Abstract:
A method of designing a driver&#39;s compartment for accommodating different driver&#39;s sizes, the compartment having a floor and a top end. The method includes: designing a driver&#39;s seat having a seat reference point (SRP) designating the position of a seat rear part and a seat pan height reference point (SPHRP) defining the position of the front portion of the seat. A seat moving mechanism moves the SRP vertically between a smallest position, where the SRP is at a vertical height H 1  from the top end, and a largest position where the SRP is at a vertical height H 2  from the top end, where H 2  is greater than H 1.  The vertical height H 3  of the SPHRP from the floor is maintained and constant. Front portion of the seat remains fixed. The top end is disposed at a vertical distance H 4  from the floor, where H 4  is the sum H 1  and H 3.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Israel Patent Application No. 207239 filed on 26 Jul. 2010, the contents of which are incorporated herein, in their entirety, by this reference. 
     TECHNICAL FIELD 
     The subject matter of the present application relates to a method of designing a driver&#39;s compartment for accommodating a predetermined range of driver&#39;s sizes comprising a smallest size and a largest size, and a movable driver&#39;s seat for the driver&#39;s compartment. 
     BACKGROUND 
     Economic and regulatory considerations cause designers to design driver&#39;s compartments of vehicles to accommodate drivers of a range of different sizes. This includes sizing a multitude of features of a vehicle&#39;s driver&#39;s compartment to suit both an upper end and lower end of the range. 
     An appreciation of the complexity of the features involved in merely positioning a driver in a driver&#39;s compartment can be received by review of known conventional driver&#39;s compartment designs shown in  FIGS. 1 and 2 . This design takes into consideration vertical and or horizontal distances of different body parts of the driver form various elements in the driver&#39;s compartment, for example, the distance between the head and the front window, the distance between the knees and the floor, etc. 
     Consequent to the need to suit a driver&#39;s compartment to drivers of different sizes, the size of a driver&#39;s compartment can be significantly larger than would be the case for a driver&#39;s compartment which is designed for only a driver of a single size. 
     SUMMARY 
     Throughout the present application, reference will be made to a driver&#39;s seat. 
     For the purposes of the specification and the claims, the term “driver&#39;s seat” includes the following features, described with reference to a seat generally designated as  10  in  FIGS. 3A and 3B : a base portion  12  and a back portion  14 ; the base portion comprising an upper surface  16 , the upper surface  16  having opposing front and rear edges ( 18 , 20 ) and side edges ( 22 , 24 ) extending therebetween; a Seat Reference Point (SRP) on the upper surface  16  of the base portion  12  being disposed equally spaced from the side edges ( 22 , 24 ) thereof and at an area of intersection of the back portion  14  and the upper surface  16 . 
     As will be understood, an SRP in the present application refers to a position of a part of a seat in a driver&#39;s compartment, and corresponds in meaning to that shown in FIG. 44 of MIL-STD-1472F, upon which  FIGS. 3A and 3B  are based. 
     Additionally, reference in the present application will be made to a Seat Pan Height Reference Point (SPHRP), which is a term that does not appear in MIL-STD-1472F, but is defined, with reference to  FIGS. 3A and 3B , as a point disposed on the front edge  18  of the upper surface  16  of the base portion  12 , the SPHRP being equally spaced from the side edges ( 22 ,  24 ). 
     In accordance with a first aspect of the subject matter of the present application, there is provided a method of designing a driver&#39;s compartment for accommodating a predetermined range of driver&#39;s sizes comprising a smallest size and a largest size, the compartment having a floor and a top end, the method including:
         a. designing a driver&#39;s seat having a seat reference point (SRP) used to define a position of a corresponding part of the seat in the compartment and a seat pan height reference point (SPHRP) used to define a position of the front portion of the seat in the compartment;   b. providing a seat moving mechanism configured to move at least the SRP vertically in the compartment between a first position in which the SRP is disposed at a first vertical distance H 1  from the top end and the SPHRP is disposed at a vertical distance of at least H 3  from the floor, and in which the seat is configured to accommodate a driver of the smallest size, and a second position in which the SRP is disposed at a second vertical distance H 2  from the top end, and the SPHRP is disposed at a vertical distance of at least H 3  from the floor, H 2  being greater than H 1  and in which the seat is configured to accommodate a driver of the largest size;   c. disposing the top end at a vertical distance H 4  from the floor, the distance H 4  corresponds to the sum of H 1  and H 3 , so that the vertical distance H 4  of the top end suits for accommodating the driver of the largest size is the seat only in the second portion.       

     The method above can enable a driver&#39;s compartment to be smaller than would be the case in the comparative examples shown in  FIGS. 1 and 2 , where the driver of the largest size is seen to sit at a height greater than a driver of a smaller size. An advantage of the method can be that a design of the driver&#39;s compartment can suit a range of sizes of drivers, by designing a seating position of a larger driver to be lower position than a smaller driver, which is larger than a range of sizes enabled with conventional seating positions, i.e. with the larger driver being seated higher up. 
     The method can further include limiting a vertical dimension of at least front window area of the compartment to suit the vision cone of the largest size driver in the second position. It will be appreciated that in some vehicles the material thereof having the highest areal density is the transparent material constituted by the vehicle&#39;s glass and/or transparent armor (for military vehicles). An advantage of reducing the window area of a driver&#39;s compartment can improve the mobility of the vehicle. According to one design, such method can allow a 100 mm change in height between the SRP of the largest and smallest driver to achieve a reduction of approximately 14% per meter squared of transparent material in a driver&#39;s compartment. 
     The method can further include designing the driver&#39;s seat to be movable by the seat moving mechanism into a number of additional positions between the first and second positions, the vertical distance of the SRP from the top end in the additional positions gradually increasing in the direction towards the second position.
         a. designing the seat moving mechanism to maintain a vertical distance of the SPHRP from the floor at a constant height or a height gradually decreasing in the direction towards the second position; and   b. designing the seat moving mechanism into a number of additional positions between the first and second positions, the vertical distance of the SRP from the top end in the additional positions gradually increasing in the direction towards the second position; a rate of increase of the vertical distance of the SRP from the top end in the additional positions in the direction towards the second position being greater than a rate of decrease of the vertical distance of the SPHRP from the floor in the additional positions in the direction towards the second position.       

     The method can further include configuring a front edge of a base portion to move only along a horizontal plane. The method can further include configuring an SPHRP to move only along a horizontal plane. An advantage of reducing the vertical dimension of the roof of a driver&#39;s compartment can improve the mobility of the vehicle. 
     Another advantage can be that such reduction can allow a more compact driver&#39;s compartment design than would otherwise be achievable in a military vehicle produced in accordance with the recommended clearances of Table XX of MIL-STD-1472F, shown below. 
     
       
         
               
             
               
               
               
             
           
               
                 TABLE XX 
               
               
                   
               
               
                 Recommended clearances around equipment operator&#39;s station to 
               
               
                 accommodate the 95th percentile soldier dressed in Aretic clothing. 
               
               
                 Operator seat in rear most position (FIG. 45) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 A. 
                 Elbow (dynamic) 
                 91 cm (36 in) 
               
               
                 B. 
                 Elbow (static) 
                 71 cm (28 in) 
               
               
                 C. 
                 Shoulder 
                 58 cm (23 in) 
               
               
                 D. 
                 Knee width (minimum) 
                 46 cm (18 in) 
               
               
                 E. 
                 Knee width (optimum) 
                 61 cm (24 in) 
               
               
                 F. 
                 Boot (provide adequate clearance to operate brake 
                 15 cm (6 in)  
               
               
                   
                 pedal without inadvertent acceleration operation) 
               
               
                 G. 
                 Pedals (minimum) 
                 5 cm (2 in) 
               
               
                 H. 
                 Boot (provide adequate clearance to operate 
                 15 cm (6 in)  
               
               
                   
                 accelerator without interference by brake pedal) 
               
               
                 1. 
                 Head (seat reference point (SRP) to roof line) 
                 107 cm (42 in)  
               
               
                 2. 
                 Abdominal (seat back to steering wheel) 
                 41 cm (16 in) 
               
               
                 3. 
                 Front of knee (seat back to manual controls on 
                 74 cm (29 in) 
               
               
                   
                 dash) 
               
               
                 4. 
                 Seat depth (seat reference point to front edge of 
                 41 cm (16 in) 
               
               
                   
                 seat pan) 
               
               
                 5. 
                 Thigh (under side of steering wheel to seat pan) 
                  24 cm (9.5 in) 
               
               
                 6. 
                 Seat pan height 
                 38 cm (15 in) 
               
               
                 7. 
                 Boot (front of seat pan to heel point of 
                 36 cm (14 in) 
               
               
                   
                 accelerator) 
               
               
                 8. 
                 Minimum mitten clearance around steering wheel 
                 8 cm (3 in) 
               
               
                 9. 
                 Knee-leg-thigh (brake/clutch pedals to lower edge 
                 66 cm (26 in) 
               
               
                   
                 of steering wheel) 
               
               
                   
               
             
          
         
       
     
     The method can include designing the driver&#39;s compartment to comply with any combination of the recommended clearances in the table above. 
     The top end, such as the compartment&#39;s ceiling can be limited in accordance with a specific ratio of the SRP. According to one example the method can include limiting a ratio of a vertical distance from the SRP to the floor and H 2  in the second position, to not exceed 330:1070. In such case the method can also include limiting a vertical dimension of the top end to suit the vertical distance of the SRP from the floor and a vertical distance from the SRP to the top end H 1 , in the first position of the smallest size driver, to not exceed 347:1053. According to another example, the method can further include limiting a ratio of a vertical distance from the SRP to the floor and H 2  in the second position, to not exceed 290:1070. In such case the method can also include limiting a vertical dimension of the top end to suit the vertical distance of the SRP from the floor and a vertical distance from the SRP to the top end H 1 , in the first position of the smallest size driver, to not exceed 347:1053. According to yet a further example, the method can including limiting a ratio of a vertical distance from the SRP to the floor and H 2  in the second position, to between 280:1070 and 290:1070. According to another example, the method can include limiting a ratio of a vertical distance from the SRP to the floor and H 2  in the second position, to not exceed 280:1020. In such case the method can also include limiting a vertical dimension of the top end to suit the vertical distance of the SRP from the floor and a vertical distance from the SRP to the top end H 1 , in the first position of the smallest size driver, to not exceed 347:953. 
     The method can further include limiting a ratio of the horizontal motion to vertical motion of the SRP to 2.8:1. 
     The method can further include designing the driver&#39;s compartment to be protected by armor. 
     In accordance with another aspect of the subject matter of the present application, there is provided a vehicle comprising a driver&#39;s compartment having a front window area, a driver&#39;s seat and a seat moving mechanism; the driver&#39;s seat having a seat reference point (SRP) used to define a position of a corresponding part of the seat in the compartment; the seat moving mechanism being configured to move the driver&#39;s seat into a number of positions, each different position including the SRP at a different horizontal distance from the front window area and a different vertical distance from the floor, each position having a horizontal distance the front window area which is greater than a different position having a vertical distance of the SRP from the floor smaller then the different position. 
     Such seat moving mechanism can have the advantage of overcoming a natural tendency of a driver to elevate the driver&#39;s seat to a maximum height in order to gain better vision. 
     The vehicle can further comprise a seat pan height reference point (SPHRP) used to define a position of a corresponding part of the seat in the compartment, the seat moving mechanism being configured to maintain a vertical distance of the SPHRP from the floor at a constant height. 
     The seat moving mechanism can be configured to move the SRP at a ratio of horizontal distance to vertical distance of 1:2.8. 
     The vehicle, driver&#39;s compartment, and driver&#39;s seat of the present aspect can have any combination of features described above in connection with the first aspect. 
     The vehicle can be an armored vehicle. 
     In accordance with either of the aspects above, the driver&#39;s compartment can be designed to be compliant with MIL-STD-1472F. Accordingly:
         a vertical distance from the SRP to the roof in the second position, i.e. a position designed for a largest driver size in the range, can be 1400 mm or less (item no. 1 of Table XX, the recommended clearance for the head);   the largest size in the predetermined range of driver&#39;s sizes can be a 95 th  percentile soldier, compliant with section 5.12.1 and Table XX of MIL-STD-1472F.   the smallest size in the predetermined range of driver&#39;s sizes can be a 5 th  percentile soldier compliant with section 5.12.1 of MIL-STD-1472F.       

     It will be understood that the specific examples given with respect to MIL-STD-1472F are for understanding of the various embodiments of the present invention. Therefore, should this standard be replaced in future with a subsequent updated standard having modified recommended clearances, the SRP, vertical distance from the SRP to the ceiling in the second position, largest size and smallest sizes in the predetermined range of driver&#39;s sizes can be designed in accordance with the updated standard, without departing from the subject matter of the present application. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to understand the subject matter of the present application and to see how it can be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic side view of a design of a known truck driver&#39;s compartment; 
         FIG. 2  is a schematic side view of a design of a known car driver&#39;s compartment; 
         FIG. 3A  is a schematic top view of a seat from FIG. 44 of MIL-STD 1472F with additional reference numerals added thereto; 
         FIG. 3B  is a schematic sectional side view of the seat in  FIG. 3A , also from FIG. 44 of MIL-STD 1472F with additional reference numerals added thereto; 
         FIG. 4  is a schematic side view of a driver&#39;s compartment designed to accommodate drivers of two different sizes; 
         FIG. 5A  is a schematic side view of a driver&#39;s compartment designed in accordance with the subject matter of the present application; 
         FIG. 5B  is a schematic side view of the driver&#39;s compartment in  FIG. 5A , with a modified driver&#39;s position; 
         FIG. 6  is a schematic representation of a side view of an SRP, SPHRP, and imaginary line connecting same, of a driver&#39;s seat in accordance with the subject matter of the present application, in different positions, the positions being spaced from each other for ease of explanation; 
         FIG. 7  is a schematic representation of some of the positions of the SRP, SPHRP, and imaginary line in  FIG. 6 ; and 
         FIG. 8  is a schematic side view of an example driver&#39;s seat. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout several views, there is shown in  FIG. 4  a driver&#39;s compartment generally designated as  30 . 
     The driver&#39;s compartment  30  comprises a top end, such as a ceiling  31  and a compartment floor  36 . The compartment  30  is designed to accommodate a larger driver  32  and a smaller driver  34  while being seated on a vehicle seat, generally designated  29 . It will be understood that in reality each driver is seated on a driver&#39;s seat  29  as defined above, however for the purposes of explanation, in the present view, the seat is shown in two different positions, a large driver position and a small driver position, with schematic lines  35 , and  37  representing a back portion of a seat in the large driver position, and in the small driver position, respectively. Similarly, SRP, SPHRP and imaginary lines  39  and  41  joining same are shown for both positions. The SRP for both positions is at approximately the same vertical distance (H 1 ) from the ceiling  31  of the driver&#39;s compartment  30 . In order to accommodate the two drivers, the SPHRP of the large driver position and the SPHRP of the small driver position are at different horizontal distances L 1  and L 2  from a front window area  38  of the driver&#39;s compartment  30 . The different horizontal distances L 1  and L 2 , are approximately 200 mm apart. 
     As a result of the different sizes of the small and large driver, the height of the compartment H 4 , must be designed to accommodate the seat with the larger driver  32  seated thereon, which is the sum of the height of the SPR and vertical distance H 1  from the ceiling. Thus, in order to accommodate large drivers a larger compartment is required, which in a case of an armored vehicle requires additional surface area to be protected. 
     In addition, as a result of their different sizes, each of the two drivers  32  and  34  have a vision cone ( 40 ,  42 ) which only partially overlaps the others vision cone. Areas of the vision cones which do not overlap are designated as  44  and  46 . As can be seen, the front window area of the driver&#39;s compartment is designed to have a vertical height HW 1  suited to accommodate both vision cones. Thus, the front window area is substantially large, which in the case of an armored vehicle requires additional window surface to be protected. 
     Referring now to  FIG. 5A , there is shown a driver&#39;s compartment  50  having a top end, such as a ceiling  51 , and a compartment floor  56 . The compartment  50  is designed to accommodate a larger driver  32  and a smaller driver  34 , while being seated on seat  55 . It can be seen that in the first position the driver&#39;s compartment  50 , can accommodate a small driver  34  while being seated on seat  55 , with the SPR 1  being at a vertical distance H 1  from the ceiling  51 . 
     In the second position, the driver&#39;s compartment  50 , can accommodate a large driver  34  by moving seat  55  to the second position in which SRP 2  of the seat  55  is lowered thereby increasing the vertical distance H 2  between the SRP 2  and the ceiling  51 . It is appreciated that the seat  55  can alternate between the first and the second position while maintaining the same horizontal distances (L 1 , L 2 ), from a front window area  39 . 
     As a result of this design, the height of the compartment H 4  can be smaller than the height of the compartment  30  of  FIG. 4 . This is due to the fact that SPR 2  in the large driver position is lower than the SPR 1 ′ in the small driver position, thus compensating for the difference between the vertical distance H 2  required in the large driver position and the vertical distance H 1  required in the small driver position. This allows minimizing the overall size of the compartment, thereby reducing the amount of surface area to be protected. 
     In addition, as can be seen in  FIG. 5A , the vision cone  40  of the larger driver  32  in this design encompasses a vision cone (not seen) of the smaller driver  34 . Thus, the front window area of the driver&#39;s compartment is designed to have a vertical height HW 2 , which is suited to accommodate both vision cones. The magnitude of HW 2  is smaller than the magnitude of HW 1  of  FIG. 4 . This design allows for a smaller surface area to be protected, and for providing a smaller protected window surface. Turning now to  FIG. 5B , it can be seen that the SPHRP of both positions can be maintained at a common vertical height from the floor  56 , and the seat can be adjusted merely by reducing the height of the SRP of the larger driver, while maintaining the same horizontal distances (L 1 , L 2 ), from a front window area  39 . Thus, a gradient of the imaginary line  59  between the SPHRP 2  and the SRP 2  of the seat position accommodating the larger driver  32  will have a larger magnitude than the imaginary line  61  between the SPHRP 1  and the SRP 1  of the seat position accommodating the smaller driver  34 . It is appreciated that maintaining the SPHRP in a fix vertical position for example at height H 3  from the floor  56 , allows for further minimizing the size of the compartment  50 . This is due to the fact that SPHRP according to some standard must be at a minimal height form the floor, for example, 380 mm, either for a small driver or for a large driver. Thus, providing a seat moving mechanism which is configured to move SRP in the compartment between the two vertical distances from the ceiling, while maintaining the SPHRP in a vertical distance of at least H 3  from the floor, allows for a small driver and a large driver to be accommodated in the compartment  50 , while meeting the requirement of the vehicle seat standard. However, according to another example, the seat moving mechanism can be configured to allow vertically moving SPHRP so long as a minimum vertical height of H 3  is maintained. 
     According to a further example, the seat in the compartment can be provided with a seat moving mechanism for vertically moving the SRP and SPHRP, as described hereinabove, while also allowing horizontally moving the seat. For ease of understanding of the vertical and horizontal movement of the SRP and SPHRP along a desired path, attention is directed to  FIG. 6 . 
     In  FIG. 6  a first position, generally designated as  60 A closest to a front window area of a driver&#39;s compartment (not shown) showing an SPHRP, designated as  61 A, an SRP, designated as  62 A, and an imaginary line joining same, designated as  63 A. 
     A second position is shown generally designated as  60 B, with the elements thereof having numerals corresponding to the numerals of the first position with the addition of the designation character “B”. Similarly third, fourth, fifth, sixth and seventh positions are shown. The final position is designated by the character G, which is the position of greatest horizontal distance from the front window area  39 . 
     Using X and Y coordinates, positions in millimeters, and assuming the following conditions: the SPHRP  61 A of the first position  60 A starts at position (0,380), each position is moved 33 mm in a horizontal direction away from the front window area, the internal height of the compartment is 1350 mm, and the length of the seat depth is 410 mm (item no. 4 in Table 1 above). Although the vertical positions of SPR and the SPHRP hereinabove were referred to with respect to the vertical distance from the ceiling, for the sake of clarity, the X coordinates here, are calculated as the vertical distance of SPR and the SPHRP with respect to the floor of the compartment. An example set of coordinates of the SPHRP and SRP for each position shown can be as follows: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Position 
                   
                   
               
               
                   
                 designation 
                 SPHRP 
                 SRP 
               
             
          
           
               
                 position 
                 suffix 
                 x 
                 y 
                 x 
                 y 
               
               
                   
               
             
          
           
               
                 1 
                 A 
                 0 
                 380 
                 408.44 
                 344.27 
               
               
                 2 
                 B 
                 33 
                 380 
                 407.36 
                 333.59 
               
               
                 3 
                 C 
                 66 
                 380 
                 406.01 
                 322.94 
               
               
                 4 
                 D 
                 99 
                 380 
                 404.38 
                 312.33 
               
               
                 5 
                 E 
                 132 
                 380 
                 402.47 
                 301.77 
               
               
                 6 
                 F 
                 165 
                 380 
                 400.28 
                 291.26 
               
               
                 7 
                 G 
                 198 
                 380 
                 397.82 
                 280.81 
               
               
                   
               
             
          
         
       
     
     It will be understood that the horizontal spacing between the positions in  FIG. 6  is exaggerated in the drawing to allow understanding of the pivoting motion. 
     A more accurate rendering of the horizontal spacing can be seen in  FIG. 7  where the first, second and third positions ( 60 A,  60 B,  60 C) are shown to demonstrate horizontal motion of the SRP and SPHRP. 
     Shown in  FIG. 8  is a driver&#39;s compartment, generally designated as  70 , of an armored vehicle (not shown). The driver&#39;s compartment  70  comprises a floor  71 , a roof,  73 , a front window area  72  comprising a window  79  made of transparent armor, a driver&#39;s seat  74  and a seat moving mechanism generally designated as  76 . 
     The driver&#39;s seat comprising a back portion  78 , base portion  80 , and having a seat reference point (SRP) used to define a position of a corresponding part of the seat in the compartment, and a seat pan height reference point (SPHRP). 
     The seat moving mechanism  76  comprising rails  78 , front legs  80  configured to slide along the rails  78  and pivotally attached to a front point  82  of the base portion  80 , compressible springs  84  configured to slide along the rails  78 , and a lever mechanism  86  pivotally attached at point  88  to the floor  71 . The lever mechanism  86  further comprising a locking mechanism (not shown) for locking the lever mechanism  86  in a desired position, or releasing it from that position. 
     In operation, when the locking mechanism  86  is not in a locked state, a user can slide the seat  74  in a horizontal direction, designated by arrow  90 , away from the front window area  72 , along the rails  78 . During this motion, the lever mechanism  86  pivots at the floor  71 , causing the seat  74  to pivot in the direction of arrow  92 , about front point  82 , compressing springs  84  toward the floor  71 , and moving the SRP away from the ceiling  73 . The user can then lock the seat  74  at the desired orientation, with the SRP of the seat consequently being at a vertical distance from the ceiling  73  larger than is the case when the seat is closer to the front window area  72 . In this position, compartment  70  can accommodate a larger driver. As will be understood, the seat  74  can be moved in a direction opposite to arrow  90 , in which case the seat will translate horizontally towards the front window area and pivot about front point  82  in a direction opposite to arrow  92 , thereby moving the SPR toward the ceiling and allowing a small driver to be seated on seat  74 , while maintaining the required vision cone. In any event, in both positions the SPHRP is not displaced toward the floor  71 , below a predetermined vertical distance, for example 380 mm. 
     Such seat can be used in a driver&#39;s compartment to achieve the positions described above. However, it will be understood that a seat design for carrying out the desired positioning described above can be carried out in numerous ways.