Patent Publication Number: US-2011068604-A1

Title: Drag Reducing System

Description:
RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 11/485,703, entitled: DRAG REDUCING SYSYEM, filed Jul. 13, 2006, now U.S. Pat. No. ______, which is related to and claims priority from U.S. Provisional Patent Application Ser. No. 60/699,219, entitled: DRAG REDUCING SYSTEM, filed Jul. 14, 2005, the entire disclosures of the aforementioned two patent applications are incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     The disclosed subject matter relates to drag reducing systems for vehicles, including drag reducing apparatus. 
     BACKGROUND 
     Fuel efficiency in trucks is highly dependent on drag. This is because when a truck travels at speeds of over seventy miles an hour, over sixty percent of its fuel is used in overcoming drag. For example, a modern Class 8 tractor-trailer truck can weigh up to 80,000 pounds, and have a drag coefficient of around 0.60 when traveling at the common United States (US) highway speed of seventy miles per hour (mph). At this speed, approximately sixty-five percent of the truck&#39;s fuel is expended for overcoming drag. 
     Various drag reducing mechanisms have been proposed. However, these drag reducing mechanisms exhibit drawbacks in that they are fixed to the vehicle and can not be moved during the time the vehicle is in motion, and are not controlled based on the location of the vehicle. 
     SUMMARY 
     The disclosed subject matter improves on the contemporary art by providing drag reducing mechanisms that decrease drag, whereby fuel efficiency is increased, resulting in cost savings for the truck owner. Additionally, increased fuel efficiency is environmentally beneficial. The disclosed subject matter also utilizes Global Positioning System (GPS) technology, and other satellite-based navigational technology to determine vehicular location. 
     There are disclosed vehicle drag reducing systems. The systems include, at least one drag reducing apparatus for moving between a first position, where the drag reducing apparatus is in an extended position, and a second position, where the drag reducing apparatus is in a retracted position; and, a mechanism coupled to the at least one drag reducing apparatus for moving the at least one drag reducing apparatus between the first position and the second position. There is also a navigation management system, for providing the location of the vehicle and the location of obstacles along the path of the vehicle; and, a processor, electronically coupled to the navigation management system. The processor is programmed to: analyze the location of the vehicle with respect to location of an obstacle along the path of the vehicle; and, signal the movement mechanism for moving the at least one drag reducing apparatus between the first and second positions in accordance with the location of the vehicle with respect to the location of at least one obstacle along the path of the vehicle. 
     Also disclosed is a drag reducing apparatus, for vehicles, typically trucks (for example, tractor-trailers), buses, cars, vans and the like. The apparatus includes, a first sheet including a first curved portion and a second curved portion; a second sheet including a first curved portion, substantially in alignment with the first curved portion of the first sheet, and a second curved portion, substantially in alignment with the second curved portion of the first sheet; and, the first sheet extends at least substantially along the length of the second sheet to define, a first end, a second end for the apparatus and an airflow pathway between the sheets, the air flow pathway between the first end an the second end. 
     Also disclosed is a method for controlling vehicle drag. The method includes, monitoring distances between a vehicle and at least one obstacle; determining a predetermined distance between the vehicle and the at least one obstacle; and, moving a drag reducing apparatus on the vehicle from a first extended position to a second retracted position, when the vehicle is within the predetermined distance. 
     Also disclosed is a vehicle drag reducing system. The system includes at least one drag reducing apparatus configured for placement on a vehicle. The at least one drag reducing apparatus is for moving between a first position, where the drag reducing apparatus is in an extended position, and a second position, where the drag reducing apparatus is in a retracted position. There is a mechanism operatively coupled with the at least one drag reducing apparatus for moving the at least one drag reducing apparatus between the first position and the second position. There is an apparatus for providing the location of the vehicle, for example, a Global Positioning System (GPS) receiver, at least one storage medium for storing a location of at least one obstacle. There is also a processor in electronic communication with the apparatus for providing the location of the vehicle, and in electronic communication with the at least one storage medium. The processor is programmed to: analyze the location of the vehicle with respect to location of the at least one obstacle; and, signal the movement mechanism for moving the at least one drag reducing apparatus between the first and second positions in accordance with the location of the vehicle with respect to the location of at least one obstacle. 
     Also disclosed is another vehicle drag reducing system. The system has at least one drag reducing apparatus configured for placement on a vehicle. The at least one drag reducing apparatus is for moving between a first position, where the drag reducing apparatus is in an extended position (typically above the height or roof of the vehicle), and a second position, where the drag reducing apparatus is in a retracted position (typically at or below the height or roof of the vehicle). There is also a mechanism operatively coupled with the at least one drag reducing apparatus for moving the at least one drag reducing apparatus between the first position and the second position. There is a Global Positioning System (GPS) apparatus for providing the location of the vehicle, and at least one storage medium for storing a location of at least one obstacle, and at least a first predetermined distance and a second predetermined distance. There is also a processor in electronic communication with the apparatus for providing the location of the vehicle, and in electronic communication with the storage medium. The processor is programmed to: analyze the distance between the location of the vehicle and the at the location of the at least one obstacle, and at least one predetermined distance; and, provide at least one signal that will cause the movement mechanism to move the at least one drag reducing apparatus between the first and second positions depending on the analyzed distance. 
     Disclosed is a method for controlling vehicle drag. the method includes, providing at least one drag reducing apparatus on a vehicle, the at least one drag reducing apparatus for moving between a first position, where the drag reducing apparatus is in an extended position, and a second position, where the drag reducing apparatus is in a retracted position. At least one database is maintained for storing a location of at least one obstacle, and the location of the vehicle is obtained, for example, by Global Positioning System (GPS) technology. The location of the vehicle with respect to the location of the at least one obstacle is analyzed; and, the at least one drag reducing apparatus is moved between the first and second positions in accordance with the location of the vehicle with respect to the location of at least one obstacle. 
     Disclosed is another method for controlling vehicle drag. The method includes, providing at least one drag reducing apparatus configured for placement on a vehicle, the at least one drag reducing apparatus for moving between a first position, where the drag reducing apparatus is in an extended position, and a second position, where the drag reducing apparatus is in a retracted position. At least one database is maintained, for storing a location of at least one obstacle, and at least a first predetermined distance and a second predetermined distance. The location of the vehicle is then determined by Global Positioning System (GPS) technology, and the distance between the location of the vehicle and the location of the at least one obstacle, and at least one predetermined distance is analyzed. The at least one drag reducing apparatus is moved between the first (extended) and second (retracted) positions depending on the analyzed distance. 
     There is disclosed a drag reducing apparatus for a tractor-trailer. The apparatus has a cap, having a rounded portion, for fitting on the trailer of the tractor-trailer, and a skirt unit. The skirt unit is for placement on the tractor of the tractor-trailer, and includes a first skirt and a second skirt. The second skirt is movable with respect to the first skirt, and includes an internal portion correspondingly configured to the shape of the rounded portion of the cap. The second skirt is movable between an extended position into proximity with the cap, for drag reducing, and a retracted position, out of proximity with the cap. 
     Also disclosed is a drag reducing apparatus. The apparatus has a body portion and a head portion, the head portion being movable between a retracted position and an extended position when increased drag reduction is desired. The body portion is formed of first and second airflow members. The first airflow member has a first curved sheet, and a second sheet, in substantial alignment with the first sheet, the second sheet including curvature corresponding to the curvature of the first sheet, the first sheet and second sheet spaced apart from each other to have a gap for airflow therebetween, and the first airflow member has a first end for air ingress and a second end for air egress. The second airflow member has a first curved sheet, and a second sheet, in substantial alignment with the first sheet, the second sheet including curvature corresponding to the curvature of the first sheet, the first sheet and second sheet spaced apart from each other to have a gap for airflow therebetween, and the second airflow member has a first end for air ingress and a second end for air egress. The first airflow member and the second airflow member are joined proximate their respective second ends. The head portion is movably attached to the first airflow member, and is movable in the first airflow member at least proximate to the first end, with the movement being between the retracted position and the extended position, where at least a portion of the head portion extends out of the first airflow member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Attention is now directed to the drawings, where like numerals and/or characters indicate corresponding or like components. In the drawings: 
         FIG. 1  is a diagram of an exemplary operation of the disclosed subject matter; 
         FIG. 2  is a top perspective view of a vehicle with a drag reducing apparatus in accordance with the vehicle of  FIG. 1 ; 
         FIG. 3  is a schematic diagram of a portion of the drag reducing system of  FIG. 1 ; 
         FIGS. 4 and 5  are diagrams of the exemplary operation of the embodiment of  FIG. 1 ; 
         FIG. 6  is a diagram of an exemplary operation of an alternate embodiment of  FIG. 1 ; and, 
         FIGS. 7A and 7B  are sectional views a drag reducing apparatus in accordance with embodiments of the disclosed subject matter; 
         FIGS. 8-10  are diagrams of an alternate embodiment in an exemplary operation; 
         FIG. 11  is a schematic diagram of a portion of an alternate drag reducing system; 
         FIG. 12A  is side view of an alternate drag reducing apparatus on a trailer of a truck in a retracted position, that is part of the alternate drag reducing system of  FIG. 11 ; 
         FIG. 12B  is a top view of the apparatus of  FIG. 12A  with the wing plates in the retracted position; 
         FIG. 12C  is side view of an alternate drag reducing apparatus on a trailer of a truck in an extended position; 
         FIG. 12D  is a top view of the apparatus of  FIG. 12B  with the wing plates in the extended position; 
         FIG. 12E  is a side cross sectional view of an opening taken along line  12 E- 12 E of  FIG. 12D ; 
         FIGS. 12F-12I  are side views of the a drag reducing apparatus of  FIG. 12A  being moved from an operative or active position to an inactive or storage position; 
         FIG. 13A  is a perspective view of a drag reducing apparatus in an extended position at the front end of a truck that is part of the alternate drag reducing system of  FIG. 11 ; 
         FIG. 13B  is a perspective view of the drag reducing apparatus of  FIG. 13A  in a partially extended position; 
         FIG. 13C  is a perspective view of the drag reducing apparatus of  FIG. 13A  in a retracted position; 
         FIG. 13D  is a top view of another drag reducing apparatus in an extended position at the front end of a truck that is part of the alternate drag reducing system of  FIG. 11 ; 
         FIG. 13E  is a cross sectional view of  FIG. 13D  taken along line  13 E- 13 E; 
         FIG. 13F  is a top view of the drag reducing apparatus of  FIGS. 13D and 13E  in a partially extended position; 
         FIG. 13G  is a cross sectional view of  FIG. 13F  taken along line  13 G- 13 G; 
         FIG. 13H  is a top view of the drag reducing apparatus of  FIGS. 13D and 13E  in a retracted position; 
         FIG. 13I  is a cross sectional view of  FIG. 13H  taken along line  13 I- 13 I; 
         FIG. 14A  is a side view of a drag reducing apparatus in an extended position along the tractor of a truck that is part of the alternate drag reducing system of  FIG. 11 ; 
         FIG. 14B  is a rear cross-sectional view of the drag reducing apparatus of  FIG. 14A , taken along line  14 B- 14 B; 
         FIG. 14C  is a side view of a drag reducing apparatus of  FIG. 14A  in a retracted position; and, 
         FIG. 14D  is a rear cross-sectional view of the drag reducing apparatus of  FIG. 14C , taken along line  14 D- 14 D. 
     
    
    
     DETAILED DESCRIPTION 
     There are disclosed systems and methods for reducing drag in vehicles, typically trucks, such as tractor-trailers, by moving drag reducing apparatus into and out of various positions, including those for maximizing drag reduction, in accordance with the location of the vehicle with respect to its distance both toward and away from an obstacle. 
     Throughout this document, directional references are made. These directional references, include, but are not limited to, upper, lower, front, rear, top bottom, and the like. These directional references are not intended to be limiting, but rather, are directed to typical orientations, for explanation of the disclosed subject matter. 
       FIG. 1  shows a vehicle, for example, a truck  20  (such as a tractor-trailer, with a tractor  20 ′ and a trailer  20 ″), traveling along a road, such as a highway (HW), for example the highway (HW) indicated as Highway  1 . The vehicle may also be, for example, a van, bus, automobile, trailer or other road going vehicle, and also trains, and nautical vessels, such as boats and ships. 
     The truck  20  includes a drag reducing system  21 , that includes a drag reducing apparatus  22 , moveable between an extended position ( FIG. 1  and  FIG. 2 ) and a retracted position, by a height adjustment mechanism  23 , that is electronically coupled or linked (by wired links, wireless links, or combinations thereof) with a master controller (MC)  24 . The master controller (MC)  24  is electronically coupled or linked (by wired links, wireless links, or combinations thereof) with a Global Positioning System (GPS) unit  25 . The movement between the extended position and the retracted position of the drag reducing apparatus  22  is necessary to avoid obstacles  26 , and similarly, movement from the retracted position to the extended position when the obstacle  26  has been safely cleared and drag reduction is to be resumed (or started). 
     Obstacles  26 , as used herein include, for example, bridges, tunnels, traffic signals (including those partially or completely overlying the roadway), signs and markers (including those partially or completely overhanging the roadway), overhanging cameras, wires, cables and lines, lights, trees, and the like. Obstacles  26 , as used herein, also include, road hazards, i.e., ditches, holes, oil slicks, trees, road curvature, changes in the number of lanes on a road, road narrowing and widening, road conditions (e.g., dirt, unpaved, paved and pavement type), road construction, and nature of the road (e.g., highway, interstate or rural, city or suburban street, the like), weather conditions (e.g., rain, wind, etc.) or other conditions or features of the road that may cause driving behavior to change. 
     The master controller (MC)  24  is in electronic communication with the GPS Unit (G)  25 , having an antenna  25   a . The master controller (MC)  24  and GPS unit (G)  25  are in electronic communication, by wired links, wireless links, or combinations thereof. The height adjustment mechanism  23  is also in electronic communication with the master controller (MC)  24  by wired links, wireless links or combinations thereof.  FIG. 3  shows a schematic diagram of the master controller (MC)  24 , GPS unit (G)  25 , and height adjustment mechanism  23 . 
     The GPS unit (G)  25  is such that it can provide the master controller (MC)  24  with location (position) information as to the truck  20 , and the location (position) of obstacles  26  (the obstacles as defined above). The GPS unit (G)  25  is also programmable to provide the master controller (MC)  24  with the distance between the truck  20  and the requisite obstacle  26 . The aforementioned information is typically provided to the master controller (MC)  24  by the GPS unit (G)  25  signaling the master controller (MC)  24 , or the master controller (MC)  24  polling (signaling) the GPS unit (G)  25  for this information or combinations thereof. The signaling by the GPS unit (G) and polling (signaling) by the master controller (MC)  24 , are typically in intervals, for example, one second apart. 
     The GPS unit (G)  25  is typically also programmed to detect predetermined distances between the truck  20  and the obstacle  26 , and determine if the truck  20  is within a predetermined distance toward or away from the obstacle  26 . The GPS unit (G)  25  signals the master controller (MC)  24  of this predetermined distance (the truck at or within this predetermined distance), for example, the distances D ( FIGS. 4-6 ) and V ( FIG. 6 ), detailed below. Similarly, the master controller (MC)  24  may poll the GPS unit (G)  25  for the aforementioned predetermined distances. The interaction between the master controller (MC)  24  and GPS unit (G)  25 , is in various operational modes, to generate data for activating the height adjustment mechanism  23 , these operational modes are detailed further below. 
     The height adjustment mechanism  23  is normally subject to control by the master controller (MC)  24 . The master controller (MC)  24  sends signals (by wired or wireless links, or combinations thereof), to the height adjustment mechanism  23 , to adjust the height of the drag reducing apparatus  22 , dependent on the location of the truck  20  with respect to an obstacle  26 . However, the height adjustment mechanism  23  is subject to manual control and manual override of the master controller (MC)  24  by the truck operator, to move the drag reducing apparatus  22  between the retracted and extended positions, and vice versa, and to maintain the retracted or extended positions, if necessary. The manual override, providing the aforementioned manual control, is indicated by indicated at  FIG. 3 , box  27 . The manual override can also be performed remotely, by a remote controller signaling a receiver in the manual controller  27 , to control the requisite components. 
     For example, when the drag reducing apparatus  22  is in the extended position, it is typically at a height (level or elevation) above the trailer  20 ″ of the truck  20 , and when in the refracted position, its height will be at least proximate to the height of the truck  20  (for example, the roof or top of the trailer  20 ″), as shown, for example in  FIG. 5 . Typically, in the refracted position, the drag reducing apparatus is at or below the height of the roof of the trailer  20 ″. 
     The location of the truck  20  is detectable by Global Positioning System (GPS) technology. This GPS technology includes satellites  32  in electronic communication with a GPS receiver  33 , the GPS receiver  33  part of a GPS unit (G)  25 , on the truck  20 . Global Positioning System (GPS) technology, including satellites and receivers, typical of satellites  32  and the receiver  33  in the GPS unit (G)  25 , is disclosed, for example, in Wikipedia—Global Positioning System, available at http://en.wikipedia.org/wiki/GPS, and attached hereto as Appendix A. 
     The master controller (MC)  24  is a computer or computer type device, programmed to activate the height adjustment mechanism  23 , for moving the drag reducing apparatus  22 , on the truck  20 . It includes a processor  24   a , for example, a Pentium® based processor(s), capable of running algorithms, programs and the like, and associated storage media  24   b , for storing databases and the like, and interfaces  24   c  suitable for interfacing with networks, including local area networks LANs, Wide Area Networks (WANs), including public networks such as the Internet, by wired or wireless links. There are typically sensors (S)  24   d  for monitoring the speed of the vehicle, electrically linked (by wired links, wireless links, or combinations thereof) to the processor  24   a . The master controller (MC)  24  also includes a transmitting and receiving unit (T/R)  24   e , for wired and wireless communications with the GPS unit (G)  25  and the height adjustment mechanism  23 . The master controller (MC)  24  is suitable to be updated by software downloads from CD&#39;s or other storage means as well as the Internet from a host server or the like, by wired links, wireless links or combinations thereof. 
     Exemplary databases in the master controller (MC)  24 , include, for example, databases for locations of obstacles (the obstacles defined above) as preprogrammed or downloaded into the database, as well as various predetermined distances, such as D, D′ and V, detailed below. The master controller (MC)  24  also runs analytical and comparison programs, as well as programs for locations of obstacles, determining the vehicle location with respect to predetermined distances where the drag reducing apparatus  22  is to be raised to the extended position, lowered to the retracted position, or maintained in the respective extended or retracted positions, identifying data and signals and sending data and signals to and from the GPS unit (G)  25 . The master controller (MC)  24  may also have hardware, software and the like for interfacing (interfaces  24   c ) with networks such as the Internet, or for receiving communications such as Bluetooth communications, in order to download software programs from locations on the Internet, compact discs (CDs) and other storage media, databases, updates thereto, and the like. These interfaces  24   c  may also be configured to receive data in real time. 
     The GPS unit (G)  25  includes the aforementioned GPS receiver  33 , that determines the location or position of the vehicle. This location data may be used to determine the speed of the vehicle, that is utilized by the GPS Unit (G)  25  and/or the master controller (MC)  24 , when speed is one of the parameters for the requisite application (such as secondary adjustment of the drag reducing apparatus  22  detailed below). The GPS unit (G)  25  is electronically coupled with a signaling unit or transmitter/receiver (T/R)  34 , for sending and receiving data, by signals (over wired and wireless links) or the like, to the master controller (MC)  24  on the truck  20  (the signals shown in broken lines in  FIG. 2 ). 
     The GPS unit (G)  25 , typically also includes, processors  35  and microprocessors, and the like, and other hardware and/or software for running programs, such as comparison programs, and for communication with other components on or associated with the drag reducing apparatus  22  and/or the truck  20 . There may also be sensors (S)  36  for monitoring the speed of the vehicle, electrically linked (by wired links, wireless links, or combinations thereof) to the processor  35 . There are also memory devices and hardware including storage media  37 , suitable for storing databases (DB), database information, and the like. The GPS unit (G)  25  also includes hardware, software and combinations thereof that serve as interfaces  38  for receiving data from networks, such as the Internet, Bluetooth communications, and the like. These interfaces  38  may also be configured to receive data in real time. 
     Exemplary databases include databases for locations of obstacles (the obstacles defined above) as preprogrammed or downloaded into the database, as well as various predetermined distances, such as D, D′ and V, detailed below. Exemplary applications include comparison programs, sending and receiving data and signals to or from the master controller (MC)  24  algorithms and the like. The GPS unit (G)  25 , including its databases, is typically programmed and updated by software downloads from CD&#39;s or other storage means as well as the Internet, by wired or wireless links. 
     For the predetermined distances, when the drag reducing apparatus  22  must be moved from the extended position to the retracted position when traveling toward an obstacle, and when the drag reducing apparatus  22  may be moved from the retracted position to the extended position, when the vehicle has safely cleared the obstacle moving away from the obstacle, for example, the respective distances D, D′ and V detailed above and below, these predetermined distances can be preprogrammed. They may also be programmed into the respective master controller (MC)  24  and GPS unit (G)  25  so as to be variable based on the detected speed of the vehicle (by any of the methods detailed above). They can also be determined dynamically and “on the fly” by algorithms (programmed into the master controller (MC)  24  and/or the GPS unit (G)  25  that utilize the detected speed and calculate the requisite time for changing the respective position of the drag reducing apparatus  22 . 
     The interaction between the master controller (MC)  24  and the GPS unit (G)  25 , to determine the position of the truck  20  with respect to the requisite obstacle  26 , and the determination of the position of the drag reducing apparatus  22 , should be maintained, or changed, from the extended position to the retracted position, or from the retracted position to the extended position, involving signaling the height adjustment mechanism  23  by the master controller (MC)  24 , is in accordance with the modes detailed below. While only a single mode need be in operation, typically multiple modes are in operation so as to be redundant, for safety purposes. 
     In a first exemplary mode, the GPS unit (G)  25  is programmed to detect the distance between the truck  20  and an obstacle  26 . The location of the truck  20  is determined by the GPS receiver  33  (and the satellites  32  and the antenna  25   a ), and the location of the obstacle  26  (obstacles being defined above) was programmed into and stored in the GPS unit (G)  25 . 
     The GPS unit (G)  25  is, for example, programmed to calculate the distance between the truck  20  and the obstacle  26 , and send a signal to the master controller (MC)  24 , when the truck  20  is within a predetermined distance from (both going toward and moving away from) the obstacle  26  (the predetermined distances programmed into the GPS unit (G)  25 . For example, the predetermined distance toward to obstacle may be the distances represented by D, as shown in  FIGS. 4-6  and detailed below, while a predetermined distance away from the obstacle  26  (a safe clearance distance) may be the distance represented by V, as shown in  FIG. 6 . 
     Once the master controller (MC)  24  receives this signal of the truck  20  being at or within a predetermined distance, it signals the height adjustment mechanism  23  to lower the drag reducing apparatus  22  to the retracted position. Similarly, once the master controller (MC)  24  receives a signal that the truck  20  is beyond a predetermined distance from the obstacle  26  (such that the obstacle  26  is cleared), it signals the height adjustment mechanism  23  to raise the drag reducing apparatus  22  to the extended position. 
     Alternately, the master controller (MC)  24  is programmable to recognize signals from the GPS Unit (G)  25 , when the truck  20  is at or within predetermined distances toward (for example, D), or away from (for example, V) the obstacle  26 , or outside of these predetermined distances. The GPS unit (G)  25  calculates the distance between the truck  20  and the obstacle  26  continuously, and at regular intervals, for example one second apart, and compares this distance to stored predetermined distances (for example, the distances D and V), and sends one or more signals to the master controller (MC)  24 , the signals corresponding to whether the truck  20  is at or within the predetermined distances (D or V). The signals are typically sent, from the GPS unit (G)  25  to the master controller (MC)  24  at regular intervals, for example, one second apart. 
     If outside of the predetermined distances, a signal is sent from the GPS unit (G) to the master controller (MC)  24 , that is recognized by the master controller (MC)  24  (that the truck  20  is outside of the predetermined distances D or V), that signals the height adjustment mechanism  23 , that the drag reducing apparatus  22  is to be moved (raised) or maintained (if already raised) in the extended position. Oppositely, if at or inside of the predetermined distances, a signal is sent from the GPS unit (G) to the master controller (MC)  24 , that is recognized by the master controller (MC)  24  (that the truck  20  is at or within the predetermined distances D or V), that signals the height adjustment mechanism  23 , that the drag reducing apparatus  22  is to be moved (lowered) or maintained (if already lowered) to the retracted position. 
     Alternately, the master controller (MC)  24  may poll (signal) the GPS unit (G)  25  for any of the aforementioned signals, and operate in accordance with the aforementioned mode for raising (moving to the extended position), and lowering (moving to the retracted position) the drag reducing apparatus  22 , as well as maintaining it in the retracted or extended position. Also alternately, the aforementioned mode can be operated by any combinations of signaling from the GPS unit (G)  25  to the master controller (MC)  24  or polling by the master controller (MC)  24  of the GPS unit (G)  25 . 
     In this first exemplary mode, the clearance distance (for example, distance V) is only considered cleared, whereby the master controller (MC)  24  signals the height adjustment mechanism  23  to move (raise) the drag reducing apparatus  22  to the extended position, when the truck is outside of the predetermined distance (for example, the distance D toward the obstacle  26 ). Otherwise, the GPS Unit (G)  25  and/or master controller (MC)  24  recognize the truck  20  as at or within the predetermined distance approaching the obstacle  26  (for example, the distance D), and function accordingly, to cause the master controller (MC)  24  to cause the height adjustment mechanism  23  to maintain the drag reducing apparatus  22  in the retracted position (or lower it to the retracted position, if for some reason it was in the extended position). 
     In a second exemplary mode, the GPS unit (G)  25  may be programmed to report (signal) vehicle (truck  20 ) position to the master controller (MC)  24 , as well as the location for the requisite obstacle  26  (stored in its database  37 ). This signaling is typically at regular intervals, for example, one second apart. 
     The master controller (MC)  24  calculates the distance between these two positions (locations) and compares it to preprogrammed or programmed predetermined distances (such as D and V) for signaling the height adjustment mechanism  23 , to raise, lower, or maintain the position of the drag reducing apparatus  22 , as detailed above. 
     For example, if the master controller (MC)  24  determines that the truck  20  is at or within the predetermined distance toward the obstacle  26 , for example, the distance represented by D, the master controller (MC)  24  signals the height adjustment mechanism  23  to move (lower) the drag reducing apparatus  22  to the retracted position. If the drag reducing apparatus  22  has been lowered to the retracted position, as long as the truck  20  remains within predetermined distances D or V, the master controller (MC)  24  will signal the height adjustment mechanism  23  to maintain the drag reducing apparatus  22  in the retracted position. Once the truck  20  is away from the obstacle  26 , outside the predetermined distance, for example, the distance represented by V, but not at or within the predetermined distance D, the master controller (MC)  24  signals the height adjustment mechanism  23  to move (raise) the drag reducing apparatus  22  to the extended position. If the drag reducing apparatus  22  has been raised to the extended position, as long as the truck  20  remains outside predetermined distances D or V, the master controller (MC)  24  will signal the height adjustment mechanism  23  to maintain the drag reducing apparatus  22  in the extended position. 
     In a third exemplary mode, the master controller (MC)  24  obtains the location of the vehicle (i.e., truck  20 ) by polling the GPS Unit (G)  25  for location of the vehicle, or by receiving signals from the GPS unit (G)  25 , as detailed above. The polling and signal sending are typically at regular intervals, for example, one second intervals. The master controller (MC)  24  then correlates this location to the location of the requisite obstacle  26 , based on the obstacle information in its database(s)  24   c , and determines the distance between the vehicle (i.e., truck  20 ) and the required obstacle  26 . 
     The master controller (MC)  24  having determined the distance between the truck  20  and the obstacle  26 , then determines if this distance is at or within any predetermined distances, where the drag reducing apparatus  22  is to be in the retracted position, such as, for example, distances D and V. The master controller (MC)  24  and height adjustment mechanism  23  then perform in accordance with the second exemplary mode, detailed above, to raise, lower and maintain the drag reducing structure  22 , in the respective extended and retracted positions. 
     While three exemplary modes have been described in detail above, this is exemplary only. Numerous other modes for calculating the distance between the vehicle and the obstacle, and comparing the calculated distance with a predetermined distance, this predetermined distance providing sufficient time, particularly for lowering the drag reducing apparatus  22  to the retracted position from the extended position, or for raising the drag reducing apparatus  22  from the retracted position to the extended position, are also possible. Other modes for maintaining the drag reducing apparatus  22  in the raised (extended) position or lowered (retracted) position, once moved to these respective positions, are also possible. 
     In all of the exemplary modes, as detailed above, the height (level) of the drag reducing apparatus  22 , when in the extended position, is further adjustable, in a secondary adjustment, based on the speed of the vehicle. The speed of the vehicle is detected, for example, by the GPS unit (G)  25  as detailed above, or through sensors or a speedometer reading, by the GPS unit (G) or the master controller (MC)  24 . When the speed is detected by the GPS unit (G)  25 , is obtained by the master controller (MC)  24  by either being signaled from the GPS unit (G)  25  or the master controller (MC)  24  polling the GPS unit (G)  25  for the speed (speed data). 
     By making this further or secondary adjustment (the master controller (MC)  24 , signaling the height adjustment mechanism  23  to adjust the drag reducing apparatus  22 ), drag reduction in the vehicle is enhanced. Vehicles traveling at higher speeds will have the drag reducing structure at a lower height or level (from the roof or other upper level, for example, the trunk of an automobile, or level from the retracted position of the vehicle), as compared the height or the level of the drag reducing apparatus  22  when the vehicle is traveling at lower speeds. 
     The actual heights or levels for the drag reducing apparatus  22  in accordance with the speed of the vehicle, when the drag reducing apparatus  22  is in the extended position, are programmed into the master controller (MC)  24  by any of the methods detailed above. For example, the level of the drag reducing apparatus  22  in the truck  20  traveling at 70 miles per hour (mph), will be lower than the level when the truck  20  is traveling at 50 mph, which will be lower than when the truck  20  is traveling at 35 mph. 
     An alternate secondary adjustment of the drag reducing apparatus can be made for atmospheric conditions such as temperature, pressure, etc., as detected by sensors for these conditions electrically linked to the master controller (MC)  24 . The master controller (MC)  24  can be programmed for example, such that a cold temperature will cause a lowering of the drag reducing apparatus  22  (from the height of the drag reducing apparatus  22  in the extended position), while a warmer temperature will cause a raising of the drag reducing apparatus  22  (from the height of the drag reducing apparatus  22  in the extended position). 
     One or more of the aforementioned secondary adjustments may be programmed into the master controller (MC)  24 . However, these secondary adjustments are optional, and need not be programmed into the master controller (MC)  24  for proper operation of the drag reducing apparatus  22 . 
     For example, turning also to  FIGS. 4-6 , a truck  20  is driving along Highway  1  (HW). Highway  1  has two obstacles, a bridge  44  and a tunnel  46 . Initially, the truck  20 , is at a distance greater than D from an obstacle  26 , and as such, at least a portion of the drag reducing apparatus  22  on the truck  20  is at an elevation above the truck  20 , in an extended position, serving to reduce drag on the truck  20 . 
     Once it is determined, by any one or more of the operative modes detailed above, that the truck  20  is at or within a distance D from the obstacle  26 , for example, the bridge  44 , as shown in  FIG. 4 , the master controller (MC)  24  signals the height adjustment mechanism  23  to move (lower) the drag reducing apparatus  22  to the retracted portion, as shown in  FIG. 5 . 
     This distance D is typically a distance that provides enough time for the height mechanism  23  to lower the drag reducing apparatus  22  to the retracted position, with the truck  20  traveling at normal highway speeds, approximately 55 to 70 mph. However, for safety, D is typically longer. This distance D, may be for example, approximately 1 to 4 miles. 
     As shown in  FIG. 5 , for example, the truck  20  is within the predetermined distance D from the obstacle  26 . This distance is continuously detected by the GPS Unit (G)  25 , and the master controller (MC)  24 , operating as detailed above, to maintain the drag reducing apparatus  22  in the retracted position. This signaling prevents the drag reducing apparatus  22 , now at a height less than height “h” (having been retracted in response to a signal from the master controller (MC)  24 ), from contacting the obstacle  26  of height “h” in  FIG. 3  (or being too close to the height of the obstacle), and causing damage to the obstacle and the truck  20 . 
     Turning to  FIG. 6 , similarly, when the truck  20  has cleared the obstacle  44  by a distance V (the distance V as preprogrammed into the GPS unit (G)  25  and/or the master controller (MC)  24 ), a second predetermined distance, and there is not another obstacle a distance approximately D (or an additional distance from D as programmed into the GPS Unit (G)  25  or the master controller (MC)  24 ) from the truck  20 , the master controller (MC)  24  will signal the height adjustment mechanism  23  to move the drag reducing apparatus  22  to the extended position, automatically. The distance V is typically less than the distance D, but could be equal to or greater than D, as programmed into the master controller (MC)  24  and/or GPS unit (G)  25 . 
     Additionally, as shown in  FIG. 6 , in a backup system, a transmitter (T)  50  or transmitters may be mounted on or proximate to an obstacle  26 , for example, the tunnel  46 . The transmitter (T)  50  sends a signal  52  detectable by the transmitting/receiving unit  37  of the GPS unit (G)  25  or the transmitting/receiving unit  24   d  of the master controller (MC)  24 . Additional transmitters, similar to the transmitter  50  may be placed in front of the transmitter(s)  50  on the highway or an obstacle  26 , if a further factor of safety is desired (extending the distance D′, as detailed below). 
     Should the truck  20  be at or within the predetermined distance, for example represented by D′(D′ being, for example, the range or distance of the signal  52  from the transmitter  50 ), with respect to the obstacle  46 , the GPS unit (G)  25  and the master controller (MC)  24  will operate in a mode to cause the master controller (MC)  24  to signal the height adjustment mechanism  23 . This signal(s) causes the height adjustment mechanism  23  to lower the drag reducing apparatus  22  on the truck  20  to the retracted position, (and maintain it in this refracted position, until the distance V is safely cleared), as detailed above. 
     The distance D′ is typically greater than the distance D, in order that the signal from the transmitter (T)  50  be received in proper time to move the drag reducing structure  22  to its retracted position, as the GPS Unit (G)  25  and/or master controller (MC)  24  are programmed to treat the distance D′ like the distance D (to cause the height adjustment mechanism  23  to move the drag reducing apparatus  22  to the retracted position). Alternately, this distance D′ could be equal to or less than the distance D, provided there is sufficient time for movement of the drag reducing structure  22  to its retracted position. 
       FIG. 7A  shows an exemplary drag reducing apparatus  22  for use on the truck  20 . The structure  22  includes two sheets  62 ,  63 , typically made of metal, polymers or the like. The sheets  62 ,  63  are arranged with respect to each other, such that the width (w 1 ) of the ingress opening  66  (through which air enters when in the extended position) between the sheets  62 ,  63  is greater than width (w 2 ) of the egress opening  67  (through which air exits when in the extended position) between the sheets  62 ,  63 . The sheets  62 ,  63  are held together by one or more spacers (not shown), attached by conventional mechanical fasteners and/or chemical fasteners, such as adhesives. 
     In a typical orientation, the sheet  62  is the top, upper or first sheet, while the sheet  63  is the bottom, lower or second sheet, defining a cavity  68  between the sheets  62 ,  63 . Air flow between the sheets  62 ,  63 , in the aforementioned typical orientation, is in accordance with the arrows  69 . 
     The sheets  62 ,  63  are typically “S” or serpentine shaped, with two arced portions  70 ,  71  (concave, as per the orientation of the sheets  62 ,  63  and airflow direction, shown here), and  72 ,  73  (convex, as per the orientation of the sheets  62 ,  63  and airflow direction, as shown here) common to both sheets  62 ,  63 , intermediate linear portions  74 ,  75 ,  76 ,  77 . Each sheet  62 ,  63 , has two radii of curvature. In the first, sheet  62 , the first arced portion  70  has a radius if curvature of r 1 , and the second arced portion  72  has a radius of curvature of r 2 . In the second sheet  63 , the first arced portion  71  has a radius of curvature of r 3 , and the second arced portion  73  has a radius of curvature of r 4 . These radii of curvature (r 1 -r 4 ) are related to each other by the following relation: 
       r 2 &lt;r 4 &lt;r 3 &lt;r 1    
     Additionally, the arced portions  70 ,  71 ,  72  and  73  extend through arcs of θ degrees, for example, approximately 85°. However, with the arcs of the arced portions  70 - 73 , one or more arcs may be the same and any of the arcs may be different from each other. 
     In an alternate embodiment of the deflecting structure  22 , the upper sheet  63  may include openings, single or multiple, to allow air flow out of the area between the upper  62  and lower  63  sheets as well as through the openings. These openings may be arranged in any number of ordered patterns or may be randomly positioned. These openings can be of a single or multiple sizes, and may be apertures or slots. 
       FIG. 7B  shows an alternate configuration  22 ′ of the drag reducing apparatus  22  of  FIG. 7A , similar to the drag reducing apparatus  22 , except where indicated. In this apparatus  22 ′, the upper sheet  62  is spaced evenly from the lower sheet  63  over the length of the entire drag reducing apparatus  22 ′. Four exemplary widths w 1 ′-w 4 ′ are shown, with w 1 ′ being the width at the ingress opening  66 , w 2 ′ being the width at the egress opening  67 , and, w 3 ′ and w 4 ′ being the widths at points intermediate the arcs. There are two major arcs, whose curvature is represented by φ and α. These arcs, φ and α, are typically different, with the arc represented by φ being, for example, approximately 85°, and the arc represented by a being, for example, approximately 67°. 
     Alternately, a drag reducing apparatus may only involve a single sheet. This single sheet could be any of the sheets or a portion of one of these sheets, such as a sheet from the apparatus  22  of  FIG. 7A  or the apparatus  22 ′ of  FIG. 7B , as detailed above. 
       FIGS. 8-10  show an alternate configuration of the master controller (MC)  24  and the GPS unit (G)  25 . Here, the master controller (MC)  24  and the GPS unit (G)  25  have been placed together for use in the tractor  20 ′ of the truck  20 . The master controller (MC)  24  (via a transmitter, not shown) sends signals (shown by the broken lines in  FIG. 8 ) to the height adjustment mechanism  23  (to a receiver therein, not shown) by wired links, wireless links, or combinations thereof. In this alternate configuration, the master controller (MC)  24  and GPS unit (G)  25  can be together as a single device, or separate, as multiple devices. Functioning of the components of this alternate configuration is the same as detailed above and shown in  FIGS. 1-6 . 
       FIG. 11  shows a schematic for an alternate system  110  for drag reduction in trucks and other vehicles. The system  110  is installed on trucks similar to that show in  FIGS. 1-7B  above, with the differences indicated below. The system  110  includes components identical to and similar to those for the schematic of  FIG. 3 , detailed above, with similar components indicated by primes (′) after the element number. These elements function similarly to these detailed above, with differences indicated below. The system also includes drag reducing apparatus  122 ,  322  and  422 . These drag reducing apparatus  122 ,  322 ,  422 , may be part of the system  110  alone or in any combination. 
     These drag reducing apparatus  122 ,  322 ,  422  are subject to control by a master controller (MC)  24 ′, and associated electronics and mechanical mechanisms for moving the drag reducing apparatus  122 ,  322 , and  422  between the retracted position and the extended position, when drag reduction is desired, similar to the retracted and extended positions detailed above for the system  21 . The master controller (MC)  24 ′ is similar to the master controller (MC)  24  detailed above, accept that it is connected to mechanisms for moving each of the drag reducing apparatus  122 ,  322 ,  422 , and is indicated accordingly. Coupled with the GPS unit (G)  25 , the master controller (MC)  24 ′ is operative in the modes for determining distances to and from an obstacle, and moving the drag reducing apparatus  122 ,  322 , and  422 , as detailed above. 
     The system  110  is such that any one, two or all of the drag reducing apparatus  122 ,  322  or  322 ′,  422  may be operative at any one time. The operativeness of any of the drag reduction apparatus  122 ,  322  or  322 ′,  422  is selected by the operator via a manual override in a manual controller  27 ′ (similar to the manual override of the manual controller  27  detailed above), that signals the master controller (MC)  24 ′ of the operative and activated drag reducing apparatus  122 ,  322  or  322 ′,  422 . 
     The master controller (MC)  24 ′ controls: motors  114 ,  115  for moving pistons  130 ,  178  to move the head portion  124  and wing plates  176   a ,  176   b , respectively on the drag reducing apparatus  122 , a drive mechanism  116 , for moving the drag reducing apparatus  122  between operative and active positions, and a storage position ( FIGS. 12G-12I ), a skirt movement mechanism  117  ( FIGS. 13A-13C ) for adjusting the positions of the skirts of drag reducing apparatus  322 , and, a panel movement mechanism  118 , for moving the pistons  428  associated with the lateral or side panels  424   a ,  424   b  on the tractor  20 ″ ( FIGS. 14A-14D ). The piston motors  114 ,  115 , drive mechanism  116 , skirt movement mechanism  117  and panel movement mechanism  118  are also subject to control of the manual controller  27 ′, as detailed below. 
       FIGS. 12A-12I  show an alternate drag reducing apparatus  122  for a vehicle, shown, for example, in use on a truck  20 . As shown in  FIG. 12A , the drag reducing apparatus  122  is formed of two portions, a head portion  124  and a body portion  126 . The head portion  124  is movable with respect to the body portion  126 , between a retracted position, as shown in  FIGS. 12A and 12B , and an extended position, as shown in  FIGS. 12C and 12D , when drag reduction is desired. The retracted and extended positions of the head portion  124  correspond to the extended and retracted positions for the entire drag reducing apparatus  122 . 
     When in the retracted position, the head portion  124  is typically within the body portion  126 , below the top height of the truck  20  (shown in broken lines in  FIGS. 12A and 12C ), and when in the extended position, the head portion  124  is aligned with the body portion  126 , and typically flush with the curvature of the body portion  126 . Although only one side of the trailer  20 ″ with the apparatus  122  is shown in  FIGS. 12A ,  12 C and  12 F- 12 I, the other side is symmetric and identical, whereby the following description applies to both sides of the trailer  20 ″ and the apparatus  122 . 
     The head portion  124  is typically curved, and “U” shaped in cross section. The head portion  124  is formed of by a central  128   a  and lateral portions  128   b . When in the extended position, the head portion  124  extends over the lower sheet  164   b  (this sheet  164   b  extending beyond the upper sheet  164   a  to the trailer  20 ″ or proximate thereto), forming a with a gap, typically rectangular in cross-section, for air ingress. The head portion  124 , when in the extended position, completes the curvature of the sheets  164   a  of the first member  164  of the body portion  126 , as the central portion  128   a  is flush with the upper sheets  164   a , of the body portion  126 . 
     The lateral portions  128   b  of the head portion  124  are bounded by the edges  170   a  of the front plates  170  (the front plates  170  extending beyond the lower sheet  164   b  in the area where the lower sheet  164   b  extends beyond the upper sheet  164   a ), as shown in  FIGS. 12B and 12D . The head portion  124  is, for example, joined to the body portion  126  by pistons  130  or other suitable driving mechanisms, with motors  114  ( FIG. 11 ), that attach to the head portion  124 , typically at the inner sides of the lateral portions  128   b . The motors  114  control the movement of the pistons  130 , and are linked to the master controller (MC)  24 ′ (by wired or wireless links, or combinations thereof), for moving the head portion  124  between the extended and retracted positions. 
     The head portion  124  is made of a sheet, for example, of metal, plastic or the like. The head portion  124  is typically closed, but the central portion  128   a  may include openings, similar to the openings detailed below for the sheets  164   a ,  164   b ,  165   a ,  165   b.    
     The body portion  126  includes paired sheets  164   a ,  164   b ,  165   a ,  165   b . The paired sheets  164   a ,  164   b ,  165   a ,  165   b  are typically “S” or serpentine shaped, similar in shape to those detailed in  FIGS. 7A and 7B  above. The first pair  164  (first sheet member) of sheets  164   a ,  164   b  is typically oriented as the upper pair, and is designed to align with the head portion  124 , while the second pair  165  (second sheet member) of sheets  165   a ,  165   b , is typically oriented as the lower pair. 
     The sheets  164   a ,  164   b ,  165   a ,  165   b  are typically formed of metal, plastic or the like, and are typically of similar configurations to each other, typically paralleling each other. The sheets  164   a ,  164   b ,  165   a ,  165   b  typically include plural openings  166 , such as slots or apertures, as shown in  FIGS. 12B and 12D . The slots and apertures are typically arranged in patterns, but can be arranged randomly. Also, the slots and apertures may be on any combination of the sheets  164   a ,  164   b ,  165   a ,  165   b , and on one or both sheet members  164 ,  165 . Typically, slots or apertures are positioned on the outer sheets  164   a ,  165   a  of the first  164  and second  165  members respectively. 
     The openings  166 , typically include rectangular slots, but can also include apertures, both the slots and apertures in shapes such as rectangular, polygonal, circular or rounded, triangular, or combinations thereof. The slots and apertures, or combinations thereof, are typically in patterns, but may be random. The slots or apertures may also be combined with inner  167   a  and outer  167   b  flanges, as shown in  FIG. 12E , either integral with the sheet or attached thereto by conventional fastening techniques. These inner  167   a  and outer  167   b  flanges enhance the air flow, shown by the arrows  168 . The inner flanges  167   a  may also be movable to close the openings under the control of the master controller (MC)  24 ′. The sheets  164   a ,  164   b  and  165   a  and  165   b  are typically joined by conventional fastening techniques. 
     There may also be a moveable cover sheet (not shown), to cover the slots and apertures when desired. This cover sheet may be a rollup sheet, at the junction of the members  164 ,  165 , under the control of the master controller (MC)  24 ′. It may also be manually controlled by the driver or remote operator. The slots or apertures may be covered or uncovered periodically, or moved between covered and uncovered at intervals (regular and staggered), that are typically programmed into the master controller (MC)  24 ′. 
     First or front plates  170  and second or rear plates  172 , these rear plates  172  are tapered inward from the point of attachment to the respective front plates  170 , join to the sheets  164   a ,  164   b  of the first pair  164 , and the sheets  165   a ,  165   b , of the second pair  165 . The joining is by conventional fastening techniques, such as welds, adhesives, mechanical fasteners and the like. The fastening is such that there is a gap between each pair of sheets  164   a ,  164   b  and  165   a ,  165   b , for airflow therethrough, to facilitate drag reduction. 
     Wing plates  176  are positioned laterally on the respective rear or second plates  172 . These wing plates  176  are movable from a retracted position, shown in  FIG. 12B , to an extended position, shown in  FIG. 12D , when drag reduction is desired. The retracted and extended positions of the head portion  124  correspond to the extended and retracted positions for the entire drag reducing apparatus  122 . 
     In the extended position, the wing plates  176  extend beyond the width of the tractor  20 ″, at an angle .beta., that may be, for example, approximately 25.degree. The wing plates  176  are typically hinged to the second or rear plates  172  and mounted by hinges  177  and moved by pistons  178  or the like, controlled by the master controller (MC)  24 ′. 
     The head portion  124  is typically coordinated with the wing plates  176 , via the master controller (MC)  24 ′. Accordingly, when the drag reducing apparatus  122  is in the retracted position ( FIGS. 12A and 12B ), the head portion  124  is within the body portion  126 , typically below the height of the trailer  20 ″ (illustrated by the broken line in  FIG. 12A ), and the wing plates  176  are against the second or rear plates  172  and within the width of the tractor  20 ″. Similarly, when the drag reducing apparatus  122  is in the extended position ( FIGS. 12C and 12D ), the head portion  124  is extended from and outside the body portion  126  (at least a portion thereof), for example, the edge  128   c  of the central portion  128   a  is above the height of the trailer  20 ″ (as shown in  FIG. 12C ), and the wing plates  176  are beyond the width of the tractor  20 ″. 
     The wing plates  176  may also be subjected to a secondary adjustment, once moved to the extended position. For example, if one of the obstacles programmed into the GPS unit (G)  25  and master controller (MC)  24 ′ is wind speed and wind direction, the wing plate  176  on the non-windy side of the trailer  20 ″ may remain open (in the extended position), while the wing plate  176  on the windy side of the trailer  20 ″ may be moved inward toward the rear plate  172 , partially or fully (to the retracted position), depending on the programming of the master controller (MC)  24 ′ for the various wind speeds. 
     The drag reducing apparatus  122  is movable between operative or active positions (shown in  FIGS. 12A-12E  and detailed above), when the truck  20  is moving or going to be moving, and storage positions,  FIGS. 12F-12I  (with  FIG. 12F  being a transitional position, between the operative or active positions and the storage position), when the truck  20  is parked (or otherwise stopped), to which attention is now directed. 
     The first or front plates  170 , typically include with bars  182  that are received in slots  184  on the sides of the trailer  20 ″ of the truck  20 . The bars  182  are on a drive mechanism (gear and chain under the control of a driver, not shown), the drive mechanism represented in the system  110  as element  116 , controlled by the master controller (MC)  24 ′, as shown in  FIG. 11 . The drive mechanism is also controllable through the manual controller  27 ′, as also shown in  FIG. 11 . The drive mechanism may be manual, such that the apparatus  122  can be moved into and out of the storage position manually (in accordance with the process and drawing figures detailed below). 
     As shown in  FIG. 12F , the drag reducing apparatus  122  is in an operative but transitional position, as the head portion  124  and wing plates  176  are in their retracted positions, and the drag reducing apparatus  122  has been activated to be moved to the storage position by the plates  170  being rotated (for example, clockwise) in the direction of the arrow  190 . 
     Movement to the storage position continues, as the first or front plates  170  are moved, typically under control of the master controller (MC)  24 ′ (as activated by the manual controller  27 ′) upward, or in a clockwise rotation (as per the arrow  191 ), and shown in  FIG. 12G , to a predetermined point, typically above the trailer  20 ″, as shown in  FIG. 12H . The apparatus  122  is then moved along the slots  184  (by the chain drive being activated), as per the arrow  192 , as shown in  FIG. 12H . As shown in  FIG. 12I , the apparatus  122  is now in the storage or inoperative position. 
     Should movement to the operative position be desired, the opposite of the above procedure is performed. The opposite direction is indicated by arrows  194  in  FIG. 12I ,  195 , in  FIG. 12H , and  196  in  FIG. 12G , ultimately ending in the transitional position of  FIG. 12F , where the active or operative positions may be resumed. 
       FIGS. 13A-13C  show another drag reducing apparatus  322 , for use at the front of the truck  20 , partially on the trailer  20 ′ and partially on the tractor  20 ″, and controlled by the master controller (MC)  24 ′. The drag reducing apparatus  322  is movable between extended positions, when drag reduction is desired, for example, on highways and other open roads, and a retracted position, when drag reduction is limited, due to the nature of the road, small road, open road with obstacles, or city or suburban street, or parking. 
     This drag reducing apparatus  322  includes a skirt unit  330 , typically a fixed skirt  332 , that receives and houses or covers (fully or partially) a movable skirt  334 , inside of it, in a telescoping manner. The movable skirt  334  typically includes a cut-out section  334   a , typically in an arc or rounded configuration, for example, partially cylindrical shaped. The movable skirt  334  is moved inward (as per the arrow  335   a ) and outward (as per the arrow  335   b ) to/from the fixed skirt  332  by pistons  336 , or other motors or the like, as controlled by the master controller (MC)  24 ′. The extent of the movement of the movable skirt  334  (to various distances outside of the fixed skirt  332 , typically to a point tangential to the arc of the cut-out section  334   a ), depends on the amount of drag reduction desired. 
     For example, when maximum drag reduction is desired, the movable skirt  334  is in its fully extended position, as shown in  FIG. 13A . This extended position corresponds to the extended position of the drag reducing apparatus  122  detailed above. Also, for example, when intermediate drag reduction is desired, the movable skirt is moved to a partially extended position, typically approximately half way out of the fixed skirt  332 , as shown in  FIG. 13B . This partially extended position corresponds to the extended position for the drag reducing apparatus  122  detailed above, as adjusted by the master controller (MC)  24 ′, based on the speed of the truck  20 , as well as the type of road curvature, as programmed into the GPS unit (G)  25  and the master controller (MC)  25 ′. If the speed of the truck and/or road curvature is within predetermined ranges, where the partially extended position is the proper position for the movable skirt  334 , the master controller (MC)  24 ′ will signal the movement mechanism to move the movable skirt  334  to this partially extended position. 
     As shown in  FIG. 13C , when drag reduction is not possible, the movable skirt  334  is within the fixed skirt  332 , in a retracted position. This retracted position corresponds to the retracted position for the drag reducing apparatus  122 , detailed above. 
     A cap member  340 , corresponding to the arc of the cut-out section  334   a , and for, example, typically of a radius of curvature, corresponding to the fifth wheel  342  (the point of attachment for the trailer  20 ″ to the tractor  20 ′ of the truck  20 ) of the truck  20 . Alternately, the cap member  340  may be on the tractor  20 ′, with the skirt member  330  on the trailer  20 ″. Also, alternately, the cap member  340  need not be present, whereby the cut-out portion  334   a  of the movable skirt  334  would not be present. 
     The fixed skirt  332  and movable skirt  324 , are for example, mounted on the tractor  20 ′ of the truck  20  and, with the movable skirt  334  attached to motor mechanisms (not shown), controlled by the master controller (MC)  24 . The fixed skirt  332  and movable skirt  334 , as well as the cap member  340  are typically unitary members. These skirts  332 ,  334  and the cap member  340  are typically made of rubber, plastic or the like. The cap member  340  may be fitted onto the trailer  20 ″ by either a friction fit and/or conventional mechanical fasteners. 
     Although shown as a single piece, that is moved inward and outward by motor mechanisms, the movable skirt  334  may be folded in an accordion like manner, for moving between the retracted and extended positions. This accordion like skirt is typically a unitary member, but may be in pieces, joined together by conventional fastening techniques. Alternately, the positions of the fixed skirt  332  and movable skirt  334  can be reversed, such that the movable skirt  334  rides over the fixed skirt  332 . 
     An alternate drag reducing apparatus  322 ′, similar to drag reducing apparatus  322  is shown in  FIGS. 13D-13I . Similar components bear the same numbers and have been discussed above, while different components are described below. This alternate drag reducing apparatus  322 ′ operates similar to the drag reducing apparatus  322 , detailed above.  FIGS. 13D and 13E  show the apparatus  322 ′ in a fully extended position, while  FIGS. 13F and 13G  show the apparatus  322 ′ in a partially extended position.  FIGS. 13H and 13I  shows the apparatus  322 ′ in a retracted position. 
     In the apparatus  322 ′ the cap member  340 ′ is a truncated partial sphere, whose radius of curvature, from the point RC in  FIG. 13E , is based on the location of the fifth wheel  342 . The movable skirt  334 ′ has a cut out section  334   a ′ or inner portion that is partially spherical, and typically includes a truncation, to correspond to the shape of the cap member  340 ′. 
       FIGS. 14A-14D  show another drag reducing apparatus  422 , for use at the sides of the trailer  20 ″ of the truck  20 . The drag reducing apparatus  422  is movable between an extended position, shown in  FIGS. 14A and 14B , when drag reduction is desired, for example, on highways and other open roads, and a retracted position, as shown in  FIGS. 14C and 14D , when drag reduction is limited, due to the nature of the road, small road, open road with obstacles, or city or suburban street, or parking. The extended and refracted positions for the drag reducing apparatus  422 , correspond to the extended and retracted positions for the drag reducing apparatus  122  detailed above. The adjustment in the extended position to a partially extended position performed, of the movable skirt  334  is controlled by the master controller (MC)  24 ′, depending on factors such as, the road curvature and road type, and speed of the vehicle, as programmed into or determined or obtained by either the master controller (MC)  24 ′ or the GPS unit (G)  25 . 
     The drag reducing apparatus  422 , includes panels  424   a ,  424   b , made of metal, plastic, or the like, and movably mounted, for example, by hinges  426  to the sides of the trailer  20 ″. These panels  424   a ,  424   b  are each moved between the extended (shown in  FIGS. 14A and 14B  as flush with the sides of the trailer  20 ″) and retracted positions by pistons  428  or other similar mechanisms. These extended positions may be such that the panels  424   a ,  424   b  extend beyond the width of the trailer  20 ″. The pistons  428  and their movement to control movement of the panels  424   a ,  424   b  are controlled by the master controller (MC)  24 ′. 
     In operation of the system  110 , for example, the operator, via the manual override of the manual controller  27 ′ selects the drag reducing apparatus  122 ,  322  or  322 ′,  422  that are active. The default setting is that all drag reducing apparatus  122 ,  322  or  322 ′,  422  are activated, if the manual override of the manual controller  27 ′ has not been accessed to deactivate one or more drag reducing apparatus  122 ,  322  or  322 ′,  422 . Also, as stated above, all drag reducing apparatus  122 ,  322  or  322 ′,  422  are movable between extended positions, when drag reduction is desired, and refracted positions, when drag reduction is not feasible, due to the presence of obstacles. 
     In this example operation, all drag reducing apparatus  122 ,  322  or  322 ′, and  422  are active and operable and operate similarly to drag reducing apparatus  22 , detailed above. As detailed above, the system  110  is operable in one or more of the three exemplary operative modes detailed above, with the height adjustment mechanism  23 , replaced by piston motors  114 ,  115 , skirt movement mechanism  117  and panel movement mechanism  118 . This allows the master controller (MC)  24 ′ to signal the piston motors  114 ,  115 , skirt movement mechanism  117 , and panel movement mechanism  118 , to move all three drag reducing apparatus  122 ,  322  or  322 ′, and  422 , typically in simultaneous or contemporaneous in time, between their retracted ( FIGS. 12A ,  12 B,  13 C or  13 H,  13 I,  14 C and  14 D), and extended positions ( FIGS. 12C ,  12 D,  13 A,  13 B or  13 D- 13 G,  14 A and  14 B), for drag reduction in their associated vehicles, such as the truck  20 . It should also be noted, that when the extended position of the skirted drag reducing apparatus  322  or  322 ′ is desired, the extent of skirt extension is determined based on factors such as truck speed and the requisite obstacles being approached or traveled on, as detailed above. 
     There have been shown and described preferred embodiments of a drag reducing system, and drag reducing apparatus, for vehicles. It is apparent to those skilled in the art, however, that many changes, variations, modifications, and other uses and applications for the apparatus and its components are possible, and also such changes, variations, modifications, and other uses and applications which do not depart from the spirit and scope of the disclosed subject matter are deemed to be covered by the invention, which is limited only by the claims which follow.