Patent Application
20160107207
The present invention relates to apparatuses, systems, and methods for the cleaning of surfaces, and in particular though non-limiting embodiments, to apparatuses, systems, and methods for cleaning containers, tanks, or vessels by fluidizing and removing materials within their interiors using a programmable and articulating arm.
Conventional tank cleaning is often a long, stringent, hazardous, and labor-intensive task. Conventional methods of tank and vessel cleaning require operator exposure to dangerous environments. The work of an operator typically involves manually placing a remotely operated vehicle (ROV) into position in an enclosed and/or confined area, locking the ROV into place, controlling the ROV to perform a specified task, and removing the ROV from the enclosed area. ROVs have traditionally been used for a variety of reasons, including reduced costs, increased time-effectiveness, increased strength capabilities over human workers, and improved safety by reducing man hours spent in confined spaces.
Existing remote tank cleaning systems include a nozzle configured to direct a fluid stream to dislodge, dilute, or dissolve settled solids from tank interiors. These systems generally require extensive mounting or setup within these tanks or containers prior to cleaning, during which workers may be subject to prolonged exposures to the contents being cleaned. Mounted systems may only be able to mount in a limited number of locations within the tanks or containers, limiting the utility of the system. Some systems include extensive robotic components that are bulky, heavy, and difficult to assemble and/or disassemble. Often, the systems cannot be utilized in remote or difficult to reach interiors of tanks, containers, and/or vessels because of the difficulty involved in bringing the system to the site. The systems usually require one or more booms or cranes to place the system near or into a target enclosed area. Additionally, cleaning systems typically involve attachment to or placement upon a floor of a target enclosed area, meaning that the system is placed upon and/or covering a portion of the very sludge/materials the system is intended to clean. Floor mounted systems must also account for other issues in the floor, such as baffles, irregular surfaces, and debris.
On the other hand, cleaning systems that are less bulky or require less assembly are typically insufficiently stable to withstand high water pressures necessary to fluidize settled solids and/or sludge to where they can be easily pumped out. In such cases, the solids and/or sludge must be physically and/or mechanically removed by workers from the interior of enclosed areas, placing the workers in a dangerous and/or toxic environment and therefore at greater risk of exposure to health hazards and injuries.
Additionally, existing tank cleaning systems use fluid directing systems that result in random, wasted movement. For example, some cleaning systems utilize gamma jets that perform cleaning via a 360° spherical spray pattern/movement. However, in these systems, it is not possible to control the cycle of a gamma jet once activated, thereby making it difficult to focus on specific areas in need of cleaning.
Accordingly, a need exists for an improved apparatus, system, and method to remotely remove materials, including settled solids, fluids, slurries, and/or sludge, from a vessel, container, and/or tank interior in a manner that is more efficient and safe than existing systems.
Embodiments of the present invention provide for improved methods, systems, and apparatuses for cleaning by implementation of a programmable, portable, multi-axis articulating arm (MAAA) having a plurality of connected arm segments. Embodiments of the present invention provide for purpose driven, focused movement, rather than random, wasted movement. The MAAA may be connected to a track system. Each arm segment may have sensor and positioning components configured to provide a signal to a Programmable Logic Control (PLC) device to ensure correct positioning of the MAAA and track system according to pre-programmed algorithms. The algorithms may provide an efficient manner of cleaning an enclosed area without requiring constant repetitious movements from an operator.
Embodiments of the present invention are configured to work integrally with an operator and amplify the impact of an operator by taking over the most repetitious of tasks. The interoperability of the system with the operator provides a safer and higher quality end product. The operator may be incorporated in the process by overseeing and ensuring the quality of work by the automated process. The programmable MAAA is designed to apply state of the art cleaning techniques with better-than-human accuracy. For example, a typical crew of seven workers may be replaced by a crew of two, resulting in cost reductions and making programmed cleaning an economically viable alternative on a greater number of enclosed areas, potentially leading to an increase in skilled employment in the trade.
The present invention also addresses major safety concerns by reducing and/or eliminating man-hours spent in confined spaces. Embodiments of the present invention provide for a safe, efficient, and cost-saving alternative to placing workers in confined spaces and allow for completion of a safe and successful cleaning job while reducing project turnaround time.
In an example embodiment of the present disclosure, a cleaning apparatus is provided. The cleaning apparatus includes a base having at least one magnet; an arm having a first end attached to the base and extending away from the base; and a nozzle attached to a second end of the arm. The arm may include at least two rotatable joints allowing for manipulation of the nozzle. The base may be configured to magnetically attach to a metal surface. The at least one magnet may be an electromagnet. The apparatus may further include at least one additional magnet configured to attach to the metal surface. The base may include base extensions extending from the at least one magnet at a first end and attaching to a plate at a second end. The apparatus may further include a support beam having a first end attached to the metal surface and a second end attached to the plate. The arm may include a first arm member attached to the plate; and a second arm member attached to the first arm member. The first arm member may be configured to rotate relative to the plate around a first axis. The second arm member may be configured to rotate relative to the first arm member around a second axis that is substantially perpendicular to the first axis. The apparatus may include a pressure line mount configured to facilitate flow of high pressure fluids for cleaning. The pressure line mount may be connected to the second arm member via attachment to the nozzle at a first end and a pressure line at a second end. The nozzle may include dual spay ends. The nozzle may rotate such that each dual spray end spins and provides dual rotating jets of water for breaking-up materials.
The apparatus may include control lines connected to a control station, the control lines configured to control movement of the at least two rotatable joints. The control lines may be at least one of electrical, pneumatic, and hydraulic. The apparatus may be configured to be disassembled into at least two separate components. The at least two separate components may include handles. The arm may include additional arm members such that the arm has more than two axes of articulated movement. The first arm member may include first and second hinge connectors and the second arm member may include third and fourth hinge connectors. The first hinge connector may be fixedly attached to the plate and the second hinge connector may be rotatably attached to the first hinge connector such that the second hinge connector rotates relative to the plate around the first axis. The third hinge connector may be fixedly attached to the second hinge connector and the fourth hinge connector may be rotatably attached to the third hinge connector such that the fourth hinge connector rotates relative to first arm member around the second axis.
In an example embodiment of the present disclosure, a system for cleaning an area is provided. The system includes a cleaning apparatus; at least one camera mounted within the area; and a vacuum line. The cleaning apparatus includes a base having at least one magnet; an arm having a first end attached to the base and extending away from the base; and a nozzle attached to a second end of the arm. The arm may include at least two rotatable joints allowing for manipulation of the nozzle. The apparatus may be configured to spray a fluid via the nozzle and the vacuum line removes the fluid and any materials contained in the fluid. An operator may view the apparatus and area via the at least one camera. The system may include control lines configured to control movement of the at least two rotatable joints. The control lines may be connected to a control station and configured to allow the operator to remotely operate the apparatus. The system may include first and second longitudinal bars movably attached to each other. The apparatus may be movably attached to the first bar. The second bar may be movably attached to a mounting structure. The first and second bars and the apparatus may be movable in multiple directions and axes. The first and second bars may be perpendicularly attached to each other. The apparatus may be magnetically attached to the first bar via the at least one magnet. The second bar may be perpendicularly attached to the mounting structure.
In an example embodiment of the present disclosure, a cleaning and track system is provided. The system includes a cleaning apparatus, a track system, at least one camera mounted within the area; and a vacuum line. The apparatus includes a base; an arm having a first end attached to the base and extending away from the base; and a nozzle attached to a second end of the arm. The arm may include at least two rotatable joints allowing for manipulation of the nozzle. The track system may include first and second longitudinal bars movably attached to each other. The second bar may be movably attached to a mounting structure. The first and second bars may be movable in multiple directions and axes. The apparatus may be movably attached to the track system. The apparatus may be configured to spray a fluid via the nozzle and the vacuum line removes the fluid and any materials contained in the fluid. An operator may view the apparatus and area via the at least one camera. The system may include control lines configured to control movement of the at least two rotatable joints. The control lines may be connected to a control station and configured to allow the operator to remotely operate the apparatus and track system.
In an example embodiment of the present disclosure, a method of cleaning an area is provided. The method includes magnetically mounting a cleaning apparatus within the area; connecting the cleaning apparatus to a high pressure fluid line; remotely operating the cleaning apparatus to control a direction of flow from the high pressure fluid line; directing a flow of fluids towards material on a surface of the area to remove the material from the surface; and removing the fluids and material via a vacuum line. The cleaning apparatus includes a base having at least one magnet; an arm having a first end attached to the base and extending away from the base; and a nozzle attached to a second end of the arm. The arm may include at least two rotatable joints allowing for manipulation of the nozzle. The apparatus may be remotely operated via control lines connected from a control station to the apparatus, the control lines configured to control movement of the at least two rotatable joints. The method may include magnetically attaching the at least one magnet to a track system. The track system may include first and second longitudinal bars movably attached to each other. The apparatus may be movably attached to the first bar. The second bar may be movably attached to a mounting structure. The first and second bars and the apparatus may be movable in multiple directions and axes.
The apparatus may be programmed by the steps of instructing a route to the apparatus by the steps of controlling the apparatus and defining the route via implementation of a starting cleaning sequence, and logging resulting route data from sensor and positioning components to a memory. The sensor and positioning components may be located on at least one of the apparatus and track system. The route may include an initial cleaning of the area including a sequence of maneuvers positioning the apparatus for optimal cleaning purposes. The apparatus may further be programmed by the steps of processing logged route data into a route profile, and reproducing the route profile automatically using a Programmable Logic Control (PLC) device. The route profile may include a defined optimal cleaning sequence. The apparatus may be operated by the steps of implementing the starting cleaning sequence using the PLC device; sending the signal to an Electro-Hydraulic Flow Control (EHFC) device via the PLC device; positioning the apparatus and arm in an optimal cleaning position based on the signal and flow via the EHFC device; and performing a cleaning motion for a pre-determined amount of time according to the defined optimal cleaning sequence. The PLC device may be configured to receive an electrical signal from the sensor and positioning components once the starting cleaning sequence is implemented. The EHFC device may be configured to provide at least one of hydraulic, pneumatic, and electrical flow. The PLC device may be configured to repeat the defined optimal cleaning sequence by simultaneously sending and receiving signals. The method may include observing movements of the cleaning apparatus and track system via at least one camera mounted within the area or on the apparatus. The steps for operating the apparatus may be repeated until the area is cleaned. The method may include turning off the at least one magnet to dismount the cleaning apparatus. The at least one magnet may be electro-magnetic.
In an example embodiment of the present disclosure, a cleaning apparatus is provided. The apparatus includes a base; an arm having a first end attached to the base and extending away from the base; and a nozzle attached to a second end of the arm. The arm may include at least two rotatable joints allowing for manipulation of the nozzle. The apparatus may include base extensions extending from the base at a first end and attaching to a plate at a second end. The arm may include a first arm member attached to the plate; and a second arm member attached to the first arm member. The first arm member may be configured to rotate relative to the plate around a first axis. The second arm member may be configured to rotate relative to the first arm member around a second axis that is substantially perpendicular to the first axis. The apparatus may include a pressure line mount configured to facilitate flow of high pressure fluids for cleaning. The pressure line mount may be connected to the second arm member via attachment to the nozzle at a first end and a pressure line at a second end. The apparatus may include control lines connected to a control station, the control lines configured to control movement of the at least two rotatable joints.
Embodiments of the present invention include a cleaning apparatus having a programmable, portable, MAAA. The apparatus may be mounted on a wall in an interior of an enclosed area to be cleaned. The enclosed area may include interiors and/or exteriors of containers, vessels, tanks, or any other structures that require cleaning. The apparatus may also be mounted on a manhole or similar opening. The apparatus may include at least one magnet configured to magnetically mount the apparatus. Magnetic mounting allows for the apparatus to be mounted at virtually unlimited locations with the enclosed area, allowing for more focused and efficient cleaning and simple removal. The apparatus may also be bolted in place. The apparatus may include a high pressure fluid line and high pressure nozzles. The apparatus may be configured for remote operation by an operator outside of the enclosed area being cleaned.
Embodiments of the present invention also include a cleaning and track system. Cleaning and track system includes a cleaning apparatus as described herein mounted to a track system and/or mounting structure placed within an enclosed area whereby the MAAA of apparatus may be movable through additional axes within an enclosed area. Cleaning and track system may be controlled manually or from pre-programmed algorithms through a PLC device. Sensor and positioning components on the MAAA and/or track system may provide a signal to the PLC device to ensure correct positioning of the MAAA and/or track system according to the pre-programmed algorithms.
Cleaning apparatus and/or cleaning and track system are configured such that they may be attached within the enclosed area at a location near an area targeted for cleanup. Embodiments of the present invention are durable and allow for precise control of water flows, which may be directed at specific problem or target areas rather than merely cycling to clean the entire enclosed area. Performing targeted cleaning allows for increased efficiency and decreased waste.
Referring now to
First and second arm members 122, 136 may each include at least one rotatable joint configured so that the arm members 122, 136 may be manipulated in multiple directions. In exemplary embodiments, first arm member 122 includes first and second hinge connectors 140, 139. First hinge connector 140 is fixedly attached to plate 124. Second hinge connector 139 is rotatably attached to first hinge connector 140 such that second hinge connector 139 rotates relative to plate 124 along a first axis of rotation. As shown in
Second arm member 136 includes third and fourth hinge connectors 137, 135. Third hinge connector 137 is fixedly attached to second hinge connector 139. Fourth hinge connector 135 is rotatably attached to third hinge connector 137 such that fourth hinge connector 135 rotates relative to first arm member 122 along a second axis of rotation that is substantially perpendicular to the first axis of rotation of the first arm member 122 relative to plate 124. As shown in
The combination of the rotation of first arm member 122 and second arm member 136 allows for MAAA 103 to be moved up and down and side to side, covering the entire surface of the interior of the enclosed area. In some embodiments, first arm member 122 and second arm member 136 may include swivel connectors and/or any other connections/joints to facilitate cleaning by apparatus 100. In other embodiments, the number and location of the hinge connectors and/or swivel connectors may be varied to achieve movement of apparatus 100 along additional axes.
Elbow member 120 is attached to second arm member 136. Particularly, elbow member 120 is attached to fourth hinge connector 135. See
Apparatus 100 includes a base with a pair of magnets 128 configured to mount apparatus 100 to wall 132 within an enclosed area. See
Base may include base extensions 126 connected to magnets 128 at one end and plate 124 at a second end. See, e.g.,
Apparatus 100 may include handles 114 to allow a worker to carry components of MAAA 103 to a desired location. See, e.g.,
First and second arm members 122, 136 may be connected to control lines 134, 138. See, e.g.,
Apparatus 100 may be remotely controlled by an operator at a control station external to the enclosed area. Control station is operatively connected to the apparatus 100 and transmits signals to apparatus 100 via control lines 134, 138 based on the operator's input at the control station. In embodiments, a camera may be attached to the enclosed area prior to apparatus 100 being mounted to the enclosed area, or may be attached to apparatus 100 prior to mounting. Display device may also be provided at the control station so that the operator may monitor apparatus 100 inside the enclosed area via the camera and make any necessary adjustments to apparatus 100.
In some embodiments, apparatus 100 may be attached to an external plate 200 and placed into an enclosed area at a manway access point 141. See, e.g.,
Referring now to
As shown in
Cleaning apparatus 100 is attached to a track/drive system 414. As shown, the track/drive system 414 includes two generally inverted U-shaped structures or bars 416, 417 attached to each other. In an exemplary embodiment, bars 416, 417 are perpendicularly attached to each other. In other embodiments, the structures or bars 416, 417 may have a generally inverted V-shape or any other shape. Each inverted U-shaped bar 416, 417 includes a rod 419, 420 movably attached between two opposing generally inverted and curved hook or T-shaped track supports 421, 422. Alternatively, the track supports 421, 422 may have any other shape suitable for performing functions of the track/drive system 414. In exemplary embodiments, rods 419, 420 may be Acme threaded rods mounted within bars 416, 417. In some embodiments, rods 419, 420 may be mounted within bars 416, 417 via a threaded rod-nut connection. Rods 419, 420 may be connected at their ends to motors and configured to generate linear motion and provide rapid, lateral movement. Nuts may further be welded to each end of rods 419, 420 to limit movement of rods 419, 420 within bars 416, 417. Rods 419, 420 may be rotated within each bar 416, 417 via hydraulic, pneumatic, and/or electrical power.
Cleaning apparatus 100 is attached to first bar 416 such that cleaning apparatus 100 may be movable and/or driven along the length of the first bar 416. Cleaning apparatus 100 may be magnetically attached to first bar 416 or attached via a first trolley unit 450 as described herein. Alternatively, cleaning apparatus 100 may be attached to first bar 416 via any other attachment mechanisms. Apparatus 100 may be remotely controlled and mechanically driven along first bar 416. As shown in
Referring to
In some embodiments, ends of track supports 421, 422 may further extend away from bars 416, 417 so as to attach bars 416, 417 to a wall or other surface via magnets or any other temporary or permanent attachment mechanisms. In embodiments, bar 416 may be pre-mounted to an interior surface of a container and bar 417 may be subsequently inserted into the container and mounted onto bar 416.
Cleaning and track system 400 may be attached to a mounting bar/support structure 415 via magnets or any other temporary or permanent attachment mechanisms. Cleaning and track system 400 may be strategically placed according to any specific positioning required for comprehensive movement within an enclosed area. In exemplary embodiments, mounting bar 415 is a longitudinal I-beam. However, mounting bar 415 may be a rounded rod/bar and/or have any other shape for attachment of cleaning and track system 400. As shown in
Depending on the configuration of an area to be cleaned, multiple different arrangements of the track system 400 and/or mounting bar 415 are possible. Although disclosed as being connected perpendicularly, the first and second bars 416, 417 and mounting structure 415 may be attached to each other in any other configuration necessary to assist apparatus 100 in performing its cleaning functions. In embodiments, each component of the cleaning and track system 400, including cleaning apparatus 100, first bar 416, and second bar 417, as well as mounting bar/support structure 415 may be separately mounted within or outside a container, and/or may be maneuvered into the container as separate components or as a pre-mounted system/apparatus prior to cleaning. For example, in some embodiments, track/drive system 414 may be mounted within container, and apparatus may be lowered into container and attached to track/drive system 414. In other embodiments, apparatus 100 may be mounted within container and track/drive system 414 may be lowered into container and attached to apparatus 100. In yet other embodiments, first bar 416 of track/drive system 414 may be mounted within container and second bar 417 of track/drive system 414 may be lowered into container and attached to first bar 416. In some embodiments, mounting bar 415 may be mounted within container and track system 400 and/or its individual components may be lowered into container and attached to mounting bar 415.
A vacuum line may be placed on or near the floor of an area to be cleaned and may be configured to remove water and fluidized debris/materials from the area. One or more cleaning apparatuses 100 and/or cleaning and track systems 400 may be placed within an area to be cleaned. Cleaning and track system 400 may further be used in conjunction with other cleaning systems, for example, the systems described in U.S. patent application Ser. Nos. 13/135,018 and 14/530,455, all of which are incorporated herein by reference.
Cleaning and track system 400 may be controlled manually or from pre-programmed algorithms through a PLC device. In exemplary embodiments, the cleaning and track system 400 includes sensor and positioning components affixed to the MAAA 103 and/or track/drive system 414, and that are configured to send relevant positioning and other data to the PLC device. Sensor and positioning components may include a laser based device, an ultrasonic based device, an optical based device, or other similar devices. In particular embodiments, the laser sensor may be a rangefinder sensor such as a SICK Optic Laser Scanner.
Cleaning and track system 400 may be programmed via operational steps of Instructing (or Teaching), Route Profiling, and Reproduction (or Playback). Methods using these particular operational steps are disclosed in U.S. Pat. No. 8,260,483, which is incorporated herein by reference. Specifically, the patent discloses methods including instructing/teaching a route and logging resulting route data from sensors to a memory; processing the logged data into a route profile (comprised of, in this case, a cleaning sequence); and reproducing/playing back the profiled route automatically using a control system.
Instructing or Teaching is an online operation whereby an operator may manually or remotely control the apparatus 100 and/or cleaning and track system 400 described herein through a PLC device. In exemplary embodiments, the PLC device may be any known PLC device that uses the IQAN electronic control system with a MD3 Module. PLC devices are standard in many industrial automation systems and used to synchronize overall system operation such that robot controller resources may be focused only on robot arm operation. The purpose of the instructing or teaching method is to allow an operator to define a cleaning route or sequence to be subsequently played back. The route may constitute an initial cleaning of an enclosed area including an arbitrary sequence of maneuvers positioning the apparatus 100 and/or cleaning and track system 400 for optimal cleaning purposes.
Under the next Route Profiling step, generally an offline activity, positioning data is derived from the sensor and positioning components attached to the MAAA 103 and/or track/drive system 414. Systems and apparatuses utilizing MAAAs and sensor and positioning components to derive positioning data are disclosed in U.S. Pat. Nos. 8,942,940, 8,997,362, and 8,965,571, which are incorporated herein by reference. Particularly, these patents disclose connected arm segments including at least one position transducer for producing a position signal, an electronic circuit for receiving the position signals from the transducer and for providing data corresponding to a position of a nozzle connected to the arm segments, and logic executable by the electronic circuit.
Once received from the sensor and positioning components, the positioning data is then logged to a log file on a processor in a computer or similar device for processing at a later point; the purpose being to define a route, for subsequent reproduction, by operating the MAAA 103 according to certain conditions. The computer may be located remotely at the control station or in another location near the area being cleaned. A log file may be a file on a mass storage device accessible by a computer processor attached and/or connected to the apparatus 100, containing time-stamped sensor readings that were recorded during the instructing/teaching run along the route. Particularly, raw data is compiled and processed to create a particular route profile configured to profile a particular enclosed area. In exemplary embodiments, the route profile includes information representing a cleaning sequence configured to assist in cleaning the enclosed area.
Once generated, the Route Profile is then implemented in the next step—Reproduction or Playback. Reproduction is an online method whereby the PLC device is configured to automatically reproduce or playback the cleaning sequence using the saved Route Profile, and also constantly monitor the sensor and positioning components. PLC device is configured to repeat the pre-programmed cleaning sequence by sending and receiving signals simultaneously.
Referring now to
In some embodiments, the PLC device 501 may bypass control of the EHFC device 502 by providing direct electrical signals to the track system and/or MAAA 503. In other embodiments, as shown in
Manual overrides 510 may be accomplished at any time during operation and programming of the cleaning sequence. Overrides 510 may occur through control of the PLC device 501 or the EHFC device 502. Overrides 510 may be accomplished by using control mechanisms located within a cabin/control station located remotely, which may then override automated controls of the PLC device. Overrides 510 may also be accomplished via manual valve control through a lever system within the EHFC device. Finally, these steps may be repeated until the desired optimal cleaning sequence is completed.
Referring now to
In the next step 602, once the sequence is implemented, the PLC device 501 begins to receive a signal from the sensor and positioning components 504, thereby allowing the PLC device 501 to send the correct signal to the EHFC device 502.
In the next step 603, the EHFC device 502 receives the signal from the PLC device 501, and then provides for resulting hydraulic, pneumatic and/or electrical flow to position the track system and/or MAAA 503 in an optimal cleaning position.
In the next step 604, track system and/or MAAA 503, produce the optimal cleaning motion for a pre-determined time period according to pre-programmed algorithms. This optimal cleaning motion includes smooth and consistent maneuvers of the track system and/or MAAA 503, and further limits useless, random, and wasted movement of the system by targeting a specific area for cleaning within an enclosed area. The specific time to clean an enclosed area or other surface may vary depending on several factors, including but not limited to the size of the area or surface to be cleaned and the amount of material to be cleaned. Embodiments of the present invention may provide for at least a 33% reduction in overall cleaning time compared to existing systems.
Finally, in step 605, if an area has been sufficiently cleaned, the cleaning process is completed and the track system and/or MAAA 503 may be removed from the area. However, if the area requires further cleaning, steps 602, 603, 604 for cleaning using the programmed cleaning and track system 400 and cleaning sequence may be repeated until the area has been fully cleaned. If additional areas require cleaning, the cleaning and track system 400 may be moved to those areas, and steps 601, 602, 603, 604 for cleaning may be repeated until the areas have been fully cleaned.
In embodiments of the present invention, a method of cleaning an area is provided. The method includes delivering/moving a cleaning apparatus 100 and/or cleaning and track system 400 as described herein to the area to be cleaned. Cleaning apparatus 100 and/or cleaning and track system 400 may be assembled within the area or may be assembled prior to being placed within the area. The method includes mounting the apparatus 100 and/or cleaning and track system 400 within or near the area. The method includes connecting the apparatus 100 to a high pressure fluid line, remotely operating the apparatus 100 to control a direction of flow from the high pressure fluid line, directing the flow of fluids towards material on a surface of the area to remove the material from the surface, and removing the fluids and material via a vacuum line. Once cleaning is complete, the apparatus 100 and/or cleaning and track system 400 may be removed from the area.
While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventions is not limited to them. Many variations, modifications, additions, and improvements are possible. Further still, any steps described herein may be carried out in any desired order, and any desired steps added or deleted.
This application claims the benefit of U.S. Provisional Patent Application No. 62/060,278, filed on Oct. 6, 2014, and 62/066,000, filed on Oct. 20, 2014, which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62066000 | Oct 2014 | US |
