Abstract:
To provide a swing device capable of making a user body sense a rising, lowering, and/or turning feeling more impressively or with higher reality with a simple structure, there is provided a swing device including: a swing member on which a user rides; a fulcrum support mechanism that swingably supports the swing member at a fulcrum; and a first driving mechanism that swingably supports a first driving point on the swing member and moving the first driving point in a vertical direction, the first driving point being spaced apart from the fulcrum in a longitudinal direction of the swing member, the fulcrum is placed on a rear side of a riding position of the user in the longitudinal direction of the swing member.

Description:
BACKGROUND  
       [0001]     1. Technical Field  
         [0002]     The present invention relates to a swing device in which a swing member on which a user rides is allowed to swing to thereby make the user sense a rising or lowering feeling and the like, and a control method therefor. To be specific, the present invention relates to a swing device with which a user can body sense a rising or lowering feeling that can be felt while a moving object such as an aircraft, a ship, a vehicle, or an animal is in a rising or lowering movement, and a control method therefor.  
         [0003]     2. Description of the Related Art  
         [0004]     Up to now, there is known a body-sensible swing game machine placed in an amusement facility such as a game arcade, in which a swing member on which a user rides is caused to swing according to an operation to an operation unit (see, for example, Japanese Utility Model Application Laid-open No. Hei 3-107993).  
         [0005]     In this game machine, in order to make the user body sense a attitude or a movement mode in a virtual space of a virtual moving object (e.g., fighter aircraft) whose moving mode in the virtual space is determined based on an operation by the user, there is employed a structure in which the swing member on which a seat, a steering rod, and the like are mounted is supported by a fulcrum placed on the front side of the seat and two driving points on the rear side of the seat, and the driving points are moved vertically, to thereby change a tilt angle of the swing member with respect to a horizontal plain.  
         [0006]     That is, in a case where an operation is performed to raise the moving object, both of the driving points are moved downward to tilt the swing member in a direction in which the user faces upward, thereby the user can body sense a rising feeling. In a case where an operation is performed to lower the moving object, both of the driving points are moved upward to tilt the swing member in a direction in which the user faces downward, thereby the user can body sense a lowering feeling.  
         [0007]     Further, in recent years, in order to make a user body sense a rising or lowering feeling more impressively or with higher reality, there is realized a game machine in which the number of driving points of a swing member is increased or the degree of freedom of driving directions of driving points is increased. However, increasing the number of the drive points or the degree of freedom of driving directions inevitably leads to a problem of increased size or cost of the machine.  
       BRIEF SUMMARY  
       [0008]     The embodiments of present invention address the above-mentioned problem and therefore it is an object of the present invention to provide a swing machine which is able to make a user body sense a rising or lowering and/or turning feeling more impressively or with higher reality with a simple structure  
         [0009]     Some embodiments of the present invention relate to a swing device including:  
         [0010]     a swing member on which a user rides;  
         [0011]     a fulcrum support mechanism for swingably supporting the swing member at a fulcrum; and  
         [0012]     a first driving mechanism that swingably supports the swing member at a first driving point thereof and drives the first driving point in a vertical direction (upward/downward direction), the first driving point being spaced apart from the fulcrum in a longitudinal direction (front/rear direction) of the swing member,  
         [0013]     wherein the fulcrum is placed on a rear side of a riding position of the user in the longitudinal direction of the swing member (first aspect).  
         [0014]     The inventors of the present invention have conducted extensive studies about the structures of the conventional game machines such as one disclosed in Japanese Utility Model Application Laid-open No. Hei 3-107993, and found the reason why it has been difficult to further enhance impression or heighten reality of the rising or lowering feeling, to thereby complete embodiments of the present invention.  
         [0015]     Hereinafter, the mechanism of embodiments of the present invention will be described in comparison with the conventional structure described in Japanese Utility Model Application Laid-open No. Hei 3-107993, by way of an example of a game machine  1  a plan view and a side view of which are shown in  FIGS. 1A and 1B .  
         [0016]     As shown in the figures, in the game machine  1 , an operation portion  3 , a display device  4  and a seat  5  on which a user O can sit are mounted on a swing member  2  swingably supported at two support points P 0  and P 1 . Based on an operation with respect to the operation portion  3 , a moving mode of a virtual moving object (e.g., fighter aircraft; hereinafter, sometimes simply referred to as moving object) in a virtual space is determined, and a video image of the moving object in the virtual space (or a video image of the virtual space drawn from a viewpoint of the moving object) is displayed on the display device  4 .  
         [0017]     Note that in a case where a rotation of the game machine  1  in a lateral direction (rotation about a line connecting the two support points P 0  and P 1 ) needs to be regulated or controlled, in addition to support mechanisms at the support points P 0  and P 1 , it is necessary to provide auxiliary means such as guide means for maintaining the level of the swing member  2  in the lateral direction.  
         [0018]     In the conventional structure, as shown in  FIG. 2A , the support point P 1  on a front side of a riding position of the user O serves as a fulcrum whose movement in a vertical direction is regulated, and the support point P 0  on the rear side of the riding position of the user O serves as a driving point which is moved in the vertical direction.  
         [0019]     Accordingly, in a case where an operation to raise the moving object is performed with respect to the operation portion  3 , in order to make the user O sense a rising feeling, the driving point P 0  is driven downward so as to tilt the swing member  2  in a direction in which the user faces upward as represented by a broken line of  FIG. 2A . In this case, the vertical position of the user O is lowered by an amount represented by reference symbol H. Thus, the user O senses a rising feeling because his/her body faces upward, and simultaneously senses a lowering feeling because his/her body is moved downward, which causes the result that the rising feeling, which is originally intended to be attained, is cancelled.  
         [0020]     The similar situation also occurs in a case where an operation is performed so as to lower the moving object. In order to make the user O sense a lowering feeling, the driving point P 0  is driven upward. Then, the swing member  2  tilts in a direction in which the user O faces downward, and at the same time, the vertical position of the user is heightened. Thus, the user senses a rising feeling as well as a lowering feeling, which causes the result that the lowering feeling, which is originally intended to be attained, is cancelled.  
         [0021]     In at least some embodiment of the present invention, the above-mentioned problems are solved by a constitution, as shown in  FIG. 2B , that the support point P 0  on the rear side of the riding position of the user O serves as the fulcrum whose movement in the vertical direction is regulated, and the support point P 1  apart from the fulcrum P 0  in a longitudinal direction (forward direction in the example shown in  FIG. 2B ) serves as a first driving point which is moved in the vertical direction.  
         [0022]     Accordingly, in a case where an operation to raise the moving object is performed with respect to the operation portion  3 , the first driving point P 1  on the front side is driven upward so as to tilt the swing member  2  in the direction in which the user O faces upward as represented by broken line of  FIG. 2B . In this case, the vertical position of the user O is heightened by an amount represented by reference symbol H. Thus, the user senses a rising feeling because his/her body faces upward, and simultaneously senses another rising feeling because his/her body is moved upward, thereby the synergistic effect of which significantly enhances impression or reality of the rising feeling.  
         [0023]     The similar situation also occurs in a case where the operation to lower the moving object is performed. The driving point P 1  on the front side is driven downward to tilt the swing member  2  in the direction in which the user O faces downward. In this case, the vertical position of the user is lowered. Thus, the user senses a lowering feeling because his/her body faces downward, and simultaneously senses another lowering feeling because his/her body is moved downward, thereby a synergistic effect of which significantly enhances impression or reality of the lowering feeling.  
         [0024]     The effects of the embodiments of the present invention are attained by changing the tilt angle of the swing member  2  by rotating the swing member  2  about the fulcrum P 0  placed at the rear side of the riding position of the user O and therefore, the vertical movement of the fulcrum P 0  needs to be regulated to a certain extent. However, note that a structure can also be employed in which the fulcrum P 0  moves vertically by an amount in a range sufficiently small with respect to the vertical movement of the first driving point P 1 .  
         [0025]     Likewise, it is sufficient if the first driving point P 1  in the swing device is spaced apart from the fulcrum P 0  by a predetermined amount in the longitudinal direction. Therefore, even in a case where the first driving point P 1  is placed on the rear side of the fulcrum P 0  as shown in  FIG. 2C , the effects of the embodiments of the present invention can also be attained by the mechanism similar to that explained with respect to  FIG. 2B . Note that from a viewpoint of a space efficiency or the like, it is preferable that the first driving point P 1  be placed on the front side of the fulcrum P 0 , especially on the front side of the riding position of the user as shown in  FIG. 2B .  
         [0026]     The swing device of the present invention can be used for the body-sensible game machine  1  with which the user steers the virtual moving object while enjoying such a feeling that the user actually rides on the moving object. In addition, the swing device of the present invention can also be used for a body-sensible video image appreciation device with which a user watches a video image from a viewpoint of a moving object while enjoying a feeling that the user actually rides on the moving object. As such, the swing device of the present invention can be applied to various devices which are intended to make a user body sense a rising feeling, a lowering feeling, or the like.  
         [0027]     The swing member should have a strength and a size that allows the user to ride on, and a shape thereof may be a plate-like shape as shown in  FIGS. 1A, 1B  and  2 A to  2 C. Alternatively, the shape may be a three-dimensional shape such as a shape of a fighter aircraft or a shape of a cockpit thereof.  
         [0028]     The fulcrum support mechanism and the first driving mechanism swingably support the swing member. Examples of the support mechanism suitable for swingably supporting the swing member include a universal joint and a ball joint.  
         [0029]     Any variety of mechanisms capable of driving the first driving point P 1  in a vertical direction, such as an oil hydraulic cylinder, can be employed as the first driving mechanism. A linear actuator excellent in a driving length, driving velocity, driving force, and so on, is particularly preferably employed.  
         [0030]     Note that, from a viewpoint of enhancing a transfer efficiency of the driving force, it is most preferable that, assuming a virtual sphere whose center corresponds to the fulcrum P 0  and radius corresponds to a line segment connecting the fulcrum P 0  and the first driving point P 1 , the driving force be applied in a tangential direction with respect to the sphere. However, in a case where a driving direction by the first driving mechanism is made always orthogonal to the line segment connecting the fulcrum P 0  and the first driving point P 1 , the angle formed by a driving direction of the first driving mechanism and the above-mentioned line segment changes as the first driving point P 1  moves on a surface of the sphere whose radius corresponds to the line segment. Therefore, a mechanism, such as a cylinder, which performs linear movement cannot constantly perform tangential movement to the sphere surface in reality.  
         [0031]     Accordingly, in the case where the first driving mechanism is one for performing the linear movement, it is preferable that an operational direction of a supporting force by the first driving mechanism is orthogonal to the line connecting the fulcrum P 0  and the first driving point P 1  in a reference state (e.g., a state of starting or finishing a game in the embodiment to be described later, or a state where the moving object is in level flight in the virtual space).  
         [0032]     In some embodiments of the present invention, the riding position refers to a position of the user on the swing member in the operational state, i.e., while the first driving point is driven by the first driving mechanism. For example, in the case of the structure in which the user sits on the seat of the swing member in the operational state, the riding position corresponds to the position of the seat. Although, a case where the user sits on the seat is exemplified in this example, the seat is not always necessarily provided to realize the present application. For example, in a case where retention mechanism or anti-drop means for preventing a user standing upright from dropping from the swing member is provided, the seat is not necessarily provided.  
         [0033]     In the specification of the present invention, the terms indicating the directions of forward, backward, left, and right are used based on which direction the user faces in the operational state, that is, while the first driving point is driven by the first driving mechanism. The forward direction refers to the direction that the user faces, the backward direction refers to a reverse direction thereof, and the left and right directions indicate the directions orthogonal to the front and rear directions in the horizontal plane.  
         [0034]     Various embodiments of the present invention preferably relates to a swing device further including:  
         [0035]     a second driving mechanism that swingably supports the swing member at a second driving point thereof and drives the second driving point in a vertical direction independently from the first driving mechanism, the second driving point being spaced apart from the fulcrum in a longitudinal direction of the swing member, and being spaced apart from the first driving point in a lateral direction of the swing member (second aspect).  
         [0036]     That is, in addition to the structure of the first aspect of the present invention, the second aspect of the present invention is characterized by including the second driving mechanism for driving the second driving point in the vertical direction, the second driving point spaced apart from the fulcrum in the longitudinal direction and spaced apart from the first drive means in the lateral direction.  
         [0037]     Accordingly, in the second aspect of the present invention, by raising or lowering the first and second driving points simultaneously, similarly to the first aspect of the present invention, it is possible to make the user body sense a rising/lowering feeling. In addition, by vertically driving the first and second driving points in a manner that the their heights are different to each other, it is also possible to make the user body sense a turning feeling to the left or right of the virtual moving object moving in the virtual space, or a combined feeling of a turning feeling to the left or right and a rising/lowering feeling thereof.  
         [0038]     In various embodiments of the present invention, it is preferable that the swing device further include:  
         [0039]     a support shaft projecting between the first driving point and the second driving point; and  
         [0040]     static determinate maintaining mechanism having a guide hole defined therein through which the support shaft is rotatably inserted, for regulating movement of the support shaft in the lateral direction of the swing member, and guiding the support shaft in the vertical direction (third aspect).  
         [0041]     In the third aspect of the present invention, a line connecting the fulcrum and the support shaft serves as an axial center of the swing member and the degree of freedom of the movement of the swing member is limited to the raising and lowering movement of the axial center along the guide hole and the rotational movement of the swing member about the axial center. Thus, it becomes possible to readily maintain static determinate of the swing member. It is particularly preferable that the support shaft be positioned such that the distances therefrom to the first and second driving points are the same.  
         [0042]     In some aspects of the present invention, it is preferable that the driving point is placed on a front side of the riding position of the user in the longitudinal direction of the swing member (fourth aspect).  
         [0043]     That is, assuming that driving mechanisms of identical performances are used, the larger the distance between the fulcrum position and the driving points are, the lower power (lower torque) the movement can be performed with. However, since the fulcrum is placed on the rear side of the seat of the user in the first and second aspects of the present invention, comparing the cases where the driving points are spaced apart from the fulcrum in one of the front direction and the rear direction, the entire device can be made compact in the case the driving points are placed on the front side of the seat of the user.  
         [0044]     In some aspects of the present invention, it is preferable that the swing device further include:  
         [0045]     an operation member coupled to transmit an operation signal according to an operation by the user; and  
         [0046]     a processor configured to specify a movement mode of a virtual moving object in a virtual space in response to the operation signal from the operation member, wherein:  
         [0047]     the first driving mechanism drives the first driving point according to the movement mode of the virtual moving object specified by the processing means (fifth aspect).  
         [0048]     In the fifth aspect of the present invention, the user can recognize the movement mode of the moving object determined by the processor based on the operation that the user performs by himself/herself. Accordingly, it is possible to make the user body sense a rising, lowering or turning feeling, or the like with higher reality by activating the first driving mechanism according to the movement mode of the moving object, e.g., in the case where the moving object rises, the first driving point is driven so as to raise the front portion of the swing member, and in the case where the moving object lowers, the first driving point is driven so as to lower the front portion of the swing member.  
         [0049]     In some aspects of the present invention, it is preferable that the swing device further include:  
         [0050]     a display device placed on a front side of the riding position of the user in the longitudinal direction of the swing member, to display one of a video image of a virtual moving object moving in a virtual space and a video image of a virtual space drawn from a virtual viewpoint moving in the virtual space, wherein:  
         [0051]     the first driving mechanism drives the first driving point according to a movement mode of one of the virtual moving object and the virtual viewpoint (sixth aspect).  
         [0052]     In the sixth aspect of the present invention, the first driving mechanism is operated according to the movement mode of the moving object or the virtual viewpoint recognized by the user based on the video image displayed by the display device. Thus, it is possible to make the user body sense a rising/lowering feeling or a turning feeling or the like with much higher reality.  
         [0053]     In the sixth aspect of the present invention, the video movie can be a video image of a real moving object moving in a real space, a video image of a landscape, an animation video image or a video image created using computer graphics. In a case with the former video images, the first driving mechanism can be operated according to the movement mode of the real or virtual moving object or the real or virtual viewpoint (video camera) recorded in the recording means in advance. In a case with the latter video image, the movement mode of the virtual moving object or the virtual viewpoint can be determined based on data used for creating the computer graphics, and the first driving mechanism can be operated according to the determined movement mode.  
         [0054]     The display device of the sixth aspect of the present invention may be mounted at a position in front of the riding position of the user on the swing member as shown in  FIGS. 1A, 1B  and  2 A to  2 C, or at a position in front of the swing member spaced apart therefrom. In the case where the display device is mounted on the swing member, a liquid crystal monitor, which is lighter in weight and has a higher resistance against vibration than other display devices such as a CRT, is preferably used.  
         [0055]     In some aspects of the present invention, each of the first and second driving mechanism is preferably placed orthogonal to a line connecting the fulcrum and the first and second driving points, respectively, while the swing member is placed at a reference position (seventh aspect).  
         [0056]     That is, assuming spheres whose radii correspond to a line segments connecting the fulcrum and the first and second driving points, it is mechanically desirable that each of the first and second driving mechanisms be positioned in a tangential direction with respect to each of the spheres. However, in a case of actually positioning the first and second driving mechanism as described above, support stages of the first and second driving mechanisms are spaced apart from each other, with an disadvantageous result that a width of the entire game machine becomes larger. Thus, as described above, it is preferable that the first and second driving mechanisms are positioned such that each the operational direction of the driving mechanisms is orthogonal to the line connecting the fulcrum P 0  and the driving points P 1  in a reference state of the swing member (e.g., a state where the swing member is placed at a standard position). As a result, the driving efficiency of the driving mechanisms can be enhanced in the expanding and contracting directions, and at the same time the width of the entire device can be designed compact.  
         [0057]     In some aspects the present invention relates to a control method for a swing device,  
         [0058]     the swing device comprising: 
        a swing member on which a user rides;     an operation member coupled to transmit an operation signal in response to an operation by the user;     a processor configured to specify a movement mode of a virtual moving object in a virtual space in response to the operation signal from the operation member;     a fulcrum support mechanism that supports the swing member at the fulcrum, the fulcrum being placed on a rear side of a riding position of the user of the swing member in the longitudinal direction of the swing member; and     a first driving mechanism that swingably supports the swing member at a first driving point thereof and driving the first driving point in a vertical direction, the first driving point being spaced apart from the fulcrum in a longitudinal direction of the swing member,        
 
         [0064]     the control method comprising: 
        operating the first driving mechanism so that a front portion of the swing member rises, in a case where the movement mode of the virtual moving object specified by the processor indicates rising in the virtual space; and     operating the first driving mechanism so that the front portion of the swing member lowers, in a case where the movement mode of the virtual moving object specified by the processor indicates lowering in the virtual space (eighth aspect).        
 
         [0067]     In the eighth aspect of the present invention, the user can recognize the movement mode of the moving object determined by the processor based on the operation that the user performs by himself/herself. Accordingly, the effect similar to that of the fifth aspect of the present invention can be attained.  
         [0068]     In some aspects, the present invention relates to a control method for a swing device,  
         [0069]     the swing device comprising: 
        a swing member on which a user rides;     a display device placed on a front side of a riding position of the user in the longitudinal direction of the swing member, to display one of a video image of a virtual moving object moving in a virtual space and a video image drawn from a virtual viewpoint moving in the virtual space;     a fulcrum support mechanism that supports the swing member at a fulcrum, the fulcrum being placed on a rear side of the riding position of the user of the swing member in the longitudinal direction of the swing member; and     a first driving mechanism that swingably supports the swing member at a first driving point thereof and moves the first driving point in a vertical direction, the first driving point being spaced apart from the fulcrum in a longitudinal direction of the swing member,        
 
         [0074]     the control method comprising: 
        operating the first driving mechanism so that a front portion of the swing member rises, in a case where one of the virtual moving object and the virtual viewpoint rises in the virtual space; and     operating the first driving mechanism so that the front portion of the swing member lowers, in a case where one of the virtual moving object and the virtual viewpoint lowers in the virtual space (ninth aspect).        
 
         [0077]     In the ninth aspect of the present invention, the user can recognize the movement mode of the moving object or the virtual viewpoint based on the video image displayed on the display device. Accordingly, the effect similar to that of the sixth aspect of the present invention can be attained.  
         [0078]     Note that, the eighth and ninth aspects of the present invention may include additional structures like in the second to seventh aspects of the present invention, in which a swing member further includes a second driving mechanism for driving a second driving point spaced apart from a fulcrum in the longitudinal direction and spaced apart from the first driving point in the lateral direction is used, or the first and second driving mechanisms are operated so that a front portion of the swing member rises or lowers according to the rising or the lowering of the virtual moving object or the virtual viewpoint. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0079]     In the accompanying drawings:  
         [0080]      FIG. 1A  is an explanatory view illustrating a structure of an exemplified swing game machine;  
         [0081]      FIG. 1B  is an explanatory view illustrating the structure of the exemplified swing game machine;  
         [0082]      FIG. 2A  is an explanatory view illustrating a driving manner of a swing member of a swing game machine of a conventional structure;  
         [0083]      FIG. 2B  is an explanatory view illustrating a driving manner of a swing member of a swing game machine of a structure of an embodiment of the present invention;  
         [0084]      FIG. 2C  is an explanatory view illustrating a driving manner of the swing member of a swing game machine of the structure of an embodiment of the present invention;  
         [0085]      FIG. 3  is a perspective view illustrating an outer structure of a swing game machine according to an embodiment of the present invention;  
         [0086]      FIG. 4A  is a perspective view illustrating a structure of the swing game machine according to the embodiment of the present invention;  
         [0087]      FIG. 4B  is a side view illustrating the structure of the swing game machine according to the embodiment of the present invention;  
         [0088]      FIG. 4C  is a front view illustrating the structure of the swing game machine according to the embodiment of the present invention;  
         [0089]      FIG. 4D  is a rear view illustrating the structure of the swing game machine according to the embodiment of the present invention;  
         [0090]      FIG. 5A  is an explanatory view illustrating a structure of a fulcrum support mechanism;  
         [0091]      FIG. 5B  is an explanatory view illustrating a structure of a universal joint;  
         [0092]      FIG. 5C  is an explanatory view illustrating a structure of an electric linear actuator;  
         [0093]      FIG. 6  is a block diagram illustrating a control unit of the swing game machine according to an embodiment of the present invention;  
         [0094]      FIG. 7  is a flowchart illustrating a method of processing executed in the swing game machine according to the embodiment of the present invention;  
         [0095]      FIG. 8A  is an explanatory view illustrating a tilt mode of a swing member in a case where a moving object is raised;  
         [0096]      FIG. 8B  is an explanatory view illustrating a tilt mode of the swing member in a case where the moving object is lowered;  
         [0097]      FIG. 8C  is an explanatory view illustrating a tilt mode of the swing member in a case where the moving object is turned right; and  
         [0098]      FIG. 8D  is an explanatory view illustrating a tilt mode of the swing member in a case where the moving object is turned left. 
     
    
     DETAILED DESCRIPTION  
       [0099]     Hereinafter, embodiments of the present invention will be explained referring to a body-sensible swing game machine  1  as an example in which a movement mode of a virtual moving object M (e.g., fighter aircraft) in a virtual space is determined based on an operation with respect to an operation member and the determined movement mode is displayed on a display device.  
         [0100]      FIG. 3  is a perspective view illustrating an outer structure of the swing game machine  1  to which a swing device according to various embodiments of the present invention is applied, and  FIGS. 4A  to  4 D are perspective, side, front, and rear views, respectively, illustrating the swing game machine  1  from which a casing frame is removed.  
         [0101]     As shown in the figures, the swing game machine  1  mainly includes a base stage  10 , a swing member  20 , a fulcrum support mechanism  30 , a driving mechanism storing unit  40 , and a money processing machine  60 .  
         [0102]     Of those, the base stage  10  serves as a seating to which the fulcrum support mechanism  30 , a first driving mechanism  41   a , a second driving mechanism  41   b , a static determinate maintaining mechanism  50 , and so on to be described later are provided. In an inner space of the base stage  10 , a control unit  80  for controlling an operation of the game machine  1 , various connection cables, and the like can be stored.  
         [0103]     Note that the base stage  10  is unnecessary in a case where the fulcrum support mechanism  30 , the first driving mechanism  41   a , the second driving mechanism  41   b , the static determinate maintaining mechanism  50 , and the like are directly installed on a floor surface of a facility in which the game machine  1  is installed.  
         [0104]     The swing member  20  includes a floor member  21  extending in a longitudinal direction, a mounting stage  22  provided to a front portion of the floor member  21 , a reinforcing frame  23 , and so on. On the floor member  21 , a seat  24  (e.g., having a shape similar to a cockpit of a fighter aircraft) is provided. To the mounting stage  22 , an operation panel  25  to receive input from a user indicative of various game operations is provided and a display device  26  supported by the reinforcing frame  23  is provided.  
         [0105]     The operation panel  25  includes a steering rod  25   a  being an operation member with which the user instructs a movement direction and the like of the moving object M. By operating the steering rod  25   a  in forward and backward directions, the moving object M can be raised and lowered, and by operating the steering rod  25   a  in left and right directions, the moving object M can be turned left and right. The operation panel  25  further includes operation members  25   b  and  25   c  with which a game is started, items of the game are selected, and other operations are performed. Further, an auxiliary operation member  25   d  is arranged at a side of the seat  24 .  
         [0106]     The display device  26  displays a video image showing a movement mode of the moving object M in the virtual space, which is operated by the user. The video image can be an arbitrary video image with which the user can recognize the movement mode of the moving object M. Examples thereof includes a video image of the moving object M observed from a viewpoint fixed in the virtual space, and a video image of the moving object M observed from a viewpoint inside or behind the moving object M, which is movable in the virtual space together with the moving object M while maintaining a predetermined positional relation therewith.  
         [0107]     As the display device  26 , a liquid crystal monitor, which is highly resistant to vibration compared to other display devices such as a CRT, is preferably used. As the liquid crystal monitor is light in weight, the display device  26  having a large screen size as shown in the figures can be used. Therefore, a game image with a visual impact can be displayed.  
         [0108]     The swing member  20  is supported by a mechanism to be described later in such a manner that the swing member  20  is spaced apart from the base stage  10  by a predetermined distance so as to enable the swing member  20  to perform movements including rolling and pitching.  
         [0109]     The fulcrum support mechanism  30  is arranged at a position spaced apart from the seat  24  being a riding position of the user of the swing member  20  by a predetermined distance therebehind.  
         [0110]      FIG. 5A  is an enlarged sectional view illustrating the fulcrum support mechanism  30 .  
         [0111]     As shown in the figure, the fulcrum support mechanism  30  includes: a support column  31  having a square pole shape and projecting upright on the base stage  10 ; a boll joint  32  fixed to an upper end of the support column  31 ; a fixation block  33  provided to the floor member  21  so as to cover an opening  21   a  defined in the floor member  21 , and having a square-C-shaped space for storing the ball joint  32  therein; and a cover  34  for covering an upper portion of the fixation block  33 .  
         [0112]     The ball joint  32  includes: a shaft bearing member  32   a  having a sphere-shaped space defined therein; a ball portion  32   b  rotatably received and held in the sphere-shaped space; and a ball shaft  32   c  having an end to which the ball portion  32   b  is attached. The other end of the ball shaft  32   c  is inserted and fixed to an insertion hole  33   a  defined in a ceiling of the fixation block  33  with a nut or the like.  
         [0113]     Accordingly, the swing member  20  is swingably supported on the support column  31  so that the ball portion  32   b  of the ball joint  32  serves as an unmovable fulcrum.  
         [0114]     In the driving mechanism storing unit  40  located in a front portion of the game machine  1 , the first driving mechanism  41   a , the second driving mechanism  41   b , and the static determinate maintaining mechanism  50  are stored.  
         [0115]     The first and second driving mechanism  41   b ,  41   b  include: support stages  42   a  and  42   b  provided on left and right portions of an upper front portion of the base stage  10 ; universal joints  43   a  and  43   b  provided at the upper ends of the support stages  42   a  and  42   b ; electric linear actuators  44   a  and  44   b  provided to the universal joints  43   a  and  43   b ; and universal joints  45   a  and  45   b  provided to the tip ends of operation rods of the electric linear actuators  44   a  and  44   b , respectively. The universal joints  45   a  and  45   b  support the swing member  20  at pads  23   a  and  23   b  fixed to mounting bases of the reinforcing frame  23 , which is mounted to the mounting stage  22 .  
         [0116]     Note that the distance from the pad  23   a  to the ball portion  32   b  of the ball joint  32  being the fulcrum of the swing member  20  is the same as the distance from the pad  23   b  to the ball portion  32   b . Further, the support stages  42   a  and  42   b  are provided so that the axial directions of the electric linear actuators  44   a  and  44   b  in a stand-by state are substantially orthogonal to the lines connecting the ball portion  32   b  being the fulcrum of the swing member  20  and the pads  23   a  and  23   b , respectively.  
         [0117]     Herein, the universal joints  43   a ,  43   b ,  45   a , and  45   b  are similarly structured, and an enlarged explanatory view illustrating the structure thereof is shown in  FIG. 5B .  
         [0118]     As shown in the figure, each of the universal joints  43   a ,  43   b ,  45   a , and  45   b  includes: a cross shaft  43   x  having two shaft members  43   x   1  and  43   x   2  orthogonally crossed and fixed to each other; a lower plate  43   y  having on an upper surface thereof a pair of shaft bearing portions  43   y   1  for rotatably supporting both ends of one shaft member  43   x   1 ; and an upper plate  43   z  having on a lower surface thereof a pair of shaft bearing portions  43   z   1  for rotatably supporting both ends of the other shaft member  43   x   2 . Thus, a member provided to an upper surface of the upper plate  43   z  is swingably supported with respect to a member provided to a lower surface of the lower plate  43   y.    
         [0119]      FIG. 5C  is an explanatory view illustrating a structure of the electric linear actuators  44   a  and  44   b.    
         [0120]     As shown in the figure, each of the electric linear actuators  44   a  and  44   b  mainly includes in a cylinder-shaped casing  44   1 ; a servo motor  44   2 ; a boll screw shaft  44   3  rotationally driven by the servo motor  44   2 ; a ball circulation nut  44   4  screwed by the boll screw shaft  44   3  and prohibited to rotate together with the boll screw shaft  44   3 ; and an operation rod  44   5  integrally fixed to the ball circulation nut  44   4 . The ball circulation nut  44   4  converts a rotational movement of the boll screw shaft  44   3  by the servo motor  44   2  into a liner movement, thereby driving the operation rod  44   5  forward and backward in the shaft direction thereof.  
         [0121]     Accordingly, the swing member  20  is swingably supported by the universal joints  45   a  and  45   b  via the pads  23   a  and  23   b  being driving points, and is driven so as to be vertically moved by the forward and backward movement of the operation rod  44   5  of the electric linear actuators  44   a  and  44   b.    
         [0122]     As illustrated, the static determinate maintaining mechanism  50  includes: a support shaft  51  projectingly provided to the reinforcing frame  23  at a midst position between the pads  23   a  and  23   b  being the driving points of the swing member  20 ; a support stage  52  provided on a front portion of an upper surface of the base stage  10  and a guide frame  53  provided on the upper surface of the support stage  52  with a predetermined slant angle and having a guide hole  53   a , in which the support shaft  51  is rotatably inserted, for guiding the support shaft  51  only in the vertical direction.  
         [0123]     Herein, the support shaft  51  is provided in such a manner that an axial center thereof directs the ball portion  32   b  being the fulcrum of the swing member  20 . The support shaft  51  is guided by the guide hole  53   a , whereby the degree of freedom of the movement of the swing member  20  is limited to the vertical movement along the guide hole  53   a  of the support shaft  51  (pitching), and the rotational movement of the swing member  20  about the support shaft  51  (rolling). Thus, static determinate of the swing member  20  is prevented from being lost while the swing member  20  is driven by the electric linear actuators  44   a  and  44   b.    
         [0124]     The money processing machine  60  may include: a coin insertion opening  61  defined in an outer surface of the casing, for receiving a game fee; and a coin processing unit  62  provided inside the casing, for detecting an inserted coin and transmitting a coin detection signal to the control unit  80 .  
         [0125]      FIG. 6  is a block diagram illustrating a configuration of the control unit  80  of the swing game machine  1 .  
         [0126]     As shown in the figure, the control unit  80  includes a main game board  81 , an interface I/O board (JVS I/O BD)  82 , a solid state relay (SSR) control board (relay BD)  83 , a swing control board (MOTION PC)  84 , a left drive control circuit  85 , a right drive control circuit  86 , an image processing circuit  87 , and an audio sound processing circuit  88 .  
         [0127]     Herein, the main game board  81  includes a CPU, ROM, RAM, and the like and integrally controls the operation of the game machine  1 . To be specific, the CPU expands a game program and a system program stored in the ROM in advance on the RAM, performs computing according to an operation signal input from the various operation members  25   a  to  25   d  via the interface I/O board  82  to compute movement mode and the position of the moving object M in the virtual space momentarily, and transmits a tilt angle instruction signal for instructing a pitching angle and a rolling angle of the swing member  20  to the swing control board  84  based on a result of the computation. Further, the main game board  81  generates a drawing command and an audio sound command as tasks for drawing a performance image and outputting a performance audio sound, and transmits the commands to the image processing circuit  87  and the audio sound processing circuit  88 , respectively.  
         [0128]     The solid state relay control board  83  generates a safety signal for instructing to suspend the movement of the electric linear actuators  44   a  and  44   b  in response to a signal from a detection sensor  28  provided in the vicinity of the game machine  1 , and transmits the signal to the swing control board  84 . Examples of the detection sensor  28  includes a mechanical sensor for detecting a seatbelt wearing state at the seat  24  and an optical sensor for detecting that a person is approaching a dangerous portion of the game machine  1 .  
         [0129]     The swing control board  84  includes a CPU, ROM, RAM, and the like for processing the driving of the swing member  20 , and controls the driving of the electric linear actuators  44   a  and  44   b  according to a swing control program expanded from the ROM onto the RAM and in response to the signals from the main game board  81  and the solid state relay control board  83 .  
         [0130]     To be specific, the swing control board  84  determines a rotational direction and a rotational rate of the servo motor  44   2  in the electric linear actuators  44   a  and  44   b  in response to the tilt angle instruction signal from the main game board  81 , and transmits a driving signal for instructing the rotational direction and the rotational rate to the left and right drive control circuits  85  and  86 . Further, in a case of receiving the safety signal indicating that a seatbelt is not worn, a person is approaching a dangerous portion, or the like, the transmittance of the driving signal to the left and right drive control circuits  85  and  86  is suspended.  
         [0131]     The left and right drive control circuits  85  and  86  control the rotation of the servo motors  44   2  in the electric linear actuators  44   a  and  44   b  in response to the driving signal from the interface I/O board  82 , thereby controlling the pitching and the rolling of the swing member  20 .  
         [0132]     The image processing circuit  87  performs a drawing processing of the game image in response to the drawing command from the main game board  81 , which is displayed on the display device  26 . The audio sound processing circuit  88  causes, for example, left and right speakers  27   a  and  27   b  embedded in a backrest of the seat  24  to output a game audio sound synthesized based on the audio sound command from the main game board  81 .  
         [0133]      FIG. 7  is a flowchart illustrating an outline of processing executed in the main game board  81 .  
         [0134]     As shown in the figure, when the money processing machine  60  receives the detection signal indicating insertion of a predetermined game fee (S 11 ), the main game board  81  starts game processing (S 13  to S 17 ), on receiving a game start operation with respect to the operation member  25   b  or  25   c  or the like (S 12 ).  
         [0135]     In the game processing, the following processing is executed in every frame-times.  
         [0136]     That is, the main game board  81  checks presence/absence of an operation signal from the steering rod  25   a  (S 13 ), and according to the presence/absence and the content of the signal, determines the movement mode and the position of the moving object M in the virtual space (S 14 ).  
         [0137]     Next, the main game board  81  places the moving object M at the position determined at S 14  in the virtual space in which various objects are arranged to construct a virtual model, and generates a game image as if the image is drawn from a virtual viewpoint located at the predetermined position (e.g., behind the moving object M) (S 15 ). Further, the main game board  81  generates the tilt angle instruction signal based on the attitude, the movement mode and the like of the moving object M obtained at S 14 , and transmits the signal to the swing control board  84  (S 16 ).  
         [0138]     Then, at S 17 , whether or not the predetermined gameover condition is established is detected. In a case of being established, the game end processing is executed (S 18 ), and in a case of being unestablished, the processing is returned to  13  in order to execute the game processing in the subsequent frame-time.  
         [0139]      FIGS. 8A  to  8 D are explanatory views illustrating the various swing modes of the swing member  20  while the game is in progress.  
         [0140]      FIG. 8A  illustrates a swing mode in a case where a raising operation is performed with respect to the steering rod  25   a . In this case, the operation rods  44   5  of the electric linear actuators  44   a  and  44   b  extend with an identical feeding amount to thereby drive upward the pads  23   a  and  23   b  being the driving points. As a result, the swing member  20  tilts in a direction in which a user O faces upward, and at the same time, a vertical position of the user O is heightened. Accordingly, due to the change of the posture and the height, the user O can sense a rising feeling extremely impressively. Further, as a video image showing that the moving object M is rising is displayed on the display device  26 , the reality of the rising feeling of the user O can further be enhanced.  
         [0141]      FIG. 8B  illustrates a swing mode in a case where a lowering operation is performed with respect to the steering rod  25   a . In this case, the operation rods  44   5  of the electric linear actuators  44   a  and  44   b  contract with an identical feeding amount to thereby drive downward the pads  23   a  and  23   b  being the driving points. As a result, the swing member  20  tilts in a direction in which a user O faces downward, and at the same time, the vertical position of the user O is lowered. Accordingly, due to the change of the posture and the height, the user O can sense a lowering feeling extremely impressively. Further, as a video image showing that the moving object M is lowering is displayed on the display device  26 , the reality of the lowering feeling of the user O can further be enhanced.  
         [0142]     Each of  FIGS. 8C and 8D  illustrates a swing mode in a case where a right-turning operation or a left-turning operation is performed with respect to the steering rod  25   a . In these cases, each of the operation rods  44   5  of the electric linear actuators  44   a  and  44   b  extends or contracts in such a manner that the heights of the pads  23   a  and  23   b  are made different to each other. As a result, the swing member  20  is tilted right or left to make the user O sense a right-turning feeling or a left-turning feeling. Further, at the same time, as a video image showing that the moving object M is turning right or left is displayed on the display device  26 , the reality of the turning feeling of the user O can further be heightened.  
         [0143]     Note that, in a case where the operation rod  44   5  of one of the electric linear actuators  44   a  and  44   b  is extended by a predetermined amount and the operation rod  44   5  of the other of the electric linear actuators  44   a  and  44   b  is maintained at a neutral position, the swing member  20  tilts right or left (rolling) and at the same time tilts in the direction in which the user O faces upward (pitching). Accordingly, the user O can sense a combined feeling of a turning feeling and a rising feeling. Likewise, in a case where the operation rod  44   5  of one of the electric linear actuators  44   a  and  44   b  is contracted by a predetermined amount and the operation rod  44   5  of the other of the electric linear actuators  44   a  and  44   b  is maintained at the neutral position, the swing member  20  tilts right or left (rolling) and at the same time tilts in the direction in which the user O faces downward (pitching). Accordingly, the user O can sense a combined feeling of a turning feeling and a lowering feeling. As such, the tilt of the swing member  20  can be changed in the various modes.  
         [0144]     The present invention has been explained by way of the exemplified embodiments. However, the present invention is not limited to the above-mentioned embodiments of the present invention, and various modifications and alterations can be made within the scope of the claims.  
         [0145]     For example, in the above-mentioned embodiments of the present invention, description has been made by way of an example in which the left and right driving points  23   a  and  23   b  and the driving mechanisms  41   a  and  41   b  are provided to the front side of the ball portion  32   b . However, the driving points  23   a  and  23   b  and the driving mechanisms  41   a  and  41   b  may be provided to the rear side of the ball portion  32   b . In this case, for example, when a raising operation is performed with respect to the steering rod  25   a , the driving points  23   a  and  23   b  are driven downward, and when a lowering operation is performed with respect to the steering rod  25   a , the driving points  23   a  and  23   b  are driven upward. As such, a swing game machine operating in a similar manner to that of the above-mentioned embodiment of the present invention can be realized except that the driving direction of the driving points are different from that of the above-mentioned embodiments of the present invention.  
         [0146]     Further, in the above-mentioned embodiments of the present invention, by adjusting the distance between the seat  24  being the riding position of the user and the ball portion  32   b , the distances between the ball portion  32   b  and the driving points  23   a  and  23   b , the distance between the driving points  23   a  and  23   b , and the like, the degree of the change of the tilt angle of the swing member  20  by extending or contracting the operation rods  44   5  of the driving mechanisms  41   a  and  41   b  by the same amount, the distance that the user moves in vertical direction by the tilt of the pitching of the swing member  20  by the same angle, and the like can be adjusted.  
         [0147]     Further, in the above-mentioned embodiments of the present invention, description has been made by way of an example in which the electric linear actuators  44   a  and  44   b  are employed in the driving mechanisms. However, any arbitrary means can be used to vertically drive the driving points  23   a  and  23   b . For example, the driving points  23   a  and  23   b  can be driven in a similar manner to that of the above-mentioned embodiment of the present invention by employing another mechanism such as an oil hydraulic cylinder. Alternatively, the driving points  23   a  and  23   b  can be hung from an upper position of the game machine  1  and driven by towing or the like.  
         [0148]     In addition, the shape, the dimension, and the like of the respective members constituting the swing game machine of the above-mentioned embodiments of the present invention are merely described as examples. Any alternative shape and dimension can be employed to implement the present invention.