Patent Application
20230397318
The first street lamps were used in Europe during the latter half of the seventeenth century. These lamps consisted of lanterns which were attached to cables strung across the street so that the lantern hung over the center of the street. In France, the police were responsible for operating and maintaining these original street lamps while in England contractors were hired for street lamp operation and maintenance. In all instances, the operation and maintenance of street lamps was considered a government function.
The operation and maintenance of street lamps, or more generally any units which are distributed over a large geographic area, can be divided into two tasks: monitor and control. Monitoring includes the transmission of information from the distributed unit regarding the unit's status and controlling includes the reception of information by the distributed unit.
For the present example in which the distributed units are street lamps, monitoring includes periodic checks of the street lamps to determine if they are functioning properly. The controlling function comprises turning the street lamps on at night and off during the day.
Currently, most street lamps still use arc lamps for illumination. The mercury-vapor lamp is the most common form of street lamp in use today. In this type of lamp, the illumination is produced by an arc which takes place in a mercury vapor.
The mercury-vapor lamp includes an arc tube 110 which is filled with argon gas and a small amount of pure mercury. The arc tube 110 is mounted inside a large outer bulb 120 which encloses and protects the arc tube. Additionally, the outer bulb may be coated with phosphors to improve the color of the light emitted and reduce the ultraviolet radiation emitted. Mounting of the arc tube 110 inside the outer bulb 120 may be accomplished with an arc tube mount support 130 on the top and a stem 140 on the bottom.
Main electrodes 150a and 150b, with opposite polarities, are mechanically sealed at both ends of arc tube 110. The mercury-vapor lamp requires a sizeable voltage to start the arc between the main electrodes 150a and 150b.
The starting of the mercury-vapor lamp is-controlled by a starting circuit (not shown in
During the starting operation, electrons move through a starting resistor 160 to a starting electrode 170 and across a short gap between the starting electrode 170 and the main electrode 150b of opposite polarity. The electrons cause ionization of some of the argon gas in the arc tube. The ionized gas diffuses until a main arc develops between the two opposite polarity main electrodes 150a and 150b. The heat from the main arc vaporizes the mercury droplets to produce ionized current carriers. As the lamp current increases, the ballast acts to limit the current and reduce the supply voltage to maintain stable operation and extinguish the arc between the main electrode 150b and starting electrode 170.
Because of the variety of different types of starter circuits, it can be difficult to characterize the current and voltage characteristics of the mercury-vapor lamp. Often, the mercury-vapor lamp may require minutes of warm-up before light is emitted. Additionally, if power is lost, the lamp must cool and the mercury pressure must decrease before the starting arc can start again.
The mercury-vapor lamp has become one of the predominant types of street lamp with millions of units produced annually. The current installed base of these street lamps is enormous with more than 500,000 street lamps in Los Angeles alone. The mercury-vapor lamp is not the most efficient gaseous discharge lamp, but is preferred for use in street lamps because of its long life, reliable performance, and relatively low cost.
Although the mercury-vapor lamp has been used as a common example of current street lamps, there is increasing use of other types of lamps such as metal halide, high pressure sodium and light emitting diodes (LEDs). All of these types of lamps require a starting circuit which makes it difficult to characterize the current and voltage characteristics of the lamp.
Most cities currently use automatic lamp control units to control the street lamps. These lamp control units provide an automatic, but decentralized, control mechanism for turning the street lamps on at night and off during the day.
A conventional street lamp assembly 201 includes a lamp sensor unit 210 which in turn includes a light sensor 260 and a relay 270 as shown in
From a physical standpoint, most lamp sensor units 210 use a standard three prong plug, for example a twist lock plug, to connect to the back of lamp assembly 230. The three prongs couple to hot line 280a, switched line 280c, and neutral lines 280b and 280d. In other words, the neutral lines 280b and 280d are both connected to the same physical prong since they are at the same electrical potential. Some systems also have a ground wire, but no ground wire is shown in
Power source 220 may be a standard 115 Volt, 60 Hz source from a power line. Of course, a variety of alternatives are available for power source 220. In foreign countries, power source 220 may be a 220 Volt, 50 Hz source from a power line. Additionally, power source 220 may be a DC voltage source or, in certain remote regions, it may be a battery which is charged by a solar reflector.
An exemplary operation of the lamp sensor unit 210 is as follows. At sunset, when the light from the sun decreases below a sunset threshold, the light sensor 260 detects this condition and causes the relay 270 to close. Closure of the relay 270 results in electrical connection of the hot line 280a and the switched line 280c with power being applied to the starting circuit 250 of the lamp assembly 230 to ultimately produce light from the lamp 240. At sunrise, when the light from the sun increases above a sunrise threshold, the light sensor 260 detects this condition and causes the relay 270 to open. Opening of relay 270 eliminates electrical connection between the hot line 280a and the switched line 280c and causes the removal of power from the starting circuit 250 which turns the lamp 240 off.
The lamp sensor unit 210 provides an automated, distributed control mechanism to turn the lamp assembly 230 on and off. However, it does not provide a mechanism for centralized monitoring of the street lamp to determine if the lamp is functioning properly. This problem is particularly important with respect to the street lamps on major boulevards and highways in large cities. When a street lamp burns out over a highway, it is often not replaced for a long period of time because the maintenance crew only schedules a replacement lamp when someone calls the city maintenance department and identifies the exact pole location of the malfunctioning street lamp. Since most automobile drivers will not stop on the highway just to report a malfunctioning street lamp, the malfunctioning lamp can go unreported indefinitely.
Additionally, if a lamp is producing light but has a hidden problem, visual monitoring of the lamp is not able to detect the problem. Some examples of hidden problems relate to current use by the lamp (e.g., a lamp drawing significantly more current than is normal) or voltage use by the lamp (e.g., the power supply is not supplying the appropriate voltage level to the street lamp).
Furthermore, the conventional system of lamp control, in which an individual light sensor is located at each street lamp, is a distributed control system which does not allow for centralized control. For example, if the city or other monitoring organization wanted to turn on or off all of the street lamps in a certain area at a certain time, this could not be done because of the distributed nature of the present lamp control circuits.
Because of these limitations, a new type of distributed unit monitoring and control system is needed which allows centralized monitoring and/or control of the distributed units in a geographical area. Further, a new type of lamp monitoring and control system is needed which allows centralized monitoring and/or control of the street lamps in a geographical area. There is also a need for an inexpensive, reliable monitoring and control system. Further there is a need for a monitoring system that is able to handle the traffic generated by communication with the millions of currently installed street lamps. Further, there is a need for a monitoring system that can be easily integrated into existing light infrastructures and devices. Further still, there is a need for a control system that can be easily integrated into existing light infrastructures and devices.
Although the above discussion has presented street lamps as an example, there is a more general need for a new type of monitoring and control system which allows centralized monitoring and/or control of units distributed over a large geographical area.
One embodiment relates to at least one lamp monitoring device configured to be disposed at a location of a lamp. The lamp monitoring device includes a processing circuit, a transmit circuit, and an optical sensor configured to collect image data associated with the lamp. The at least one lamp monitoring device is adapted to wirelessly transmit monitoring data associated with the image collected by the optical sensor.
One embodiment relates to a lamp monitoring and control system for monitoring and controlling at least one lamp, including at least one lamp monitoring and control device, adapted to be coupled to a lamp, disposed substantially near a top of a lamp pole. The lamp monitoring and control device includes a processing circuit, a transmit circuit, and an optical sensor configured to collect image data associated with the lamp. The system further includes at least one station configured to receive monitoring data from the at least one lamp monitoring and control device; a network communication server in communication with the at least one station; and at least one user interface unit in communication with the network communication server. The at least one lamp monitoring and control device is adapted to wirelessly transmit the monitoring data to the at least one station without prompting from the at least one station.
Another embodiment relates to a lamp monitoring and control system for monitoring and controlling at least one lamp, including at least one lamp monitoring and control device, adapted to be coupled to a lamp, disposed substantially near a top of a lamp pole. The lamp monitoring and control device includes a processing circuit, a transmit circuit, a power source control module, and an optical sensor configured to collect image data associated with the lamp monitoring and control system. The system further includes at least solar panel provided in proximity to the lamp, the solar panel being configured to provide power to the lamp; at least one station configured to receive monitoring data from the at least one lamp monitoring and control device; a network communication server in communication with the at least one station; and at least one user interface unit in communication with the network communication server. The at least one lamp monitoring and control device is adapted to wirelessly transmit the monitoring data to the at least one station without prompting from the at least one station. The power source control module controls and monitors the power flow from the solar panel to the lamp.
Yet another embodiment relates to a method for monitoring a lamp assembly. The method includes capturing image data related to an object of interest with the optical sensor disposed near an object of interest related to the lamp assembly, and transmitting the image data from the optical sensor to a processing circuit of a lamp monitoring and control device. The method also includes transmitting the image data from the processing circuit to a base station using a transmit unit.
The exemplary embodiments will be described in detail with reference to the following drawings in which like reference numerals refer to like elements wherein:
The exemplary embodiments of a lamp monitoring and control system (LMCS) and method, which allows centralized monitoring and/or control of street lamps, are described with reference to the accompanying figures. While the embodiments are described with reference to an LMCS, the disclosure is not limited to this application and can be used in any application which requires a monitoring and control system for centralized monitoring and/or control of devices distributed over a large geographical area. Additionally, the term street lamp in this disclosure is used in a general sense to describe any type of street lamp or light, security lamp, area lamp, or outdoor lamp.
The power source 220 may be a standard 115 volt, 60 Hz source supplied by a power line in some embodiments. A variety of alternatives are available for the power source 220. In foreign countries, the power source 220 may be a 220 volt, 50 Hz source from a power line. Additionally, the power source 220 can be a DC voltage source, such as a battery which is charged by a solar panel, wind turbine, or other power generation device, as described in more detail below. Power source 220 can be any device for providing electrical energy to the lamp monitoring and control unit 310 and/or lamp assembly 230.
In some embodiments, the lamp monitoring and control unit 310 can include the components of the lamp sensor unit 210. In other embodiments, the lamp monitoring and control unit 310 can be provided separately from the lamp sensor unit 210. The lamp sensor unit 210 includes a light sensor 260 and a relay 270 which is used to control lamp assembly 230 by automatically switching the hot line 280a to the switched line 280c depending on the amount of ambient light received by light sensor 260 as shown in
The lamp monitoring and control unit 310 provides several functions including a monitoring function which is not provided by the lamp sensor unit 210. The lamp monitoring and control unit 310 is electrically located between the external power source 220 and the starting circuit 250 of lamp assembly 230. The power source 220 is electrically connected to the lamp monitoring and the control unit 310 with a hot line 280a and a neutral line 280b. The lamp monitoring and control unit 310 is electrically connected to the starting circuit 250 of the lamp assembly 230 with a switched line 280c and a neutral line 280d in some embodiments.
From a physical standpoint, the lamp monitoring and control unit 310 uses a standard three-prong plug to connect to the back of the lamp assembly 230 in some embodiments. The three prongs in the standard three-prong plug represent hot line 280a, switched line 280c, and neutral lines 280b and 280d. In other words, the neutral lines 280b and 280d are both connected to the same physical prong and share the same electrical potential. In some embodiments, the lamp monitoring and control unit 310 may be positioned above the lamp assembly 230 in some embodiments.
Although use of a three-prong plug is recommended because of the substantial number of street lamps using this type of standard plug, additional types of electrical connection may be used without departing from the disclosure of the exemplary embodiments. For example, a standard power terminal block or AMP power connector is used in some embodiments.
In some embodiments, the lamp monitoring and control circuit 310 includes a sensor 311. The sensor 311 is a camera, optical sensor, an environmental sensor, a Geiger counter, an olfaction sensor, an acoustic sensor, or a vibration sensor in some embodiments. Sensor 311 provides data related to the lamp 240 or the environment there of. The data can be used to provide warnings, summon maintenance personnel, turn lamp 240 on or off, or be used in other environmental analysis.
The processing and sensing unit 412 is electrically connected to the hot line 280a, the switched line 280c, and the neutral lines 280b and 280d. Furthermore, the processing and sensing unit 412 is connected to the TX unit 414 and the RX unit 416. In an exemplary application, the TX unit 414 can be used to transmit monitoring data and the RX unit 416 can be used to receive control information. For applications in which external control information is not required or desired, the RX unit 416 can be omitted from lamp monitoring and control unit 310.
The lamp monitoring and control unit 310 further includes an optical sensor 430 (e.g., sensor 311 (
The image data collected by the optical sensor 430 can be utilized for a variety of monitoring and diagnostic tasks. In one embodiment, the image data collected by the optical sensor 430 can be used to determine if the lamp 240 is on or off. The determination of whether the lamp is on or off can be made locally, by the processing circuit 420. For example, the image data can be processed to determine the brightness of the image. If the image is above a predetermined brightness threshold, the lamp monitoring and control unit 310 transmits a signal via the TX unit 414 unit indicating that the lamp 240 is on in some embodiments. If the image is below the predetermined brightness threshold, the lamp monitoring and control unit 310 transmits a signal via the TX unit 414 unit indicating that the lamp 240 is off in some embodiments. In other embodiments, the image data is transmitted to a remote location via the TX unit 414 and the status of the lamp 240 is determined by visual verification of a remote user or by analysis of a remote computer. A timestamp or other additional data is included with the image data transmission, in some embodiments.
In other embodiments, the image data collected by the optical sensor 430 can be utilized to determine the health or estimated remaining lifespan of the lamp 240. The lamp 240 can be a high pressure sodium lamp. Such a lamp loses sodium and experiences an increases internal pressure and voltage requirement as it ages. If the voltage requirements exceed the output of the starting circuit 250, the lamp will turn off, cool down, and then turn back on (e.g., cycle). The image data collected by the optical sensor 430 can be utilized to detect cycling behavior, indicating that the lamp 240 is to be replaced. In some embodiments, time stamps associated with a changing image are used to determine cycling. In some embodiments, on/off times changing within a frequency less than daily are an indication of cycling. The cycling determination can be made locally, by processing circuit 420 or may be made remotely. In some embodiments, the cycling determination is made locally and a cycling warning is transmitted to a remote user instead of the image data.
In other embodiments, the lamp 240 can be an LED lamp. The high temperatures at which LEDs can operate can influence the long-term color stability of the lamp. The phosphors used to convert narrow-band LED emission to a broader range of wavelengths can settle, curl, delaminate, or otherwise change the amount of photons that are converted, with the effect being that perceived color of the LED lamp can shift over time. The image data collected by the optical sensor 430 can be utilized to detect color shift of the lamp 240.
In some embodiments, a baseline image is sent and image data is not resent until there is a substantial change in the image. For example, in some embodiments, after the baseline image is sent, image data is not transmitted until there is a substantial change in the brightness of the lamp 240 or a substantial change in the color of the lamp 240. Various video processing and image processing techniques can be utilized to analyze the image data including image compare algorithms. The memory 424 can store baseline color or brightness images for the image comparison in some embodiments. The baseline and brightness images can be preset or captured during installation or calibration. Target identification algorithms can be utilized to identify objects in the sense image that may affect the sensing of color or brightness in the some embodiments. Filtering and integration techniques can also be used to increase the accuracy of the sensed image in some embodiments.
In some embodiments, the optical sensor 430 is not provided in the lamp monitoring and control unit 310 above the lamp assembly 230. For example, in some embodiments, the optical sensor 430 is coupled to a pole to which the lamp assembly is coupled and is oriented toward the lamp 240.
In some embodiments, the optical sensor 430 is utilized to collect other data. For example, the optical sensor 430 can collect environmental data to monitor natural phenomena, such monitoring river levels to predict flash floods; the optical sensor 430 can collect data to monitor man-made structures, such as monitoring bridges or other structures to measure vibration and deflection of the structures; or the optical sensor 430 can collect data on human activity, such as monitoring crowd density or detecting muzzle flashes from firearms.
In some embodiments, the optical sensor 430 is oriented to collect images of the surface of a solar panel. The image data collected by the optical sensor 430 is analyzed to determine when maintenance is required for a solar panel by monitoring the amount of dirt, dust, or other debris collected on the surface of the solar panel. The analysis of the image data is accomplished automatically and a warning is transmitted to a person, in some embodiments. In other embodiments, the image data is analyzed directly by a person to determine if maintenance of the solar panel is needed. In some embodiments, the solar panel is associated with providing power to a sign, a lamp, a sensor, or other device. In some embodiments, the solar panel is part a solar farm or is a panel on a building, house, or other facility.
As shown in
Communication between monitoring and control units 310a-d and the base station 810 can be accomplished in a variety of ways, depending on the application, such as using: RF, wire, coaxial cable, or fiber optics. For lamp monitoring and control system 800, RF is the preferred communication link due to the costs required to build the infrastructure for any of the other options.
In some embodiments, control units 310 can provide a wireless network access using the transmit units 414 and receive units 616. For example, the control units 310 can provide a wireless network for a restricted group of people, such as city workers, police, maintenance personnel, or can provide a public wireless network.
Although the example of geographic area is used to group monitoring and control units 310a-c, it is well known to those skilled in the art that other groupings can be used. For example, to monitor and control lamp assemblies made by different manufacturers, monitoring and control system 900 can use groupings in which base station 810a services one manufacturer and base station 810b services a different manufacturer. In this example, bases stations 810a and 810b can be servicing overlapping geographical areas.
A communication server 912 is coupled to a station (e.g., base station 810 and/or main station 910. In some embodiments, communication server 912 is coupled to the station with an antenna or an array of antennas or with a wired connection (e.g., a standard phone line, DDS line, ISDN line, Ti, fiber optic line, etc.). A user interface unit 914 is coupled to the communication server. The user interface unit 914 allows a user to view the image data or other data, warnings, or control signals transmitted by the control unit 310.
While the lamp monitoring and control unit 310 is generally described as being used with a lamp assembly in the form of a street lamp, in other embodiments, the lamp assembly can be any illumination device for illuminating an outdoor space. For example, in other embodiments, the lamp monitoring and control unit 310 can be used to monitor and control a lamp assembly illuminating a parking lot, a park, an outdoor stadium, or other outdoor sport facility (e.g., basketball courts, tennis courts, etc.).
The foregoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. The description of the present invention intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.
This application claims the benefit of and priority to U.S. Provisional Application No. 63/349,435, filed Jun. 6, 2022, the entire disclosure of which is incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 63349435 | Jun 2022 | US |
