traffic signal controller is equipped with a right-of-way system capable of receiving communications from the vehicle with the right of preference and giving preference to traffic signals in response to received communications. The traffic signal controller is also capable of communicating with the traffic signal controllers at distant intersections 18. The communication of the controller's preemption right of the traffic signals at an intersection to which it is to arrive may lead to grant preference to traffic signals at distant intersections. In 11
In one embodiment, traffic signal controllers at distant intersections are programmed to create a corridor with preemptive right 20, which leads to the preferential right of traffic signals 22 in the most probable direction of travel of the vehicle with right of way. preference. In addition, the modalities may also give right of preference to the traffic signals 24 along the side streets 26 to the corridor with the right of preference to facilitate the clearing of the traffic congestion 28 from the right-of-preference corridor. Although the runner with the right of preference is illustrated as a direct route, in other modalities the runner with the right of preference may not be a straight route. The hardware mounted on the vehicle with the right of preference that is able to communicate with and give right of preference to the traffic signals of an intersection to which it is going to arrive, can be implemented using a suitable hardware of any right system of known preference. In one embodiment, the hardware described in the U.S. patent application. No. 10 / 811,075 can be used to implement the hardware on the vehicle with the right of preference. The description of the U.S. patent application No. 10 / 811,075 is incorporated herein for reference in its entirety. In other modalities, other right-of-preference techniques based on GPS (System of 12
Global Positioning) can be used. In several embodiments, the preferred optical rights techniques are such as those used in the Opticon system manufactured by the 3M Company of St. Paul, Minnesota. Other modalities may use right-of-preference systems based on sirens. The implementation of the modalities of the traffic signal controllers according to the present invention is further described below. One embodiment of a traffic signal controller according to the present invention is illustrated in Figure 2. The traffic signal controller 30 includes an intersection controller 32. The intersection controller is connected to a right-of-way device 34 and a long-distance preference-right module 36 by means of a disconnect interface 38. In one embodiment, the intersection controller is a conventional intersection controller. such as a NEMA controller. TS2 M52 manufactured by Siemens ITS of Austin, Texas, which possesses a plurality of right-of-preference entries. Preferred right inputs are used to receive signals from external devices that instruct the controller of the intersection to disconnect from the regular progress of the signal. The 13
Preferred right entries also indicate to the intersection driver the traffic signals that must be displayed during the right-of-preference period. In other modalities, other intersection controllers capable of being provided with the right of preference may be used. For example, the intersection controller can be implemented using other types of controllers such as 170, 270 and other standard NEMA (North American Electrical Manufacturers) controllers. The right-of-way device can be implemented using the intersection hardware of any right-of-preference system. Known preemption systems provide electronic devices to receive information from vehicles with a right of preference and are able to decide whether the right of preference should occur or should be granted. Such systems also include the functionality to provide input signals to the intersection controller necessary to give the right of preference to the intersection in the manner required by the vehicle with the right of preference. In one embodiment, the intersection hardware described in the U.S. patent application. No. 10 / 811,075 can be used to implement the right-of-preference device.
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In the traffic signal controllers according to the present invention, the outputs of the right-of-way device are directed through the long distance preference right module. The long-distance preference right module provides signals to the intersection controller to give the right of preference to the intersection in response to the signals generated by the right-of-way device and / or in response to the signals received from the intersections. neighbors. The long-distance preference right module is also responsible for resolving conflicts between the different right-of-preference requirements of a preferred right application communicated through the right of preference device and a requested concurrent right of preference received from a next intersection. In one embodiment, the long distance preference right module includes a microcontroller 40 which is connected to a transceiver 42. The microcontroller receives the input signals from the right-of-way device and the transceiver. The microcontroller provides output signals to the intersection controller and the transceiver. In various embodiments, the microcontroller can also receive input signals from the intersection controller to verify the state of the intersection.
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The transceiver communicates with nearby intersections. The transceiver can receive messages from nearby intersections that inform of their right of preference. In the event that the intersection is granted with the right of preference to a vehicle that is approaching, the transceiver can send messages to nearby intersections informing them that it has been granted the right of preference. In one embodiment, the microcontroller is implemented using an LP3100 device manufactured by ZWorld of Davis, California. In other embodiments, any suitable microcontroller or combination of processing elements can be used to implement the microcontroller 40. In one embodiment, the transceiver is implemented using broad spectrum radio equipment manufactured by Freewave Technologies of Boulder, Colorado. In other embodiments, electronic devices designed to use one of the many wireless or wired protocols may be used for communication between traffic signal controllers at nearby intersections. As described above, a disconnect interface is used to direct the signals between the device with the right of preference up to the module 16.
long-distance preference right and between the long distance preference module and the intersection driver. In one embodiment, a common PC board with busbar connectors is used to establish the necessary connections between the electrical interfaces. In other modalities, other techniques to build the customary connectors can be used. In one embodiment, the customary connector is constructed to meet NEMA TS 1 and TS 2 standards. Turning now to FIG. 3, a flow chart illustrating a process for anticipating a long-distance preference request to a controller. of traffic signals located at a distant intersection, is illustrated. Process 50 begins with the right of preference (52) of an intersection for a vehicle with the right of preference. The controller of the traffic signals at the intersection with the right of preference then anticipates (54) the right of preference information to the controls of the traffic signals at the distant intersections. In one embodiment, the right of preference information includes an identifier of the intersection for the intersection with the right of preference granted, the geographical position of the intersection with the right of preference granted and the
state of the totality of the address entries of the right of preference up to the controller of the intersection, of the intersection with the right of preference granted. In another modality, additional information or alternative routes for characterizing the above information can be communicated. The controller of the traffic signal at the distant intersection initially determines whether the preemption request is a request that has already been anticipated thereto. If not, then the traffic signal controller works in response to the preference request. Otherwise, the preemption request is ignored. The traffic signal controller at the distant intersection uses the anticipated information to determine (56) whether the distant intersection is close enough to the intersection with the right of preference to guarantee the right of preference of the distant intersection as well. If the distant intersection is located at a distance from the intersection with the right of preference that is greater than a predefined maximum distance, then the distant intersection is not granted with the right of preference (58). If the distance is less than the maximum distance, then the controller of the traffic signals at the distant intersection determines (60) whether the vehicle with 18
Right of preference is likely to pass through the distant intersection. In one embodiment, the traffic signal controller determines the statistical probability that the vehicle will eventually reach the distant intersection. This calculation can use the information that refers to whether the distant intersection lies within a corridor with the right of preference and the distance of the intersection along a side street if it is not within the corridor with the right of preference. In other modalities, other techniques may be used to determine if the vehicle is likely to travel through the distant intersection including the use of historical information that refers to the route traveled by the vehicles with preemptive rights that have been granted the right of preference over the intersection with the right of preference. In one mode, statistical calculations involve the use of an expected speed of a vehicle on a given street near the given intersection. For each traffic signal controller at each distant intersection, a speed "window" factor is used for each direction to which it will arrive: Vmin is the minimum expected speed of a vehicle and Vmax is the maximum expected speed of a vehicle. A vehicle. These intersections use the best-known, final position of 19
vehicle that is anticipated by the intersections to which it is going to arrive, equipped with a hardware of right of conventional preference. This is calculated more frequently on the basis that when the right-of-preference system stops the activation of an intersection that will be reached because it passes through the intersection (as with optical systems). The intersection at which you will arrive records the time and position of the junction and anticipates it at distant intersections. The position can also be calculated using the location information of the GPS preference right systems. When a distant intersection receives the position information, it starts a stopwatch. It uses the known distance between itself and the intersection to which it is going to arrive, combined with the "window" of speed to determine a window of time that will give the right of preference. For example, the intersection A is equipped with an optical preference system, conventional and the intersection B is equipped only with the right of advance preference. Also, intersection A and intersection B are at a distance of 304.8 meters (1000 feet), and the "window" speed for this route is between 25 MPH (40 feet / second) and 50 MPH (80 feet / second). ). An emergency vehicle approaches and crosses the intersection A, 20
which identifies that the optical trigger is interrupted, records the time and position of the crossing, and anticipates the information to the intersection B. During the reception of the anticipated activation, the intersection B starts a chronometer of the "window". Based on the distance, intersection B will begin to grant the right of preference when the timer exceeds 12.5 (1000/80) seconds, and will stop the right of preference when the timer exceeds 25 seconds. Some tolerance time can also be applied. The more advanced versions of this mode can be adjusted to the "window" of speed based on factors such as the time of the day, the day of the week, the information of dynamic congestion (provided by the intersection controllers), or the information of Priority priority for the vehicle. If the controller of the traffic signal at the distant intersection determines (60) that the vehicle with the right of preference is not likely to travel through the distant intersection, then the distant intersection is not activated for the right of preference (58) . When the traffic signal controller determines (60) that the vehicle with the right of preference is likely to travel through the distant intersection, then the traffic signal controller determines (62) whether to grant the right of preference to the distant intersection could 21
create a conflict with any other right of preference requests. The resolution of preemptive right claims in conflict is well known and typically involves determining which request has been assigned the highest priority by the system and which application will be respected. If another right of preference request has a higher priority than the right of advance preference request, then the traffic signal controller will not grant the right of preference at the intersection of the manner requested in the right of advance preference request. Instead, the traffic signal controller of the distant intersection anticipates (64) the right-of-preference request to its next intersections. If the preemptive right request for the intersection granted with the preemptive right is the highest priority preference request, then the traffic signal controller grants the right of preference (66) at the distant intersection of the manner required by the pre-emptive right request application and then anticipates the pre-emptive right request to the upcoming intersections. One embodiment of a process according to the present invention for determining whether a distant intersection should be granted with the right of preference in 22
The response to a pre-emptive right request request is shown in Figure 4. The process 70 is initiated by the pre-emptive right request (an external activation). In response to the preemption request, the distant intersection determines (72) whether it is downstream (ie, the vehicle with the right of preference is traveling to the distant intersection along the corridor with the right of way). preference) from the intersection granted with the right of preference. If the distant intersection is not downstream from the intersection with the granted right of preference, then the distant intersection determines (74) whether it is on a side street to the right-of-preference corridor. If not, then the distant intersection ignores the preemption request. If the distant intersection is on a side street, then the distant intersection determines (76) whether it is within a distance and / or threshold time of the right-of-way broker. If not, then the preference request is ignored. If the distant intersection is within the threshold, then the pre-emptive preference request is validated (78). If the distant intersection is downstream of 23
the intersection with the right of preference, then the distant intersection determines (80) whether the distance between the intersection with the right of preference and the distant intersection and / or the estimated time of arrival of the vehicle with the right of preference at the distant intersection they meet a predetermined threshold. The satisfaction of the threshold (s) leads to the validation (78) of the request for the right of early preference. Otherwise, the application for the right of early preference is ignored. The process then attempts to resolve any conflicts that may result from multiple preference requests at the distant intersection. The process determines (82) whether a vehicle with a higher priority is seeking directly to obtain the right of preference to the intersection. If a higher priority vehicle is attempting to directly obtain the right of preference to the intersection, then the request for the right of early preference is ignored and the request for the right of preference of the highest priority vehicle is respected (84). In a modality, the distant intersection can anticipate the request of right of preference to the next intersections. If the right of advance preference request has the highest priority, then the distant intersection respects (86) the 24
request of right of advance preference and advance the request of right of preference to the next intersections. The process can also be initiated by an application with direct preference right (a local activation) provided from a vehicle approaching the distant intersection. The distant intersection responds to the direct preference right request by the determination (88) that if a preemption right request is commonly active at the distant intersection. If a preemption right request is not active, then the distant intersection respects the direct preference right request (90). When a preemptive right request is active, then the distant intersection resolves the conflicting preference right requests in the manner described above (see description in relation to 82-86). Turning now to Figure 5, the manner in which the system responds to a single preference request is illustrated schematically. The vehicle with the right of preference transmits an application for a right of preference that can be received within a limited interval 102 of the vehicle with the right of preference. The intersections 104 within this limited range are 25
granted with the right of preference directly by the vehicle with the right of preference (unless there is an application for a right of preference in conflict). These intersections anticipate the preemption request (the preemption of the preemption request is indicated by a first set of arrows 106). Pre-emptive preference requests are received at the upcoming intersections 108, which are then granted with the right of preference provided that the necessary preemption requirements are met. These intersections anticipate preemption requests (the advance of the preemption request for the next intersections is indicated by a second set of arrows 110). The process is repeated until the intersections 112 receiving the preemption requests no longer satisfy the preemption requirements. Another embodiment of a traffic signal controller according to the present invention is shown in Figure 6. The traffic signal controller 30 'is similar to the traffic signal controller 30 shown in Figure 2 with the exception that the traffic signal controller does not include a right-of-preference device. The traffic signal controller includes a 26
long distance preference module 36 'directly connected to the right of preference entries of a controller 32' of the intersection. The long-distance preference right module and the intersection controller can be implemented in the manner described above, but without the necessity of accommodating a right-of-way device. The modality illustrated in Figure 6 can be used to provide preemption capabilities for intersections to which the right of preference can not be granted directly. In such a configuration, the principal intersections may include direct preference-right capabilities and the intermediate intersections may be granted with the right of preference as a result of the anticipated right-of-way awards of the major intersections. An additional embodiment of a traffic signal controller according to the present invention is illustrated in Figure 7. The traffic signal controller 30"is similar to the traffic signal controller 30 'shown in Figure 1 with the exception of that the long-distance preference right module is connected to a wired network via the work network interface 120. In one embodiment, the wired network could be 27
implemented as an Ethernet LAN. In other modes, other wired network protocols may be used. The use of a wired network can simplify the implementation of networks when a directed message route can be used to forward messages between intersections and can prevent a single intersection from receiving multiple messages containing the same request for the right of preference of the networks. next intersections. Other embodiments of the traffic signal controllers according to the present invention, such as the traffic signal controller 30 illustrated in Figure 2 may be connected to a wired network. In addition, the connection to the wired network can be made directly to an intersection controller. In cases where the intersection controller is directly connected to a wired network, the software of the intersection controller can be modified according to the processes described above to implement the necessary advance and to receive the requests for preemptive rights and to resolve conflicts between pre-emptive preference requests and directly received preference requests. An embodiment according to the present invention 28
of a traffic signal controller wherein the software of an intersection controller is modified to implement the processes described above, is illustrated in FIG. 8. The driver 30 '' 'of the traffic signals includes an intersection controller. 122 that is programmed to implement the preemption rights management processes described above. The intersection controller is connected to a right of preference device 34 '' 'and the intersection controller is programmed in accordance with the present invention to resolve conflicts between requests for advance entry rights and entry rights direct The intersection controller is directly connected to a transceiver 42 '' ', which is similar to the transceiver 42 described above with reference to Figure 3. The intersection controller can use the transceiver to anticipate and receive requests for the right of preference. A mode of a traffic signal controller that includes a programmed intersection controller to handle preemption rights requests and resolve conflicting requests that are connected to distant intersections via a wired network as illustrated in Figure 9. The controller 30"'' of the traffic signals includes a 29
intersection controller 122 'which is connected to a right-of-preference device 34' '' 'and an interface 120' of the network. The driver of the intersection is similar to the driver of the intersection 120 illustrated in Figure 8, however, the driver of the intersection communicates with the distant intersections by means of a network interface, which is similar to the interface of the intersection. the network shown as 120 in Figure 7. Pre-emptive requests can be anticipated and received by the network interface. Although the previous modalities are described as typical, it could be understood that variations, substitutions and further modifications to the system can be made, as described, without departing from the scope of the invention. For example, any number of vehicle estimation techniques can be used and any number of different devices can be used to implement the processes described above and variations of these processes will be considered within the scope of the invention. In addition, any variety of different methods of communicating information between intersections may be used for pre-emptive preference requests. In addition, the traffic signal controllers according to the structures and processes of the present invention can resolve the
conflicts between more than two requests. of preemptive rights that include conflicts that result from multiple advance pre-emptive requests. Accordingly, the scope of the invention should be determined not by the illustrated modes, but by the appended claims and their equivalents. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.