Ergonomic pointing device

Information

  • Patent Grant
  • 6252582
  • Patent Number
    6,252,582
  • Date Filed
    Tuesday, August 11, 1998
    27 years ago
  • Date Issued
    Tuesday, June 26, 2001
    24 years ago
Abstract
An ergonomic pointing device comprises an orb controller coupled to a resilient return member which is supported on a substrate to move relative to an upper substrate surface of the substrate. The substrate surface has conductive lines and resistive coatings formed thereon or embedded therein. The return member has a conductive surface which is biased with a voltage and is spaced from the substrate surface at rest. When a user applies an external force to the orb controller to move the return member toward the substrate, the conductive surface makes electrical contact with the substrate surface and generates a digital signal. The conductive surface is convex to provide rolling contact with the substrate surface to change the contact location. The orb controller has a curved control surface which is contacted by a digit of a human hand to manipulate movement of the conductive surface relative to the substrate surface. The orb controller has a substantially smaller height than a joystick. The rocking motion created between the conductive surface and substrate surface causes the orb controller to rotate. The rotation of the control surface eliminates the need to rotate the joint of the digit when manipulating the orb controller to move in substantially lateral directions. As a result, the possibility of repetitive stress disorders and pain is greatly reduced.
Description




BACKGROUND OF THE INVENTION




This invention relates generally to pointing devices and, more particularly to an improved pointing device which is ergonomically designed to combine the desirable features of a conventional joystick and a conventional control pad.




Pointing devices including joysticks and control pads are known in the art. Traditional joysticks have been used primarily as a gaming controller, although they have also been employed as general mouse replacement devices. In a typical application, the joystick pointing device is connected via cables to a microcontroller of a computer with a display and a keyboard. The joystick has the advantages of reliability and performance. The joystick also has the advantage of better ergonomic design than the control pad because it allows the digit of the human hand to move laterally without stress to the associated joints of the hand, which means that it is more comfortable to use and less likely to cause any joint damage (e.g., repetitive stress disorder). On the other hand, it has the disadvantage of taking substantial vertical space, which makes it potentially more difficult to physically fit the stick inside a device such as a remote control. Further, the height of the stick makes it more difficult to protect the stick from accidental deflection.




The control pad eliminates the size issues and the associated problems because it takes up no more height than a standard button on a remote control. Unfortunately, they lack the ergonomic advantages of the joystick. More specifically, a conventional disc-type control pad creates significant risk for repetitive stress disorder because, for instance, the pad controller causes the joint of the digit to attempt a rotational movement in the east/west axis (laterally), which causes considerable stress to the joints. Alternately, the user may lift the digit and press the side of the button, but it would result in discontinuous control.




SUMMARY OF THE INVENTION




The present invention provides a pointing device that avoids the problems and disadvantages of the prior art. This goal is accomplished by providing an ergonomic pointing device that functions in an ergonomic manner similar to a joystick but has a significantly reduced height dimension similar to that of a control pad.




In a specific embodiment, a pointing device includes an orb controller which has a much lower physical profile (height) than the joystick. The orb controller has a curved control surface that allows the digits of the hand to move laterally (east/west axis) without causing significant stress on the joints. At rest, the control surface protrudes through an opening in an upper chassis which defines the location for the digit to contact and operate the orb controller. A lower curved contact surface coupled to the orb controller is spaced from a substrate and resiliently supported thereon. When the digit exerts a force on the control surface, the contact surface makes contact with and rolls on the substrate. In another embodiment, the lower contact surface is coupled to the substrate and pivots on the substrate near a center area. Yet another embodiment employs a spring pivoting mechanism coupling the substrate with the orb controller in a manner similar to that described in U.S. Pat. No. 5,675,309, which is incorporated herein by reference in its entirety. The curved control surface allows the digit to move laterally in the east/west direction (as well as north/south, etc.) with ease as the lower contact surface rolls on the substrate. The rotation of the control surface eliminates the need to rotate the joint of the digit, thereby greatly reducing the possibility of repetitive stress disorders and pain.




One aspect of the present invention is a pointing device which comprises a return member being resiliently supported on a substrate surface having an electrically conductive material. The return member has an electrically conductive surface which is substantially convex and spaced from the substrate surface in a first position. A controller is coupled to the return member for moving the return member between the first position and a second position where the electrically conductive surface makes contact with the substrate surface at a contact location. The controller has a disk-like shape with a convex control surface facing away from the substrate surface.




In accordance with another aspect of the invention, a pointing device comprises an electrically conductive surface which is substantially convex. The pointing device further comprises means for supporting the electrically conductive surface relative to a substrate having a substrate surface with an electrically conductive material to move between a neutral position in which the electrically conductive surface is spaced from the substrate surface and a contact position in which the electrically conductive surface makes rolling contact with the substrate surface. A dome-like controller is coupled to the electrically conductive surface and has a convex control surface.




In accordance with another aspect of this invention, a pointing device comprises a control member including an electrically conductive surface facing and spaced in a neutral position from a substrate surface having an electrically conductive material. The control member includes a control surface facing away from the substrate surface. The control member is resiliently supported on the substrate surface to move toward and contact the substrate surface with the electrically conductive surface and to move away therefrom. The electrically conductive surface and the control surface are substantially convex.











BRIEF DESCRIPTION OF THE DRAWINGS




The preferred embodiments of this invention, illustrating all their features, will now be discussed in detail. These embodiments depict the novel and nonobvious pointing device of this invention shown in the accompanying drawings, which are included for illustrative purposes only. These drawings include the following figures, with like numerals indicating like parts:





FIG. 1

is a cross-sectional view illustrating a pointing device in a rest mode in accordance with an embodiment of the present invention;





FIG. 2

is a cross-sectional view illustrating the pointing device of

FIG. 1

in a deflected mode; and





FIG. 3



a


is a top plan view of an orb controller of the pointing device of

FIG. 1

;





FIG. 3



b


is a cross-sectional view along A—A of the orb controller of

FIG. 3



a;







FIG. 3



c


is a cross-sectional view of another embodiment of the orb controller;





FIG. 4



a


is a top plan view of a return member of the pointing device of

FIG. 1

; and





FIG. 4



b


is a cross-sectional view along B—B of the return member of

FIG. 4



a.













DESCRIPTION OF THE PREFERRED EMBODIMENT





FIGS. 1 and 2

show a pointing device


10


having a controller referred to herein as an orb controller


12


because of its shape and movement. The orb controller


12


has a curved control surface


14


which is contacted typically by the digit or digits or a human hand to manipulate movement of the orb controller


12


. In this embodiment, the control surface


14


has a substantially spherical shape to form a dome-like orb controller


12


, but may have other shapes such as an ellipsoidal shape. The control surface


14


protrudes through an opening


16


in an upper chassis


18


which defines the location for the digit to contact and operate the orb controller


12


. The opening


16


is substantially circular to accommodate the substantially spherically shaped control surface


14


. The opening


16


may have other shapes. The opening


16


is sized to expose a sufficient portion of the control surface


14


to allow the digit to operate the full range of movement of the orb controller


12


without lifting the index. The upper chassis


18


is connected to the structure such as a remote control (not shown) which houses the pointing device


10


. The pointing device


10


is in a rest mode in FIG.


1


.

FIG. 2

illustrates the pointing device


10


in a deflected mode when moved by a hand.




The orb controller


12


is connected to a return member


20


which is disposed on a substrate or printed circuit board


22


. In the embodiment shown, the return member


20


is connected to the substrate


22


along its outer edge


24


. The substrate


22


has an upper substrate surface


23


which is desirably continuous. The outer edge


24


may have any shape. In this embodiment, the pointing device


10


is generally circular and symmetrical, and the outer edge


24


is substantially circular in shape. The substrate surface


23


typically is substantially parallel to a plane defined by the opening


16


of the upper chassis


18


, but may be nonparallel thereto. It is understood that the upper chassis


18


is not necessary for the proper operation of the pointing device


10


, but is provided to conveniently define a contact area for the digit.




As best seen in

FIGS. 3



a


and


3




b


, the orb controller


12


has a protruded portion or boss


26


opposite from the control surface


14


. The orb controller


12


desirably has a substantially annular wing


27


which can serve as a mechanical stop with the chassis


18


to limit the range of movement of the orb controller


12


, as best seen in FIG.


2


. The wing


27


is of course optional and can be eliminated. The orb controller


12


is substantially symmetrical with respect to a z axis, and is typically made of a polymer such as rubber or plastic.




Another embodiment of the orb controller


12


′ is shown in

FIG. 3



c


which includes an additional hump


29


on top of the control surface


14


. The hump


29


can be integrally formed with the remaining portion of the orb controller


12


′, or can be a separate component that is connected to the control surface


14


. The hump


29


has a curved surface


31


that may be substantially spherical. The curved surface


31


becomes the contact surface the digit or hand of the operator to operate the orb controller


12


′. The curved surface


31


of the hump


29


has a smaller curvature than the control surface


14


, and provides the sensation of a smaller ball for the digit or hand to operate the orb controller


12


′. In this embodiment, the control surface


14


may be more shallow with a lower profile than that of the embodiment shown in

FIG. 3



b


, so that the maximum height of the orb controller


12


′ remains small and approximately the same as the maximum height of the orb controller


12


of

FIG. 3



b


without the hump


29


.




The return member


20


is best seen in

FIGS. 4



a


and


4




b


, and is advantageously resilient. The return member


20


is substantially symmetrical with respect to the z axis at rest (FIG.


1


). The return member


20


includes a seat


28


having a cavity for receiving the boss


26


of the orb controller


12


. The boss


26


is shaped to cooperate in a fitted manner with the cavity of the seat


28


, as shown in the assembled device


10


of

FIGS. 1 and 2

. The return member


20


has sufficient resiliency to allow the boss


26


to fit into the cavity of the seat


28


to secure easily the orb controller


12


and the return member


20


together. This design also makes it convenient to separate the orb controller


12


from the return member


20


and replace the orb controller


12


.




The return member


20


has a conductive surface


30


disposed below the seat


28


. The conductive surface


30


is desirably curved with a substantially convex shape. An annular arch


32


connects the seat


28


to the outer edge


24


of the return member


20


. The annular arch


32


between the seat


28


and the outer edge


24


provides additional flexibility for the return member


20


to function as a non-spring return mechanism for the pointing device


10


. In the embodiment of

FIGS. 1-2

, the annular arch


32


is advantageously thinner than the other portions of the return member


42


. Other configurations such as an accordion-like structure (not shown) are possible. The separate orb controller


12


can isolate and insulate the user's hand from the electrical circuitry and components that include the conductive surface


30


of the return member


20


and the upper surface


23


of the substrate


22


. The boss


26


and seat


28


combination allows the thickness of the portion of the return member


20


adjacent the conductive surface


30


to be relatively thin. As a result, the return member


20


of the pointing device


10


tends to deform and reform more smoothly and reliably. Other configurations of the return member for resiliently supporting the conductive surface


30


relative to the substrate surface


23


, such as those that employ springs, are possible.




The resilient return member


20


is electrically conductive, at least at the conductive surface


30


, which is spaced from the substrate surface


23


of the substrate


22


in the neutral, undeflected state shown in FIG.


1


. An electrical voltage is applied to the return member


20


to produce an energizing voltage therein. The voltage can be produced by any method known in the art. For example, the voltage can be created by electrically contacting the return member


20


(or at least the conductive surface


30


) with one or more electrical conductors or contacts (not shown) spaced along its outer edge


24


. In applications where the pointing device


10


is used with microprocessors, the typical voltage applied to the return member


20


is about 3-5 volts. The voltage can be different for other applications.




The conductive surface


30


is resiliently supported by the substrate


22


along the outer edge


24


to be movable or displaceable between the undeflected mode shown in FIG.


1


and the deflected mode shown in FIG.


2


. In the deflected mode, the conductive surface


30


is pressed in the direction of the arrow


38


to make contact with the upper surface


23


of the substrate


22


to form a contact location


40


. The convex conductive surface


30


rocks on the substrate surface


23


of the substrate


22


in the deflected mode. As the conductive surface


30


rocks on the substrate surface


23


of the substrate


22


, the contact location


40


between the conductive surface


30


and the substrate surface


23


is changed.




The substrate


22


in this embodiment is substantially planar and circular, but other shapes are possible. The substrate surface


23


of the substrate


22


has circuit paths or conductive lines and resistive coatings formed thereon or embedded therein or otherwise provided on the surface. Various analog/digital circuitry patterns that can be formed on the upper surface


23


of the substrate


22


are known in the art and are not described herein. In this embodiment, the return member


20


advantageously encloses the substrate surface


23


and protects the circuitry on the substrate surface


23


from the external environment.




The pointing device


10


has a height that is preferably smaller than, and more preferably substantially smaller than, a joystick. When assembled in the rest mode (FIG.


1


), the maximum height of the control surface


14


from the substrate surface


23


is a function of the size of the pointing device (such as the area of the substrate surface


23


and size of the return member


20


). For a substantially circular substrate surface


23


defined by the outer edge


24


of the return member


20


, one possible criterion can specify the maximum height of the control surface


14


at rest as a function of the diameter of the substrate surface


23


. For example, the maximum height can be set at about 0.5-1.5 times, and more desirably about 0.8-1.2 times, the diameter of the substrate surface


23


. In a typical application, the maximum height is desirably less than about 25 mm, and more desirably about 13-15 mm. To control the maximum height to within the specified range, one can provide a thin orb controller


12


with a short boss


26


and/or a thin return member


20


with the conductive surface


30


spaced from the substrate surface


23


by a small minimum clearance in the undeflected mode. For instance, a moderately convex control surface


14


will produce a thinner orb controller


12


than a steep control surface


14


, while a moderately convex conductive surface


30


will also produce a thinner return member


20


than a steep conductive surface


30


. In one embodiment, the orb controller


12


has a circular dome-like or disc-like shape with a maximum diameter, and a maximum thickness of less than about 0.5 time, and more desirably less than about 0.2 times, the maximum diameter. When the hump


29


is present (

FIG. 3



c


), its maximum thickness is less than about 0.2 times, and more desirably less than about 0.1 times, the maximum diameter. The hump


29


typically has a maximum thickness measured from the control surface


14


of less than about 0.5 times the maximum overall thickness of the control member


12


. The minimum clearance between the conductive surface


30


and the substrate surface


23


in the undeflected mode is typically less than about 1 mm, and more desirably less than about 0.5 mm.




In operation, when the orb controller


12


is pressed downward, the resilient return member


20


is deflected toward the substrate


22


. The deflection causes the conductive surface


30


of the return member


20


to engage the upper surface


23


of the substrate


22


and make electrical contact therewith at the contact location


40


, as best seen in the illustrated deflected mode in FIG.


2


. The rocking motion created between the conductive surface


30


and substrate surface


23


causes the orb controller


12


as well as the return member


20


to rotate. The rotation of the control surface


14


eliminates the need to rotate the joint of the digit when manipulating the orb controller


12


to move in the east/west direction (as well as other substantially lateral directions). As a result, the possibility of repetitive stress disorders and pain is greatly reduced. The orb controller


12


has a much lower physical profile (height) than a joystick, and overcomes the stress problems associated with a control pad. Therefore, the pointing device


10


is more versatile and safe to use.




The conductive surface


30


of the return member


20


is biased with an applied voltage. The circuitry pattern on the substrate surface


23


has electrical contacts (digital) that are closed when an external force is applied. Signals so developed are supplied, for instance, to a microcontroller (not shown) to wake up the microcontroller and/or to inform the microcontroller of the direction and speed of the movement caused by the external force. The larger the displacement of the orb controller


12


, the further out the contact location


40


is between the conductive surface


30


and the analog/digital circuitry on the substrate surface


23


. This produces a variable signal that is due to the angular displacement of the orb controller


12


. Furthermore, the corresponding increase in force on the orb controller


12


and return member


20


either increases the surface area of contact for a change in resistance, or changes the absolute point of contact


40


on the analog/digital contact on the substrate surface


23


, thereby changing the point of the voltage potential. This changes the analog voltage as detected on the substrate surface


23


. Using methods known in the art, the detected information can be used to calculate the contact location


40


between the conductive surface


30


of the return member


20


and the substrate surface


23


. The software in the microcontroller interprets the data relating to this change and directs an output to a relevant receiver that can be connected by a wire or similar structural members.




Upon release of all external forces on the orb controller


12


, the return member


20


moves back to its neutral position and the conductive surface


30


is again spaced from the substrate surface


23


(FIG.


1


). The material and geometry of the return member


20


are selected to facilitate repeated deformation and reformation of the return member


20


between the deflected and undeflected modes in a smooth and reliable manner. The resilient return member


20


, including the conductive surface


30


, may be made of low durometer rubber that is conductive. The return member


20


typically has a very low resistance, for instance, below about 500 ohms. The orb controller


12


may be made of the same material as the return member


20


. In other embodiments, the interior of the resilient return member


20


may be hollow or filled with a suitable filler such as plastic. These components of the pointing device


10


may be made by, for example, molding. In the embodiment shown in

FIGS. 1-4

, the orb controller


12


and return member


20


are separate components that are connected together to form the pointing device


10


. In other embodiments, the orb controller


12


and return member


20


may be made of the same material, and be integrally formed together. The components of the pointing device


10


can be made, for example, by molding.




It will be understood that the above-described arrangements of apparatus and methods therefrom are merely illustrative of applications of the principles of this invention and many other embodiments and modifications may be made without departing from the spirit and scope of the invention as defined in the claims. For instance, the return member


20


can be formed with a resistive surface instead of the conductive surface


30


, and the substrate surface


23


can include a conductive material without resistive coatings. In a specific embodiment, the return member


20


comprises a resistive material which is desirably a resistive rubber. The resistive rubber may include a resistive material, such as carbon or a carbon-like material, imbedded in a rubber material. The resistive rubber advantageously has a substantially uniform or homogeneous resistance. In most applications, the resistive rubber used has a moderate resistance below about 50 thousand ohms and more desirably below about 25 thousand ohms, for instance, between about 5,000 and 10,000 ohms.




In operation, a voltage variance is provided over the resistive surface, and desirably over the resistive return member


20


. The voltage variance can be produced by any method known in the art. For example, the voltage variance can be created by electrically contacting the resistive return member


20


with a plurality of electrical contacts (not shown) spaced along its outer edge


24


. There are at least two, and desirably four, such electrical contacts (east, west, north, south). Each pair of opposite electrical contacts are energized with a voltage potential. The voltage-potential-energized electrical contacts produce a voltage variance across the resistive surface of the resistive return member


20


. Details of a similar configuration are found in a co-pending application, Ser. No. 08/939,377, filed Sep. 29, 1997 and assigned to Varatouch Technology Incorporated, the assignee of the present application. The entire disclosure of this application is incorporated herein by reference. In addition, the conductive surface


30


may be coupled to the substrate surface


23


and pivots on the substrate


22


near a center area in another embodiment. Yet another embodiment employs a spring pivoting mechanism coupling the substrate


22


′ with the orb controller


12


in a manner similar to that described in U.S. Pat. No. 5,675,309.



Claims
  • 1. A pointing device comprising:a return member being resiliently supported on a substrate surface having an electrically conductive material, the return member having an electrically conductive surface which is spaced from the substrate surface in a first position; and a controller coupled to the return member for moving the return member between the first position and a second position where the electrically conductive surface makes contact with the substrate surface at a contact location, the controller having a disk-like shape with a convex control surface on which to place one or more human digits for manipulating the controller to move the return member between the first position and the second position and to rock the electrically conductive surface on the substrate surface to change the contact location, the convex control surface facing away from the substrate surface, the electrically conductive surface varying in shape during movement on the substrate surface.
  • 2. The pointing device of claim 1, wherein the electrically conductive surface is substantially convex.
  • 3. The pointing device of claim 1, wherein the controller has a substantially circular shape with a maximum diameter and a maximum thickness of less than about 0.2 times the maximum diameter.
  • 4. The pointing device of claim 3, wherein the substrate surface is substantially planar and circular with a substrate diameter and the control surface is spaced from the substrate surface in the first position by a maximum distance of less than about 1.5 times the substrate diameter.
  • 5. The pointing device of claim 1, wherein the control surface is spaced from the substrate surface by a maximum distance of less than about 25 mm in the first position.
  • 6. The pointing device of claim 1, further comprising a chassis spaced from the substrate surface and having an opening through which a portion of the control surface of the controller protrudes.
  • 7. The pointing device of claim 6, wherein the opening of the chassis is substantially circular.
  • 8. The pointing device of claim 6, wherein the electrically conductive surface has a center area which is spaced closest to the substrate surface in the first position, and the opening of the chassis is substantially aligned with the center area of the electrically conductive surface.
  • 9. The pointing device of claim 1, wherein the return member comprises a low durometer rubber.
  • 10. The pointing device of claim 1, wherein the return member has an outer edge which is connected to the substrate surface.
  • 11. The pointing device of claim 1, wherein the return member at least substantially encloses the substrate surface from external environment.
  • 12. The pointing device of claim 1, wherein the return member includes a flexible annular arch which resiliently supports the electrically conductive surface relative to the substrate surface.
  • 13. A pointing device comprising:an electrically conductive surface; means for supporting the electrically conductive surface relative to a substrate having a substrate surface with an electrically conductive material to move between a neutral position in which the electrically conductive surface is spaced from the substrate surface and a contact position in which the electrically conductive surface makes rolling contact with the substrate surface; and a dome-like controller coupled to the electrically conductive surface and having a convex control surface on which to place one or more human digits for manipulating the controller to move the electrically conductive surface between the neutral position and the contact position and to roll the electrically conductive surface on the substrate surface to change a contact location between the electrically conductive surface and the substrate surface, the convex control surface facing away from the substrate surface the electrically conductive surface varying in shape during movement on the substrate surface.
  • 14. The pointing device of claim 13, wherein the dome-like controller has a maximum diameter and a maximum height of less than about 0.5 times the maximum diameter.
  • 15. The pointing device of claim 13, wherein the control surface is spaced from the substrate surface in the neutral position by a maximum distance of about 13-15 mm.
  • 16. The pointing device of claim 13, wherein the substrate surface is substantially planar and circular with a substrate diameter and the control surface is spaced from the substrate surface in the neutral position by a maximum distance of about 0.8-1.2 times the substrate diameter.
  • 17. A pointing device comprising a control member including an electrically conductive surface facing a substrate surface having an electrically conductive material, the control member being resiliently supported on the substrate surface to move the electrically conductive surface on the substrate surface, the control member including a dome-shaped control surface on which to place one or more human digits for manipulating the control member to roll the electrically conductive surface on the substrate surface to change a contact location between the electrically conductive surface and the substrate surface, the convex control surface facing away from the substrate surface, the electrically conductive surface varying in shape during movement on the substrate surface.
  • 18. The pointing device of claim 17, wherein the control member is resiliently supported on the substrate surface to between from a contact position in contact with the substrate surface and a noncontact position away from the substrate surface.
  • 19. The pointing device of claim 17, wherein the electrically conductive surface has an area which is spaced closest to the substrate surface in the noncontact position by a distance of less than about 1 mm.
  • 20. The pointing device of claim 17, wherein the substrate surface is substantially planar and circular with a substrate diameter and the control surface is spaced from the substrate surface in the neutral position by a maximum distance of about 1.5 times the substrate diameter.
  • 21. The pointing device of claim 17, wherein the substrate surface includes a resistive coating.
  • 22. The pointing device of claim 17, wherein the electrically conductive surface of the control member includes a resistive material.
  • 23. The pointing device of claim 22, wherein the electrically conductive surface has a substantially uniform resistance.
  • 24. The pointing device of claim 22, wherein the control member comprises a resistive rubber material.
  • 25. The pointing device of claim 24, wherein the resistive rubber material comprises carbon or other conducting material embedded in rubber.
  • 26. The pointing device of claim 17, wherein the control surface includes a hump on which to place the human digit for manipulating the controller, the hump protruding from a center region thereof.
  • 27. The pointing device of claim 26, wherein the hump has an exposed curved surface which is smaller in curvature than the control surface.
  • 28. The pointing device of claim 26, wherein the hump has a maximum thickness measured from the control surface of less than about 0.5 times the maximum thickness of the control member.
  • 29. A pointing device comprising:a return member being resiliently supported on a substrate surface having an electrically conductive material, the return member having a dome-shaped electrically conductive surface which is spaced from the substrate surface in a first position; and a controller coupled to the return member for moving the return member between the first position and a second position where the electrically conductive surface makes contact with the substrate surface at a contact location, the controller having a disk-like shape with a dome-shaped convex control surface on which to place one or more human digits for manipulating the controller to move the return member between the first position and the second position and to rock the electrically conductive surface on the substrate surface to change the contact location, the convex control surface facing away from the substrate surface.
  • 30. The pointing device of claim 29, wherein the electrically conductive surface varies in shape during movement on the substrate surface.
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