Patent Publication Number: US-2013249808-A1

Title: System for implementing an overlay for a touch sensor including actuators

Description:
FIELD OF THE INVENTION 
     The field of the invention relates to touch sensors and mechanical overlays positioned over the touch sensor for providing interaction between a user and a host. 
     BACKGROUND OF THE INVENTION 
     Touch sensors are provided in communication with a host and allow a user to interact with the host without requiring the use of a pointing device such as a mouse. Typically touch sensors are transparent and are mounted on top of a display. Information is communicated from the host to the user via the display and the user is able to communicate information to the host via the touch sensor. For example, the host may present the user with a variety of options from which a selection can made; the options are presented to the user visually on the display; the user touches the touch sensor in the area where the desired option is displayed; and the user&#39;s selection is communicated to the host. Use of the display and touch sensor, therefore provide the user with an efficient user-friendly means for interacting with the host. 
     Touch sensors utilized today include, optical touch, resistive, surface acoustic wave (SAW), standard capacitive, and projective capacitive. Although a touch sensor overlaid on top of a display enables a user to interact directly with content rendered on the display, i.e. without the use of a pointer controlled by a mouse or touchpad, the contact surface of the touch sensor itself is a planar glass surface devoid of any details, features or reliefs that correlate with the rendered content on the underlying display. Accordingly, no tactile feedback is provided to the user when rendered content on the display is selected. The user&#39;s experience using the touch sensor system is thus suboptimal with respect to repetitive actions such as button or key activations in which tactile feedback is not provided. Although visual or audible feedback may be provided to the user in response to a touch, in many operating environments and applications of electronic devices, visual and audible feedback may be insufficient to signal changes in device state information and tactile feedback is the most effective form of feedback to the user. Furthermore, tactile feedback may be the only effective means to convey necessary device state information for a user that has visual or hearing impairments. 
     Currently mechanical overlays provide actuators which are used in connection with touch sensors to provide tactile feedback. Once the mechanical overlays are attached to the touch sensing system, however, the system designer must create unique software to provide for interaction between the mechanical overlay and the touch sensor. In the event, changes need to be made to the mechanical overlay, additional software must be written to provide for the interaction between the new mechanical overlay and the touch sensor. Unfortunately, this process is time consuming, cumbersome and adds costs to the system. 
     Accordingly, a need exists for a system which includes a mechanical overlay to provide tactile feedback to the user wherein the mechanical overlay can be readily implemented and modified by the system designer without requiring significant system modifications. 
     SUMMARY OF THE INVENTION 
     The present invention generally provides an improved system for implementing a mechanical overlay having actuators for interacting with the touch sensor and for providing tactile feedback. The actuators provide a footprint which is used to communicate with the host. The system further includes a configuration module which provides the system designer with the ability to readily implement and modify the mechanical overlay. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of the system of the present invention; 
         FIG. 2  is a cross-sectional view of a first embodiment of a portion of a mechanical overlay of the present invention which provides a push-type actuator; 
         FIG. 2   a  illustrates the footprint of the push-type actuator of  FIG. 2 ; 
         FIG. 3  is a cross-sectional view of a portion of a second embodiment of a mechanical overlay of the present invention which provides a slide-type actuator; 
         FIG. 3   a  illustrates the footprint of the horizontally-oriented slide-type actuator of  FIG. 3 ; 
         FIG. 3   b  illustrates the footprint of a vertically-oriented slide-type actuator; 
         FIG. 4  is a cross-sectional view of a portion of a third embodiment of a mechanical overlay of the present invention which provides a toggle-type actuator; 
         FIG. 4   a  illustrates a set of horizontal triangulary-shaped footprints of the toggle-type actuator of  FIG. 4 ; 
         FIG. 4   b  illustrates a set of vertical triangulary-shaped footprints of a toggle-type actuator; 
         FIG. 5  is a cross-sectional view of a portion of a fourth embodiment of a mechanical overlay of the present invention which provides a rotary-type actuator; 
         FIG. 5   a  illustrates a footprint of the rotary-type actuator of  FIG. 5 ; 
         FIG. 6  illustrates a touch sensor including a human touch zone and mechanical touch zones; 
         FIG. 7  illustrates a footprint of an actuator relative to the display; 
         FIG. 7   a  illustrates a footprint of an alternative actuator relative to the display; and 
         FIG. 8  is a flow diagram illustrating a typical operation of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     While the present invention is susceptible of embodiment in various forms, as shown in the drawings, hereinafter will be described the presently preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to specific embodiments illustrated. 
     As illustrated in  FIG. 1 , the system of the present invention generally includes a host  10 ; a display device  12  in communication with the host  10  via a display controller  14 ; a touch sensor system  15  including a touch sensor  16  in communication with the host  10  via a touch controller  18 ; and a mechanical overlay  20  in communication with the touch sensor  16 . A configuration module  24  is provided in communication with the host  10 . The configuration module  24  is a software program which is utilized by the host  10  to communicate with the controller  18 . The configuration module includes a configuration file  26  and an instruction set  34 . A memory  28  is provided in connection with the display controller  14  for storing information to be utilized by the display controller  14 . A memory  30  is provided in communication with the touch controller  18  for storing information to be provided to the touch controller  18 . Information stored by the memory  30  includes, for example, a library of footprints  32  and the configuration file  26  including the instruction set  34 . An auxiliary system  25  provides a user interface for defining the configuration file  26  to be provided to the configuration module  24 . 
     The mechanical overlay  20  of the present invention may take many forms depending upon the application for which it is used. Each mechanical overlay  20  includes a base, at least one actuator and a touch-generating member for providing interaction between the user and the host  10 . 
     First, second, third and fourth embodiments of the mechanical overlay  20  are illustrated in  FIGS. 2-5 . 
     A first embodiment  50  of the mechanical overlay mounted over the touch sensor  16  is illustrated in  FIG. 2 . The mechanical overlay  50  provides a push-type mechanical actuator  52  for use in connection with the touch sensor  16 . The actuator  52  generally includes a base  54  and an activation member  56 . The touch sensor  16  is generally rectangularly-shaped and includes opposite first and second edges  16   a,    16   b;  opposite third and fourth edges (not shown); and an upper surface  16   e.  The base  54  supports the activation member  56  over the upper surface  16   e  of the touch sensor  16 . The base  54  generally includes legs  54   a,    54   b  which are positioned proximate opposite first and second edges respectively of the touch sensor  16  and a platform  60  which extends between the legs  54   a,    54   b.  A gap  61  is provided between the upper surface  16   e  of the touch sensor  16  and the lower surface of the platform  60  of the base  54 . The activation member  56  is generally cylindrically-shaped and includes a downwardly extending central post  70 . The post  70  extends through an aperture  82  of the base  54 . A touch-generating member  72  is mounted to the lower end of the post  70 . The touch-generating member  72  is generally ring-shaped and preferably formed from a conductive dielectric material. A coil spring  74  is positioned around the post  70 . A gap  78  is provided between the lower end of the activation member  56  and the upper surface of the base  54 . In addition a gap  80  is provided between the touch-generating member  72  and the upper surface  16   e  of the touch sensor  16 . A retaining ring  84  extends around the activation member  56  and is mounted to the platform  60  of the base  54 . Engagement between the activation member  56  and the retaining ring  84  serves to retain the activation member  56 . 
     The activation member  56  is moveable from a rest position (i.e. a non-touch conveying state as illustrated in  FIG. 2 ) to an activated position (i.e. a touch conveying state, not shown) upon application of an activation force by the user. Activation force is provided when a user provides a perpendicular force relative to the touch sensor  16  to the activation member  56 . Upon providing this force, the spring  74  is compressed and the activation member  56  is moved toward the upper surface  16   e  of the touch sensor  16 . As the activation member  56  moves, the gap  80  between the touch member  72  and the upper surface  16   e  of the touch sensor is decreased. In addition, as the activation member  56  is moved toward the activated position, the lower end of the activation member  56  is moved toward the platform  60  of the base  54  decreasing the gap  78 . Downward movement of the activation member  56  is restricted by the contact between the lower end of the activation member  56  and the platform  60 . 
     The activated position of the activation member  56  is reached when the touch-generating member  72  contacts the upper surface  16   e  of the touch sensor  16 . Further, in the activated position, the member  72  provides a footprint on the touch sensor  16 . The ring-shaped footprint  77  provided by the touch-generating member  72  is illustrated in  FIG. 2   a . The footprint provides an inner edge  77   a  and outer edge  77   b.  A center point  77   c  is defined by the footprint  77 . The resolution of the touch sensor  16  is sufficient to recognize the ring-shaped footprint  77  provided by the member  72 . The footprint  77  created on the sensor  16  by the member  72  is utilized to select and implement instructions as will be discussed in more detail below. Although the member  72  has been illustrated as ring-shaped and results in the ring-shaped footprint  77 , the member  72  can be formed as desired to create virtually any desired footprint on the touch sensor  16 . Although the user&#39;s hand is in contact with the activation member  56 , due to the insulative properties of the activation member  56 , a path to ground is not provided from the touch member via the user. When the user releases the activation member  56 , spring  74  returns the activation member  56  to its resting position as illustrated in  FIG. 2 . 
     A second embodiment of the mechanical overlay  100  including a slide-type actuator  102  is illustrated in  FIG. 3 . The overlay  100  generally includes a base and the actuator  102 . 
     The base is mounted such that a platform  110  of the base extends over the sensor  16  and is spaced from the upper surface  16   e  of the sensor  16 . An aperture  112  is provided through the platform  110 . 
     The actuator  102  is generally T-shaped and includes an activation member  106  and a post  108  extending downwardly from the activation member  106 . A touch-generating member  114  is mounted to the lower end of the post  108 . The post  108  of the actuator  102  extends through the aperture  112  of the platform  110 . The activation member  106  of the actuator  102  rests on the upper surface of the platform  110 . The actuator  102  and base are sized and positioned to provide constant contact between the touch-generating member  114  and the touch sensor  16 . 
     Preferably, the touch-generating member  114  is rectangularly-shaped and provides a footprint  116  as illustrated in  FIG. 3   a . The touch-generating member  114  may be vertically-orientated (i.e. having a height greater than its width) to provide the footprint  116  illustrated in  FIG. 3   a . The vertically-oriented member  114  preferably is used in connection with the slide-type actuator  102  which slides in a horizontally-orientated aperture  112 , i.e. left-right relative to the user. 
     Activation of the actuator  102  occurs when the user grasps the activation member  106  and slides the actuator  102  within the aperture  112  and in a plane parallel with the upper surface  16   e  of the touch sensor. As the actuator  102  is slid within the aperture  112 , the touch-generating member  114  is slid on the surface of the touch sensor  16  to provide sliding activation of the touch sensor  16 . 
     Alternatively the touch-generating member  114  may be horizontally-oriented (i.e. having width greater than its height) to provide the footprint  118  illustrated in  FIG. 3   b . The horizontally-oriented touch-generating member having the footprint  118  can be used in connection with a slide-type actuator  102  which slides in a vertically-orientated aperture, i.e. up and down, if the display is positioned vertically, for example, on a wall or toward and away from the user, if the display is positioned in a table-top fashion. 
     Each touch-generating member  114  provides a unique footprint on the touch sensor  16  which is used to select and implement instructions as will be described herein below. 
     A third embodiment of the mechanical overlay  130  including a toggle-type actuator  132  is illustrated in  FIG. 4 . The overlay  130  generally includes a base and the actuator  132 . 
     The base includes a platform  136  positioned over the touch sensor  16 . The platform  136  is spaced from the touch sensor  16 . An aperture  137  is provided through the platform  136 . 
     The actuator  132  includes an activation member  138  and a centrally located pivoting member  140 . The activation member  138  is generally block-shaped and includes first and second off-set portion  142 ,  144 . The actuator  132  is positioned within aperture  137  of the platform  136  and is pivotally mounted to the platform  136  via the pivoting member  140 . A first touch-generating member  146  is mounted to the lower end of the first portion  142  and a second touch-generating member  148  is mounted to the lower end of the second portion  144 . The actuator  132  and base are sized and positioned to provide contact between either the first touch-generating member  146  and the touch sensor  16  or the second touch-generating member  148  and the touch sensor  16 . The touch-generating members  146 ,  148  are triangularly-shaped. 
     The toggle-type actuator  132  includes touch-generating members  146 ,  148  which make alternating contact with the touch sensor  16 . If the first touch-generating member  146  is in contact with the touch sensor  16  in the rest position, activation of the toggle-type actuator  132  occurs when the user applies an activation force to the second portion  144  thereby rotating the activation member  138  about the pivoting member  140  until the second touch member  148  contacts the sensor  16 . Upon rotating the activation member  138  about the pivoting member  140 , the first touch-generating member  146  will be removed from contact with the touch sensor  16  and the second touch-generating member  148  will come in contact with the touch sensor. The toggle type actuator  132  may include a spring to return the activation member  138  to the rest position upon release of the activation force by the user. Alternatively, the toggle-type actuator  132  may provide that the second touch-generating member  148  remains in contact with the touch sensor  16  until the user applies an activation force to the first portion  142  thereby rotating the activation member  138  about the pivoting member  140  until the first touch member  146  contacts the sensor  16 . 
     As noted above, each touch-generating member  146 ,  148  provides a footprint on the touch sensor  16 . The right and left pointing triangular footprints  150 ,  152  provided by the touch-generating members  146 ,  148  are illustrated in  FIG. 4   a . Specifically, the footprint  150  is provided by the touch-generating member  146  and the footprint  152  is provided by the touch-generating member  148 . The footprints  150 ,  152  are generally horizontally-orientated and relate to the toggle-type actuator  132  which generally pivots to provide a right/left rocking motion. The orientation of the members  146 ,  148  and related footprints  150 ,  152  represent the opposite directions of rotation of the activation member about the pivoting member  140 . Any number of conventions, however may be selected and utilized. For example, if the toggle-type actuator  132  is mounted to the base to provide pivoting in a manner that provides an up/down rocking motion, the touch-generating members may be configured to provide the upwardly and downwardly pointing triangular footprints  154 ,  156  illustrated in  FIG. 4   b . The footprints  146 ,  148 ,  154 ,  156  provided on the sensor  16  are utilized to select and implement instructions as will be described herein. 
     A fourth embodiment of the mechanical overlay  160  including a rotary-type actuator  162  is illustrated in  FIG. 5 . The overlay  160  generally includes a base and the actuator  162 . 
     The base includes a platform  166  positioned over the touch sensor  16 . The platform  166  is spaced from the touch sensor  16 . An aperture  168  is provided through the platform  166 . 
     The actuator  162  includes an activation member  170  and a post  172  extending downwardly from the activation member  170 . The activation member  170  is generally cylindrically-shaped. The post  172  of the actuator  162  is positioned within aperture  168  of the platform  166 . The lower surface of the activation member  170  rests on the upper surface of the platform  166 . A touch-generating member  174  is provided on the lower end of the post  172 . The touch-generating member  174  includes first and second portions  174   a,    174   b  which provide the footprint  178  illustrated in  FIG. 5   a . The first portion  178   a  of the footprint is centrally located and is provided by the centrally located portion  174   a  of the member  174 . The second portion  178   b  of the footprint  178  is radially located and is provided by the radially positioned portion  174   b  of the touch-generating member. The actuator  162  and base are sized and mounted to provided constant contact between the first and second portions  174   a,    174   b  of the touch-generating member  174  and the touch sensor  16 . 
     Activation of the actuator  162  is provided when the user grasps the activation member  170  and rotates the actuator  162 . As the actuator  162  is rotated, the off-centered, radially-positioned, second portion  174   b  of the touch-generating member moves along the path illustrated by the arrow  177  in either a clockwise or counter-clockwise direction. As the actuator  162  is rotated, the second portion  174   b  contacts different portions of the touch sensor  16  and provides information regarding the relative rotational position of the actuator  162  to the touch sensor  16 . Although the touch-generating member  174  has been described as having first and second portions,  174   a,    174   b,  alternatively, a single touch-generating member may be utilized in connection with the rotary-type actuator. The single touch-generating member includes an off-centered or radially positioned portion which provides relative rotational position information to the touch sensor  16 . The footprint  178  provided on the sensor  16  determines the selection and application of instructions as will be described herein. 
     The amount of force that is required to move the activation members  56 ,  106 ,  138 ,  170  of the actuators  52 , 102 ,  132 ,  162  is dependent upon the specific construction of each actuator  52 , 102 ,  132 ,  162 . For example, the force required to move the activation member  56  of the overlay  50  from the non-touch conveying state to the touch-conveying state depends on the tension of the spring  74  and the size of the gap  80 . The range of motion and activation force needed to move the activation members  56 ,  106 ,  138 ,  170  is designed to simulate traditional actuator behavior. In some instances, traditional touch sensors provide multiple activation points under tight spacing constraints. When a user&#39;s finger drifts or slips from the intended activation point on the touch sensor, the user may miss the intended target and therefore a touch is not registered. Conversely, the user may touch an activation point located near the intended target resulting in an unintentional touch being registered. The activation force required by the actuators  52 , 102 ,  132 ,  162  mitigates missed or unintentional touches. In addition, each actuator  52 , 102 ,  132 ,  162  provides tactile feedback to the user to indicate that a touch has occurred. 
     The actuator  52 , 102 ,  132 ,  162  and base of each of the overlays described may be constructed from a variety of materials with different levels of opacity ranging from opaque to transparent. Any number of elements of the mechanical overlay  20  may be formed from opaque or transparent materials and positioned in order to provide the desired level of viewing of the display through the overlay  20  and touch sensor. Furthermore, it is possible to construct the actuators  52 , 102 ,  132 ,  162  and bases from material(s) that can dynamically change opacity based on interaction with the host  10 . 
     Although the touch-generating members  72 ,  114 ,  146 ,  148 ,  174  have been described as having specific shapes, it is to be understood that the touch-generating members  72 ,  114 ,  146 ,  148 ,  174  could be provided with virtually any shape. Further, the touch-generating member provided in connection with any particular actuator may be provided with any shape, i.e., the designer is free to select virtually any shaped member to be used in connection with any actuator. 
     No electrical connection or communication is provided to the mechanical overlay  20 . Thus, configuration of the touch sensor  16  for operation with the mechanical overlay  20  is provided by the touch sensor controller  18  via the configuration module  24  of the host  10 . More, specifically, an auxiliary system  25  provides a user interface to create the configuration file  26 . The configuration module  24  is a software program which receives the configuration file  26  and is utilized by the host  10  to communicate with the touch controller  18 . The configuration file  26  includes, for example, attribute information  33  to be applied to the touch sensor  16  and an instruction set  34 . The configuration file  26  may be provided to the touch sensor system  15  upon initialization. Alternatively, the configuration file  26  may be provided to the touch sensor system  15  upon request from the host  10 . In addition, the configuration file  26  may be updated upon request from the host  10 . 
     As illustrated from the discussion above, the mechanical overlay  20  may include a variety of different types of actuators. Although certain types of actuators have been described, it is to be understood that the overlay  20  may include other forms of actuators including, for example, a joy stick-style actuator. In addition, a single overlay  20  may include several actuators. The actuators of the mechanical overlay  20  may be classified in accordance with the type of contact the touch member provides with the touch sensor  16 , including intermittent contact, constant contact or an intermittent-constant hybrid. Intermittent contact actuators include, for example, the push-type actuator of  FIG. 2 . The touch member  72  of the push-type actuator  52  is in contact only so long as the user applies the activation force to the actuator  52 . Continuous contact actuators include, for example, the slide-type actuator  102  and the rotary-type actuator  162 . Hybrid contact actuators include, for example, the toggle-type actuator  132 . 
     The mechanical touch provided by the mechanical actuators  52 ,  102 ,  132 , and  162  and the associated touch-generating members  72 ,  114 ,  146 ,  148 ,  174 , act as a proxy for a human touch. Often, the system designer may desire to incorporate human touch and mechanical touch simultaneously. To accommodate these designs, the system designer utilizes the configuration module  24  to configure the touch sensor to include multiple touch zones within the active area of the touch sensor. A diagram of an active area  188  of a touch sensor  16  including multiple touch zones is shown in  FIG. 6 . The active area  188  of the touch sensor  16  has been defined to include a first mechanical zone  192  and a second mechanical touch zone  194 . The remainder of the active area  188  of the touch sensor  16  continues to serve as a human touch zone  190 . The auxiliary system  25  presents the system designer with a user-friendly interface which allows the system designer to create a configuration file  26  which defines the dimensions, location, and attributes of each mechanical touch zone  192 ,  194 . The configuration file  26  is provided to the configuration module  24 . Upon initialization of the touch sensor system  15  or upon request from the host  10 , the configuration file  26  is provided to the touch controller  18  wherein the dimensions, location, and attributes of each mechanical touch zone are implemented. 
     The mechanical overlay  20  is sized and positioned to allow one or more touch-generating members to contact the mechanical touch zone(s)  192 ,  194  of the touch sensors  16  and to provide access to the human touch zone  190  so that the user may utilize the human touch zone  190  in accordance with normal operations, i.e. by touching the touch sensor in this zone with his/her hands or fingers. Once the size and location of the touch zones have been defined, the attributes of each zone can be defined. Attributes in each zone of the touch sensor  16  are defined via the auxiliary system  25  and are provided in the configuration file  26 . The configuration file  26 , including the attribute information  33  is provided to the configuration module  24 . Upon initiation of the touch sensor system  15  or upon request from the host  10 , the defined attributes of the configuration file  26  are implemented by the touch sensor system  15 . 
     One attribute which the designer may want to define relates to a touch registration threshold. When a capacitive touch sensor  16  is utilized, for example, the alteration to the electric field of the capacitive touch sensor caused by the mechanical touch provided by the actuators  52 ,  102 ,  132  and  162  is generally less dramatic than the alteration to the electric field caused by a human touch. The system designer may, through the auxiliary system  25  set the touch registration threshold for each defined zone of the touch sensor through the configuration file  26 . Due to the difference in the intensity of the alteration to the electric field provided by the human touch versus the mechanical touch of the mechanical actuator, the designer may set the touch registration threshold for a mechanical touch zone at a lower level than the touch registration threshold for a human touch zone. The defined touch registration thresholds for each zone may be included within the attribute information  33  of the configuration file  26 . The configuration file  26  is provided to the configuration module  24  and upon initialization of the touch sensor system  15  or upon request from the host  10 , the touch registration threshold information is applied to the touch controller  18 . 
     Another attribute of each zone which may be defined utilizing the configuration module  24  is the calibration/recalibration of each zone. A capacitive touch sensor, for example is designed to identify changes in the electric field associated with the sensor when compared to a “normal” state of the electric field. Traditionally, the electric field associated with the touch sensor is periodically recalibrated, i.e. a new normal state is determined, to account for environmental factors which affect the electric field. This recalibration allows a touch to be more readily identified and distinguished from other factors which may affect the electric field. As described above, the touch provided by a mechanical actuator affects a capacitive sensor  16  differently than a human touch. The auxiliary system  25  presents the system designer with a user friendly interface for defining the calibration/recalibration of each zone. This calibration/recalibration information for each touch zone is included in the attribute information  33  of the configuration  26  which is provided to the configuration module  24 . Upon initialization of the touch sensor system  15  or the upon request from the host  10 , the attribute information  33  including the calibration/recalibration information is applied to the touch controller  18 . 
     Another attribute of the touch sensor  16  which may be defined utilizing the configuration module  24  is auto-normalization/nulling. Auto-normalization/nulling is traditionally used with a capacitive touch sensor to recalibrate the sensor upon experiencing a “static” touch. For example, if a metal object comes in contact with a traditional capacitive touch sensor, the contact will initially be registered as a touch. However, if the object remains stationary for a period of time, the touch sensor identifies the change as a “permanent” change, i.e. one not related to a touch. In this situation, traditionally, the electric field of the touch sensor is recalibrated so that the electric field including the contacting metal object becomes the new “normal”. By doing so, the touch sensor can continue to effectively respond to dynamic touches on the touch sensor. Because certain mechanical actuators, e.g. the slide-type actuator  102  or the rotary-type actuator  162 , for example, provide continuous contact with the touch sensor  16 , and others provide a hybrid contact with the touch sensor  16 , as with the toggle-type actuator  132 , if a capacitive touch sensor is to be implemented, deactivation of the auto-normalization feature of the touch sensor  16  in the mechanical touch zone is required in order for the touch sensor to continue to effectively respond to contact between the touch member of these mechanical actuators and the sensor  16 . The auxiliary system  25  presents the system designer with a user-friendly interface for defining use of auto-normalization of each zone of the touch sensor  16 , allowing this feature to be turned “on” or “off” in each zone as required by the user. Information relating to the use of auto-normalization is provided in the attribute information  33  of the configuration file  26  via the auxiliary system  25 . The configuration file  26  including the auto-normalization attribute information  33  is provided to the configuration module  24  and upon initialization of the touch sensor system  15  or upon request from the host  10 , the auto-normalization attribute information  33  is applied to the touch controller  18 . 
     As described above, several attributes of the touch sensor can easily be modified or defined by the system designer utilizing the configuration module  24  and the configuration file  26 . In addition to the attributes mentioned above, the configuration module  24  and the attribute information  33  of the configuration file  26  may be utilized to define virtually any attribute of sensor which is controlled by the controller  18 . For example, attribute information  33  may include start-up calibration settings, active calibration settings, etc. 
     As discussed above, each mechanical actuator  52 ,  102 ,  132 ,  162  includes a touch-generating member  72 ,  114 ,  146 ,  148 ,  174  which provides a unique, pre-defined footprint  77 ,  116 ,  118 ,  150 ,  152 ,  154 ,  156 ,  178  to the touch sensor  16 . The unique, pre-defined footprints are stored in the library of footprints  32  of the controller  18 . The resolution of a touch sensor  16  is sufficient to recognize these unique footprints. In the case of a capacitive touch sensor, for example, when the footprint of an actuator makes contact with the touch sensor  16  within a mechanical touch zone, the controller  18  provides a gradient map of the electric field to identify the footprint. Once the footprint has been identified, the controller  18  utilizes shape recognition to query a library of pre-defined footprints  32  to identify the footprint provided on the sensor  16 . Alternatively, the library of pre-defined footprints  32  may be provided on the host  10 . In this instance, data is provided from the touch sensor  16  to the host  10  and the host  10  performs the function of identifying the footprint provided on the sensor  16 . 
     The auxiliary system  25  provides a user-friendly interface through which the system designer may create and store the instruction set  34  via the configuration file  26 . The instruction set  34  provided in the configuration file  26  includes instructions associated with each actuator footprint. Because each type of mechanical actuator includes a unique pre-defined footprint, once the footprint is recognized by the controller  18 , the instructions associated with the recognized footprint may be implemented. These instructions relate to a wide range of interactions between the overlay  20 , the actuators  52 ,  102 ,  132 ,  162 , the controller  18 , and the host  10 . 
     The instructions may be defined, for example, to convey state information. Similar to conventional mechanical actuators, the actuators of the mechanical overlay  20  may convey state or change of state information to the host  10 . When a conventional push-type actuator is depressed, for example, device state information is communicated to the host, i.e. the information provided may indicate that that the state of the device is to be changed either from ON to OFF or from OFF to ON. The present invention provides similar state information when the push-type actuator  52  is provided in the mechanical overlay  20 . The auxiliary system  25  includes a user-friendly interface which the system designer utilizes to define instructions for the push-type actuator in order to convey state information to the host  10 . The system designer may, for example, establish that in the first instance in which the push-type actuator  52  is actuated, the controller  18  will provide state information to the host  10  indicating that a device is in an ON state and that subsequent activation of the push-type actuator  52  will result in toggling between states ON and OFF. Alternatively, the system designer may, for example, establish that in the first instance in which the push-type actuator  52  is actuated, the controller  18  will provide state information to the host  10  indicating that a device is in an OFF state and that subsequent activation of the push-type actuator  52  will result in toggling between states OFF and ON. The instructions to be utilized are stored within the instruction set  34  of the configuration file  26  and provided to the configuration module  24 . 
     As noted above, the push-type actuator  52  includes a ring-shaped touch-generating member  72 . When the actuator  52  is activated, the footprint  77  of the member  72  is recognized by the controller  18  as ring-shaped. The controller  18 , via the library of shapes  32 , identifies the actuator  52  as a push-type actuator and as a result the instructions of the instruction set  34  associated with the push-type actuator  52  are selected and implemented via the controller  18 . Thus, if the system designer desires that the first instance of activation of the push button relates to a device “ON” state, the instruction set  34  of the configuration file  26  will provide instructions that upon activation of the actuator  52 , the controller  18  will provide information to the host  10  indicating that the related device is to be provided an “ON” state command. Because a push-type actuator  52  is utilized to toggle between “ON” and “OFF” states, in order to provide an indication of the new state to the host  10 , the current state must be known. The current state information can be stored within the memory of the controller  18  or may be stored in the host  10 . In the event, the state information is provided within the controller  18 , the amount of processing required by the host system  10  is reduced. 
     In prior art systems employing mechanical actuators, the location of the touch provided by the mechanical actuator provides an indication to the host  10  as to which device the actuator state information relates. For example, if an actuator at a first location is activated, then the state information for a first device is to be updated. If however, an actuator at a second location is activated, then the state information for a second device is to be updated. With the present invention, however, because each actuator is provided with a uniquely-shaped touch-generating member and therefore a uniquely-shaped footprint, the location of the actuator is not necessary to identify the device to which the state information relates. Rather, the actuator  52  is associated with the device via the unique footprint. Thus, upon identification of the footprint, the controller  18  determines the device to which the state information is to be applied. In the event multiple actuators having the same footprint are utilized, location information may be provided to the host  10 , to distinguish the actuators. 
     In addition to communicating actuator state information, the instruction set  34  may be defined to trigger activity on the display. For example, upon recognition of the footprint associated with a push-type actuator  52 , the controller may be configured to trigger the change of content rendered on the underlying display  12 . If desired, the change of content on the display  12  may be limited to a particular portion(s) of the display. The dimensions of the portions of the display to be provided with updated content may be associated with the actuator footprint.  FIG. 7  illustrates the display  12  positioned under the touch sensor  16  and the position of the associated actuator footprint  77 . Dashed lines  77   a  and  77   b  illustrate the respective positions of inner edge  77   a,  and outer edge  77   b  of the footprint  77  provided by the touch-generating member  72  relative to the display  12 . The instruction set  34  includes an instruction to define the dimensions of a portion(s) of the display  12  associated with the footprint  77  provided on the overlaying touch sensor  16 . The instruction set  34  further includes an instruction to determine the location of these footprint associated display portions based upon the location of the footprint  77  on the touch sensor  16 . 
     For example, a first portion  90  of the display  12  associated with footprint  77  is circularly-shaped and defines a center point  92 . The radius of the first portion  90  is defined such that the circumference of the first portion  90  is the same as the circumference of the inner edge  77   a  of the footprint  77  on the overlaying touch sensor  16 . A second portion  94  of the display  12  is also associated with the footprint  77 . The second portion  94  is ring-shaped, including an inner edge  94   a  and an outer edge  94   b  and defining a center point  94   c.  The radius of the inner edge  94   a  of the second portion  94  is greater than the radius of the outer edge  77   b  of the footprint on the overlaying touch sensor  16 . The radius of the outer edge  94   b  of the second portion is defined to provide the desired dimensions of the second portion. In the event elements of the actuator  52  are transparent allowing viewing of additional portions of the display, the dimensions of the second portion  94  may be defined such that the second portion  94  extends under the actuator  52 . 
     The position of an actuator edge is illustrated by the line  85  and may correspond, for example, with the outer edge of the retaining ring  84  illustrated in  FIG. 2 . In the event the retaining ring  84  is provided by an opaque material, the portion of the display positioned under the retaining ring  84  will not be viewable. A “keep-out” zone  99  therefore extends from the inner edge  77   a  of the footprint  77  to line  85 . This keep-out zone  99  defines the area of the display relative to the footprint  77  which is not visible through the actuator  52 . The instruction set  34  may include instructions to define the keep-out zone  99 . 
     The instruction set  34 , therefore includes instructions to define the dimensions of the portions  90 ,  94  and the keep-out zone  99  relative to the footprint  77 . Once the display portions  90 ,  94  and the keep-out zone  99  have been defined, upon initialization of the touch sensor or upon request from the host, the location of the footprint on the touch sensor  16  is utilized to determine where on the display  12  the portions  90 ,  94  and the keep-out zone,  99  will be located. For example, the center point  92  of the first portion  90  may be aligned with the center point  77   c  of the footprint  77  to align the first portion  90  within the footprint  77  of the actuator  52 . If the actuator  52  or elements of the actuator  52  are transparent, content displayed on the first portion  90  of the display is visible through the actuator  52 . The center point  94   c  of the second portion may also be aligned with the center point  77   c  of the footprint  77  to align the second portion  94  around the footprint  77  of the actuator  52 . Content displayed on the second portion  94  of the display  12  is visible around the footprint and/or actuator  52 . For example, if the radius of the outer edge  94   b  of the second portion is selected to be 3 mm greater than the radius of the inner edge  94   a , a 3 mm wide ring will be provided around the footprint  77  within which content may be displayed. The keep-out zone  99  may also be aligned with the center point  77   c  of the footprint  77 . 
     The instruction set  34  may further include instructions which trigger the content to be updated in the first and/or second portion  90 ,  94  of the display  12  upon activation of the actuator  52 . The system designer can therefore provide an update to portions  90 ,  94  of the display  12  associated with the actuator  52 . The content displayed may include an icon/image, for example, the SPIN icon illustrated in  FIG. 7 . Alternatively, the content displayed may simply provide for the color of the portion  90  of the display  12  to change. The content provided to the second portion  94  of the display may also include an icon/image or may simply provide an update to the color of the display in the second portion  94 . By providing an instruction which defines the location of the keep-out zone  99 , an instruction may be provided in the instruction set  34  to prevent updates of content within the keep-out zone. 
     Although the portions  92 ,  94  are defined to lie within the footprint  77 , thereby aligning with the transparent portion of the actuator  52 , or to extend around the footprint  77 , thereby aligning around the actuator  52 , the portions of the display to be associated with the actuator  52  may also be defined to extend under the footprint  77 . Although the first and second portions  90 ,  94  have been respectively described as circularly-shaped and ring-shaped, it is to be understood the portions of the display associated with the actuator and actuator footprint may be of essentially any dimensions to provide virtually any shape. 
       FIG. 7   a  illustrates the location of the footprint  178  of the rotary-type actuator  162  on the display  12 . As noted above, the footprint  178  is provided by a first portion  178   a  and a second portion  178   b.  The dimensions of a display portion  95  associated with the footprint  178  define an arrow-shaped display portion  95 . Upon initialization of the touch sensor  16  or upon request from the host  10 , the location of the footprint  178  on the touch sensor  16  is utilized to determine the location on the display  12  of the portion  95 . As illustrated in  FIG. 7   a , the portion  95  of the display  12  is directed radially outwardly from a center point  178   c  of the footprint  178  of the actuator  162 . Activation of the actuator  162  is provided by rotation of the actuator  162  as indicated by the arrow  175 , for example. The instruction set  34  may include instructions which provide that upon rotation of the actuator  162 , the arrow-shaped portion  95  is re-located. For example, upon rotation of the actuator  162 , portion  178   b  of the footprint is provided to a new location  178   b ′ and the display  12  is updated so that the arrow-shaped portion  95  is provided at the new position  95 ′ to provide an indication that the actuator  162  has been activated. 
     Because the dimensions of the portions  90 ,  94 ,  95  of the display are defined relative to the dimensions of the actuator footprints  77 ,  178  and the locations of the portions  90 ,  94 ,  95  are defined relative to the location of the footprints  77 ,  178  on the touch sensor  16 , the display portions  90 ,  94 ,  95  are positioned in and around the footprint  77 ,  178  regardless of where the actuator  52  is positioned within the overlay  20 . If, for example, the actuators  52 ,  162  are moved to new locations within the overlay  20 , the dimensions of the portions  90 ,  94 ,  95  remain, however, the new location of the actuator  52 ,  162  is provided to determine the location of the portions  90 ,  94 ,  95 . In doing so, the first portion  90  of the display will be aligned with the actuator  52  so that the portion  90  including the “SPIN” icon is viewable through the actuator  52  at the new location. Likewise, the second portion  94  of the display surrounding the actuator  52  at its new location provides a ring around the actuator  52 . Similarly, because the arrow-shaped portion  95  of the display is defined relative to the center point  178   c  of the footprint  178 , if the actuator  162  is moved to a new location within the overlay  20 , the arrow-shaped portion  95  of the display will remain aligned with actuator  162 . 
     In another example, the instruction set  34  provided to the controller  18  via the configuration module  24  may be utilized to communicate value information to the host  10 . For example, in connection with a slide-type actuator  102 , the base of the overlay  110  will dictate the range in which the actuator  102  can move based upon the dimensions of the aperture  112 . Traditionally, the controller was utilized to simply send “raw” i.e. location data to the host to identify the position of the actuator. The host was then used to calculate or convert the location information to a numeric value in a range, e.g. a value in the range 0-100. 
     In the present invention, the horizontal slide-type actuator  102  includes a touch-generating member  114  having a vertical rectangularly-shaped footprint  116 . Upon initialization, the footprint  116  of the member  114  is recognized by the controller  18  as a vertical rectangular shape; the controller  18 , via the library of shapes  32 , identifies the actuator  102  as a horizontal slide-type actuator and applies any instructions of the instruction set  34  that the system designer has associated with the horizontal slide-type actuator. The instruction set  34  may include for example, a defined range of directional motion through which the actuator  102  will move and a defined alpha numeric calibration. For example, the designer may provide that the actuator  102  will move in the left-right direction and that a first numeric value, for example 0, will be associated with a first/left end of the aperture and a second numeric value, for example 100, will be associated with the second/right end of the aperture. The instruction set  34  defined by the system designer may further provide that the range of values between 0 and 100 are to be associated with the range of locations between the first and second ends of the aperture. In this instance, the location information of the slide actuator within the aperture is provided to the controller  18  wherein the instructions of instruction set  34  are applied to determine the numeric value associated with the current position of the slide-type actuator. This associated numeric value is then provided to the host  10 . 
     The present invention may therefore be utilized to select and apply different value ranges and to communicate the value associated with the actuator position to the host  10 . For example, the system designer may through an instruction set  34  associate a star-shaped footprint with the range of values 0-100 and a triangularly-shaped footprint with the range of values 100-500. If an actuator having a star-shaped footprint is provided in contact with the touch sensor, the controller  18  will recognize the star-shaped footprint and send a numeric value to the host  10  based upon the range of values 0-100 and based upon the location of the actuator within the aperture. If an actuator having a triangularly-shaped footprint is provided in contact with the touch sensor  16 , the controller  18  will recognize the triangularly-shaped footprint and send a numeric value to the host  10  based upon the range of values 100-500 and based upon the location of the actuator within the aperture. 
     Examples of different types of instructions to be included in the instruction set  34  and which may be defined by the system designer are described above. It is to be understood that any number of instruction sets  34  may be defined by the system designer to define the communication and interaction between the actuator, the controller and the host. For example, an instruction set  34  may include instructions to send a command to the host to launch a computer program. 
     The instruction set  34  implemented via the configuration module  24  is provided in the configuration file  26  and includes the instructions to be associated with the variety of mechanical actuators. The configuration file  26  may be provided on the host  10 . Alternatively, the configuration file  26  may be provided to the touch controller  18  and stored in the memory  30  associated with the controller  18 . 
     A method  190  of setting up and operating the invention is illustrated in  FIG. 8 . The system designer begins at step  192  and utilizes the auxiliary system  25  to create a configuration file  26 . At step  194  the configuration file  26 , including the defined touch sensor attributes and the instruction set  34  is provided to the configuration module  24 . When the system is initialized, at step  202  the configuration module  24  uploads the configuration file  26  containing the defined attributes and instruction set  34  to the touch sensor system  15 . Next, at step  204  the touch zones of the touch sensor  16  are defined and the desired attributes are applied to each touch zone. At step  206  the touch controller  18  begins to scan for human or mechanical touches. At step  208 , the controller  18  determines whether a touch has been registered. If no touch has been registered, the process returns to step  206  wherein the controller continues to scan for a touch. If at step  208  the controller  18  determines that a touch has occurred, the controller at step  210  next determines whether the touch occurred in a mechanical touch zone. If at step  210  it is determined that the touch did not occur in a mechanical touch zone, at step  212  the touch is reported and processed as a human touch and the process returns to step  206  where the controller  18  scans for a touch. If at step  210  it is determined that the touch occurred in a mechanical touch zone, the controller  18  at step  214  identifies the actuator footprint. Next, at step  216  the library is queried to identify the instructions associated with the footprint and at step  220  the associated instructions are implemented. At step  220  for example, the actuator logic associated with the footprint is applied to set the actuator state. Alternatively or in addition, at step  220  information is provided to the host  10 , including the actuator state information, triggers to initiate an update/modification to the display content, actuator value information, or any other pre-defined information as determined by the implemented instructions. The process returns to step  206  wherein the touch sensor controller  18  again scans for touches. 
     The present invention provides several advantages. One advantage is the flexibility provided to the system designer. Because the implemented instructions for the actuators of the overlay  20  are implemented via the configuration module  24  and the configuration file  26 , the instruction set  34  can be dynamically defined. For example, the instructions which provide calibration for a slide or rotary type actuator may initially provide a scale ranging from 1-100. If, however, the system designer wants to change the range of the scale to 1-50, the new range can be set through the configuration module  24 . In another example, the system designer may decide to change the design to implement a rotary-type actuator rather than a slide-type actuator. In this event, a new mechanical overlay may be provided with the rotary-type actuator. Because different instructions are associated with each footprint, upon identification of the footprint associated with the rotary-type actuator, the associated instructions for a rotary-type actuator will be implemented instead of the slide-type actuator. If the system designer has provided that the values previously associated with the slide-type actuator are also associated with the rotary-type actuator, implementation of the new rotary-type actuator is easily achieved. 
     The present invention allows the system designer to locate a mechanical overlay  20  with mechanical actuators providing tactile feedback anywhere over the active area of the touch sensor  16 . The system designer is also provided with the ability to readily change the location of the actuator(s). Because the footprint associated with the actuator is unique, the location at which the actuator provides input is not required in order to properly convey the actuator state information to the host. For example, if the host  10  anticipates state/logic information from a push-type actuator, the identification of the ring-shaped footprint provided by the push-type actuator is recognized by the controller  18 , and identifies the touch experienced by the sensor  16  as being derived from the push-type actuator. Thus, the location at which the touch is experienced is not required in order to convey the touch information to the host  10 . 
     The present invention, therefore, obviates the need for the system designer to define which type of actuators will be utilized, the location of the actuators and the instruction set for each actuator prior to each new product development. The ability of the system designer to make modifications via the auxiliary system allows the designer the ability to readily address market requirements or industrial design/ergonomic requirements as necessary. The implementation of mechanical actuators is therefore greatly simplified. 
     Previously, only the location of the actuator touch was provided to the host via the touch sensor and the actuator logic information was provided to the host via wires from the actuator. The software designer utilized this location information for processing and trigging events. If a change was made to the location of the actuator, for example, it was necessary to change the software to account for the new actuator location. Because the present invention allows for configuration of the mechanical overlay via the configuration module, changes to the overlay do not require changes to the software. e.g. regardless of the actuator location, if the controller  18  identifies the actuator&#39;s footprint, the proper state is conveyed to the host  10 , without any requirement that the software be modified. Using the example of the substitution of a rotary-type actuator for a slide-type actuator, the configuration module handles the conversion of the mechanical touch to an actuator value which is provided to the host. Because the host software simply receives and processes the actuator value information, a change to the actuator does not require changes to the host software. In short, the host software designer is not burdened with the actuator distinctions. Similarly, if the actuator is moved to a new location within the overlay  20 , the software designer is not required to revise the software in order to effectuate changes in the display which are triggered by the actuator and associated with the actuator. Because the instruction set defines actuator associated display areas utilizing the footprint of the actuator as a reference, no change in the software providing the update to the display content is necessary when a change in the location of the actuator occurs. The present invention, therefore, results in a reduction in the development costs including the cost of developing the host software and in turn enabling the product to get to market faster. 
     It is important to note that no additional wires and/or hardware are needed to implement the mechanical overlay  20 . Eliminating the hardware traditionally needed to define button logic translates into a significant cost reduction to the system designer. 
     The auxiliary system  25  provides a common interface which eliminates redundant customization/development activities for new product development. 
     While particular forms of the invention have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited except by the following claims.