Ergonomic pointing device

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.

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.

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. 3a and 3b, 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. 3c 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. 3b, 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. 3b without the hump 29.
 The return member 20 is best seen in FIGS. 4a and 4b, 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. 3c), 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.