Abstract:
A mouse interface system is provided that allows a user to feel a virtual object displayed by a computer on a display device. The system includes (a) a force feedback device for providing the user with kinesthetic feedback related to mechanical properties in a predetermined direction of the virtual object, (b) a tactile feedback device for providing the user with normal stimulation related to texture of the virtual object, and (c) a linear actuator for providing the tactile feedback device with a translational movement so that the distal end portion of each pin moves in a substantially lateral direction with respect to the user&#39;s skin.

Description:
PRIORITY CLAIM  
       [0001]     This application claims under 35 U.S.C. § 119 the benefit of the filing date of Oct. 21, 2003 of Korean Application No. 2003-73554, the entire contents of which are incorporated herein by reference.  
       BACKGROUND  
       [0002]     1. Technical Field  
         [0003]     The invention relates to a mouse system for computers, which produces a force feedback, and more particularly, to a tactile mouse interface system for computers, which provides a force feedback to a user&#39;s wrist or arm, or provides tactile and kinesthetic feedback of a virtual object to the user&#39;s fingers.  
         [0004]     2. Related Art  
         [0005]     In general, computer users experience virtual objects in games and simulations based on virtual realities, which are provided by computers. Interface devices used for computer-user interaction include a mouse, a joystick, a steering wheel, a tablet and so on. Such interface devices apply control signals or commands to virtual objects displayed on monitors of computers, or allow users to physically feel the virtual objects. Accordingly, interface devices require force feedback units, which are familiar to users so as to allow users to feel virtual objects.  
         [0006]     U.S. Pat. No. 6,191,774 discloses a conventional mouse interface system that provides force feedback to a user&#39;s hand as shown in  FIG. 1 . A mouse interface system  40  is connected to a host computer and provides force feedback to a user&#39;s hand. A user can feel feedback of a virtual object. Specifically, the mouse interface system  40  includes a mouse  10 , a mechanical linkage  20  and a transducer system  30 . The mechanical linkage  20  is provided on a base member  25 . First, second, third and fourth links  21 ,  22 ,  23  and  24  are connected to each other in the mechanical linkage  20 , and the mouse  10  is connected to one end of the fourth link  24 . In this case, the mechanical linkage  20  is rotatably coupled to one or more bearings, so that force feedback is transmitted to the mouse  10  by the operation of the linkage  20 .  
         [0007]     The transducer system  30  includes a sensor  31  and actuators  32 . The sensors  31  collectively sense a movement of the mouse  10  and transmit electric signals, and the actuator  32  transmits forces to the mouse  10  in two degrees of freedom according to shape of a virtual object.  
         [0008]     With the above-described configuration, the mouse interface system  40  provides force feedback to a user&#39;s hand holding the mouse  10  in such a way that the transducer system  30  operates the linkage  20  according to the shape of a virtual object. The conventional mouse interface system has disadvantages that a user can feel indirect tactile sensation of a virtual object. A user is not allowed to perceive various physical properties of a virtual object, such as size, weight, shape and hardness.  
         [0009]     Another conventional mouse interface systems are disclosed U.S. Pat. Nos. 5,912,660 and 6,278,441. These systems allow a user to feel tactile feedback of a virtual object implemented on a computer. However, the mouse interface systems are limited to provide only force feedback to feel physical properties of a virtual object. The systems are not configured to allow a user to feel kinesthetic feedback (e.g., tactile sensation generated when a virtual object is grazed). The entire contents of each U.S. Pat. Nos. 6,278,441, 6,191,774 and 5,912,660 are incorporated herein by reference.  
       SUMMARY  
       [0010]     An object of the invention is to provide a mouse interface system for providing tactile and kinesthetic feedback, which linearly move pins operated by bimorph actuators, in order to transmit the pressure distribution, vibration and grazing sensation of a virtual object to a user&#39;s fingers while transmitting force feedback to a user&#39; arm. A user can feel the various physical properties of the virtual object, such as weight, size, shape and hardness of a virtual object.  
         [0011]     Another object is to provide a mouse interface system for providing tactile and kinesthetic feedback, which is capable of providing tactile and force sensations to a user&#39;s fingers, such as the thumb and the index finger without disturbing movement of the user&#39;s arm and wrist. This substantially minimizes inconvenience and fatigue that a user may feel.  
         [0012]     In order to accomplish the above object, one embodiment of a mouse interface system for computers is provided. The mouse interface system for computers provides force feedback to the user&#39;s palm and arm by operating a mouse, and provides force feedback or stimulus to the user&#39;s fingers by operating pins placed in a mouse. A user indirectly feels a virtual object on the monitor of a computer. A tactile feedback stimulating unit installed in the mouse transmits stimuli or pressure to a user&#39;s fingers by operating one or more individual actuators according to signals related to a virtual object and controlling the individual pins attached to the actuators. The mouse transmits active kinesthetic feedback to a user&#39;s fingers by receiving a signal related to kinesthetic feedback, which occurs when the virtual object is grazed, from an encoder and linearly moving a slide operated in conjunction with the tactile feedback stimulating unit. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.  
         [0014]      FIG. 1  is a schematic diagram of a conventional mouse interface system that provides force feedback to a user&#39;s hand;  
         [0015]      FIG. 2  is a schematic diagram showing one embodiment of a mouse interface system;  
         [0016]      FIG. 3  is a perspective view of the mouse interface system shown in  FIG. 2 ;  
         [0017]      FIG. 4  is a perspective view of the mouse interface system of  FIG. 3  with a mouse plate removed;  
         [0018]      FIG. 5  is a perspective view showing an internal structure of the mouse that transmits tactile and kinesthetic feedback in the mouse interface system shown in  FIG. 4 ;  
         [0019]      FIG. 6  is a perspective view and  FIG. 7  is a plan view, which show a tactile feedback stimulating unit used in a mouse shown in  FIG. 5 ;  
         [0020]      FIG. 8   a  is a perspective view showing one of bimorph actuators that stimulate user&#39;s fingers in the tactile feedback stimulating unit shown in  FIG. 6 ;  
         [0021]      FIG. 8   b  is an enlarged perspective view showing pins shown in  FIG. 8   a;    
         [0022]      FIG. 9  is a perspective view showing a mechanism of linearly operating the tactile feedback stimulating unit  110  in the mouse  100  shown in  FIG. 5 ;  
         [0023]      FIG. 10  is a perspective view of a force feedback unit used in the mouse interface system shown in  FIG. 3 ; and  
         [0024]      FIG. 11  is a partial perspective view of the force feedback unit showing a connection of the motor shaft that operates a linkage shown in  FIG. 10 .  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]     FIGS.  2  to  4  show one embodiment of a mouse interface system.  FIG. 2  show s a mouse interface system that provides tactile and kinesthetic feedback to users. Users can feel a virtual object disposed on a monitor of a computer as shown in  FIG. 2 . Referring to  FIG. 3 , the mouse interface system includes a mouse  100  and a force feedback unit  200 . The mouse  100  includes a plurality of pins  112 , multiple actuators  113 , and a tactile feedback stimulating unit  110 . The force feedback unit  200  includes a second motor  220 , a third motor  221  and a linkage  260 . The linkage  260  is disposed below a mouse plate  231 . The linkage  260  connects the mouse  10  to the force feedback unit  200  as shown in  FIG. 4 .  
         [0026]     The mouse interface system stimulates fingers through the plurality of pins  112  by operating the actuators  113  of the tactile feedback stimulating unit  110 . A user can feel a virtual object implemented on the monitor of a computer. Furthermore, the mouse interface system can transmit active kinesthetic feedback to the user&#39;s fingers by linearly moving the tactile feedback stimulating unit  110  in the mouse  100 . The mouse interface system also allows a user gripping the mouse  100  to feel shape and hardness of a virtual object by operating the linkage  260  through the operation of second and third motors  220  and  221 . Feedback is transmitted to the mouse  100 , which is connected to the linkage  260 .  
         [0027]      FIG. 5  shows an internal structure of the mouse  100  shown in  25   FIG. 4 .  FIGS. 6 and 7  show the tactile feedback stimulating unit  110  that applies stimuli to the user&#39;s fingers in the mouse shown in  FIG. 5 .  FIG. 8   a  shows one of bimorph actuators that stimulate the user&#39;s fingers in the tactile feedback stimulating unit shown  110  in  FIG. 6 .  
         [0028]     As shown in FIGS.  2  to  8 , the tactile feedback stimulating unit  110  is disposed in the mouse  100  and transmits tactile feedback of a virtual object to user&#39;s fingers. The actuators  113  of the tactile feedback stimulating unit  110  are, for example, bimorph bending type piezoelectric actuators  113 . The plurality of pins  112  are perpendicular and attached to the actuators  113 . The actuators  113  control and operate the pins  112  at a predetermined frequency, amplitude and force in accordance with a current applied thereto. The tactile feedback stimulating unit  110  includes three electric wires that are connected to each of the actuators  113 . Signals according to shape of a virtual object are selectively transmitted to the plurality of actuators  113 . With this construction, the plurality of pins  112  stimulate user&#39;s fingers through the operation of the actuators  113  in accordance with shape of a virtual object. In this embodiment, the actuators  113  can be controlled at a frequency of about 1 kHz, which is the upper limit of vibration that can be sensed by a human body, and at a resolution of several micrometers of a front end amplitude. Accordingly, the tactile feedback stimulating unit  110  may form a different pressure distribution by differentiating each height of and force applied to pins  112  attached to the actuators  113 . Furthermore, the tactile feedback stimulating unit  110  simulates superficial properties of a virtual object by making a frequency and/or an amplitude of the pin  112  differ from those of other pins. A user can feel tactile feedback of a virtual object.  
         [0029]     As shown in  FIGS. 6 and 7 , the actuators  113  are attached to stepped portions of an actuator fastening stand  114 . The actuator fastening stand  114  is attached to a first fastening plate  115  to support the actuators  113 . The plurality of pins  112  are attached to one end of each of the actuators  113 . In this embodiment, as shown in  FIG. 8B , the plurality of pins  112  is attached to a block  112   a  having a lateral slot  112   b  and the plurality of pins  112  are combined with each actuator  113  through the block  112   a . Specifically, the lateral slot  112   b  of the block  112   a  is tightly fitted around the actuator  113 . When the actuator  113  and the pins  112   a  are combined with each other in that way, the pins  112  can be easily displaced when necessary. However, it is possible to directly attach the pins  112  to each actuator  113 .  
         [0030]      FIG. 9  illustrates a linear operation of the tactile feedback stimulating unit  110  included in the mouse  100  shown in  FIG. 5 . As shown in  FIGS. 4, 5  and  9 , the tactile feedback stimulating unit  110  is linearly moved in the mouse  100  so that the user can feel kinesthetic feedback. A signal indicating a location where a virtual object is grazed is transmitted to a first encoder  141  of the mouse  100 . Subsequently, a first motor  142  connected to the first encoder  141  is operated to allow the tactile feedback stimulating unit  110  to be linearly moved. The motor shaft of the first motor  142  is connected to a screw shaft  133  via a driving belt  150  so that the screw shaft  133  is operated in conjunction with the first motor  142  in accordance with the rotation of the first motor  142 . In this case, one side of the motor shaft of the first motor  142  and the screw shaft  133  are supported by a first support surface  122  and the other side of the screw shaft  133  is rotatably supported by a second support surface  123 .  
         [0031]     A slide  134  radially surrounds the screw shaft  133  to move along the length of the screw shaft  133 . A thread is formed along the length of the screw shaft  133 . A thread is formed on the slide  134  to engage with the thread of the screw shaft  133 . The slide  134  is combined with a second fastening plate  131 , which is attached to the first fastening plate  115  of the tactile feedback stimulating unit  110 . The second fastening plate  131  is combined with a linear guide  132  to move parallel to the screw shaft  133 . The linear guide  132  is attached to a bottom of the housing of the mouse  100 .  
         [0032]     With the above construction, the slide  134  linearly moves in the longitudinal direction of the screw shaft  133  while being guided by the linear guide  132  in accordance with the operation of the first motor  142 . The tactile feedback stimulating unit  110  operates in conjunction with the slide  134 , so that the pins  112  apply stimulus to a user&#39;s fingers when they graze a user&#39;s fingers.  
         [0033]     Alternatively or additionally, a motor or solenoid whose operation shaft moves in a rectilinear direction, can be mounted in a mouse interface system, in place of the first encoder  141  and the first motor  142 . The slide  134  is connected to that motor or solenoid, and linearly moves by the operation of the motor shaft or solenoid (not shown).  
         [0034]     The mouse  100  transmits force feedback to a user through the operation of the linkage  260  of the force feedback unit  200  as shown in  FIG. 10 .  FIG. 11  is a partial perspective view of the force feedback unit  200  showing a connection of the motor shaft that operates the linkage  260  shown in  FIG. 10 .  
         [0035]     As shown in  FIGS. 3, 4 ,  10  and  11 , the force feedback unit  200  includes a frame  230  including two plates spaced apart from each other at a predetermined interval. The second and third motors  220  and  221  are mounted on a top plate of the frame  230 , and second and third encoders  210  and  211  are attached to the second and third motors  220  and  221 , respectively. The second and third motors  220  and  221  are connected to the four-member linkage  260  inside the frame  230 . As shown in  FIG. 11 , the linkage  260  is held by a first joint  250  attached to the top of the frame  230 . Two link connecting members  240  and  241  are coupled to the motor shafts of the second and third motors  220  and  221  via cables, respectively. The link connecting members  240  and  241  are rotatably fitted around a first joint  250 . The link connecting members  240  and  241  are securely attached to the two links of the linkage  260 , so that the linkage  260  is operated by the rotation of the second and third motors  220  and  221 . A second joint  270  is placed at the location of the linkage  260  opposite to the first joint  250  and is attached to the bottom  121  of the housing of the mouse  100 .  
         [0036]     Referring to  FIG. 10 , a mouse plate  231  attached to the top of the frame  230  is placed between the mouse  100  and the linkage  260  to reduce user fatigue. A connection opening is formed through the mouse plate  231  to interconnect the second joint  270  and the mouse  100 . The connection opening is configured to be larger than an operational range of the second joint  270 . The operation range of the second join  270  may be polar a planar, coordinate range.  
         [0037]     The operation of the mouse interface system is described below. The mouse interface system applies stimuli to a user&#39;s fingers holding the mouse  100  to allow a user to feel the properties of a virtual object displayed on the monitor of a computer. For this purpose, the tactile feedback stimulating unit  110  of the mouse  100  operates the individual pins  112  attached to the plurality of actuators  113  according to signals related to the virtual object, so that the tactile feedback stimulating unit  110  transmits a pressure stimulus, vibration or a tactile sensation to the user&#39;s fingers.  
         [0038]     The mouse interface system operates the tactile feedback stimulating unit  110  of the mouse  100  to linearly move to allow a user to feel the kinesthetic feedback of a virtual object. Specifically, a signal indicating a location where a virtual object is grazed is transmitted to the second and third encoders  210  and  211 , and the first motor  142  rotates the motor shaft. The slide  134  surrounding the screw shaft linearly moves along the screw shaft  133 , which operates in conjunction with the motor shaft. The slide is simultaneously guided by the linear guide  132 . The tactile feedback stimulating unit  110  connected to the slide  134  linearly moves.  
         [0039]     Furthermore, the mouse interface system allows a signal, which corresponds to a palm holding a virtual object on a monitor, to be transmitted to the force feedback unit  200  through the second and third encoders  210  and  211 . Then, the force feedback unit  200  operates the second and the third motors  220  and  221  according to signals input to the second and third encoders  210  and  211 . The linkage  260  integrated with the mouse  100  operates. The mouse  100  transmits force feedback to the user&#39;s palm and arm through the operation of the linkage  260 , so that the user can feel the tactile force, weight, size and hardness of a virtual object.  
         [0040]     As described above, a mouse interface system provides advantages that by transmitting force feedback to a user&#39;s arm, a user can feel the weight, size and hardness of a virtual object implemented on the monitor of a computer, and by transmitting vibrations and a grazing stimulus to a user&#39;s fingers, a user can feel roughness and superficial properties of the virtual object.  
         [0041]     A mouse interface system may be used in various fields, such as a part assembly of Computer Aided Design (CAD), product purchases in on-line shopping malls, and experience of virtual objects on computer games, so that a user senses and uses the properties of virtual objects on the monitor of a computer.  
         [0042]     It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.