Traffic management at facilities with aisles

Abstract

Facility marking modules (FMM) and methods and systems of using the same. Sets of FMMs are configured and deployed in a given facility, such as a facility configured with very narrow aisles (VNA) to enable alerts between vehicles in danger of colliding in the same aisle of the facility while preventing nuisance alerts between vehicles that are in close proximity but in different aisles such that the danger of colliding is minimal.

Description

TRAFFIC MANAGEMENT AT FACILITIES WITH AISLESCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 618,424, filed on 08 January 2024, the disclosure of which is hereby incorporated by reference in its entirety.FIELD OF THE DISCLOSURE

[0002] This disclosure relates to vehicular and pedestrian safety, traffic control and tracking at facilities with aisles.BACKGROUND

[0003] A variety of concepts have been conceived and tried that provide continuous tracking of moving vehicles and personnel throughout a facility in order to avoid workplace accidents, e.g., collisions with machinery, vehicles, and workers.Many of these safety and tracking systems are centralized and attempt to accomplish all of the interpretations of movements and calculations required to provide a safe working environment and track all of the physical and spatial information. There are many practical problems with these centralized approaches that limit their effectiveness. For example, the centralized approaches require placing the geometry of the facility into a centralized computer system and this geometry must be kept current, a job that is not always easy with frequent shifting locations of products and even parts of the facilities being moved from time to time. And, every item of interest, every vehicle, every person, every object that is relocated must be known and fed into the centralized system. An even more burdensome task is the making of judgements in advance about how to accurately interpret the changes in physical relationships of all these items, while trying to be certain that a safety related consideration is not overlooked or misunderstood. In addition, if there is a failure of the centralized safety and tracking system, then there is a total failure at the work site and all work must stop until the issues are addressed.

[0004] Many ideas have been considered for workplace safety and tracking and some have been successfully implemented. However, experience has shown that eachdeveloped idea tends to be effective to solve some specific problems or do specific jobs but tend to be ineffective or impractical to implement for solving other problems or doing other jobs. Attempts to combine many differing ideas into a composite system tend to be burdensome since each new development tends to require its own resources and support. For example, radio frequency identification systems, such as radio frequency identification (RFID) have been used to provide location awareness of hazardous environments. However, RFID technology cannot precisely be used to identify safety boundaries within an industrial or commercial environment because the RFID waves are too easily reflected by an environment typically filled with industrial equipment, for example, racks, trucks, loading equipment, and inventory, leading to multiple propagation paths and errors. As such, RFID is not sufficient accurate for precise tracking and for providing safety information.

[0005] U.S. Patent No. 5,939,986, incorporated herein by reference in its entirety, disclosed the use of closed-loop, low frequency, magnetic fields to allow mining machines in underground mines to detect pedestrians and to warn both the pedestrians and the operators when they are in close proximity. Since then, other ideas have been disclosed that expanded and improved upon this idea for use in most types of industrial environments, and these ideas have been successfully implemented in new ways, that avert accidents and provide useful data about the equipment operations. These advances are described in detail in numerous Frederick patents, that are referenced in this disclosure.

[0006] Various solutions have been successfully implemented allowing moving equipment to detect and communicate with other moving equipment in order to avoid collisions. These have been effective in open areas along with blind-comer intersections within standard racking configurations. When in racking systems, particularly with very narrow aisles, there is a potential for collision between vehicles (e.g., pick trucks, or pick and place trucks) that may be lifted, along with the operator up to, e.g., 40 feet in the air, presenting visibility challenges and danger from collisions with other vehicles. A challenge exists when the storage racks of a facility have little separation between sets, commonly referred to as a very narrow aisle (VNA) configuration. Due to the magnetic fields’ ability to penetrate obstruction, this creates a challenge of providing adequate alert range in the same aisle while at the same time eliminating a nuisance alert in an adjacent or otherwise nearby aisle. International PCTPatent Application Publication No. WO2022 / 174111, and U.S. Patent Nos. 10,591,627, 11,221,428, and 11,726,226, the contents of all of which are incorporated herein by reference in their entirety, address this concern in VNA configurations by utilizing advanced algorithms on magnetic field vectors.

[0007] However, there remains a need for a solution that does not require vehicle state information such as speed and direction in order to allow for implementation among a diverse fleet of equipment.SUMMARY

[0008] In general terms, the present disclosure is directed to a system (e.g., a vehicular control system) configured to detect when two pieces of equipment (e.g., two vehicles) are in the same aisle of a facility and when they are in adjacent aisles of the facility. When detected that the two pieces of equipment are in the same aisle, the system is configured to issue an alert or stop command to at least one of the pieces of equipment to avoid a collision. When detected that the two pieces of equipment are in adjacent aisles the system is configured so as not to issue any alert or stop command because there is no immediate risk of collision.

[0009] A system according to the present disclosure can include one or more facility marking modules (FMM). Each FMM can be fixed in place within the facility at or near a point of interest (POI), such as near the end of an aisle.

[0010] Each FMM of the system is configured to detect and process low frequency magnetic fields transmitted by a proximity detection system (PDS) of a moving object (e.g., a vehicle) positioned in the facility when the PDS is within a predefined distance of the FMM.

[0011] According to some examples, upon detection of such a magnetic field, the FMM is configured to generate and transmit an appropriate response signal to the PDS and / or to another system of the vehicle. The response signal can include information about the FMM (e.g., an identification of the aisle with which the FMM is associated).

[0012] According to aspects of the present disclosure, the FMMs hereby disclosed may be powered by low voltage, low current, power supplies provided by the facility or may be battery powered, using hibernation capabilities that will be described.

[0013] According to aspects of the present disclosure, a system includes a sufficient number of FMM’s (e.g., two, four, eight, or more FMM’s) to identify anddifferentiate from one another, vehicle presence in at least two adjacent aisles of a facility, A system can be sold as a package of FMM’s to be associated with a predefined number of aisles of a facility,

[0014] Aspects of the present disclosure relate to a traffic management system for a facility with aisles. Further aspects of the present disclosure relate to one or more methods that can be performed by such a system. Further aspects of the present disclosure relate to non-transitory computer-readable storage having stored thereon instructions for causing one or more processors to perform functions of such a system.

[0015] According to certain specific aspects, the present disclosure is directed to a traffic management system, including: a first facility marker module (FMM) associated with a first aisle of a plurality of aisles, the plurality of aisles being configured for vehicular traffic to travel along the plurality of aisles; and a second FMM associated with a second aisle of the plurality of aisles, wherein the first FMM is configured to transmit a signal including a first aisle identifier identifying the first aisle to a first vehicle only when the first vehicle is positioned in the first aisle; and wherein the second FMM is configured to transmit a signal including a second aisle identifier identifying the second aisle to the first vehicle only when the first vehicle is positioned in the second aisle.

[0016] According to further specific aspects, the present disclosure is directed to a traffic management system configured for a facility having a plurality of aisles and a plurality of vehicles, including: a plurality of facility marker modules (FMMs) mounted to different aisles of the plurality of aisles, each FMM including a tuned circuit, a processor and a UHF transceiver, each FMM being configured to transmit signals using the processor and the UHF transceiver in response to receiving, by the tuned circuit, a pulse of a low frequency magnetic field; and a plurality of proximity detection systems (PDS’s) mounted to different vehicles of the plurality of vehicles, wherein the FMMs and the PDS’s are configured to operate together to: (i) detect at a first time that a first vehicle and a second vehicle of the plurality of vehicles are located in the same aisle of the plurality of aisles; (ii) detect at a second time that the first vehicle and the second vehicle are in different aisles, respectively, of the plurality of aisles, wherein at the second time the first vehicle and the second vehicle are in closer physical proximity to each other than at the first time

[0017] According to further specific aspects, the present disclosure is directed to a proximity detection system of a vehicle, including: a radio frequency transceiver; a magnetic field generator; at least one processor; and non-transitory computer-readable storage having stored thereon instructions which, when executed by the at least one processor, cause the proximity detection system to: generate, with the magnetic field generator, a magnetic field pulse that can be received by a facility marker module (FMM); and receive, via the radio frequency transceiver, from the FMM and in response to the FMM receiving the magnetic field pulse, an aisle identifier indicating which aisle of a plurality of aisles the vehicle is positioned in.

[0018] According to further specific aspects, the present disclosure is directed to facility marker module (FMM) configured for a facility having a plurality of aisles and a plurality of vehicles, comprising: a tuned circuit; a processor; and a UHF transceiver, the FMM being configured to transmit signals using the processor and the UHF transceiver in response to receiving, by the tuned circuit, a pulse of a low frequency magnetic field, the signals including an aisle identifier that uniquely identifies one aisle of the plurality of aisles.

[0019] The foregoing aspects are not limiting. Additional aspects of the present disclosure are described below.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a schematic representation of an example facility with vehicles and aisles, including a traffic management system according to an embodiment of the present disclosure.

[0021] FIG. 2 is a schematic representation of an example facility with vehicles and aisles, including a traffic management system according to a further embodiment of the present disclosure.

[0022] FIG. 3 is a schematic representation of a communications protocol between two vehicles using the traffic management system of FIG. 1.

[0023] FIG. 4 is a schematic representation of a vehicle that can use the traffic management system of FIG. 1 and of FIG. 2, the vehicle including an interface between a proximity detection system (PDS) of the vehicle and a controller of the vehicle.

[0024] FIG. 5 is a schematic representation of components of the PDS of the vehicle of FIG. 4.

[0025] FIG. 6 is a schematic representation of an embodiment of a facility marker module of the traffic management system of FIG. 1 and of FIG. 2.

[0026] FIG. 7 is a schematic representation of an example facility with aisles, including a traffic management system according to a further embodiment of the present disclosure.

[0027] FIG. 8 is a schematic representation of an example facility with aisles, including a traffic management system according to a further embodiment of the present disclosure.DETAILED DESCRIPTION OF THE INVENTION

[0028] Like numbers refer to like parts throughout the several drawings.

[0029] VNA-configured facilities (also referred to herein as VNA-configured workplaces), such as warehouses, distribution centers, and the like, are often equipped with traffic management systems for preventing or minimizing collisions between vehicles (e.g., forklifts, pick and place trucks, other trucks and other vehicles moving around on the floor of the facility).

[0030] Solutions exist for such traffic management systems to differentiate between two vehicles that are in close proximity but in different aisles (and therefore pose no risk of collision) and two vehicles that are in close proximity in the same aisle (and therefore do pose a risk of collision). However, existing solutions have drawbacks. For example, existing solutions may require detailed real-time dynamic information for each vehicle (such as speed and direction of each vehicle) to determine which aisle each vehicle is in relative to another.

[0031] An example of an aisle as used herein is a pick aisle that includes racks with different levels from and to which vehicles (e.g., fork trucks) pick and place objects (e.g., boxes, other inventory).

[0032] Another existing solution is to mount LIDAR transmitters and receivers on vehicles. However, such systems cannot distinguish between other vehicles, which pose a collision threat and, e.g., stationary objects such as a box in the aisle, which do not. Such systems are also prone to generating false alarms due to interference from objects not in the pathway of the vehicle, such as the racks themselves, as LIDAR bounces off such objects. Such systems are also often only mounted at one end of the vehicle anddo not detect objects that could potentially result in collision that are at the opposite end of the vehicle.

[0033] Systems of the present disclosure use facility market modules (FMMs) to alleviate one or more of these drawbacks.

[0034] International PCT Patent Application No. PCT / US2023 / 071612, the content of which is incorporated by reference in its entirety, describes the use of facility marker modules to identify points of interest (POIs) throughout a facility, including using FMMs to mark each very narrow aisle in a warehouse.

[0035] According to the present disclosure, systems of FMMs are used to allow tracking of the vehicles in aisles without communications or additional inputs from the vehicles, by utilizing existing proximity detection systems (PDS) of the vehicles and long-life battery powered FMMs positioned in different aisles and communicating in a precisely timed manner on multiple RF frequencies. The communication protocol maintains adequate bandwidth to handle a densely populated warehouse with many pieces of mobile equipment.

[0036] A typical PDS has the ability to collect and log data from all proximity interactions. The FMMs are used to identify points of interest which is also relevant information stored in the PDS system. There may be a need for this information to be combined and communicated to the cloud for further reporting via a cellular data relay. This information can include reporting on policy violations where vehicles violated the separation required in VNA configured facilities, and in which aisle at what time it occurred. With strategic placement of FMMs in a facility in accordance with principles of the present disclosure, and using data science, machine learning, and / or other artificial intelligence (Al) tools, it is possible to provide concise and easy to understand reporting of these interactions to applicable management on a predefined or event- driven basis.

[0037] Advances in available ultra high frequency (UHF) radios allows for quick configuration at multiple radio frequencies and communication at high data rates required to send necessary information between devices. This information can include aisle location and other truck specific information. This enables the system architecture to support the load of many vehicles along with sending necessary information. Concurrency is also used to identify the vehicle generating the magnetic field by thevehicle receiving such that the receiving truck can determine if they are in the same aisle location, and subsequently signal the vehicle / operator.

[0038] Low frequency magnetic fields have been used to produce safety zones, safety markers, warnings, and automatic actions that protect personnel from being hit by mobile machines. This technology has been proven effective for providing proximity detection systems (PDS) and collision avoidance systems (CAS) (PDS / CAS) in many industrial environments. For purposes of this disclosure, a PDS system can be a CAS system in some cases. The high reliability and precision of these low frequency magnetic field systems has led to a variety of system configurations and devices that protect pedestrians, prevent collisions between vehicles and / or machines, and prevent collisions with facility items. Examples of these devices are disclosed in U.S. patents 7,420,471 (the ‘471 patent), 8,169,335 (the ‘335 patent), 8,552,882 (the ‘882 patent)8,232,888 (the ‘888 patent), 8,446,277 (the ‘277 patent), 8,847,780 (the ‘780 patent),8,710,979 (the ‘979 patent), 8,810,390 (the ‘390 patent), 9,081,046 (the ‘046 patent),9,280,885 (the ‘885 patent), 9,822,927 (the ‘927 patent), 10,591,627 (the ‘627 patent),11,221,428 (the ‘428 patent), and 11,726,226 (the ‘226 patent), International PCT application publication number WO2021 / 194904 (the ‘904 publication), International PCT application publication number WO2022 / 174111 (the ‘111 publication) and International PCT Patent Application No. PCT / US2023 / 071612 (the ‘612 application), which patents, publications, and applications are herein referred to collectively as the “Frederick patents,” the disclosures of which are incorporated herein by reference in their entireties.

[0039] The Frederick patents have been used successfully on, for example, fork trucks, loaders, top picks, floor sweepers, tractors, cranes, and other types of machinery. The systems of the present disclosure can be applied to these types of vehicles and others. The Frederick patents describe the useful properties of low frequency magnetic fields that allow for precise, effective proximity detection, even when the source and the sensing device are separated by a wide range of materials and objects. Non-metallic materials essentially have little effect on these fields and even metal objects between the source and detection do not have a significant effect. Effects from multi-path propagation is also avoided. The location of magnetic field generators and detectors are not constrained in the same way that optical devices, like cameras, are, which is important in typical industrial settings line of site is not always available.Line of sight is not required for disclosed basic PDS functionality, as is explained in the mentioned Frederick patents. Being able to not rely on line of sight is also beneficial to FMMs, tracking, and reporting.

[0040] The presently described FMMs and associated systems work with a PDS system that is fundamentally autonomous, i.e., decentralized. Because the FMMs and associated systems are compatible with, and supportive to, a decentralized architecture that already has proven powerful capabilities, the sum of this disclosure and the proven architecture not only provides valuable new capabilities, but also broadens and further equips the PDS architecture with additional decentralized capabilities.

[0041] As just one example, the ‘627 patent describes how low frequency fields can also be used to determine whether a fork truck is in the same aisle as another truck within a metal rack system or is instead in an adjacent aisle. This technique allows for the use of magnetic fields while minimizing nuisance alarms and disrupting activities in adjacent aisles. With the continual advancement in high density storage technology, such as very narrow aisle (VNA) racks, the importance of providing greater safety in these modem storage facilities grows continually. For example, order picker fork trucks that transport the operators to heights of 40 feet or more make it very important that there be no contact between trucks and thus, there is room for improved systems for collisions avoidance. More conventional storage rack systems, even with wide aisles, can benefit from improved collision avoidance since a greater amount of interaction between trucks and other trucks and pedestrians may be required.

[0042] In some examples, a FMM according to the present disclosure can be a portable, battery-operated device, having a long life made possible through a hibernation circuit. The hibernation circuit enables the FMM to remain in a hibernated condition until a vehicle, equipped with a pulsed, low frequency, magnetic field, approaches close enough to the FMM for the magnetic field from the vehicle to “wake up” (e.g., activate) the FMM so that it can send a signal containing relevant information to the PDS of the approaching vehicle.

[0043] The information can be transmitted to the PDS of the approaching vehicle by an ultra-high frequency (UHF) transceiver of the FMM, in response to a magnetic pulse from the PDS. After the transfer of information has been completed, in some examples the FMM returns to hibernation until the next vehicle arrives that triggers theFMM out of hibernation. Alternatively, the FMM can be programmed to continue transmitting until the magnetic field from the vehicle no longer reaches the FMM.

[0044] FMMs according to the present disclosure can serve as aisle markers, e.g., markers of very narrow aisles (VNAs). The transmitted signals by the FMMs can cause vehicles to automatically stop at the ends of aisles associated with the FMMs. The FMMs can also track and analyze vehicle entry to, and exit from, POI aisles in facilities, such as distribution centers. As end of aisle markers, FMMs can be configured to allow for special right of way intersection logic with automated enforcement by automated slowing and / or stopping of vehicles at or near the ends of POI aisles.

[0045] Each FMM can include a battery and can include power-saving features (such as a hibernation circuit) to extend or maximize the operating life of the FMM and minimize the labor required to replace or recharge batteries. Facility managers can have a tendency to avoid battery changes. In some examples, the FMM (e.g., the portable, battery-powered FMM) can be configured to generate an alert when the battery’s voltage drops below a minimum predefined threshold, the alert indicating that the battery should be replaced or recharged soon, e.g., within ten days.

[0046] Many types of facilities can benefit from the use of FMMs according to the present disclosure. Non-limiting examples of such facilities include warehouses with dense VNA metal storage racks, manufacturing facilities with storage areas and shipping docks, roadways along which vehicles travel, office areas and workstations that pedestrians walk into and out of, and so forth.

[0047] Autonomous, de-centralized, self-controlled proximity detection as provided by traffic management systems of the present disclosure ensures a high level of protection from collisions, without depending upon information from a centralized system that must continuously be kept updated and functional. The addition of the FMMs described herein alters the operation of PDS systems to make them practical to use within rack systems. Cooperation between the FMMs and the PDS’s as described herein can accommodate special requirements to further improve safety and improve the functionality of these devices.

[0048] According to systems of the present disclosure, magnetic field detection devices in the form of FMMs are placed at and / or near the ends of very narrow aisles,advantageously allowing a vehicle to avoid collisions with other vehicles in the same aisle while also eliminating additional unnecessary alerts with other vehicles.

[0049] The vehicles used in the systems of the present disclosure can be human- operated with a human on the vehicle, autonomously operated without a human on the vehicle and without actively controlling the vehicle, or remotely operated by a human operator not on the vehicle, or any combination of these, or other types, of vehicle operability.

[0050] The traffic management system allows for advanced communications and traffic control decisions to be made by the vehicle entering the aisle with respect to other vehicles in the facility. A FMM positioned in an aisle sends a signal to the PDS of a vehicle only that is within its magnetic field range. In addition, the FMMs are configured to cooperate with reference information generated by other devices, such as a PDS, another FMM, or a facility guidance system, to determine which direction a vehicle is travelling, e.g., into an aisle from a roadway versus into a roadway from an aisle.

[0051] The magnetic field range can be pre-selected and / or adjusted on site to define a detection zone that has a radius (e.g., about 2, feet, about 4 feet, about 6 feet, about 8 feet, about 10 feet) large enough to capture a PDS of a vehicle within the same aisle as the FMM, but not large enough to capture a PDS of a vehicle positioned in the closest other aisle to the FMM. In certain examples, the magnetic field has a radius in a range from about 5 feet to about 50 feet. In certain examples, the magnetic field has a radius in a range from about 6 feet to about 43 feet.

[0052] The signal sent by the FMM includes an identifier (also referred to as an identification or ID) of the aisle and any other relevant information. The PDS of the vehicle stores the aisle ID learned from the FMM in its memory until the vehicle exits the aisle. In the meantime, the ID is used in communicating with other vehicles.

[0053] In some examples, the aisle ID is used only in communicating with other vehicles in the facility that are in an aisle state as opposed to a non-aisle state, such as roadway state, as will be described in more detail herein.

[0054] According to certain embodiments, a PDS of a given vehicle can operate in two primary states - in an aisle state or in a roadway state, depending on the location of the vehicle at a given moment. For example, if the vehicle is within an aisle, its PDS operates in the aisle state, whereas if the vehicle is within a roadway (e.g., that runsperpendicular to the aisles), its PDS operates in the roadway sate. Switching between the aisle state and the roadway state can occur automatically based on signals received from different FMMs in the facility, such as aisle-marking FMMs and roadway marking FMMs, as well as from other reference information, such as whether a PDS is engaged to a facility guidance system or not engaged to a facility guidance system. Whether a PDS is in an aisle state or a roadway state can also differentiate directional travel of a vehicle. For instance, the aisle state and roadway state can be used to differentiate between a vehicle that is entering an aisle from a roadway (and therefore poses a collision risk to another vehicle already in that aisle and in the aisle state) versus a vehicle that is entering a roadway from an aisle (and therefore poses minimal risk of collision with another vehicle already in that aisle and in the aisle state).

[0055] There are also interface considerations with right of ways and other advanced traffic control that can be made when determining if the other vehicle is in an aisle or in a roadway which leads to appropriate alerts being provided and vehicle / operator actions taken to avoid collisions. In another instance, the type of vehicle entering the aisle may not need to enter this area due to being an improper use for the vehicle. This can be communicated to the vehicle and the vehicle / operator can take the appropriate action.

[0056] A FMM can be used as an aisle identifier in combination with vehicle information such as speed and direction. As a vehicle enters an aisle associated with a given FMM, the vehicle’s PDS acquires a signal that the vehicle is in the aisle and the PDS detects the aisle ID (e.g., an alphanumeric string that uniquely identifies a single aisle of the facility) that is transmitted by the FMM to the PDS. The vehicle (e.g., the vehicle’s PDS) stores the aisle ID in its memory and enters the aisle state.

[0057] When the PDS of the vehicle communicates with a PDS of another vehicle (e.g., another vehicle having a PDS in an aisle state), it sends a concurrent data packet with the aisle ID that it has stored. If both vehicles have the same aisle ID an alerting signal is provided to the vehicle / operator of at least one of the vehicles and, typically at least the vehicle / operator that more recently entered the aisle state.

[0058] If the aisle IDs of the two vehicles do not match, then no alerting signal is provided and thereby a nuisance alert is avoided.

[0059] The PDS can track its location relative to the aisle using speed and direction to determine its location in the aisle, and / or by using the aisle state signal and / orsequence of detection by different FMM’s to determine if it is exiting and should return to roadway state or entering another aisle and should return to the aisle state.

[0060] Another embodiment of a traffic management system of the present disclosure uses sets (or pairs) of FMMs including one as an aisle identifier and the other as a roadway identifier at each end of the aisle that intersects with a roadway to determine entry / exit direction and proper identification of the aisle for collision avoidance. As a vehicle enters an aisle, the PDS detects the roadway marking FMM. As it continues to travel down the aisle the PDS then detects the aisle marking FMM. This sequence causes the PDS to determine that it is entering an aisle from a roadway and therefore enters the aisle state. The vehicle then receives and stores the aisle ID in its memory.

[0061] If the vehicle is exiting the aisle, its PDS detects first the aisle markingFMM and then the roadway marking FMM. This sequence causes the PDS to determine that it is entering a roadway from an aisle and therefore enters the roadway state.

[0062] When the PDS is in the aisle state and communicates with another PDS of another vehicle that is also in the aisle state, it sends a concurrent packet with its stored aisle ID. If both vehicles have the same aisle ID an alerting signal is provided to the vehicle / operator of at least one of the vehicles and, typically at least the vehicle / operator that more recently entered the aisle state. If the aisle IDs do not match, then no alerting signal is provided.

[0063] According to some examples, collision alerts are generated only if two vehicles are both in the same state (e.g., both in the aisle or both in the non-aisle, e.g., roadway state). Determining and setting vehicle states can be performed in a variety of ways, as described herein. For example, determining and setting vehicle states can be performed based on sequence of detection by an aisle marking FMM and a roadway marking FMM. As another example, determining and setting vehicle states can be performed based on whether a PDS is engaged or disengaged from a guidance system. As another example, determining and setting vehicle states can be performed based on other information provided to the PDS from other vehicle systems or devices, such as information on the vehicle’s speed and direction of movement (e.g., is the vehicle changing direction away from a direction of travel associated with a roadway or changing direction away from a direction of travel associated with an aisle). Other possibilities exist.

[0064] Facilities that benefit from this method of aisle identification for collision avoidance are any sized facility that utilizes storage racks that define aisles. Aisle identification can still be useful in standard storage racks configuration. However, it is particularly beneficial in high density very narrow aisle applications such as used in modem distribution centers, where the widths of the aisles are about the same or slightly larger than the corresponding widths of the pick and place vehicles that operate in the facility.

[0065] Multiple versions of the aisle markers may exist beyond the battery- powered FMMs described herein including those that could be facility powered. The advancement in location marking, communication between vehicles, and when, available, the vehicle control interface according to principles of the present disclosure allow for advanced traffic management scenarios including managing and enforcing right of ways for vehicles in aisles and in the roadway while also eliminating nuisance proximity indications.

[0066] FIG. 1 is a schematic representation of an example facility 100 with vehicles and aisles, including a traffic management system according to an embodiment of the present disclosure. The example represented facility includes a VNA racking system within a distribution center where a large variety of parts or products may be stored and subsequently picked for order fulfillment.

[0067] Racks 101 alternate with aisles 102, 120. In this example, the aisles 102 and 120 are adjacent aisles. That is, they are separated by racks 101 with no aisle in between the aisles 102 and 120 that could accommodate a vehicle 107, 108, 109. In this example, there is no aisle in the facility that is closer to the aisle 102 than the aisle 120 and vice versa.

[0068] The racks 101 extend out of the page (perpendicularly to the x-axis and the y-axis) and are configured to store inventory.

[0069] Each aisle 102, 120 has a width WA parallel to the y axis (provided in the drawing as a reference). When a vehicle 107, 108, 109 is positioned in an aisle 102, 120, the vehicle 107, 108, 109 has a corresponding width WV parallel to the y axis. The widths WA and WV are configured such that the width WA is not much larger than (e.g., less than 50 percent larger, less than 40 percent larger, less than 30 percent larger, less than 20 percent larger, less than 10 percent larger, less than 5 percent larger, lessthan 2 percent larger, or less the 1 percent larger than) the width WV, such that the aisles 102, 120 are considered very narrow aisles (VNA).

[0070] A roadway FMM extends past the aisles 102 and 120. The general direction of vehicle traffic in the roadway 150, unless a vehicle is entering an aisle from the roadway 150 or entering the roadway 150 from an aisle, is in one direction or the other along the y-axis, and generally perpendicular to the direction of travel in the aisles 102, 120.

[0071] The traffic management system according to the present disclosure that is used in the facility 100 shown in FIG. 1 includes two different types of FMM - roadway marking FMMs 103 and 105, and aisle marking FMMs 104 and 106.

[0072] In this example, the roadway marking FMMs 103, 105 are placed approximately four feet inside of their aisles 102, 120, respectively (along the x-axis away from the roadway 150). Other positions near the ends of the aisles 102, 120 where the aisles 102, 120 intersect the roadway 150 are also possible.

[0073] The aisle marking FMMs 104 and 106 are placed approximately 12 feet inside of their respective aisles 102, 120.

[0074] The roadway marking FMMs are positioned between the corresponding aisle marking FMMs and the end of the aisles where intersection of the aisles 102, 120 with the roadway 150 occurs.

[0075] Other positions and relative positions of the FMMs 103, 104, 105 and 106 are possible but, in general, the FMMs are arranged such that a vehicle (e.g., a truck) entering an aisle 102, 120 from the roadway 150 will first enter the detection range of a roadway marking FMM 103, 105 and, as the vehicle continues down that aisle 102, 120, it will be subsequently enter the detection range of the corresponding aisle marking FMM 104, 106.

[0076] The FMMs 103, 104, 105 and 106 can be mounted directly to the racks 101 of their respective aisles 102, 120, or to other suitable locations that achieve the functionality of the traffic management system herein. The FMMs 103, 104, 105 and 106 can be relatively small modules, e.g., small enough be to held in one’s hand and mounted easily, (e.g., with adhesive, fasteners, magnets, and the like) to a relatively small mounting location on a rack 101, such as the underside of a shelf, or a surface of a member of a frame (e.g., an upright) of the rack. The low frequency magnetic fieldsutilized by the FMMs can penetrate the material of the racks 101 without interference that would impact performance of the traffic management system.

[0077] The modularity of each FMM 103, 104, 105, 106 allows it to be easily moved to a different location, replaced with another FMM calibrated with the same aisle ID, etc. In some examples, each individual FMM 103, 104, 105, 106 can be independently programmable or adjusted, e.g., to set its vehicle detection range based on the distances between the aisles in a given facility in order to achieve the functionality of the traffic management systems disclosed herein. Alternatively, the FMMs can be pre-set before installation. Each FMM 103, 104, 105, 106 can be battery powered (e.g., with one or more replaceable batteries) with an internal power supply and circuit. Alternatively, one or more of the FMMs can be powered by a central power supply.

[0078] A traffic management system according to the present disclosure can include at least one of the aisle marking FMMs 104, 106. In some examples, a traffic management system according to the present disclosure includes the set of FMMs 103, 104, 105 and 106.

[0079] In some examples, a traffic management system according to the present disclosure includes a set of two each of the FMMs 103, 104, 105 and 106, with one from each pair of FMMs 103 positionable near opposite ends of the aisle 102, one from each pair of FMMs 104 positionable near opposite ends of the aisle 102 further into the aisle than the corresponding FMMs 103, one from each pair of FMMs 105 positionable near opposite ends of the aisle 120, and one from each pair of FMMs 106 positionable near opposite ends of the aisle 120 and further into the aisle than the corresponding FMMs 105. According to this embodiment, both aisle marking FMMs 104 have the same aisle ID transmittable from the FMM 104 to a PDS of a vehicle within its range, and both aisle marking FMMs 106 have the same aisle ID transmittable from the FMM 106 to a PDS of a vehicle within its range and that is different from the aisle ID of the FMMs 104, to thereby differentiate the aisles 102 and 120 from each other when the corresponding aisle marking FMMS 104, 106 identify themselves to vehicles positioned in their respective aisles.

[0080] In some examples, the aisles are blind aisles with only one end open to a roadway. In such example, a traffic management system according to the present disclosure and consistent with the facility 100 of FIG. 1 could include a set of aislemarking FMMs and a set of roadway marking FMMs, where the number of each set is equal to the number of aisles in which the system will be used.

[0081] For example, if the system is being used in a facility with 10 blind aisles open at only one end to a roadway, the system can include 10 aisle marking FMMs programmed with 10 different aisle IDs and 10 roadway marking FMMs.

[0082] As another example, if the system is being used in a facility with 10 aisles that are open at opposite ends to roadways, the system can include 10 pairs of aisle marking FMMs with each pair programmed with a different one of 10 different aisle IDs, and 20 roadway marking FMMs.

[0083] Still referring to FIG. 1, the vehicle 108 is equipped with a PDS 402 and is in the aisle state, the aisle state having been triggered by entering the detection zone of an aisle marking FMM near the opposite end of the aisle 120 (not shown) opposite the direction of the arrow DI . The vehicle 108 is travelling in the direction of the arrow DI within the aisle 120. The PDS 402 of the vehicle 108 has stored an ID identifying the aisle 120 that the vehicle 108 is traveling in. That ID was provided to the PDS 402 of the vehicle 108 when the vehicle 108 entered the detection zone of the aisle marking FMM near the opposite end of the aisle (not shown) and provided by that aisle marking FMM, at which point the PDS 402 of the vehicle 108 also switched to the aisle state.

[0084] A vehicle 107 enters the adjacent aisle 102. As the vehicle 107 enters the adjacent aisle 102, the roadway marking FMM 103 detects a signal transmitted by the PDS 402 of the vehicle 107. This occurs once the PDS 402 enters the magnetic field detection zone 130 defined by the roadway marking FMM 103. The zone 130 is defined by a range, e.g., a constant radius or variable distance from the roadway marking FMM 103. In this example, the zone 130 is defined by a radius R. Once the roadway marking FMM 103 detects the PDS 402 of the vehicle 107, the roadway marking FMM 103 sends a communication to the PDS 402 of the vehicle 107, causing the PDS 402 of the vehicle 107 to be in a roadway state.

[0085] The vehicle 107 continues down the aisle 102 in a direction opposite the direction DI until the PDS 402 of the vehicle 107 is within the magnetic field detecting zone 130 of the aisle marking FMM 104, defined by a radius R, at which point the FMM 104 transmits a communication to the PDS 402 on the vehicle 107. Because the PDS 402 of the vehicle 107 has been in the roadway state, when that PDS 402 enters the zone 130 of the aisle marking FMM 104, the communication sent to the PDS 402 ofthe vehicle 107 from the FMM 104 triggers that PDS 402 to change to the aisle state. Included in the communication to the PDS 402 of the vehicle 107 from the FMM 104 is an ID of the FMM 104, which uniquely identifies the aisle 102 and differentiates the aisle 102 from IDs of all other aisles in the facility, such as the aisle 120.

[0086] The PDS 402 of the vehicle 107 then stores that aisle ID provided by the FMM 104.

[0087] The PDS’s 402 of the vehicles 107 and 108 communicate with each other according to a communications protocol (an example of which is described in more detail below) and compare their stored aisle IDs. Since the comparison reveals that the aisle IDs stored by memories (e.g., non-transitory computer readable storages) of the two vehicles 107 and 108 are different from each other (e.g., do not match) in that the aisles 102 and 120 have different aisle IDs, as a result neither PDS 402 or any other aspect of either vehicle 107, 108 will be alerted about the location of the vehicle, since, because they are in different aisles, there is low likelihood of collision between the vehicles 107 and 108.

[0088] Still referring to FIG. 1, in another scenario, the vehicle 109 enters the aisle 120 that the vehicle 108 is presently in. As the vehicle 109 enters the aisle 120, the roadway marking FMM 105 detects a signal transmitted by the PDS 402 of the vehicle 109. This occurs once the PDS 402 enters the magnetic field detection zone 130 defined by the roadway marking FMM 105. The zone 130 is defined by a range, e.g., a constant radius or variable distance from the roadway marking FMM 105. In this example, the zone 130 is defined by a radius R. Once the roadway marking FMM 105 detects the PDS 402 of the vehicle 109, the roadway marking FMM 105 sends a communication to the PDS 402 of the vehicle 109, causing the PDS 402 of the vehicle 109 to be in a roadway state.

[0089] The vehicle 109 continues down the aisle 120 in a direction opposite the direction DI (i.e., towards the vehicle 108) until the PDS 402 of the vehicle 109 is within the magnetic field detecting zone 130 of the aisle marking FMM 106 defined by a radius R, at which point the FMM 106 transmits a communication to the PDS 402 on the vehicle 109. Because the PDS 402 of the vehicle 107 has been in the roadway state, when that PDS 402 enters the zone 130 of the aisle marking FMM 106, the communication sent to the PDS 402 of the vehicle 109 from the FMM 106 triggers that PDS 402 to change to the aisle state. Included in the communication to the PDS 402 ofthe vehicle 109 from the FMM 106 is an ID of the FMM 106, which uniquely identifies the aisle 120 and differentiates the aisle 120 from IDs of all other aisles in the facility, such as the aisle 102.

[0090] The PDS 402 of the vehicle 109 then stores that aisle ID provided by the FMM 106.

[0091] The PDS’s 402 of the vehicles 108 and 109 communicate with each other according to a communications protocol (an example of which is described in more detail below) and compare their stored aisle IDs. Since the comparison reveals that the aisle IDs stored by memories (e.g., non-transitory computer readable storages) of the two vehicles 108 and 109 are the same as each other (e.g., do match), as a result at least the PDS 402 of one of the vehicles 108, 109 will be alerted about the location of the other vehicle being in the same aisle, since, because they are in the same aisle, there is sufficient likelihood of collision to warrant an alert.

[0092] For example, since both vehicles 108 and 109 are in the same aisle at least one of the vehicles 108, 109 or their operator automatically can receive a stop alert from that vehicle’s PDS system that one of the vehicles is recorded to have entered the same aisle as the other vehicle.

[0093] Still referring to FIG. 1, in another scenario, the vehicle 108 continues to travel in the direction of the arrow DI along the aisle 120 until the PDS 402 of the vehicle 108 is within the detection range 130 of the roadway marking FMM 105, causing the PDS 402 of the vehicle 108 to automatically transition to the roadway state from the aisle state. Meanwhile, the PDS 402 of the vehicle 109 is also in the roadway state. The PDS’s 402 of the vehicles 108 and 109 communicate with each other. In some examples, the vehicle 109 has right of way in the roadway 150 over the vehicle 108. In such examples, the PDS 402 of the vehicle 109 automatically alerts the vehicle 108 as it exits the aisle, issuing a stop alert for the vehicle and / or operator of the vehicle 108, while, due to the right of way rules, the vehicle 109 can continue travel in the direction D3 along the roadway while the vehicle 108 is signaled to stop.

[0094] The magnetic field detection range 130 of each FMM 103 and 104 is calibrated (e.g., at the facility 100 or by factory settings made to the FMMs 103 and 104) not to extend into an adjacent aisle (e.g., the aisle 120) when the FMMs 103 and 104, respectively, are properly mounted to the rack 101 that defines the aisle 102. Similarly, the magnetic field detection range 130 of each FMM 105 and 106 iscalibrated (e.g., at the facility 100 or by factory settings made to the FMMs 105 and 106) not to extend into an adjacent aisle (e.g., the aisle 102) when the FMMs 105 and 106, respectively, are properly mounted to the rack 101 that defines the aisle 120. Thus, these ranges can be adjusted on the individual FMMs based on the width WA of each aisle in the facility in which the FMMs are to be used, as well as the width WR that defines the distance (parallel to the y-axis) between adjacent aisles in the facility in which the FMMs are to be used.

[0095] FIG. 2 is a schematic representation of an example facility 200 with vehicles and aisles, including a traffic management system according to a further embodiment of the present disclosure.

[0096] FIG. 2 represents a simplified VNA racking system within a distribution center where a large variety of parts or products may be stored and subsequently picked for order fulfillment. Racks 201, vehicles 206, 207, 208, and roadway 250 are configured and equipped similarly to the racks 101, vehicles 107, 108 and 109 and roadway 250, respectively of FIG. 1, with e.g., similar actual and / or relative widths of the aisles, racks between aisles, and vehicles.

[0097] In the example in FIG. 2, the facility 200 is also equipped with a guidance system to maintain vehicle travel in a straight line within an aisle. The guidance system is represented by guide paths 210 extending down the center of each aisle 202, 220. The guidance system can include, e.g., laser or other signal-operated transmitter / receiver or the like positioned on a bottom of each truck that bounces signals off the floor or off a guide path and is configured to recognize reflection off the guide paths 210 as compared with reflection of another portion of the floor of the facility. In this or a like manner, the guidance system can monitor deviation of a vehicle from a guide path 210 when the vehicle is in an aisle and automatically generate control signals to steer the vehicle back into alignment with the guide path 210 or to alert the vehicle operator to maneuver the vehicle back into alignment with the guide path 210 when a deviation is detected. In some examples, the PDS of each vehicle 206, 207, 208 is equipped with a transmitter / receiver configured to operate with the guidance system.

[0098] The traffic management system installed in the facility 200, unlike that installed in the facility 100, does not include any roadway marking FMMs. Instead, the traffic management system installed in the facility 200 includes only aisle marking FMMs, with one aisle marking FMM positioned near each end of each aisle (one end ofeach aisle and its corresponding FMM are not shown in FIG. 2) in the case of a aisles that are open at both opposite ends.

[0099] In this example, the aisle marking FMMs 204, 205 are positioned approximately four feet inside of the corresponding aisle, 202, 220.

[0100] The vehicle 207 is equipped with a PDS that is in the aisle state. The vehicle 207 is positioned in the aisle 220. The PDS of the vehicle 207 has already stored the aisle ID corresponding uniquely to the aisle 220 from an aisle marking FMM associated with the aisle 220.

[0101] In one scenario according to FIG. 2, the vehicle 206 enters the aisle 202, which is adjacent to the aisle 220. When the PDS of the vehicle 206 is within the magnetic field detection range of the FMM 204, the FMM 204 automatically sends a communication to the PDS of the vehicle 206, which includes the aisle ID associated with the FMM 204. The PDS of the vehicle 206 stores the aisle ID. The detection ranges of the FMMs 204, 205 can be set and adjusted in the same manner(s) as described with respect to FMMs of FIG. 1.

[0102] Then, once the vehicle 206 also has its guidance system engaged to the guide path 210 of the aisle 202, the PDS of the vehicle 206 changes from the roadway mode to the aisle mode automatically. That is, the PDS of the vehicle 206 (and each of the vehicles) is configured to switch to aisle mode from roadway mode upon the occurrence of both the PDS being detected by and receiving a communication from an aisle marking FMM and the PDS being engaged to the aisle guidance system of the facility, which operates only within the aisles.

[0103] Once the PDS of the vehicle 206 switches to aisle mode, communications between the PDS of the vehicle 206 and the PDS of the vehicle 207 can occur according to a communications protocol, as described later herein. As a result of those communications, the aisle ID stored by the PDS of the vehicle 206 is compared against the aisle ID stored by the PDS of the vehicle 207. Since the comparison reveals that the aisle IDs stored by memories (e.g., non-transitory computer readable storages) of the two vehicles 206 and 207 are different from each other (e.g., do not match) in that the aisles 202 and 220 have different aisle IDs, as a result neither PDS or any other aspect of either vehicle 206, 207 will be alerted about the location of the vehicle, since, because they are in different aisles, there is low likelihood of collision between the vehicles 206 and 207.

[0104] Still referring to FIG. 2, in another scenario, the vehicle 208 enters the aisle 220 that the vehicle 207 is presently in. As the vehicle 208 enters the aisle 220, the aisle marking FMM 205 detects a signal transmitted by the PDS of the vehicle 208. This occurs once the PDS enters the magnetic field detection zone defined by the FMM 205 and the FMM sends the aisle ID for the aisle 220 to the PDS of the vehicle 208. Once the vehicle 208 then engages into the guidance system on the guide path 210 of the aisle 220, the PDS of the vehicle 208 changes to the aisle state, causing communications according to a communication protocol described herein between the PDS of the vehicle 208 and the PDS of the vehicle 208.

[0105] As a result of those communications, the aisle ID stored by the PDS of the vehicle 208 is compared against the aisle ID stored by the PDS of the vehicle 207. Since the comparison reveals that the aisle IDs stored by memories (e.g., non-transitory computer readable storages) of the two vehicles 208 and 207 are the same as each other (e.g., do match) in that the two vehicles are in the same aisle, as a result at least the PDS of one of the vehicles 207, 208 will be alerted about the location of the other vehicle being in the same aisle, since, because they are in the same aisle, there is sufficient likelihood of collision to warrant an alert.

[0106] For example, since both vehicles 207 and 208 are in the same aisle at least one of the vehicles 207, 208 or their operator automatically can receive a stop alert from that vehicle’s PDS system when one of the vehicle’s is recorded to have entered the same aisle as the other vehicle.

[0107] Still referring to FIG. 2, in another scenario, the vehicle 207 continues to travel along the aisle 220 towards the roadway 250 until the guidance system disengages from the PDS of the vehicle 207 (e.g., the PDS no longer receives the engaged wire guidance signal), causing the vehicle 207 to automatically transition from the aisle state to the roadway state. Meanwhile, the PDS of the vehicle 208 is also in the roadway state. Because the PDS’s of the vehicles 207 and 208 are both in the roadway state, they can communicate with each other. In some examples, the vehicle 208 has right of way in the roadway 250 over the vehicle 208. hi such examples, the PDS of the vehicle 208 automatically alerts the vehicle 207 as it exits the aisle 220, issuing a stop alert for the vehicle and / or operator of the vehicle 207, while, due to the right of way rules, the vehicle 208 can continue to travel along the roadway 250 while the vehicle 207 is signaled to stop.

[0108] In some examples, the aisles are blind aisles with only one end open to a roadway. In such example, a traffic management system according to the present disclosure and consistent with the facility 200 of FIG. 2 can include a set of aisle marking FMMs where the number in the set is equal to the number of aisles in which the system will be used.

[0109] For example, if the system is being used in a facility with 10 blind aisles open at only one end to a roadway, the system can include 10 aisle marking FMMs programmed with 10 different aisle IDs.

[0110] As another example, if the system is being used in a facility with 10 aisles that are open at opposite ends to roadways, the system can include 10 pairs of aisle marking FMMs with each pair programmed with a different one of 10 different aisle IDs.

[0111] FIG. 3 is a schematic representation of a communications protocol 300 between two vehicles 301 and 302 using the traffic management system of FIG. 1. The two vehicles 301 and 302 can correspond to any of the vehicles shown and described herein. The aisle marking FMM 350 can correspond to any of the aisle marking FMM’s of FIG. 1. The roadway marking FMM 352 can correspond to any of the roadway marking FMM’s of FIG. 1. The communications take place between the respective PDS’s of the two vehicles, and between the FMM’s and at least one of the PDS’s.

[0112] The vehicles 301 and 302 represented in FIG. 3 are in sufficiently close proximity that their PDS’s detect magnetic field pings (or pulses) generated by the PDS of the other vehicle. The magnetic field pings generated by the PDS’s have limited range. If the PDS’s of the two vehicles are outside of this range (e.g., greater than: 50 feet apart, 40 feet apart, 30 feet apart, 20 feet, 10 feet apart) in proximity to each other, the pings are not received or are too weak in magnitude to be acknowledged, the vehicles are considered to be at a safe distance from each other (even if in the same aisle toward opposite ends), and the remainder of the communications protocol does not ensue.

[0113] The PDS’s of the vehicles in a facility, such as the facility 100 of FIG. 1, continue to transmit magnetic field pings (e.g., at set intervals) until an echo signal is received from another vehicle, which indicates that another vehicle is sufficiently close by that there is a potential risk of collision, and therefore, the communications protocol as outlined in FIG. 3 proceeds.

[0114] Still referring to FIG. 3, example frequencies for both radio and magnetic signals are provided below. These examples are not limiting. Other frequencies are possible. Time advances in the direction of the arrows 310 and 312. However, relative durations of time between signals shown in FIG. 3 are not necessarily to scale within the figure.

[0115] The protocol in this example is initiated by the PDS (such as a PDS 402) of the vehicle 301 sending a data packet 303 at 900 megahertz (MHz) using a UHF radio that is received by a radio receiver of the PDS of the vehicle 302. The data packet 303 includes the state of the vehicle 301 (whether it is in aisle state or roadway state). If the vehicle 301 is in the aisle state, then the data packet 303 also includes the aisle ID (or identifier) uniquely indicating in which aisle the vehicle 301 is positioned. The aisle can have been stored by the PDS of the vehicle 301 as described herein.

[0116] In addition to the data packet 303, the PDS of the vehicle 301 also sends a magnetic field ping 304 at 73 kilohertz (KHz) generated by a magnetic field generator of the PDS of the vehicle 301 that is received (if the vehicles 301 and 302 are within sufficiently close proximity) by a magnetic field detector of the PDS of the vehicle 302.

[0117] In the example shown, the ping 304 is sent after the data packet 303. In other examples, the ping 304 is sent before the data packet 303. In still other examples, the ping 304 and the data packet 303 are sent concurrently. The PDS of the vehicle 302 is configured to pay attention to the data packet 303 and thereby learn the state (roadway or aisle) of the vehicle 301 and, if applicable, which aisle it in, provided that the PDS of the vehicle 302 it has received the corresponding ping 304 within a predefined period of time from receiving the data packet 303.

[0118] Once the PDS of the vehicle 302 receives the data packet 303 and the magnetic ping 304, if the data packet 303 indicates that the vehicle 301 is in the aisle state and the vehicle 302 is also in the aisle state, the PDS of the vehicle 302 compares the aisle ID to its own stored aisle ID. If, in this scenario the aisle ID’s match or, in a different scenario, the data packet 303 indicates that the vehicle 301 is in the roadway, then the PDS of the vehicle 302 sends a 900 MHz UHF echo signal 305 during a predefined echo window, or period of time 306, and then returns to listening on the UHF radio of the PDS of the vehicle 302 until it initiates the same sequence initiated by the vehicle 301, or receives another packet or ping. In the meantime, vehicle control actions, such as stop commands or collision alerts, are generated if appropriate basedon the states of the two vehicles and, if they are both in the same state, whether they are in or entering the same aisle or in or entering the same roadway, as determined by the signals 303, 304 and 305 and as described in more detail herein.

[0119] Following the echo window 306, the vehicle 301 listens for a 900 MHz UHF aisle marker data packet 308 from an aisle marking FMM 350 during the subsequent period of time, or window 307. If an aisle marker data packet is received, the PDS 301 changes its state to the aisle state if it was previously in the roadway state, and stores the aisle ID (or identifier) of the aisle marker data packet 308 if different from an aisle marker ID presently stored by the vehicle 301.

[0120] The foregoing communications protocol including signals 303, 304, 305 and 308 can be performed by various traffic management systems described herein, such as the systems of FIGS. 1 and 2.

[0121] In some examples, such as to implement the system of FIG. 1, which includes roadway marking FMMs, the protocol 300 includes, following the window 307, a subsequent period of time or window 309 during which the PDS of the vehicle 301 listens for a roadway marker packet 314 at the appropriate UHF frequencies from a roadway marking FMM 352. The data payload of a roadway marker data packet 314 causes the PDS of the vehicle 301 to enter the roadway state if it was previously in the aisle state. In some examples, the data payload of the roadway marker data packet 314 includes a roadway identifier that identifies the roadway the vehicle is in or is entering.

[0122] Following the window 307 or, following the window 309 in embodiments of the system that include roadway marking FMMs, the vehicle 301 returns to listening on the UHF radio until it initiates the same sequence again (beginning from the magnetic ping 304) as shown in FIG. 3, or until the vehicle 301 receives the same sequence from the vehicle 302 or from another vehicle in the facility that is moved into sufficiently close proximity the trigger the sequence of communications shown in FIG.3.

[0123] In some examples, the total amount of time 319 for the entire sequence of signals shown in FIG. 3 is estimated to be between about 8 milliseconds and about 18 milliseconds. Durations that are shorter or longer than this range may also be possible.

[0124] FIG. 4 is a schematic representation of a vehicle 401 that can use the traffic management system of FIG. 1 and of FIG. 2, the vehicle including an interface between a position detection system (PDS) 402 of the vehicle and a controller of thevehicle. The vehicle 401 can correspond to any of the vehicles described and / or shown herein. In this example, the vehicle 401 is a forklift truck.

[0125] The interface of the PDS 402 and vehicle controller 404 is provided via a bi-directional communication protocol 403 such as CAN BUS. This interface allows, for example, for slow and stop commands to be provided to vehicle controller 404 from the PDS 402 in response to receiving a data packet from another vehicle that it is in the same aisle.

[0126] In some examples, the PDS 402 can store information in, and access information from, the controller 404 via the interface 403. Such information can include, e.g., the current aisle ID of the vehicle 401 uniquely reflecting the aisle in which the vehicle 401 is presently located, the speed of the vehicle 401, the direction of movement of the vehicle 401, whether the vehicle 401 is in a roadway state or an aisle state, and the like.

[0127] The controller 404 is configured to generate alerts that are provided to an output device of the vehicle 401 (e.g., a display, a warning light, an audible alarm, a vibration, and the like) that can be seen, heard and / or felt by an operator of the vehicle 401 such that the operator is alerted when they need to stop or slow down in view of the risk of collision with another vehicle in the same aisle. In some examples, the controller 404 can be figured to automatically cause the vehicle 401 to slow down, stop, and / or change direction in response to signals received by the PDS 402 indicating that a collision with another vehicle in the same aisle (or in the same roadway) is possible. Thus, the controller 404 can include one or more processors, one or more output devices, one or more input devices that receive signals from the PDS 402 and other devices of the vehicle (e.g., speedometer, sensors) and non-transitory computer readable storage having stored thereon instructions, that, when executed by the one or more processors, perform one or more of the functions of the controller described herein.

[0128] FIG. 5 is a schematic representation of components of the PDS 402 of vehicle of FIG. 4. PDS’s according to the present disclosure can have more components, fewer components and / or different components from the example components shown in FIG. 5. The PDS 402 can also be considered a device, e.g., a proximity detection device.

[0129] Referring to FIG. 5, the example PDS 402 is configured to be installed on a vehicle, such as any of the vehicles disclosed herein. The PDS 402 includes components configured to perform the functions of the PDS described herein. These components include a radio frequency transmitter 500, a radio frequency receiver 502, a low frequency magnetic field generator 504, a low frequency magnetic field detector 506, one or more processors 510, computer readable storage 512, which can include non-transitory computer readable storage that stores instructions that can be executed by the one or more processors 510, and in certain examples, such as vehicles used with the embodiment of the traffic management system shown inf FIG. 2, a guidance system detector 508.

[0130] The radio frequency transmitter 500, for example, is configured to generate and transmit (also referred to herein as send) UHF signals, such as those described in connection with FIG. 3.

[0131] The radio frequency receiver 502, for example, is configured to receive UHF signals, such as from PDS’s of other vehicles or from FMMs sending signals that change the state of the PDS 402 (e.g., between an aisle state and a roadway state) and / or provide aisle ID information.

[0132] The magnetic field generator 504, for example, is configured to generate the magnetic field pings described above in connection with FIG. 3, as well as the magnetic fields that can be detected by the FMMs when the PDS 402 is in close proximity. The generator 504 can be calibrated to limit the range of the generated pings as described above.

[0133] The magnetic field detector 506, for example, is configured to detect low frequency magnetic fields, such as magnetic field pings generated by other vehicles as described above.

[0134] The guidance system detector 508 is configured to detect external triggers of a guidance system in the facility and, upon detection, engage the vehicle into the guidance system by monitoring the position of the vehicle relative to a guide path and generate signals that can passed to the vehicle controller to maintain the vehicle on the guide path.

[0135] The processor(s) 510, via circuity and / or network interfaces via a network (e.g., a Cloud, the Internet), are configured to receive inputs generated by the components 500, 502, 504, 506, and 508 and, in conjunction with one or more softwaremodules containing computer-readable instructions stored on the storage 512, perform various functions of the PDS described herein, such as storing an aisle ID received in a data packet from a FMM, comparing a stored aisle ID to another aisle ID received from a PDS of another vehicle and ensuing signaling functions, causing the transmitter 500 or the generator 504 to generate and transmit a signal (such as the signals shown in FIG. 3), causing the controller 404 (FIG. 4) to generate an alert or to cause the vehicle to slow down, stop, change direction, or the like, as described herein.

[0136] The computer-readable storage 512 stores computer-readable instructions executable by the processors) 510. The storage 512 can include any of a multitude of different types of memory. In some examples, the aisle IDs are temporarily stored on the storage 510. In other examples, aisle IDs are stored elsewhere, such as on the controller 404 (FIG. 4).

[0137] FIG. 6 is a schematic representation of an embodiment of a facility marker module 600 of the traffic management system of FIG. 1 and of FIG. 2. The example FMM 600 can correspond to any of the aisle marking FMMs and roadway marking FMMs described herein.

[0138] Referring to FIG. 6, the FMM 600 contains a circuit board 610 that supports and includes a capacitor 604, an inductor 605, and a tuned circuit 606 all configured for reception of low-frequency magnetic field signals, such as magnetic field signals (e.g., pulses) generated by the magnetic field generator 504 (FIG. 5) of a PDS 402 that is within the predefined maximum detection range of the FMM 600. When a low frequency magnetic field signal is received (e.g., from a vehicle PDS), it is interpreted by the processor 609. If the signal is valid, the FMM 600 responds (e.g., to the PDS of a vehicle) with a timed UHF transmission via the UHF transceiver 607 and the antenna 608. If the FMM 600 is a roadway marking FMM, for example, the response can include a signal that triggers the PDS to enter roadway mode. If the FMM 600 is an aisle marking FMM, for example, the response can include a signal that triggers the PDS to enter aisle mode and also includes the aisle ID corresponding to the aisle in which the FMM 600 is placed. The frequency of the UHF transceiver may vary.

[0139] The FMM 600 is powered with a battery 603. In some examples, the battery 603 is positioned within a dedicated, modular, hand-holdable housing 630 of the FMM 600. The housing 630 can house all components of the FMM 600 and is configured to be mounted to a structure, such as a rack of a facility. The housing 630can be a plastic enclosure with a removable battery lid 602 for easy replacement of the battery 603, e.g., every two years. Exact construction of the device enclosure may vary. To configure the specific functionality of the FMM 600 as described herein, in some examples a wireless UHF configuration tool 617 can be used. A configuration tool, such as the tool 617 can be used, e.g., to set the aisle identifier for the FMM 600, such that the microprocessor 609 can cause a data packet that includes the aisle identifier for that FMM to be generated and transmitted.

[0140] FIG. 7 is a schematic representation of an example facility 700 with aisles, including a traffic management system according to a further embodiment of the present disclosure.

[0141] The facility 700 includes an arrangement 790 of racks 701, aisles 702, 703 and roadways 750, 760.

[0142] The traffic management system used for the facility 700 is similar to that used for the facility 200 shown in FIG. 2. In FIG. 7, the aisles 702 and 703, which are defined by racks 701, are not blind and extend at their opposite ends to intersect with two different, parallel roadways 750 and 760. As shown, aisle marking FMMs 704 (like other such FMMs described herein) are positioned near the intersection of each aisle 702, 703 with the corresponding roadway 750, 760. A traffic management system such as this installed in a facility such as the facility 700 was described in more detail above.

[0143] FIG. 8 is a schematic representation of an example facility 800 with aisles, including a traffic management system according to a further embodiment of the present disclosure.

[0144] The facility 800 includes the same arrangement 790 of racks, aisles and roadways as the facility 700 of FIG. 7.

[0145] The traffic management system used for the facility 800 is similar to that used for the facility 100 shown in FIG. 1. In FIG. 8, the aisles are not blind and extend at their opposite ends to intersect with two different, parallel roadways. As shown, aisle marking FMMs 804 (like other such aisle marking FMMs described herein) and roadway marking FMMs 806 (like other such roadway marking FMMs described herein) are positioned near the intersection of each aisle with the corresponding roadway, with, for each aisle, the aisle marking FMM’s positioned between the two roadway marking FMMs. A traffic management system such as this installed in a facility such as the facility 800 was described in more detail above.

[0146] Although specific embodiments are described herein, the scope of the technology is not limited to those specific embodiments. Moreover, while different examples and embodiments may be described separately, such embodiments and examples may be combined with one another in implementing the technology described herein. One skilled in the art will recognize other embodiments or improvements that are within the scope and spirit of the present technology. Therefore, the specific structure, acts, or media are disclosed only as illustrative embodiments. The scope of the technology is defined by the following claims and any equivalents therein.

Claims

What is claimed is:

1. A traffic management system, comprising: a first facility marker module (FMM) associated with a first aisle of a plurality of aisles, the plurality of aisles being configured for vehicular traffic to travel along the plurality of aisles; and a second FMM associated with a second aisle of the plurality of aisles, wherein the first FMM is configured to transmit a first signal including a first aisle identifier identifying the first aisle to a first vehicle only when the first vehicle is positioned in the first aisle; and wherein the second FMM is configured to transmit a second signal including a second aisle identifier identifying the second aisle to the first vehicle only when the first vehicle is positioned in the second aisle.

2. The traffic management system of claim 1, further comprising a first proximity detection device (PDS), wherein when the first PDS is mounted to the first vehicle, the first PDS is configured to: receive the first signal including the first aisle identifier when the first vehicle is in the first aisle; store the first aisle identifier; and transmit the first aisle identifier to a second PDS mounted to a second vehicle that is within a predefined range of the first PDS.

3. The traffic management system of claim 2, wherein the second PDS is configured to compare the first aisle identifier to another identifier stored by the second PDS; wherein when the first aisle identifier and the another aisle identifier are the same, at least one of:(i) the first PDS is configured to generate a collision alert signal indicating that the first vehicle and another vehicle are in the same aisle and further configured to transmit the collision alert signal to a controller of the first vehicle; or(ii) the second PDS is configured to generate a collision alert signal indicating that the second vehicle and the another vehicle are in the same aisle and further configured to transmit the collision alert signal to a controller of the second vehicle; and wherein when the first aisle identifier and the another aisle identifier are different, no collision alert signal is generated by either the first PDS or the second PDS.

4. The traffic management system of claim 3, wherein the first aisle identifier and the another aisle identifier are different and the another aisle identifier is the second aisle identifier.

5. The traffic management system of any of claims 1-4, wherein the first signal including the first aisle identifier is a UHF radio signal; and wherein the first FMM is further configured to detect a magnetic field pulse.

6. The traffic management system of any of claims 2-4, further comprising a third FMM associated with the first aisle and positioned closer to an intersection of the first aisle and a roadway running perpendicularly to the first aisle and the second aisle than the first FMM, wherein the first PDS is configured to determine, based on signals received by the first PDS from the first FMM and the third FMM, whether the first vehicle is entering the first aisle from the roadway or entering the roadway from the first aisle.

7. The traffic management system of claim 6, wherein the first PDS determines whether the first vehicle is entering the first aisle from the roadway or entering the roadway from the first aisle based on a sequence in which the first FMM and the third FMM detect the first PDS.

8. The traffic management system of any of claims 6-7, wherein the first FMM is configured to transmit the first signal including the first aisle identifier identifying the first aisle to the first vehicle only when the first vehicle is positioned in the first aisleand when the first PDS determines that the first vehicle is entering the first aisle from the roadway or from another roadway.

9. The traffic management system of any of claims 2-4, wherein the first PDS is configured to engage, and disengage from, a guidance system associated with the first aisle, the guidance system being configured to inhibit the first vehicle from moving away from a guide path within the first aisle when the first PDS is engaged to the guidance system; and wherein the first FMM is configured to transmit the first signal including the first aisle identifier identifying the first aisle to the first vehicle only when the first vehicle is positioned in the first aisle and when the first PDS is engaged to the guidance system.

10. A traffic management system configured for a facility having a plurality of aisles and a plurality of vehicles, comprising: a plurality of facility marker modules (FMMs) mounted to different aisles of the plurality of aisles, each of the plurality of FMMs including a tuned circuit, a processor and a UHF transceiver, each of the plurality of FMMs being configured to transmit signals using the processor and the UHF transceiver in response to receiving, by the tuned circuit, a pulse of a low frequency magnetic field; and a plurality of proximity detection devices (PDS’s) mounted to different vehicles of the plurality of vehicles, wherein the plurality of FMMs and the plurality of PDS’s are configured to operate together to:(i) detect at a first time that a first vehicle and a second vehicle of the plurality of vehicles are located in the same aisle of the plurality of aisles;(ii) detect at a second time that the first vehicle and the second vehicle are in different aisles, respectively, of the plurality of aisles, wherein at the second time the first vehicle and the second vehicle are in closer physical proximity to each other than at the first time.

11. The traffic management system of claim 10, wherein the plurality of FMMs and the plurality of PDS’s are configured to operate together to:(iii) generate, based on the detect at the first time, a collision alert signal and transmit the collision alert signal to a controller of at least one of the first vehicle and the second vehicle; and(iv) not generate, based on the detect at the second time, any collision alert signal for transmission to any controller of any of the first vehicle or the second vehicle.

12. The traffic management system of any of claims 10-11, wherein the plurality of FMMs and the plurality of PDS’s are configured to operate together to:(iii) determine when one of the plurality of vehicles is entering one of the plurality of aisles from a roadway; and(iv) determine when one of the plurality of vehicles is entering the roadway from one of the plurality of aisles.

13. The traffic management system of any of claims 10-12, wherein the PDS’s are configured to engage, and disengage from, guidance systems associated with the plurality of aisles, the guidance systems being configured to inhibit the plurality of vehicles from moving away from guide paths within the plurality of aisles when the PDS’s are engaged to the guidance systems.

14. The traffic management system of claim 13, wherein the plurality of FMMs and the plurality of PDS’s are configured to operate together to perform (i) and (ii) only when the first vehicle and the second vehicle are engaged to at least one of the guidance systems.

15. A proximity detection device of a vehicle, comprising: a radio frequency receiver; a magnetic field generator; at least one processor; and non-transitory computer-readable storage having stored thereon instructions which, when executed by the at least one processor, cause the proximity detection device to:generate, with the magnetic field generator, a magnetic field pulse that can be received by a facility marker module (FMM); and receive, via the radio frequency receiver, from the FMM and in response to the FMM receiving the magnetic field pulse, an aisle identifier indicating which aisle of a plurality of aisles the vehicle is positioned in.

16. The proximity detection device of claim 15, further comprising: a magnetic field detector configured to receive magnetic field pulses generated by another proximity detection device of another vehicle; and a radio frequency transmitter configured to transmit the aisle identifier to the another proximity detection device.

17. The proximity detection device of any of claims 15-16, including further instructions which, when executed by the at least one processor, cause the proximity detection device to store the aisle identifier until the proximity detection device enters a roadway or another aisle.

18. The proximity detection device of any of claims 15-16, including further instructions which, when executed by the at least one processor, cause the proximity detection device to provide a collision alert signal to a controller of the vehicle.

19. The proximity detection device of any of claims 15-18, further comprising a guidance system detector configured to engage, and disengage from, a guidance system associated with an aisle of the plurality of aisles.

20. A facility marker module (FMM) configured for a facility having a plurality of aisles and a plurality of vehicles, comprising: a tuned circuit; a processor; and a UHF transceiver, the FMM being configured to transmit signals using the processor and the UHF transceiver in response to receiving, by the tuned circuit, a pulse of a low frequency magnetic field, the signals including an aisle identifier that uniquely identifies one aisle of the plurality of aisles.

21. A traffic management system, comprising: a proximity detection device (PDS) associated with a vehicle; a first facility marker module (FMM) associated with an aisle of a plurality of aisles, the plurality of aisles being configured for vehicular traffic, including the vehicle, to travel along the plurality of aisles; and a second FMM associated with the aisle and with a roadway running perpendicularly to the plurality of aisles, wherein the PDS is configured to sequentially listen for one of, and then the other of, (i) an aisle marker data packet generated by the first FMM and (ii) a roadway market data packet generated by the second FMM.

22. The traffic management system of claim 21 , wherein the PDS is configured to listen for (i) during a first period of time and then to listen for (ii) during a second period of time, the second period of time beginning at or after when the first period of time ends.

23. The traffic management system of claim 21 , wherein the PDS is configured to listen for (ii) during a first period of time and then to listen for (i) during a second period of time, the second period of time beginning at or after when the first period of time ends.

24. The traffic management system of any of claims 21-23, wherein the PDS is configured to: change to an aisle state based on receipt by the PDS of (i); and change to a roadway state based on receipt by the PDS of (ii).

25. The traffic management system of any of claims 21-24, wherein the PDS is configured to determine a direction of travel of the vehicle based on a sequence in which (i) and (ii) are received by the PDS.

26. The traffic management system of any of claims 21-25, further comprising the vehicle.

27. The traffic management system of any of claims 21-26, wherein the first FMM and the second FMM are mounted to the same rack with the second FMM being positioned closer to the roadway than the first FMM.

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