US20070054592A1 - Seat-driving device for simulation system - Google Patents

Abstract

A seat driving device of a simulation system for driving a seat on which a user of the simulation system sits is provided. The seat driving device includes a first member having a spherical surface, a second member making a relative motion with respect to the first member, two wheels rotatably coupled to the second member and rolling on and contacting the spherical surface of the first member, and two driving motors installed on the second member and connected to the wheels to rotate the wheels. The seat is installed on one of the first and second members.

Description

BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• The present invention relates to a seat-driving device of a simulation system, and more particularly, to a seat-driving device of a simulation system which has an improved structure in which a moving or rotation range of a seat depending on a manipulation of a user greatly increases.
• 2. Description of the Related Art
• Simulation systems provide an indirect experience to a user by artificially creating circumstances that can actually occur using computers. Examples of the simulation systems include flight simulation systems, driving simulation systems, etc. It is important for a simulation system to precisely reproduce various circumstances so that a user can feel the sense of the reality and the feeling of movement as much closely to an actual circumstance as possible. To accomplish reproduction of circumstances close to actual circumstances by simulation systems, it is very important to develop software by which a displayed image changes according to a manipulation of a user and hardware, that is, a driving mechanism, for promptly making a motion based on a mathematical model of a moving body, such as, an automobile, an airplane, etc.
• A flight simulation system for use in PCs is an example of a conventional simulation system. In the flight simulation system for use in PCs, no special mechanism for moving or rotating a simulation user is not included, and only a displayed image changes according to software. However, this flight simulation system does not provide a realistic simulation because there are no physical motions of the simulation user. To supplement this disadvantage, that is, to provide a more realistic simulation, the simulation system needs to give physical motions to the user of the simulation system. The physical motions are made by moving, rotating, or vibrating a seat for the user of the simulation system or using other methods.
• Various types of simulation systems in which a simulation user can move physically have been proposed, for example, a simulation system disclosed in U.S. Pat. No. 5,240,417. In this conventional simulation system, a seat for a user or the like is supposed to move or rotate using a motor or a hydraulic device driven according to a manipulation of the user. However, the conventional system has difficulty providing a realistic simulation because a moving or rotating range of the seat is significantly restricted.
• There remains a demand for a seat-driving device to be used in a simulation system capable of providing a more realistic simulation.
SUMMARY OF THE INVENTION
• The present invention provides a seat-driving device of a simulation system which can achieve realistic simulation by greatly increasing a moving or rotation range of a seat depending on a manipulation of a user and is applicable to simulations of various types of vehicles.
• According to an aspect of the present invention, there is provided a seat driving device of a simulation system for driving a seat on which a user of the simulation system sits, the seat driving device including a first member having a spherical surface, a second member making a relative motion with respect to the first member, two wheels rotatably coupled to the second member and rolling on and contacting the spherical surface of the first member, and two driving motors installed on the second member and connected to the wheels to rotate the wheels. The seat is installed on one of the first and second members.
BRIEF DESCRIPTION OF THE DRAWINGS
• The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
• FIG. 1 is a schematic cross-sectional view of a seat-driving device of a simulation system according to an embodiment of the present invention;
• FIGS. 2A through 2H illustrate rotations of a first member shown inFIG. 1; and
• FIG. 3 is a schematic cross-sectional view of a seat-driving device of a simulation system according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
• Referring toFIG. 1, a seat-driving device of asimulation system1 according to an embodiment of the present invention includes afirst member10 and asecond member20.
• Thefirst member10 has a global shape. In this embodiment, thefirst member10 has a perfect global shape. Thefirst member10 may be manufactured of metal. Thefirst member10 is preferably formed of engineering plastic or other lightweight materials to reduce the weight of thefirst member10 and the rotational inertia.
• Aseat40, on which a user of thesimulation system1 can sit, is installed within thefirst member10.
• Thefirst member10 includes amanipulator14, adisplay11, and agyro sensor12.
• As shown inFIG. 1, themanipulator14 has a control lever shape and is combined with theseat40 so that the user of thesimulation system1 can manipulate thesimulation system1 on theseat40 using themanipulator14. Themanipulator14 may be a manipulatable remote controller separated from theseat40. In some cases, themanipulator14 may not be included in thesimulation system1.
• Thedisplay11 is located in front of the user of thesimulation system1 so that the user can always see the-display11. In some cases, a sound reproducing device which can reproduce a sound corresponding to an image reproduced by thedisplay11 may be installed together with thedisplay11.
• Since thefirst member10 has a moment of inertia, it is important to know an exact rotational speed and an exact position of thefirst member10. Hence, thegyro sensor12 is installed within thefirst member10.
• Thefirst member10 is supported by asupport60 so as to be rotatable with respect to abottom surface90 of a building where thesimulation system1 is installed. A center of thesupport60 is void to receive thesecond member20, and an upper innercircumferential surface67 thereof is concave with a curvature corresponding to a curvature of an outer circumferential surface of thefirst member10. A plurality ofballs65, which rolls and contracts the outer circumferential surface of thefirst member10, are installed on the upper innercircumferential surface67 of thesupport60.
• Preferably, anupper support50 is installed on thefirst member10 to prevent thefirst member10 from being detached from thesupport60.
• Thesecond member20 can make a relative motion with respect to thefirst member10. Twowheels30 and31 are coupled to thesecond member20, and twodriving motors35 and36 are installed within thesecond member20.
• The twowheels30 and31 are coupled to thesecond member20 to be rotatable with respect to thesecond member20 and roll on and contact the outer circumferential surface of thefirst member10. The entire surface of each of thewheels30 and31 or at least a portion of each of thewheels30 and31 that contacts thefirst member10 is manufactured of a material having a high friction coefficient with respect to the outer circumferential surface of thefirst member10, such as, compressed rubber.
• Central axes of rotation of thewheels30 and31 are placed within a single plane. This means that thewheels30 and31 are symmetrical to each other with respect to a vertical line passing through the center of thefirst member10. The central axes of rotation of thewheels30 and31 are parallel to tangents at points where thewheels30 and31 touch a spherical surface of thefirst member10. In other words, a straight line that connects between the center of thefirst member10 and each of the points where thewheels30 and31 touch the spherical surface of thefirst member10 is perpendicular to the central axes of rotations of thewheels30 and31.
• The twodriving motors35 and36 are connected to thewheels30 and31 and rotate them.
• In this embodiment, thesecond member20 exists under thefirst member10 and is installed within thesupport60. thesecond member20 is installed on a disk-shapedrotating support21 fixed to thebottom surface90 to be rotatable by ashaft24 andbearings25.
• Thesecond member20 includes a movingelement22 and adriving source23 for moving themoving element22. The movingelement22 is driven by thedriving source23 to move between a first position that presses down on thebottom surface90 to prevent rotation of thesecond member20 and a second position that is separated from thebottom surface90 to allow rotation of thesecond member20.
• A solenoid may be properly used as thedriving source23. Other motors may also be used as thedriving source23.
• An operation and advantages of the seat-driving device will now be described in greater detail. When the user issues a command requiring rotation using themanipulator14, the drivingmotors35 and36 are driven, and accordingly, thewheels30 and31 are rotated. When thewheels30 and31 rotate, rotational forces of thewheels30 and31 are transmitted to thefirst member10 due to a frictional force between each of thewheels30 and31 and the outer circumferential surface of thefirst member10 on which thewheels30 and31 roll and contact. Hence, thefirst member10 is rotated, and thus theseat40 installed in thefirst member10 is rotated. rotational speeds and directions of thewheels30 and31 and a rotational speed and a direction of thefirst member10 are controlled by a manipulation of themanipulator14 or according to a pre-input program.
• During simulation, images and the like are updated in real time and displayed on thedisplay11, so that a user can undergo a realistic simulation.
• A principle in which thefirst member10 is rotated by a rotation of thewheels30 and31 will now be described in detail with reference toFIGS. 2A through 2H.FIGS. 2A through 2H are bottom views of thesimulation system1. Since theseat40 installed in thefirst member10 is rotated by a rotation of thefirst member10, only thewheels30 and31 and thefirst member10 are illustrated inFIGS. 2A through 2H.
• First, coordinate axes and rotational directions are defined for convenience of explanation. As shown inFIG. 1, an axis corresponding to a forward and backward direction of the user sitting on theseat40 is defined by an x-axis, an axis corresponding to a left and right direction of the user sitting on theseat40 is defined by a y-axis, and an axis corresponding to an upward and downward direction of the user sitting on theseat40 is defined by a z-axis. A rotation in one direction at the center point of thefirst member10 about the +x axis is defined by a rotation in a+r_xdirection, and a rotation in the other direction at the center point of thefirst member10 about the +x axis is defined by a rotation in a −r_xdirection. This rotation definition rule is equally applied to the y-axis and the z-axis.
• When thewheels30 and31 rotate at the same speed and in the same direction as shown inFIGS. 2A and 2B, thefirst member10 rotates about the x-axis. Depending on a rotational direction of thewheels30 and31, thefirst member10 may rotate either in the +r_xdirection as shown inFIG. 2A or the −r_xdirection as shown inFIG. 2B.
• When thewheels30 and31 rotate at the same speed and in different directions as shown inFIGS. 2C and 2D, thefirst member10 rotates about the z-axis. Depending on a rotational direction of thewheels30 and31, thefirst member10 may rotate either in a +r_zdirection as shown inFIG. 2C or the −r_zdirection as shown inFIG. 2D.
• When thefirst member10 is desired to rotate about the y-axis, the movingelement22 is moved to the second position separated from thebottom surface90 by the drivingsource23 included in thesecond member20 so that rotation of thesecond member20 is allowed. When the twowheels30 and31 are rotated in directions as shown inFIG. 2E, a difference between the moments of inertia of the first andsecond members10 and20 due to a difference between weights thereof causes thesecond member20 instead of thefirst member10 to rotate about theshaft24 and the rotation axis of thefirst member10 to change as shown inFIG. 2F or2G. When the axis about which thefirst member10 rotates is changed as shown inFIG. 2F or2G, the drivingsource23 included in thesecond member20 is re-driven to move the movingelement22 at the second position to the first position, so that the movingmember22 presses down on thebottom surface90. Thus, the rotation of thesecond member20 is prevented.
• In a state where the rotation of thesecond member20 is hindered as described above, when thewheels30 and31 rotate at the same speed and in the same direction as shown inFIGS. 2F and 2G, thefirst member10 rotates about the y-axis. Even in this case, as in the rotation in the +r_xor −r_xdirection, thefirst member10 may rotate either in the +r_ydirection as shown inFIG. 2G or the −r_ydirection as shown inFIG. 2F depending on a rotational direction of thewheels30 and31.
• Although cases where the twowheels30 and31 rotate in the same direction have been illustrated inFIGS. 2A through 2G, the twowheels30 and31 may be rotated at different speeds to accomplish a complex rotation (i.e., a rotation about an arbitrary axis). For example, when thewheel30 is at a standstill or rotates slowly and thewheel31 rotates in the same direction as that of thewheel30 but at a speed greatly higher than thewheel30 as shown inFIG. 2H, thefirst member10 rotates along a complicate trajectory with a continuous change of the rotational axis of thefirst member10. If the difference between the rotational speeds of the twowheels30 and31 is appropriately adjusted, thefirst member10 may be rotated about a rotational axis slanting in an arbitrary direction. When the twowheels30 and31 rotate in different directions and at different speeds, thefirst member10 may have a more complicate rotation trajectory than when the twowheels30 and31 rotate in the same direction but at different speeds.
• Due to such a rotation of theseat40, a user of thesimulation system1 experiences a rotation about one of the y-axis, the x-axis, and the z-axis or an arbitrary axis on a space defined by the axes in a coordinate established with theseat40 as its center as shown inFIG. 1. Thus, a more realistic simulation is achieved.
• In most applied fields, such as, an automobile or motorcycle driving simulation, an airplane operating simulation, or a roller coaster, a sharp rotation about the y-axis, that is, a rolling in the right and left directions of theseat40, rarely occurs. Generally, the rotation about the y-axis is mixed with rotations about the other axes. Hence, a pure rotation about the y-axis may not be needed during actual simulation, because a desired rotation can be obtained from a complicate rotation (i.e., a rotation about an arbitrary axis) as described below. In the above-described applied fields, the rotatingsupport21, the movingelement22, and the drivingsource23 may not be needed.
• FIG. 3 is a schematic cross-sectional view of a seat-drivingdevice201 of a simulation system according to another embodiment of the present invention. A description of the seat-drivingdevice201 is focused on elements different from those of the seat-driving device ofFIG. 1. The description about the seat-driving device ofFIG. 1 is equally applied to elements-of the seat-drivingdevice201 that are not described. Alternatively, the description about the seat-driving device ofFIG. 1 is properly modified and applied to the not-described elements of the seat-drivingdevice201. Like reference numerals are used to indicate elements that play like technical roles.
• Similar to the seat-driving device ofFIG. 1, the seat-drivingdevice201 ofFIG. 3 includes afirst member210 and asecond member220. Thefirst member210 has a spherical surface and is fixed to abottom surface290 of a building where a simulation system is installed.
• Thesecond member220 is installed to be rotatable with respect to thebottom surface290. Twowheels230 and231 are coupled to thesecond member220 and roll on and contact the spherical surface of thefirst member210. Thesecond member220 includes amotor coupling portion221, aseat coupling portion222, and a clutch225.
• Two drivingmotors235 and236 for rotating thewheels230 and231 are installed on themotor coupling portion221.
• Aseat240 on which a user of the simulation system sits is installed on theseat coupling portion222.
• The clutch225 is installed between themotor coupling portion221 and theseat coupling portion222 and either connects or disconnects themotor coupling portion221 and theseat coupling portion222. An electronic clutch may be used as the clutch225. Other well-known clutches may be used as the clutch225.
• Adisplay211, which a user of the simulation system sees, is installed in front of theseat240. Thedisplay211 is not necessarily installed on theseat240 but can be installed at a position where thedisplay211 can be seen by the user of the simulation system and rotate together with a rotation of theseat240, that is, at a position not causing a relative movement between theseat240 and thedisplay211.
• An operation and advantages of the seat-drivingdevice201 will now be described. Since thefirst member210 is fixed onto thebottom surface290, and thesecond member220 can make a relative movement with respect to thefirst member210, thewheels230 and231 installed on thesecond member220 are rotated on the spherical surface of thefirst member210 by the drivingmotors235 and236. Accordingly, theseat240 is also rotated.
• A mechanism for rotating theseat240 is similar to what is described wit reference toFIGS. 2A through 2H. However, to rotate theseat40 in the r_ydirection, in the embodiment ofFIG. 1, thesecond member20 is rotated without a rotation of thefirst member10 by moving the movingelement22 included in thesecond member20, and the rotational axis of theseat40 is thus changed. On the other hand, to rotate theseat240 in the r_ydirection, in the present embodiment, theseat coupling portion222 and themotor coupling portion221 are mechanically disconnected using the clutch225, and then thewheels230 and231 are rotated at an identical speed and in different directions, so that only themotor coupling portion221 and thewheels230 and231 rotate about the z-axis to thus change the rotational axis of theseat240.
• While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.
• As described above, the present invention can provide a seat driving device for a simulation system which realistically simulates driving of vehicles, such as, airplanes, spacecrafts, automobiles, or motorcycles, riding of roller coasters, etc. In particular, the simulation system can embody a user's feeling of a free rotation in 3 axial directions using only two wheels, so that the structure of the simulation system is very simple.
• The present invention is applicable to games, such as, console box games or mobile games. When a user watches a movie sitting on a seat of the simulation system, he or she can enjoy more realistic images because the seat makes proper rotations depending on images. In other words, the present invention is also applicable to multi-media systems.

Claims (7)

1. A seat driving device of a simulation system for driving a seat on which a user of the simulation system sits, the seat driving device comprising:

a first member having a spherical surface;

a second member making a relative motion with respect to the first member;

two wheels rotatably coupled to the second member and rolling on and contacting the spherical surface of the first member; and

two driving motors installed on the second member and connected to the wheels to rotate the wheels,

wherein the seat is installed on one of the first and second members.

2. The seat driving device ofclaim 1, wherein axes about which the wheels rotate are located within substantially the same plane.

3. The seat driving device ofclaim 1, wherein:

the first member is supported to be rotatable with respect to a bottom surface of a building where the simulation system is installed; and

since the seat is installed on the first member, the first member which rolls on and contacts the wheels is rotated by the wheels rotated by the driving motors, so that the seat is rotated.

4. The seat driving device ofclaim 3, further comprising:

a rotating support supporting the second member to be rotatable with respect to the bottom surface of the building about an axis that is perpendicular to the bottom surface of the building and passes through a center point of the spherical surface of the first member;

a moving element installed on the second member and movable between a first position which presses down on the bottom surface of the building to prevent the second member from rotating and a second position which is separated from the bottom surface of the building to allow the second member to rotate; and

a driving source moving the moving element.

5. The seat driving device ofclaim 3, wherein the axes about which the wheels rotate are parallel to tangent lines at points where the wheels touch the spherical surface.

6. The seat driving device ofclaim 1, wherein:

the second member is supported to be rotatable with respect to a bottom surface of a building where the simulation system is installed; and

since the seat is installed on the second member, and the first member is fixed onto the bottom surface of the building, the wheels which roll on and contact the first member are rotated on the spherical surface of the first member by the driving motors, so that the seat is rotated.

7. The seat driving device ofclaim 6, wherein the second member comprises:

a motor coupling portion on which the driving motors are installed;

a seat coupling portion on which the seat is installed, the seat coupling portion rotatably coupled to the first member; and

a clutch selectively blocking a mechanical connection between the motor coupling portion and the seat coupling portion.

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