Patent Publication Number: US-11655098-B2

Title: Multipurpose relocatable structure and lifting systems and methods

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 17/214,063, filed Mar. 26, 2021, entitled, “MULTIPURPOSE RELOCATABLE STRUCTURE AND LIFTING SYSTEMS AND METHODS,” the disclosure of which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     Standardized shipping containers are commonly used throughout the world for shipping goods and cargo. These containers are referred to as ISO (International Organization for Standardization) containers, and intermodal freight containers, among other names. Shipping containers are typically configured in standard sizes, including 10 feet, 20 feet, and 40 feet in length. 
     Military use of containers is common and often a critical component of fast and efficient mobilization, as well as of sustained operations at deployed locations. There is a need for military, humanitarian, and other organizations to be able to ship equipment all over the world by sea, land, and rail, and to use these containers and the equipment within to set up mobile or temporary operations quickly and effectively. Military and commercial users have therefore adapted the ISO container for uses beyond storage. However, this design is limited by its dimensions, specialized lifting and moving requirements, and especially in the military context, the price of ISO-derivative designs. There is a need for a reasonably price mobile structure in a size between the ISO 10 and 20-foot container footprint that is pre-configurable for virtually any use and easily deployable. 
     Various embodiments of the present multipurpose relocatable structure and methods recognize and address the foregoing considerations, and others, of prior art devices. 
     SUMMARY 
     It should be appreciated that this Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to be used to limit the scope of the claimed subject matter. 
     According to one aspect of the disclosure, a multipurpose relocatable structure includes a floor system, a framework secured to the floor system, a ceiling pan, and walls secured to the framework. The framework includes a number of corner posts, a pair of upper end posts, a pair of upper side posts, a number of horizontal support members positioned between the corner posts, a number of vertical support members traversing the horizontal support members between the upper side posts and the floor system, and a number of ceiling supports positioned between the pair of upper side posts or the pair of upper end posts. The ceiling pan is secured to the ceiling supports. Each wall includes a number of panels, with each panel secured to at least one adjacent panel along a vertical edge. 
     According to another aspect, a multipurpose relocatable structure includes a floor system, a framework secured to the floor system, a ceiling pan secured to the framework, and walls secured to the framework. Each wall includes a number of panels. Each panel is secured to at least one adjacent panel along a vertical edge. A door is positioned in an end wall and includes an access hole sized to allow a person to egress through the access hole. An emergency escape hatch is positioned within the access hole of the door, the emergency escape hatch being releasable from an interior of the multipurpose relocatable structure and configured to be pushed outward to an exterior of the multipurpose relocatable structure after being released. A protected electrical connector is configured to receive an external electrical connector from an external power source and to provide electricity to an internal circuit breaker. The protected electrical connector is positioned within a wall between a plane defined by an external surface of the wall and the interior of the multipurpose relocatable structure. 
     According to yet another aspect of the disclosure, a multipurpose relocatable structure includes a framework secured to a floor system, a number of walls secured to the framework, and a protected electrical connector configured to receive an external electrical connector from an external power source and to provide electricity to an internal circuit breaker. The protected electrical connector is positioned within a wall between a plane defined by an external surface of the wall and the interior of the multipurpose relocatable structure. Each wall includes a number of panels. Each panel includes a first substantially vertical member, a first substantially horizontal member, a second substantially vertical member, and a second substantially horizontal member. The first substantially vertical member is positioned on a first edge of the panel and extends away from a substantially horizontal front face of the panel. The first substantially horizontal member extends toward a center of the panel from the first substantially vertical member to form a substantially L-shaped configuration. The second substantially vertical member is positioned on a second edge of the panel opposite the first edge and extends away from the substantially horizontal front face of the panel. The second substantially horizontal member extends away from the center of the panel from the second substantially vertical member to form a substantially backwards L-shaped configuration. The first edge of the panel is configured to nest within the second edge of an adjacent panel for coupling. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the invention will be described below. In the course of the description, reference will be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
         FIG.  1    is a front perspective view of a 12-foot standard version of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  2    is an exploded rear perspective view of a 12-foot standard version of a multipurpose relocatable structure according to various embodiments described below. 
         FIGS.  3 A,  3 B, and  3 C  show side, front, and rear views, respectively of a 12-foot standard version of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  4    is a cross-sectional view of the multipurpose relocatable structure of  FIG.  1    according to various embodiments described below. 
         FIG.  5 A  is a top view of a floor system of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  5 B  is a top view of a floor system, including a tread plate, of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  6    is a perspective view of a multipurpose relocatable structure without the walls and ceiling to show the framework according to various embodiments described below. 
         FIGS.  7 A and  7 B  show perspective and cross-sectional views, respectively, of a first wall panel configuration according to various embodiments described below. 
         FIGS.  8 A and  8 B  show perspective and cross-sectional views, respectively, of a second wall panel configuration according to various embodiments described below. 
         FIG.  9 A  is a perspective view of a shorty version of a multipurpose relocatable structure with side doors closed according to various embodiments described below. 
         FIG.  9 B  is a perspective view of a shorty version of a multipurpose relocatable structure with side doors open showing a battery charging build out according to various embodiments described below. 
         FIG.  9 C  is a perspective view of an interior of a shorty version of a multipurpose relocatable structure with side doors open showing a battery charging build out according to various embodiments described below. 
         FIG.  9 D  is a front view of an interior of a shorty version of a multipurpose relocatable structure with an end door open according to various embodiments described below. 
         FIG.  9 E  is a front view of a shorty version of a multipurpose relocatable structure with an end door closed according to various embodiments described below. 
         FIG.  9 F  is a rear view of a shorty version of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  10    is a front view of an emergency exit panel of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  11    is a rear perspective view of an emergency exit panel of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  12    is an exploded view of a door of a multipurpose relocatable structure showing an emergency exit panel according to various embodiments described below. 
         FIG.  13    is a rear perspective view of a multipurpose relocatable structure showing an environmental control unit (ECU) in an operational configuration according to various embodiments described below. 
         FIG.  14    is a close up view of an ECU from the interior of a multipurpose relocatable structure showing the ECU in the operational configuration according to various embodiments described below. 
         FIG.  15    is a close up view of an ECU from the exterior of a multipurpose relocatable structure showing the ECU in a transport configuration according to various embodiments described below. 
         FIG.  16    is a close up perspective view of a lifting corner of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  17    is a close up side view of a lifting corner of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  18 A  is a perspective view of a first face of a lifting corner of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  18 B  is a front view of a first face of a lifting corner of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  18 C  is a rear view of a first face of a lifting corner of a multipurpose relocatable structure according to various embodiments described below. 
         FIGS.  19 A and  19 B  are front and rear views, respectively, of a top face of a lifting corner of a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  20    is a front perspective view of a protected electrical connector on a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  21    is a rear perspective view of a protected electrical connector on a multipurpose relocatable structure according to various embodiments described below. 
         FIG.  22    is a rear perspective view of a protected electrical connector with a portion of a housing removed according to various embodiments described below. 
     
    
    
     DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS 
     Various embodiments now will be described more fully hereinafter with reference to the accompanying drawings. It should be understood that the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. 
     There is a need for military, humanitarian, and other organizations to efficiently establish mobile or temporary operations at deployed locations. This need is not adequately covered by conventional shipping containers, or structures designed within that footprint for the reasons articulated above. Other structures closer to the footprint of the subject structure likewise have characteristics that lessen their utility in comparison. Some conventional structures of near comparable size are not capable of being placed on the ground and must remain on the transport vehicle. Furthermore, the construction of those structures emphasizes lightweight characteristics and a less building-like structure, including a lower roof height. These characteristics impair its utility as a working space for maintenance and heavy storage and negatively impacts the utility as a building-like workspace. Furthermore, the honeycomb aluminum panels used in those structures are considered structural members. Any penetrations to the wall of the container can result in a compromise of a structural member, which requires that the container structure be deemed non-usable and non-deployable since the unit is not mission capable at the time of the damage. Given the complexity of the wall material, proper field repair can also be challenging. Even if the penetration is minor and has minimal to no effect on the structural capabilities of the container, the container may need to be shipped off station for repair. Doing so may significantly impact the mission capability of the affected military unit. 
     A specialized 12 foot structure fills this void, as it maximizes size without being too large to fit on internationally common transportation vehicles, and is capable of using common lifting equipment. This product is designed to be highly mobile and still retains many benefits of building-like functionality which offers a platform for multiple operational interior configurations. Interior configurations can be provided by the manufacturer as “turn-key” options and/or set up or modified by the customer using equipment on hand. 
     The multipurpose relocatable structure described herein can function like a robust building-like structure that offers turn key functionality either hooked up to an electrical source from a building, or to a generator, most anywhere in the world with minimal set up time. Due to its more expansive height and overall building-like design, the structure can function like a small facility for use as command, operations, communications, and mobile meeting spaces. Due to its heavyweight and more building-like design, it can be configured to accommodate the heavy equipment necessary for various mobile maintenance applications. Because it can be picked up and removed from the vehicle for operation, it can also house activities that due to hazards or other concerns need to be separated from permanent structures, or need to move around to supply the function in various locations for optimal efficiency. Its utility is equally broad in the civilian world, offering almost limitless options as a mobile structure in multiple fields from medical, construction, film, disaster relief, oil and gas exploration, industrial sitework or maintenance, to remote equipment and supplies housing and movement. 
     The multipurpose relocatable structures described herein include two primary structural configurations, although the interiors of both may be configured in any desirable manner to accommodate the intended mission of the structure. According to one embodiment, the multipurpose relocatable structure will be referred to as a 12-foot structure. One embodiment of the 12-foot structure includes dimensions that are approximately 82 inches wide, 96 inches high, and 144 inches long. According to another embodiment described in greater detail below, the multipurpose relocatable structure will be referred to as a 12-foot “shorty” structure. The shorty is approximately 82 inches wide, 88 inches high, and 144 inches long Generally, embodiments of the 12-foot structure include configuring the structure as a facility according to a particular purpose or mission. Because of the reduced height of the shorty structure, the shorty structure is particularly desirable when configured for equipment or material storage, or for a particular equipment purpose or mission (e.g., battery charging and storage). The shorty structure is sized for insertion into standard ISO containers (1EE or 1CC under the ISO 668 classification), for shipment, or may alternatively be shipped independently as they possess the structural components and associated capabilities with lifting corners, as described in detail below. Except where otherwise specified, the embodiments described herein are applicable to both the 12-foot and the shorty structure embodiments. 
     The multipurpose relocatable structure described herein is not configured to fit inside of a conventional size container (1EE or 1CC under the ISO 668 classification), although it is designed so it can fit into a high cube container (1AAA or 1BBB under the ISO 668 classification), or a flat rack for overseas transport. It is also capable of being transported by itself via any suitably sized and rated commercial motor vehicle, as well as train, with minimal preparation. It also has the dimensions to be moved by aircraft. Some buildouts can be operated still attached to a (parked) FMTV or commercial trailer without being disengaged. 
     The shorty multipurpose relocatable structure shares some of the design features of its larger cousin, but differs in its mobility options. Its width and height are the same, but it is shorter to accommodate shipment in a conventional 20 or 40 foot intermodal shipping container (1EE or 1CC under the ISO 668 classification). This product is generally not designed to be conditioned occupiable space (although it is still a structure that houses the equipment securely from the elements). It is also more of an industrial structure. It is hallmarked by a strong frame, multiple doors and easily accessible spaces. This product design can still facilitate a number of operational functions within the military (and the civilian side). Its dimensions allow it to be placed and carried inside of an ISO container anywhere in the world with very little expertise or equipment needed, other than a properly sized forklift. This feature also increases its utility as a mobile storage structure that can be removed from the container after shipment and immediately utilized as a self-contained, pre-organized room for whatever materials it stores. In addition, the specific dimensions of both versions of the structure fit the M35 series truck without alteration of the vehicle. Specifically, troop seats lining the bed of the truck need not be removed and stored, like with conventional designs. 
     Each version of this structure also has incorporated into its design four lift and tie down points, facilitating securing the structure for loading without the need for separate equipment or hardware (other than the chains or other tie downs). These same corner points are designed to facilitate the lifting and movement of the structure when all four points are used. Along with forklift pockets on multiple sides, the structure has built in two methods to move the structure when desired. 
     Utilizing the concepts and techniques described herein, a multipurpose relocatable structure provides a structure that is deployable via almost limitless types of vehicles using the same standardized hardware for securing the structure, lifting corners and forklift pockets that facilitate lifting and securing the structure without external components that are prone to damage, an infrastructure and wall panel configuration and dimensions that provides increased load capacity and building like functionality over structures of similar size, and an overall design and dimensions that facilitate much greater utility due to its operational interior options. 
     Turning now to  FIG.  1   , a multipurpose relocatable structure  100  is shown. According to one embodiment, the multipurpose relocatable structure  100  is a 12-foot multipurpose relocatable structure  102  (or 12-foot structure  102 ). According to another embodiment discussed briefly above and described in greater detail below with respect to  FIGS.  9 A- 9 F , the multipurpose relocatable structure  100  includes a 12-foot “shorty” structure. Generally, embodiments of the 12-foot structure  102  include configuring the structure as a facility according to a particular purpose or mission. Because of the reduced height of the shorty structure described below, the shorty structure is typically configured for equipment or material storage, or for a particular equipment purpose or mission (e.g., battery charging and storage). The shorty structure is sized for insertion into standard ISO containers for shipment, or may alternatively be shipped independently as they possess the structural components and associated capabilities with lifting corners, as described in detail below. Except where otherwise specified, the embodiments described herein are applicable to both the 12-foot and the shorty structure embodiments. 
     The multipurpose relocatable structure  100  includes walls  104  supported by a framework  106 , a floor system  108  (including a treadplate  112 ), and ceiling  110 . Lifting corners  114  provide a mechanism for lifting the 12-foot structure  102 , which can also be used to tie down or secure the 12-foot structure  102  in a vehicle. The multipurpose relocatable structure  100  is shown without an end door so that the interior may be seen. According to various embodiments, the 12-foot structure  102  may include one or more end doors positioned on a front side of the structure and/or one or more side doors positioned on one or more sides of the structure. These doors are shown and described below with respect to  FIGS.  3  and  9   . 
       FIG.  2    shows an exploded rear perspective view of the multipurpose relocatable structure  100 . The multipurpose relocatable structure  100  includes a framework  106  made up of a number of horizontal and vertical supports extending between larger corner and edge beams. The details of this framework  106  will be discussed in greater detail below with respect to  FIGS.  4  and  6   . Walls  104  are supported on the vertical portions of the framework  106 , with a ceiling pan  110  positioned on top. The ceiling pan  110  may be manufactured from a single piece of material, or may alternatively be manufactured from two or more ceiling panels that are secured adjacent to and abutting one another to create the ceiling pan  110 . To weatherproof the structure, the adjacent ceiling panels may be welded along a seam or otherwise sealed. The ceiling pan  110  is shown as a single piece of material, which is preferable to ensure weatherproofing. According to one embodiment, the ceiling pan  110  is manufactured from 10-gauge steel. Any suitable gauge metal may be utilized without departing from the scope of this disclosure, provided that it supplies sufficient structural support to meet or exceed the requirement that it withstand a snow load of approximately 40 lb/ft2 (200 kg/m2) and a personnel load of approximately 660 lb (300 kg) static over approximately 2 ft2 (0.2 m2). As seen in  FIG.  2   , the ceiling pan  110  may have corner notches  206  to accommodate the lifting corners  114 . 
     The walls  104  are made up of a number of parallel, adjacent panels  202 . The panels  202  are welded or otherwise secured to one another to form the walls  104  of appropriate dimensions to cover the vertical portions of the framework  106 . The framework  106  provides all of the structural support for the 12-foot structure  102  without the panels  202 . For this reason, and because the walls  103  are made up of panels  202 , any damage to or penetration of a wall  104  does not structurally impair the multipurpose relocatable structure  100  or require the multipurpose relocatable structure  100  to be shipped off station for repair as is required with conventional structures. Rather, if a wall  104  is penetrated and repair is desired, repair merely entails patching of a panel  202 , which can be done on-site. 
     Turning to  FIGS.  7 A- 8 B , two configurations of the panels  202  will now be described.  FIG.  7 A  shows a panel  202  according to a first configuration  702 . In this example, the panel  202  includes a front face  704 , a first side  706 , and a second side  708  opposite the first side.  FIG.  7 B  shows a cross section of the panel  202  of  FIG.  7 A . As seen in the cross section, the first side  706  and the second side  708  of this first configuration  702  each have a generally vertical member extending downward from the front face  704  and a generally horizontal member extending to the right from the generally vertical member to form a substantially “L-shaped” configuration. In doing so, the second side  708  of one panel  202  may nest within the first side  706  of an adjacent panel  202 , similar to a tongue and groove arrangement. The adjacent panels  202  may then be welded or otherwise fastened together, repeating the process for additional adjacent panels  202  until the wall  104  is complete. The interlocking configuration of the panels  202  increases the structural integrity of the multipurpose relocatable structure  100 , specifically providing improved capabilities to carry large compressive loads. 
       FIGS.  8 A and  8 B  show a panel  202  and cross-sectional view of the panel  202 , respectively, according to a second configuration  802 . In this example, the panel  202  includes a front face  804 , a first side  806 , and a second side  808  opposite the first side. As seen in the cross section of  FIG.  8 B , the first side  806  and the second side  808  of this second configuration  802  are mirror images of one another. Specifically, the first side  806  has a generally vertical member extending downward from the front face  804  and a generally horizontal member extending to the left from the generally vertical member to form a substantially backwards “L-shaped” configuration. The second side  808  has a generally vertical member extending downward from the front face  804  and a generally horizontal member extending to the right from the generally vertical member to form a substantially “L-shaped” configuration. In doing so, the vertically oriented members of the first and second sides of adjacent panels  202  may abut. The adjacent panels  202  may then be welded or otherwise fastened together, repeating the process for additional adjacent panels  202  until the wall  104  is complete. According to one embodiment, the panels  202  may comprise 14-gauge steel, although any suitable gauge or suitable material may be used without departing from the scope of this disclosure. 
     Returning now to  FIGS.  3 A- 3 C , a structure side  302 , a structure front  304 , and a structure rear  306 , respectively, of the multipurpose relocatable structure  100  will be discussed. The multipurpose relocatable structure  100  of  FIGS.  3 A- 3 C  may represent a 12-foot structure that may be configured as a facility with any type of internal configuration desired according to a designated mission for the structure.  FIG.  3 A  shows a structure side  302  according to one embodiment. The side view shows panels  202  coupled together to create the side wall. The floor system  108  can also be seen at the bottom of the structure. The floor system  108  may include forklift apertures  308  that facilitate movement of the multipurpose relocatable structure  100  by forklift. The structure side  302  shown in  FIG.  3 A  shows only one side. The multipurpose relocatable structure  100  has an opposite side that may be a mirror image or the structure side  302  that is shown in  FIG.  3 A . 
       FIG.  3 B  shows a structure front  304  according to one embodiment. The structure front  304  includes panels  202  that are coupled together to create a front wall adjacent to or around a door  310 . The door  310  includes a door latch  312  that is operative to selectively secure and unsecure the door  310  upon rotating the handle upwards and downward. And appropriate door latch  312  may be used without departing from the scope of this disclosure. The door  310  may include an emergency escape hatch  314 , which will be described in greater detail with respect to  FIGS.  10 - 12   . 
       FIG.  3 C  shows a structure rear  306  that according to this particular embodiment, has an environmental control unit (ECU) opening  204 . The ECU opening  204  is sized to receive an ECU for conditioning the air inside the structure. One or more rear upper panels  316  fill the space adjacent to or surrounding the ECU opening  204 . Panels  202  are coupled together to create a lower wall below the ECU opening  204 . It should be appreciated that the ECU opening  204  may be positioned at any location within the structure rear  306 , or alternatively within a structure side  302  or the structure front  304 . The floor system  108  may include forklift apertures  308  that are accessible from the structure rear  306  that facilitate movement of the multipurpose relocatable structure  100  by forklift. Various embodiments provide for forklift apertures  308  accessible from the structure front  304  and/or the structure rear  306 , as well as from the structure sides  302 . By doing so, the multipurpose relocatable structure  100  provides for easy loading and unloading to and from any type of vehicle and placement in the operating position at the deployed location. 
       FIG.  4    shows a cross-sectional view of a multipurpose relocatable structure  100  taken along lines  4 - 4  of  FIG.  1   . The cross-sectional view shows the framework  106  that provides the structural support for the multipurpose relocatable structure  100  and for mounting the panels  202  that create the walls  104 . The framework  106  includes a number of vertical support members  402  and a number of horizontal support members  404 . The number, spacing, and characteristics of the vertical and horizontal support members  402  and  404  may be determined according to the structural requirements of the multipurpose relocatable structure  100  to satisfy any given mission requirements. According to one embodiment, the vertical support members  402  and the horizontal support members  404  each comprise 14 gauge, 1.5 inch square steel tubing, with the horizontal support members  404  spaced approximately 20 inches apart. 
       FIG.  5 A  shows a top view of a floor system  108  without the treadplate  112  installed.  FIG.  5 B  shows the same view with the treadplate  112  installed. As seen in  FIG.  5 A , according to one embodiment, the floor system  108  includes side beams  502  and end beams  504  configured in a generally rectangular configuration. Side beams  502  and end beams  504  may be steel I-beams, or wide-flanged or W-beams. The floor system  108  additionally includes at least two tubes or conduits  506  with substantially rectangular cross-sections to provide the forklift apertures  308  for moving the multipurpose relocatable structure  100 . 
     While the term “forklift apertures” is used herein, it should be appreciated that the conduits  506  and corresponding apertures  308  may have any suitable cross-sectional shape configured to receive tines of a forklift or other corresponding portions of any type of transfer vehicle for engaging with the multipurpose relocatable structure  100  for lifting or relocation. The forklift apertures  308  are accessible through the side beams  502  via apertures cut or otherwise created in the side beams  502 . Alternatively, the side beams  502 , may be formed from three separate beam sections welded or coupled together to allow for the conduits  506  that create the forklift apertures  308 . According to other embodiments (e.g., as shown in  FIG.  3 C ), alternative or additional conduits  506  may be used to create forklift apertures  308  in the end beams  504  in the same manner as described above with respect to the forklift apertures  308  formed in the side beams  502 . 
     As seen in  FIG.  5 A , treadplate support members  508  (e.g., tubing manufactured from steel, other metal, polymer, and/or composite material) are arranged in parallel rows across the floor system  108 . The treadplate support members  508  are welded or otherwise coupled to side beams  502 . Perimeter treadplate support members  510  are similarly secured to the treadplate support members  508  and the side beams  502 . The treadplate support members  508  and the perimeter treadplate support members  510  provide support for the treadplate  112 . The number and orientation of the treadplate support members are not intended to limit the scope of this disclosure. Rather, any components or structural members may be used to support the treadplate  112 . According to one embodiment, the treadplate support members  508  comprise 1.5 inch square steel tubing, with the treadplate support members  508  spaced approximately 9.5-13 inches apart. The perimeter treadplate support members  510  may be generally “L-shaped” and manufactured from 14-gauge steel. 
       FIG.  5 B  shows the floor system  108  with the treadplate  112  in place on the treadplate support members  508  and the perimeter treadplate support members  510 . The treadplate  112  may be manufactured from a single plate of material, or in multiple plates  512  as shown in  FIG.  5 B . The treadplate  112  may be secured to the treadplate support members  508  and the perimeter treadplate support members  510  via welds, fasteners, or any suitable type of mechanism for permanently or removably mounting the treadplate  112 . According to one embodiment, the treadplate  112  is made from 10-gauge steel. 
       FIG.  6    is a rear perspective view of a multipurpose relocatable structure  100  without the walls and ceiling to show the framework  106  according to various embodiments. The framework includes corner posts  602 , upper end posts  604 , and upper side posts  606 . The corner posts  602 , upper end posts  604 , and upper side posts  606  are coupled together via welds or other fastening mechanisms at the lifting corners  114 . The corner posts  602  are secured to the floor system  108 , specifically to the side beams  502  and end beams  504 . According to one embodiment, the side beams  502  and end beams  504  are made from 5@16 wide flange steel. According to another embodiment, the side beams  502  and end beams  504  are made from 10-gauge, 4-inch square steel tubing. The tubing  610  surrounding the ECU opening  204  may be manufactured from 10-gauge, 3-inch square steel tubing. Ceiling supports  608  may be 14 gauge, 1.5 inch square steel tubing, spaced approximately 16 inches apart. 
       FIGS.  9 A- 9 F  show various views of a multipurpose relocatable structure  100  according to various embodiments. The multipurpose relocatable structure  100  of  FIGS.  9 A- 9 F  may be a shorty structure  902  as described above. In this example, the multipurpose relocatable structure  100  may be configured as a battery charging and maintenance structure. It should be appreciated that although the multipurpose relocatable structure  100  is shown and described as a battery charging and maintenance structure, the structures may be configured in virtually endless configurations according to the desired use. Such configurations include, but are not limited to, petroleum oil and lubricant storage and maintenance, glycol recycling and/or generation, milling and machining, fabrication and welding shop, small arms repair, hydraulic fabrication and repair, mobile water treatment, a mobile solar power facility, and a general maintenance facility. 
     In this example configuration, the multipurpose relocatable structure  100  has double side doors  310  in the side of the structure, as well as an end door  310  on one end of the structure. Any number and positioning of doors  310  may be used without departing from the scope of this disclosure. As shown in the interior views of  FIGS.  9 B and  9 C , the interior configuration  904  includes battery shelves and charging stations. The structure is configured with sufficient electrical power and corresponding connections suitable for the particular configuration, which in this example is for charging batteries. Any number and type of ventilation fans  906  may be mounted to the interior of the structure. Similarly, any number of vents  910  (as shown in  FIG.  9 F ) may be placed within one or more walls  104  of the structure to facilitate airflow and cooling through the interior.  FIG.  9 D  illustrates how panels  202  or other dividing mechanisms may be used to partition any portion of the interior of a structure as desired according to the specific implementation and needs of the structure. 
     According to various embodiments, the multipurpose relocatable structure  100  may include one or more emergency escape hatches  314  within one or more doors  310  or walls  104 .  FIGS.  10 - 12    show various views of an emergency escape hatch  314 .  FIG.  10    shows an emergency escape hatch  314  installed within a door  310 , as viewed from an interior of the multipurpose relocatable structure  100 . In this example, the emergency escape hatch  314  has four release handles  1004  that, when pulled toward the user, are operative to disengage from a reinforced border  1006  of the door  310 . After disengagement, the emergency escape hatch  314  may be pushed or kicked outward and through the door  310  to an exterior of the structure, providing an access hole  1010  (shown in  FIG.  12   ) through which persons may egress the structure.  FIG.  11    shows the emergency escape hatch  314  with the release handles  1004  pulled to disengage the corresponding latch mechanisms from the reinforced border  1006 . Any number and type of release handles  1004  may be used without departing from the scope of this disclosure. 
     As shown in  FIG.  11   , the emergency escape hatch  314  has an exterior panel that is larger than the opening through the door  314 , which results in an engagement surface  1008  that extends around the perimeter of the emergency escape hatch  314 .  FIG.  12    shows an exploded view of the door  314  and corresponding emergency escape hatch  314  and reinforced border  1006 . The engagement surface  1008  abutting a surface of the exterior of the door  310  prevents the emergency escape hatch  314  from traversing through the access hole  1010  into the interior of the structure. The latch mechanisms operatively coupled to the release handles  1004  abut and apply a force to the reinforced border  1006  when the release handles  1004  are in an engaged configuration adjacent to an interior surface of the escape hatch, preventing the emergency escape hatch  314  from traversing through the access hole  1010  to the exterior of the structure. However, when the release handles are pulled inward toward the interior of the structure, the corresponding latch mechanisms release the force applied to the reinforced border  1006  and move inward, allowing the emergency escape hatch  314  to traverse through the access hole  1010  to the exterior of the structure and providing access to the access hole  1010  for egress. 
     Turning now to  FIGS.  13 - 15   , various configurations of an ECU system  1302  of a multipurpose relocatable structure  100  will be described. The multipurpose relocatable structure  100 , and especially the shorty version, is configured to minimize any projection of components beyond an exterior plane of each wall, as defined by the lifting corners  114 . In doing so, the multipurpose relocatable structure  100  may be, placed in structures, transported, positioned abutting other structures and structures, and generally maneuvered without fear of damaging any components that project outward from the structure. One corresponding feature of the multipurpose relocatable structure  100  that maximizes the interior volume of the structure during use while minimizing the exterior footprint for transport includes the reconfigurable ECU system  1302 . 
       FIG.  13    is a rear perspective view of a multipurpose relocatable structure  100  showing an ECU system  1302  in an operational configuration. The ECU system  1302  includes an ECU that is slideable to extend substantially within the structure for transport, and to extend from the exterior wall  104  for operational use. In the operational configuration shown in  FIG.  13   , the ECU system  1302  extends outward from an exterior wall  104  such that the ECU system  1302  is substantially positioned on the outside of the structure while fluidly coupled to the interior. According to one embodiment, a protective cover  1304  may rotate upward to an open position in which the ECU system  1302  is substantially covered from above to protect from rain and the elements. When the ECU system  1302  is not present or in a transport configuration, the protective cover  1304  may be rotated downward to cover the ECU system  1302  or the aperture receiving the ECU system  1302 . The ECU system  1302  has an outer plate  1308  that has an inlet  1310  for receiving external air. The outer plate  1308  has an outer border  1306  that is sized to abut the wall  104  of the structure when positioned in the transport configuration. 
       FIG.  14    shows the ECU system  1302  from the interior of the structure when the ECU is configured in the operational configuration in which the ECU system  1302  projects outward from the exterior wall  104  as shown in  FIG.  13   . An inner plate  1402  abuts the inside surface of the wall  104 , which has bolts that extend through the inner plate  1402  to receive wingnuts  1410  for securing the ECU system  1302  in the operational configuration. Handles  1404  extend from the inner plate  1402  for gripping while reconfiguring the ECU system  1302  between operational and transport configurations. The inner plate  1402  has an outlet  1406  for routing conditioned air from the ECU system  1302  to the interior of the structure. Controls  1408  allow for the user to adjust the characteristics of the conditioned air from the ECU system  1302 . 
       FIG.  15    shows the ECU system  1302  from the exterior of the structure when the ECU is configured in the transport configuration. In this configuration, the ECU system  1302  is substantially positioned within the interior volume of the structure such that the outer plate  1308  abuts the outside of the wall  104  of the structure and is secured in place via wingnuts  1410 . In this transport configuration, the ECU system  1302  is substantially positioned within the structure and protected from damage. Any type of known rails or sliding mechanism may be used to facilitate movement between the operational and transport configurations, as well as to support the ECU system  1302  as it extends from a wall. 
     As discussed briefly above, the multipurpose relocatable structure  100  provides substantial lifting and tie down capabilities. Specifically, the lifting corners  114  of the multipurpose relocatable structure  100  provide a mechanism by which the multipurpose relocatable structure  100  may be readily attached to a crane or other lifting vehicle or device, or used as tie down anchors for securing the structure to a vehicle. According to one example, the lifting corners  114  are structurally robust enough to provide, along with the structural characteristics of the multipurpose relocatable structure  100  itself, a load capacity of approximately 8,250 pounds, with a safety factor of 3.2. These features significantly increase the lifting capacity of the multipurpose relocatable structure  100 . 
       FIGS.  16  and  17    show a close up perspective view and a side view, respectively, of a lifting corner  114 . According to this embodiment, the lifting corner  114  includes a first face  1604  and a second face  1606 . The first face  1604  is substantially parallel with a first plane defined by a first wall of the structure. The second face  1606  is substantially parallel with a second plane defined by a second wall of the structure that is adjacent to the first wall. For example, the first face  1604  may be facing an end wall of the structure and the second face  1606  is facing a side wall that is separated from the end wall by a corner post  602 . In this manner, the first face  1604  defines the first plane that is substantially normal to the second plane defined by the second face  1606 . According to one embodiment, the lifting corner  114  may include 3 pieces of ½ inch or other suitable steel, including a solid top face, the first face  1604 , and the second face  1606 . 
     Each of the first face  1604  and the second face  1606  includes a securement aperture  1602  that allows for a chain, hook, and/or other tie-down or lifting mechanism to pass through or to attach to.  FIGS.  18 A- 18 C  show perspective, front, and rear views, respectively, of a first face  1604  of a lifting corner  114  according to various embodiments. One with ordinary skill in the art would recognize that the second face  1606  comprises identical features, but configured for attachment to the first face  1604  and other components of the lifting corner  114  and structure as shown in the figures and described herein. 
     The first face  1604  includes a front edge  1802 , a top edge  1804 , a rear edge  1806 , a bottom edge  1808 , and a chamfered corner  1810 . The front edge  1802  is chamfered or angled to mate with a corresponding front edge of a second face  1606 . The front edge  1802  may be formed or cut with an approximately 45 degree angle so that when the two faces are mated, they form an approximately 90 degree angle around the corner of the structure. Similarly, the top edge  1804  may be chamfered to mate with a corresponding edge of a top face of the lifting corner  114 . The rear edge  1806  and the bottom edge  1808  may be chamfered as desired according to the weld or attachment mechanism to the upper end posts  604 , upper side posts  606 , and corner posts  602 . The chamfered corner  1810  may be chamfered or alternatively be substantially squared off. 
     The securement aperture  1602  provides a unique means for providing a lifting and tie-down mechanism for the structure. The securement aperture  1602  is defined by a first circular opening  1812  and a second circular opening  1814  connected by tangential cuts to create a front aperture edge  1816  and a rear aperture edge  1818 . Specifically, according to one embodiment, the radius of the first circular opening  1812  is two times the radius of the second circular opening  1814 . The circular openings are positioned to provide a front aperture edge  1816  that is substantially vertical. The rounded edges of the securement aperture  1602  distributes the stress and forces applied to the lifting corner  114 . The first circular opening  1812  is larger to receive and accommodate a hook, chain, and/or other lifting or securing device, while the second circular opening  1814  facilitates receipt and attachment of the lifting or securing device while minimizing the opening to maximize the strength of the lifting corner  114 . 
       FIGS.  19 A and  19 B  show front and rear views, respectively, of a top face  1900  of a lifting corner  114  of a multipurpose relocatable structure  100 . The front view would be visible from within the lifting corner  114  looking upward. The rear view would be visible from the top of the lifting corner  114  looking downward on the top face  1900 . The top face  1900  has a first face edge  1902  configured for coupling to the top edge  1804  of the first face  1604 . The top face  1900  has a second face edge  1904  configured for coupling to the top edge of the second face  1606 . A third edge  1906  and a fourth edge  1908  face the ceiling pan  110  and meet at a chamfered corner  1910 . 
     The configuration of the securement aperture  1602  allows for a chain or strap (e.g., a conventional ⅜ inch chain and corresponding hook) to be threaded through both securement apertures  1602  of a single lifting corner  114  and secured to itself. Alternatively, a hook or component on a chain or strap may be hooked into or otherwise attached to a securement aperture  1602  of a lifting corner  114 , particularly when tying the structure down to a vehicle. A chain or ratchet strap may also be secured to the bed of a vehicle, passed through the securement aperture  1602  in the first face  1604 , threaded out of the securement aperture  1602  of the second face  1606 , and secured to the bed of the vehicle. 
     According to one example, the front edge  1802  is approximately 5 inches in length and the top edge  1804  is approximately 5.15 inches in length. The center of the second circular opening  1814  is approximately 1.5 inches from the bottom edge  1808 , and the center of the first circular opening  1812  is approximately 1.5 inches above the center of the second circular opening  1814 . The first face  1604 , the second face  1606 , and the top face  1902  may each be manufactured from 0.5 inch steel plate. It should be appreciated that any suitable thicknesses and dimensions of the lifting corners  114  and corresponding components may be used without departing from the scope of this disclosure. 
       FIGS.  20 - 22    show various views of a protected electrical connector  1312  that is used to electrically connect the multipurpose relocatable structure and interior circuitry to an external power source, such as a generator or a power grid. According to one embodiment, the protected electrical connector  1312  is utilized with the shorty structure  902 . Conventional designs often include power inlets that include hardware that is mounted to the exterior of the structure. In doing so, the electrical connector projects outward from the wall of the structure, subjecting the connector to damage caused by impact with a vehicle or other structure during deployment. However, the protected electrical connector  1312  disclosed herein provides for a recessed connector that does not project outward from the wall  104 . Rather, as shown in  FIG.  20   , the protected electrical connector  1312  is positioned within a wall  104  between a plane defined by an external surface of the wall and an interior of the multipurpose relocatable structure  100 . The interface that mates with the external electrical connector from the power source is configured at an angle with respect to the plane defined by the external surface of the wall  104 . By angling the interface and recessing the protected electrical connector  1312 , the connector is protected from impact damage, yet accessible for quick and easy hook up and disconnect to and from an external power source. 
       FIG.  21    shows an interior view of the structure, showing a rear side  2100  of the protected electrical connector  1312 .  FIG.  22    shows the rear side  2100  of the protected electrical connector  1312  with a plate or portion  2100  of the connector housing removed to show the back side of the interface where electrical wires (not shown) route electricity from the external electrical connector through a wire conduit  2104  to a circuit breaker  2102 . 
     CONCLUSION 
     Many modifications and other embodiments of the disclosure will come to mind to one skilled in the art to which this disclosure pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. For example, as will be understood by one skilled in the relevant field in light of this disclosure, the embodiments may take form in a variety of different mechanical and operational configurations. Therefore, it is to be understood that the disclosure is not to be limited to the specific embodiments disclosed herein, and that the modifications and other embodiments are intended to be included within the scope of the appended exemplary concepts. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for the purposes of limitation.