Patent Application
20200082722
The present invention relates to navigation systems for autonomous vehicles and, more particularly, to a system for improving the capabilities of partially or fully autonomous vehicles by adding dedicated RFID tags and/or a radar reflector to low-electromagnetic-profile objects that the vehicle may encounter while trying to navigate using only its own instrumentation.
A vehicle trying to navigate using its sensors may encounter numerous low-electromagnetic-profile objects such as a bicycle, motorcycle, livestock animals, pets, horses, children, road-side posts, stop-sign, traffic light, policeman, round-about, and the like. Undetected objects and/or misidentification of those object can hamper the vehicle's navigation system and cause very serious safety issues.
Modern vehicles are controlled partially or fully by a control system that gets information of surrounding objects by an array of sensors, e.g., optical, visual, RF-based, etc. Future transportation technologies will rely even more significantly on such sensors to detect the surrounding objects and guide the vehicle safely. However, the information sensed by the vehicle's sensors can be misleading; for example, an object like a soda can produce a radar image far out of proportion to its size, while a plastic road-side post or a child can produce a radar image much smaller than it is. Moreover, relying on information that is received from external networks (cellular, Wi-Fi, Bluetooth, BLE, proprietary, VANET and the like) can cause serious safety issues due to communication speed, accuracy and reliability issues, etc.
Therefore, increasing automation levels requires a system that can accurately sense and analyze complex scenarios so as to correctly respond to multiple potential hazards in real-time. Moreover, fast-moving vehicles require fast, real-time and accurate information.
One of the most prominent issues that autonomous (or semi-autonomous) vehicle technology faces is the inability to detect and react to cyclists (as an example of low-electromagnetic-profile objects) in biking lanes or who share the road with vehicles. Though, cyclists are not the only objects that the vehicles' sensors find difficult to detect. A vehicle encounters many other objects with low-electromagnetic profile; children, motorcycles, pets, horses, pigs, bulls, guardrails (specifically non-metal), pedestrians, traffic-light, road-side signs, roundabout, etc. (and any combination thereof), whereby such low-electromagnetic profile objects are often not detected, or their detection is misidentified—i.e., their perceived electromagnetic profile is different than what is identified. Even visual sensors like cameras or IR sensors can often be misleading when sensing children, for example.
A vehicle trying to navigate by relying solely on information coming from its sensors must have accurate information on all surrounding objects based in at least in part on such object's electromagnetic profile, or more specifically its Radar Cross Section (RCS). This radar reflection/emission is also known as a “radar fingerprint” or “radar signature”. Again, such navigation cannot be flawlessly achieved, however, because some objects have a low electromagnetic profile. On the other hand, if the surrounding objects could identify their “nature” (i.e., who am I? How big I am? my status, etc.) in addition to their accurate, real-time position, the overall effectiveness and safety of the vehicle could be significantly improved. Especially in an urban environment where the density and diversity of objects are very challenging, optimal performance requires reliable, accurate and fast detection methods of all the objects, including those with low-electromagnetic profiles.
Nowadays, five major classes of vehicular sensors provide the lion's share of environment sensory data for vehicle control. Those sensors include:
(1) Short, medium and long-range radars;
(2) Light Detection and Ranging (hereafter LIDAR);
(3) Image sensors (mainly cameras in the infrared and visual bands);
(4) Ultrasound; and
(5) Cameras, and the like and any combination thereof.
Radar-based systems that are typically employed in automotive active safety systems can be subdivided into three major classes:
Failing to detect the surrounding objects affects the decisions the vehicle control unit makes, and the consequences could be dire-particularly if the car is relying on that information to navigate and avoid crashing into them. As an example, a small child standing next to a vehicle can become “invisible” to a radar receiver. Moreover, the growing use of; composite material like carbon-fiber in the structures like frames of bicycles and motorcycles, in addition to the prevalence of plastic-based parts (in roadside signs and vehicles), decreases those objects electromagnetic profile even more. This is because radar-based sensors rely on the reflected, electromagnetic radiation from the object to be detected. The effectiveness of any radar-based system depends on the reflected, electromagnetic radiation. Low-reflected, electromagnetic radiation impairs the effectiveness of any radar-based sensor significantly. This phenomenon is used (but to achieve the opposite effect) by stealth aircraft which are designed to avoid detection using a variety of technologies that reduce reflection/emission of radars.
A variety of methods in use by vehicle radar systems; Long Range Radar (LRR) systems operate in the 77 GHz frequency band (76-81 GHz), the broadband Frequency Modulated Continuous Wave (FMCW) that combines high resolution in range and depth perception, with the detection of objects in a small radar cross-section, automatic emergency braking system (AEBS) and adaptive cruise control (ACC).
Bicycles, as an example, pose a complex detection problem because they are relatively small, fast and heterogenous, unlike a car which is a big block of stuff. A bicycle has significantly less mass (mainly metal) and usually has multiple variations in appearance: i.e., there are more shapes, colors, material compositions, and stuff attached to bicycles. Tests have shown that today's systems spot only 74 percent of bikes vs. 88 percent of the vehicle. Current technology for vehicle control (partially or full-self-driving cars) thus faces an inability to detect and react to cyclists in biking lanes or who share the road with vehicles. Bicycles are much less predictable, nimbler than cars because it's easier for them to make sudden turns or jump out of nowhere. A 2017 study by the IEEE Spectrum found that out of all forms of transportation that autonomous cars interact with, self-driving car technology has the most difficulty detecting bicycles.
As can be seen, there is a need for a system for improving the capabilities of partially or fully autonomous vehicles by adding dedicated RFID tags and/or a radar reflector to low-electromagnetic-profile objects that the vehicle may encounter while trying to navigate using only its own instrumentation. The system and methods of the present invention offer a very low-cost solution through incorporating a reflector and/or RFID to the bicycle, as an example of an object with a low electromagnetic profile. The reflector bounces back the radar signals of the vehicle and the RFID respond to the vehicle RFID reader with information on its identification; “I'm a bicycle”, “my correct position is . . . ”, “my current speed is . . . ”, “my direction is . . . ”, and the like.
While today, an autonomous (semi or full) vehicle relies only on its sensors and their processing power at their control unit for road objects detection and identification, the disclosed systems and methods of the present invention give real-time and accurate information from low-electromagnetic-profile objects it may encounter, in a very reliable manner and at an affordable price. The information is added to the vehicle's existing control system inputs and improves the accuracy and safety of the vehicle's navigation mainly for semi or fully autonomous vehicles.
The system and method of the present invention can be small in size, low cost, weatherproof, immune to cyber-attacks, powerless (passive) and consume very limited power that is needed in active or continuously programmable RFID versions. Its power, if needed, can be supplied by a battery and/or a solar cells panel, wind turbine, or the like, thereby enabling implementation of this technology in remote areas without a connection to the electrical grid. Due to its low cost it is very affordable even for low-cost objects (such as basic road-side plastic warning sign). The system of the present invention (the passive version RFID) is immune to any hacking attacks as its data can't be modified online, unlike many IoT (Internet of Things) devices. Moreover, it is very simple to implement and install and requires very low maintenance if any.
Increasing an object's electromagnetic signature and/or its identification can be subdivided into two basic methods; passive and active. A passive method uses the energy coming from the transmitting device only. In the active devices, the reflected signal is enhanced (amplified), or triggering action that is received by the transmitting device.
In one aspect of the present invention, a method for improving a vehicular navigation control system includes the following: providing a vehicle having a navigation control system; connecting an RFID reader to the vehicle and operatively associated to said navigation control system; and attaching one or more reflectors to at least one object having a low radar cross-section, wherein each reflector increases the radar cross-section; coupling one or more RFID tag to each object, wherein each RFID tag retrievably stores an identification data comprising a nature of said object; and said nature being irrespective of a position of said object, wherein the RFID reader is configured to interrogate every RFID tag within an operable range so that the RFID tag discloses the identification data.
In another aspect of the present invention, a method of creating a vehicular ad-hoc network includes the following: providing a plurality of vehicles incorporating the above-mentioned method; and each navigation control system configured to share the identification data of each object with each vehicle beyond the operable range; a traffic module coupled to each navigation control system, wherein the traffic module comprises a status of traffic regulation in the operable range, and wherein the traffic module is coupled to the identification data of each object.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.
The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
Broadly, an embodiment of the present invention provides a system and methods for improving the performances and safety of vehicles' control systems by increasing the detectability and the information of low-electromagnetic-profile objects, such as road signs, children, and the like, by the vehicle's control-system sensors. The disclosed systems and methods of the present invention includes radar reflectors and RFID tags (passive, active or continuously-programmable) attached to low-electromagnetic-profile objects on one end, and radars, cameras and RFID readers (also known as an interrogator) added to the vehicle and connected to its control system on the other end.
The system includes radar reflectors and RFID tags attached to low-electromagnetic-profile objects and storing in their memory the relevant information about the object. The vehicle is equipped with radars, cameras and one or more RFID interrogators. The low-electromagnetic-profile objects reflect more effectively the radar signals and respond to interrogation by an RFID reader, providing, in real-time, vital information about the characteristics of the low-electromagnetic-profile object, like, nature, position, status, and the like, to the interrogating vehicle control system.
It should be understood that the definition of the following words and terms having the following meanings:
The terms “about” and “essentially” mean±10 percent.
The terms “a” or “an,” as used herein, are defined as one or as more than one. The term “plurality”, as used herein, is defined as two or as more than two. The term “another”, as used herein, is defined as at least a second or more. The terms “including” and/or “having”, as used herein, are defined as comprising (i.e., open language). The term “coupled”, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.
References throughout this document to “one embodiment”, “certain embodiments”, and “an embodiment” or similar terms means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of such phrases in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments without limitation.
The term “or” as used herein is to be interpreted as an inclusive or meaning any one or any combination. Therefore, “A, B or C” means any of the following: “A; B; C; A and B; A and C; B and C; A, B and C”. An exception to this definition will occur only when a combination of elements, functions, steps or acts are in some way inherently mutually exclusive.
The drawings featured in the figures are for the purpose of illustrating certain convenient embodiments of the present invention, and are not to be considered as limitation thereto. The term “means” preceding a present participle of an operation indicates a desired function for which there is one or more embodiments, (i.e., one or more methods, devices, or apparatuses for achieving the desired function) and that one skilled in the art could select from these or their equivalent in view of the disclosure herein, and use of the term “means” is not intended to be limiting.
A radar reflector is aimed at effectively reflecting incoming radar electromagnetic signals. An example of a very effective passive reflector is the light reflector used in multiple devices, such as reflective safety vests, road-side posts, reflective safety warning conspicuity tape (typically in yellow or orange color), running shoes, and many more. Radar reflectors function in a very similar manner to optical reflectors, that can be found in safety vests, road-side reflectors, bicycle, and the like, but aims for different wavelengths (i.e., not in the visible band but in the RF band). An example of such reflector is a “corner reflector” (Dihedral, trihedral or octahedral types). Corner reflectors are used to generate a particularly strong radar echo from objects that would otherwise have only very low effective Radar Cross Section (RCS). Corner reflectors can reflect back stronger radar signal at about 20 dB or more than square plate, and even more comparing to objects with non-even, non-metallic surfaces (see
RCS=(πL4)/(3λ2)
Corner reflectors are typically a metal pyramid 13 with the base removed. Energy enters the pyramid and reflects out in a concentrated beam, hence increasing the radar cross-section in that direction. A multidirectional-corner reflector includes two or three electrically conductive surfaces which are mounted crosswise (at an angle of exactly 90 degrees). Incoming electromagnetic waves are backscattered by multiple reflections accurately in that direction from which they come. Thus, even small objects with small RCS yield a sufficiently strong echo. It is in use very extensively by small vessels and is typically installed on the mast.
The single areas of the corner reflector should be large compared to the radar wavelength. The larger a corner reflector is, the more energy is reflected. It can also be constructed in resonance with the radar wavelength. This will increase the echo signals again. To reduce losses caused by other objects, corner-reflectors are mounted as high as possible.
RFID tags 25 use electromagnetic fields to automatically identify and track the object it is attached to. The tags contain electronically-stored information (which can be a unique identification (ID) or other information such as GPS position, descriptive ID, and the like which can be programmed, stored or changed by a local processor.
The system of the present invention can use at least three types of RFID tags: a) Passive, b) Active and c) Continuously-Programmable RFID with a single or double buffer memory to allow updating the tag's data continuously.
In its passive version, the RFID transmitted signal from the reader (also known as the ‘reader’) is modulated and reflected back to the reader with the ID information. Passive tags collect energy from a nearby RFID reader's interrogating radio waves.
RFID—Active tags have a local power source (such as a battery or a solar cell) and have a longer range of operation up to hundreds of meters from the RFID reader. Active RFID is more effective also to fast-moving objects, like an in electronic toll-road. Two different types of active RFID tags are available —transponders and beacons.
Transponders—In a system that uses an active transponder tag, the reader (like in the passive systems) will send a signal first, and then the active transponder will send a signal back with the relevant information. Transponder tags are very efficient because they conserve battery life when the tag is out of range of the reader. Active RFID transponders are commonly used in secure access control and in toll booth payment systems.
Beacons—In a system that uses an active beacon tag, the tag will not wait to hear the reader's signal. Instead, true to its name, the tag will ‘beacon’, or send out its specific information every 3-5 seconds. Beacon tags are very common in the oil and gas industry, as well as mining and cargo tracking applications. Active tag's beacons can be read hundreds of meters away, but in order to conserve battery life, they may be set to a lower transmit power in order to reach around 100 meters read range.
Tags antenna types—the two most common antenna types for an RFID tag is linear- and circular-polarized antennas. An active RFID tag has the advantages of a) longer responds range (usually up to 300 meters) and b) better performances for fast-moving vehicles. Electronic toll road RFIDs typically are active RFID due to the vehicle speed that poses detection difficulties to passive RFIDs.
The VANET protocol is specifically designed to work in an environment without infrastructure where all the vehicles (nodes) can talk to each other (ad-hoc network) and collaboratively generate information about the traffic conditions existing at that moment in a given environment. The disclosed systems and methods of the present invention can be integrated into VANET where the vehicles share the information they picked from the objects (ID, location, etc.) and share it with the neighboring vehicles, via VANET or other similar data-sharing network. Other elements in the disclosed systems and methods of the present invention and are integrated into the vehicle control system as another input.
The system of the present invention can also be integrated with a vehicle-to-vehicle (V2V), vehicle-to-roadside (V2R), Vehicle to Infrastructure (V2I) by becoming an active node in the network with an additional WiFi/WiMax/Bluetooth and the like, communication channels.
A Vehicular Ad-Hoc Network or VANET is a technology that uses moving vehicles as nodes in a network to create a mobile network. VANET turns every participating vehicle into a wireless router or node, allowing vehicles approximately 100 to 300 meters of each other to connect and, in turn, create a network with a wide range. As vehicles fall out of the signal range and drop out of the network, other vehicles can join in, connecting vehicles to one another so that a mobile Internet is created. VANET is a subgroup of MANET where the nodes refer to vehicles. Since roads restrict the movement of vehicles, traffic regulations create a fixed infrastructure at critical locations which can be leveraged by VANET. The primary goal of VANET is to provide road safety measures where information about the vehicle's current speed, location coordinates are passed with or without the deployment of Infrastructure.
Communication Types
Vehicle to Infrastructure/Roadside Communication (v2i/v2r)
Technologies Used
Dedicated Short Range Communication (DSRC)
IEEE 802.11p, a protocol belonging to the IEEE 802.11 family.
Kashif Ali et al. (Reference document no. 1), teaches about installing a Passive-RFID tag to non-intelligent vehicles (non-IVs), in order to assists in their detection by the vehicle's control system, but do not teach about adding a passive RFID tag nor actives RFID to other objects.
A. Vanitha Katherine et al. (reference document No. 2) teaches about using RFID as a means of communication between vehicles (V2V) with VANET concept.
Vehicular Ad-hoc Networks (VANETs) and cooperative collision avoidance (CCA) communication systems for cooperative collision warning and vehicle's navigation, Local Interconnect Network (LIN) and CAN (Controller Area Network), inter-vehicle communication (IVC) protocols. MOST (Media Oriented Systems Transport), FlexRay, and Ethernet have become accepted standards in automotive communications design. Those standards such as Dedicated Short-Range Communication (DSRC) standard are expected to dramatically reduce the number of fatal roadway accidents by providing early warnings and allow safer navigation of the autonomous system.
The aims of the present invention are improving vehicles' control performances by increasing the detectability of low-electromagnetic-profile objects and the information received from those low-electromagnetic-profile objects, by the vehicles' sensors, revealing vital information about the nature, position, speed, etc., of the object, upon a query request from the vehicle, by its radar and an RFID interrogation. Due to its simplicity, high reliability and very low-cost, it can be mounted on every existing or new road element, fixed or moving, providing accurate, reliable, all-weather proof, information to any vehicle and even to multiple vehicles simultaneously. It is integrated into the vehicle's control system enabling it safe and accurate semi or fully automatic navigation.
Referring specifically to
The method of the present invention is based on adding an RFID reader to the set of sensors a vehicle is utilizing for semi or full navigation in the rural or urban environments, as well as adding visibility and detectability enhancing devices (e.g., radar reflectors, RFID tags, etc.) to objects found in such environments. The information provided the system is fed to the vehicle fusion and control unit for processing, control and guidance of the vehicle. This vital information is very accurate vs. the information sensors feed the vehicle control systems (with data on the current and developing state of the vehicle's surroundings). Both operation and safety depend on the accuracy of the sensor system. While in the system of the present invention, the information is set up upon installation at the object or updated by the system in real-time. It reduces significantly the error the vehicle control system may have due to the erroneous analysis of the data it picks. The outcome is much safer navigation.
One of the novelties of the present invention is that while current autonomous (and semi-autonomous) cars rely only on their own sensors and processing capabilities, the disclosed systems and methods of the present invention, add assistance to the vehicle's control system, as objects it encounters “identify” themselves, a) by increasing their “visibility” to the vehicle's sensors by increasing their radar cross section and b) by providing vital information about their nature such as what are they; a child, a road sign meaning a right curve ahead, their accurate position, status, and the like.
As shown in
The same concept is depicted in
An additional embodiment, an optional configuration the reflector is as part of the antenna for the RFID. The current frequencies allocated for vehicle radars are given in
The system of the current invention requires adding an RFID reader 19 to the array of sensors that are connected to the vehicles' sensors-data fusion and control system 15 (as shown in
The system can read multiple objects simultaneously and the objects can respond to multiple interrogations in a very short time and even simultaneously.
An example of a corner radar reflector, a corner reflector 13 principal operation concept 14 is depicted in
An example of the system of the present invention as installed on a bicycle is given in
Example of objects that can benefit from the system of the present invention is given in
Another embodiment of the present invention is a Continuously-Programmable RFID, where the information on the tag is updated frequently and continuously as the parameters of the object it is attached to changes such as location, speed, etc. Such an RFID tag chip can include:
Continuously-Programmable RFID tags life-time is virtually almost unlimited. Current memory technologies (like F-Mem) with 10 billion read & write accesses, enable almost unlimited ‘write’ operations to a tag's memory. It means that one can update the object's position every fraction of seconds. As an example, an object's position can be updated every ten milliseconds (as an example)—an equivalent to less than a foot in traveling distance to a vehicle driving at 100 Km/Hr.) and still have a lifetime of many years.
Another embodiment of the present invention is that it can be implemented on a limited scale if needed (due to budget etc.). As an example, an autonomous vehicle traveling in a fixed and predefined track, like public transportation lanes. Adding the capabilities described in the present invention to a limited number of objects in a limited track simplifies the overall system cost, improves significantly its safety and leave the vehicle's other sensors and radars to focus on only unexpected, spontaneous and unknown events and objects that the vehicle encounters while traveling.
The RFID reader can employ algorithms for anti-collision, which enables the simultaneous reading of multiple RFID tags, for a situation the vehicle may face in a congested traffic and environment with multiple objects.
The anti-collision protocols can be broadly classified into four multiple access protocols.
Anti-collision algorithms to be mentioned (as an example of) are: ALOHA, framed slotted Aloha (FSA), Dynamic Frame Slotted ALOHA (DFSA), progressing scanning (PS) algorithm, and tree-based protocols as probabilistic and deterministic approaches respectively.
Reference: Arundhoti Ferdous, “Comparative Analysis of Tag Estimation Algorithms on RFID EPC Gen-2 Performance” Scholar Commons Citation, 2017.
Fixed positions objects (like roadside elements, roundabout, telephone post, electric-grid posts, road signs, and the like) can be incorporated into the system of the present invention and have their position set up upon installation. A technician programs the RFID tag with the location (coming from a GPS as an example) where he/she placed the road-sign (as an example). The RFID attached to the road-sign will transmit to an interrogator its ID as well as its accurate position. A vehicle applying radar and an RFID reader can get accurate information from those, surrounding objects, identify their nature, and their real-time position by a simple operation. The accurate information is fed to the vehicle control unit that guides the vehicle safely. It eliminates the need for complex processing and/or errors in identifying such objects if one relies only on the vehicle's sensors data, a crucial addition for a vehicle's safe navigation.
This tag information means: It is a small child, with a low RCS, located in Israel with an RFID tag no. 0987654321.
This tag information means: It is a road-sign made of steel, which warns that in 100 yards from the position of the road sign the lane is closed.
Due to the active nature of the RFID, the detection range is much longer (usually about 300 meters).
Objects like traffic-lights that deliver to the driver (nowadays) only information if it can cross the junction (‘green-light’) or it must stop (‘red-light’) and the direction it can drive. However, with the system and method of the present invention, as an example, will update the data in its RFID tags with additional information (to be picked up by the vehicles RFID reader) on the traffic-light current status; which lanes can be used (‘green-light) in which lanes it has to stop (‘red-light’), elapsed time from last change, due time to next change (i.e., switching lanes), and the like.
In a traffic-light as an example, the data transferred by the RFID upon interrogation by the vehicle's RFID reader is the interpretation of the numerical information is in accordance with agreed standard and may differ from one element to the other. (excluding pre-ambles, sync, and other non-data bits); as an example,
This tag information means: This is a traffic-light located in the United States, position at N40° 44.9064′, W073° 59.0735′ (Empire State Building in New York City). It is a 4-way junction; the traffic-light is positioned at the south end of the junction, a vehicle can turn to the left or drive straight (I.e., no right turn allowed). Its current status is Green (means driving is allowed), the green-light is ON for 12 seconds and will be ON in the next 28 seconds. It is made of plastic and ferrometals. (See in
A bicycle, as an example, the data transferred by the RFID upon interrogation by the vehicle's RFID reader is, as an example.
This tag information means: This is a carbon-fiber made bicycles, with a low Radar Cross Section, driving sped is at 25 kilometers per hour in the direction of 270 degrees from north (i.e., westward), and has special warning as it is for a disabled user. The information about the position of the bicycle and its speed is updated at the tag ten times per second (as an example).
Another embodiment of the disclosed systems and methods of the present invention is it Encryption and cyber-security;
Additional Aspects of the Present Invention
It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.
This application claims the benefit of priority of U.S. provisional application Nos. 62/728,884 and 62/752,373, filed 10 Sep. 2018 and 30 Oct. 2018, respectively, the contents of which are herein incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62752373 | Oct 2018 | US | |
| 62728884 | Sep 2018 | US |
