Abstract:
A cursor control device horizontally positioned operating surface is mounted on a vertical shaft connected to a biaxial joint which is enclosed in the base of the device. The hand of the operator rests on the operating surface and tips it in any direction so the shaft follows the movement of his/her hand. The motion is interpreted as X and Y coordinates on a computer display screen. The coordinate information is digitized and sent to the main computer to display a cursor on the display screen.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to human interface device and particularly to the coupling of human input to complex electronic and/or mechanical systems such as computer graphical operating systems. 
       BACKGROUND OF THE INVENTION 
       [0002]    Many devices exist for coupling human input to complex electronic and/or mechanical systems such as computers. In a specific embodiment, this invention involves human coupling actions to a computer&#39;s interface graphical operating system using a pointing device. Known devices for addressing a graphical interface include the joystick, mouse, trackball, touch pad, and track point. The latter two are tailored to use in portable (laptop) computers and are typically embedded in the laptop while mice and track balls are external devices that can be used with both laptop or desktop computers. 
         [0003]    While embedded pointing devices offer convenience, their functionality is constrained by their form factor. These devices tend to be small and are generally operated by a single finger. This mode of operation engages only a relatively small group of muscles, thereby limiting precision and accuracy. The touch pad additionally suffers from the need for multiple strokes to achieve long displacements of the cursor; it is difficult to traverse the entire screen with a single motion. Mice and track balls suffer from similar drawbacks concerning long cursor displacements. The travel of the mouse is limited to a constrained region of the user&#39;s work surface and by the user&#39;s reach. Operation often requires the user to lift the device and re-center it on a mouse pad, sometimes repeatedly. The trackball, like the touch pad, almost invariably requires repeated strokes. 
         [0004]    A possible software solution for the multiple-stroke problem could be to have quick movement of the pointing device translated into an exaggerated movement of the cursor. By multiplying the input stroke by its “acceleration”, a long displacement with a single movement can be achieved. However, since the input signal contains some error, the error is magnified along with the increased movement of the cursor resulting in diminished user control. 
         [0005]    A joystick can achieve long displacements without repeated motions. However, its form factor seems to have limited widespread adoption of this device for general purpose pointing. Operating a joystick as a pointing device entails grasping its vertical structure and rocking it off the vertical axis to affect cursor movement. This operation requires awkward bending and twisting of the wrist with the hand in a somewhat unnatural position. Further, switching from the keyboard to the joystick device is a rather slow process as the grip of the joystick must be reestablished. 
         [0006]    Therefore, it is an object of the present invention to provide an improved human/machine interface device. 
         [0007]    It is another object of the present invention to provide a human machine interface device that provides minimal device movement for activation. 
         [0008]    It is a further object of the invention that provides activate positioning with minimal movement of a hand or a portion thereof while the hand is supported in a comfortable palm down position while using the human/machine interface device of the present invention. 
         [0009]    An additional object of the invention is to provide a new human machine interface device that enables easy transference of operation between the device and a keyboard. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0010]    In accordance with the present invention, a substantially horizontally positioned activating surface is mounted for angular motion on a vertical shaft connected to a biaxial joint. The hand of an operator is supported palm down with at least multiple fingers thereof on the activating surface to angularly tip the surface and the shaft in any direction. The angular motion of the shaft is converted to, X and Y, coordinate data by sensors mounted on the biaxial joint. The generated coordinate information is digitized and sent to the main computer to display a cursor on the display screen for the computer. This arrangement provides an improved pointing device, which in operation, engages a larger group of muscles, does not require multiple strokes for achieving long displacements, and is operated with the hand in a natural, palm-down position. It is not necessary that the whole hand be positioned on the activating surface. The device can be operated with the fingers, while the base of the palm rests on a work surface. This position is similar to the position often employed while operating a computer keyboard so that the hand can move smoothly from the keyboard to the cursor activating surface. 
         [0011]    Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with advantages and features, refer to the description and to the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other objects, features and advantages of the invention are more apparent from the following detailed description read in conjunction with the accompanying drawings in which: 
           [0013]      FIG. 1  is a three dimensional depiction of one embodiment of the present invention with the hand operated activation surface shown in phantom; 
           [0014]      FIG. 2  is a schematic presentation of electrical elements of the present invention and their interconnection to a computer. 
           [0015]      FIG. 3  is a plan diagram of a hand contacting plate containing function activation buttons; 
           [0016]      FIG. 4  is a plan view of an interface device incorporating the present invention. 
           [0017]      FIG. 5  is a plan view of an alternative form of the hand contact plate; and 
           [0018]      FIG. 6  is a sectional view along line  5 - 5  of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    Referring to  FIG. 1 , a substantially horizontal activation surface or plate  100  for contact by a human hand  102  is fixed to a vertical shaft  104 . The shaft  104  is mounted on a biaxial joint  106  that allows the activation surface  100  and the shaft  104  to angularly tilt in any direction relative to horizontal and vertical, respectively. A horseshoe shaped element  108  attaches the shaft to one arm  110  of the joint. The horseshoe element is suspended off the base  112  of the hand activated device so that shaft  104  is free to rotate around the arm  110 . A second arm  114  of the biaxial joint  106  is orthogonally oriented with respect to the first arm  110  and is mounted on the base by stanchions  116  and  118  positioned at either end of the arm  114 . Potentiometers  120  and  122  sense the rotation of the arms  110  and  114  relative to the horseshoe shaped collar and the base, respectively. The potentiometers are supplied an activating voltage from a battery (not shown) mounted on the base  112  of the device. 
         [0020]    The potentiometers  120  and  122  have rotational shafts respectively for the purpose of converting angular displacement of the shafts  110  and  112  into electrical signals. Many types of sensors could be used in place of these potentiometers for measuring the angular displacement. Alternatives to the potentiometers include, but are not limited to, optical encoders and magnetic (Hall effect) sensors. The latter two sensor options may reduce mechanical friction and, thereby, reduce wear of the device. 
         [0021]    The plate  100  is maintained in the horizontal position by springs or damping  124  and  126  attached to the base of the hand activated device which springs and damping restrain and center a plate in horizontal or rest configuration so that the potentiometers provide a null output. Alternatively, the forces can be exerted by on the vertical shaft  104 . In place of the springs and dash pot shown in  FIG. 1  alternative forms of restraint can be exerted on the plate  100  or shaft  104 . For example, magnetic, electromagnetic or gravitational (pendulum) devices could exert the restraining forces. 
         [0022]    As shown in  FIG. 2 , the output signals from sensors  120  and  122  are sent over wires  200  along with signals from control buttons, described hereinafter in the discussion of with  FIG. 3 , to a microprocessor  202  containing analog to digital (A/D) converter  204  and a (DMI) output generator  206 . The microprocessor provides signals  208  to a computer  210  controlled by the signals through a cable  212 . 
         [0023]    Computer chip  202  converts the raw angular analog output signals into a digital displacement vector. This vector is used to communicate the user&#39;s intentions relative to movement on a computer screen to the host computer  210  via cable  212  and connector  214 . This communication can be implemented as a proprietary interface by the DMI output generator  206 , or the generator could simply employ one of the many well-known standard interfaces. Suitable interfaces include, but are not limited to, USB, HID, Firewire, or even wireless protocols such as Bluetooth. The angular tipping of the plate causes the cursor to move across the screen. As long as the plate remains tipped from its neutral position, the cursor continues to move. The magnitude of the angular displacement determines the speed of the movement. The cable connection described above is used when the input device is separated from the computer as would be the case of a desk top computer. However if a laptop computer is used the control surface  100  and associated elements would be incorporated into the laptop computer in place of the typical touch pad of such laptops and the cable connector would not be needed. 
         [0024]    Referring to  FIG. 3 , the flat plate  100  of  FIG. 1  may contain button  300  for control functions for the cursor. Examples of functions controlled by these buttons may include menu activation, menu element selection, graphical control actuation scrolling and zooming, as well as other functions normally assigned to the buttons of a mouse. 
         [0025]    When the buttons  300  are located on the plate  100 , the shaft  104  would be hollow so that wires  302  would pass through the hole  304  in the shaft. Alternatively, the control buttons  306  could be located on a flat surface  308  adjacent to the touch plate  100 . In such a case, the connections would not be routed through the hole  304  in the shaft  104 . 
         [0026]    As can be seen with this form of touch plate the heel of hand would lie on the flat surface  308  surrounding the plate such as would be the case of the touch plate incorporated into a laptop computer in place of the typical touch pad. This would mean that the hand would function in the manner similar to hands operating keys of a computer keyboard where the heel of the hand rests comfortably on a flat surface or a pad provided for resting the hand while fingers provide the activating force to angularly tilt the plate. 
         [0027]      FIGS. 4 ,  5  and  6  show an alternative form of the invention. This forum is a standalone mouse substitute. In this standalone device, the touch pad surface  400  is supported in a substantial horizontal orientation on a shaft such as the shaft  104  in  FIG. 1 , extending out of a housing  402 . The housing contains the elements of the mechanism described in  FIG. 1  where the base  112  of  FIG. 1  is the bottom for the housing. This mouse substitute remains stationary in front of a resting surface  404 . The hand (or the fingers thereof) moves the plate  400  on the shaft while the shaft  104  activates the mechanism, described previously. The shaft moves angularly in any direction directed by the touch of the hand. Buttons  406  either on the plate  400  or in the housing  402  are used to provide functions associated with the moving of the cursor on the computer screen. Where the buttons are contained on the surface of the plate, they are wired to the processor  202  shown in  FIG. 2  through the opening or hole  500  in the shaft  104  in the manner shown in  FIG. 3 . As shown in  FIG. 6 , the heel pad  600  of the hand  602  rests on the hand supporting pad  404  while the fingers  604  control the orientation of the touch plate so that the touch plate can be moved by some or all fingers on the hand to change the orientation angle of the shaft in any direction. In no case is it necessary to move the device other than changing the angular over rotation of the touch plate since the angular orientation of the touch plate supplies the motion necessary to have the cursor move across a computer screen. The touch plate is curved to conform to the hand of the operator for comfort and control buttons  606  are positioned on an appendage of the plate bent away from the hand contact area so that they will not be inadvertently contacted by the operator while operating the plate. This not only prevents mistakes but prevents accidental breaking of nails of the operator while operating the touch plate. 
         [0028]    While the preferred embodiment to the invention has been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancement which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.