# Patent

## Title
Haptic keyboard systems and methods

## Abstract

Various embodiments provide keyboards that utilize electrically-deformable material as an actuating mechanism to provide haptic feedback to a user of the keyboard. In at least some embodiments, the electrically-deformable material is utilized to impart, to a depressed key or keyboard element, a multi-vectored movement that produces a perceived acceleration of the key or keyboard element thus providing a user with haptic feedback which simulates a snapover movement. In at least some embodiments, a key or keyboard element can be associated with comparatively little or no actuation force and/or travel distance. As a result, the amount of work necessary to actuate the key or keyboard element can be significantly decreased or eliminated.

## Background
RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application No. 61/024,407, filed on Jan. 29, 2008, the disclosure of which is incorporated by reference herein in its entirety. This application is a continuation-in-part of and claims priority to U.S. application Ser. No. 11/945,879 filed on Nov. 27, 2007 now U.S. Pat. No. 7,741,979, which in turn claims priority to U.S. Provisional Application No. 60/948,377 filed on Jul. 6, 2007, the disclosures of which are incorporated by reference herein in their entirety.


BACKGROUND
Today, rapid typing keyboard technologies typically embody three primary attributes that are viewed as necessary or desirable for an effective implementation-low actuation force, significant travel distance, and tactile “snapover”.
With regard to a low actuation force, studies have found that in order for a user to rapidly type, it is desirable to provide an overall key top actuation force from around between 40-80 grams. Having a light actuation force permits easy actuation and reduces fatigue.
With regard to travel distance, in order to rapidly type, many current technologies provide an overall travel distance (i.e. the vertical distance a key travels) from between 2-4 millimeters. In technologies that implement keyboards using elastomeric domes that are collapsible under pressure for key actuation, the travel distance is required because of the physical and mechanical nature of the domes that are employed. Specifically, the physical structure of the dome requires a longer travel distance in order to allow the dome geometry to adequately collapse, thus providing a response with tactile characteristics that are necessary or desirable for rapid typing. In addition, this travel distance is important because as a key top moves relative to a finger, frictional forces of this relative movement provide an additional tactile element (i.e. localized skin stretching) that plays an important role in a user's recognition of an electronic switch closure. The travel distances required by current dome technology significantly limit the form factor, e.g. the thickness of an associated keyboard. That is, keyboard thickness is significantly limited by the use of dome technology. This, in turn, reduces keyboard construction potentials and the various environments in which such keyboards can be used.
With regard to the tactile snapover, such is an important aspect for rapid typing. A snapover, as will be appreciated by the skilled artisan, creates a specific tactile response which is desirable in typing scenarios, particularly those that are rapid typing scenarios. The notion of snapover refers to a relationship between force and travel and is defined as a specific area on a standard keyboard force displacement curve. Snapover is what users typically associate with a valid electronic switch closure. In addition, this association between the tactile response and an electronic switch closure allows the user to learn to not rely solely on visual confirmation during typing, such as looking at the screen between each typed letter, to ensure that they are typing correctly. In current rubber dome technologies, this snapover is achieved due to the collapsing of the rubber dome. Typically, force exerted on the key and hence, on the rubber dome increases until the dome collapses and achieves switch closure. Due to the geometry and the physical characteristics of the rubber dome, achieving a snapover effect requires a sufficient amount of force and travel to reach the snapover point.
Against the backdrop, a need remains for keyboards that provide adequate user feedback and address the three attributes mentioned above.
SUMMARY
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
Various embodiments provide keyboards that utilize an electrically-deformable material as an actuating mechanism to provide haptic feedback to a user of the keyboard. In at least some embodiments, the electrically-deformable material is utilized to impart, to a depressed key or keyboard element, a multi-vectored movement that produces a perceived acceleration of the key or keyboard element thus providing a user with haptic feedback which simulates a snapover movement.
In at least some embodiments, the electrically-deformable material is driven with a voltage responsive to a user depressing a key or keyboard element. In these embodiments, switch closure is first attained followed by the haptic feedback provided through the multi-vectored movement of the key or keyboard element. In at least some embodiments, the multi-vectored movement moves the key or keyboard element in at least a first direction, and then a second direction which is different from the first. Each of the directional movements is induced by its own driven voltage which is applied to different areas of the electrically-deformable material. In at least some embodiments, one of the directions of movement moves the key or keyboard element a distance which is greater than another of the directions of movement.
In a specific embodiment, a first direction of movement is generally toward the user and a second direction of movement is generally away from the user. In at least some embodiments, the first direction moves the key or keyboard element a distance which is less than a distance that the second direction moves the key or keyboard element. In one embodiment, the first direction moves the key or keyboard element a distance which is about half the distance that the second direction moves the key or keyboard element.
In at least some embodiments, multiple keys or keyboard elements can be grouped together into a logical grouping which is driven in a multi-vectored movement to provide haptic feedback. In this instance, each logical grouping constitutes a plate which is moved under the influence of the electrically-deformable material. In at least some embodiments, a keyboard can have single keys or keyboard elements that are driven under the influence of the electrically-deformable material, as well as logical groupings of keys or keyboard elements that are driven under the influence of the electrically-deformable material.
In at least some embodiments, the electrically-deformable material comprises an electroactive polymer or EAP. Other electrically-deformable materials can, of course, be used.
In at least some embodiments, a key or keyboard element can be associated with comparatively little or no actuation force and/or travel distance. As a result, the amount of work necessary to actuate the key or keyboard element can be significantly decreased or eliminated. In these embodiments, switch closure can be effectuated in response to a force applied to the key or keyboard element of about 80 grams or less and/or a travel distance of the key or keyboard of about 2.5 millimeters or less. The key or keyboard element can then be actuated upon switch closure by providing a multi-vectored movement to the key or keyboard element to achieve a tactile snapover effect.
In at least some embodiments, switch closure of a key or keyboard element can be effectuated in response to detecting an interaction. The interaction can be associated with a force applied to the key or keyboard element of about 80 grams or less and/or a travel distance of the key or keyboard of about 2.5 millimeters or less. For example, a user might depress the key or keyboard element, or simply place their finger proximate to it. The key or keyboard element can then be actuated upon switch closure.



BRIEF DESCRIPTION OF THE DRAWINGS
The same numbers are used throughout the drawings to reference like features.
FIG. 1 illustrates a top plan view of example key or keyboard element in accordance with one or more embodiments.
FIG. 2 illustrates the view of the FIG. 1 key or keyboard element, taken along line 2-2 in FIG. 1.
FIG. 3 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 4 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 5 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 6 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 7 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 8 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 8a is a circuit diagram in accordance with one or more embodiments.
FIG. 9 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 10 illustrates a system in accordance with one or more embodiments.
FIG. 11 illustrates an example keyboard in accordance with one or more embodiments.
FIG. 12 is a flow diagram that describes steps in a method in accordance with one or more embodiments.
FIG. 13 illustrates two force displacement curves in accordance with one or more embodiments.
FIG. 14 illustrates a key or keyboard element in accordance with one or more embodiments.
FIG. 15 is a flow diagram that describes steps in a reduced work method in accordance with one or more embodiments.



DETAILED DESCRIPTION
Overview
Various embodiments provide keyboards that utilize an electrically-deformable material as an actuating mechanism to provide haptic feedback to a user of the keyboard. Haptic feedback refers to feedback that is provided through movement related to touch.
In at least some embodiments, the electrically-deformable material is utilized to impart, to a depressed key or keyboard element, a multi-vectored movement that produces a perceived acceleration of the key or keyboard element thus providing a user with haptic feedback which simulates a snapover movement.
In at least some embodiments, the electrically-deformable material is driven with a voltage responsive to a user depressing a key or keyboard element. In these embodiments, switch closure is first attained followed by the haptic feedback provided through the multi-vectored movement of the key or keyboard element. In at least some embodiments, the multi-vectored movement moves the key or keyboard element in at least a first direction, and then a second direction which is different from the first. Each of the directional movements is induced by its own driven voltage which is applied to different areas of the electrically-deformable material. In at least some embodiments, one of the directions of movement moves the key or keyboard element a distance which is greater than another of the directions of movement.
In a specific embodiment, a first direction of movement is generally toward the user and a second direction of movement is generally away from the user. In at least one embodiment, the first direction moves the key or keyboard element a distance which is less than a distance that the second direction moves the key or keyboard element. In one embodiment, the first direction moves the key or keyboard element a distance which is about half the distance that the second direction moves the key or keyboard element.
In at least some embodiments, multiple keys or keyboard elements can be grouped together into a logical grouping which is driven in a multi-vectored movement to provide haptic feedback. In this instance, each logical grouping constitutes a plate which is moved under the influence of the electrically-deformable material. In at least some embodiments, a keyboard can have single keys or keyboard elements that are driven under the influence of the electrically-deformable material, as well as logical groupings of keys or keyboard elements that are driven under the influence of the electrically-deformable material.
In at least some embodiments, the electrically-deformable material comprises an electroactive polymer or EAP. Other electrically-deformable materials can, of course, be used.
In at least some embodiments, a key or keyboard element can be associated with comparatively little or no actuation force and/or travel distance. As a result, the amount of work necessary to actuate the key or keyboard element can be significantly decreased or eliminated. In these embodiments, switch closure can be effectuated in response to a force applied to the key or keyboard element of about 80 grams or less and/or a travel distance of the key or keyboard of about 2.5 millimeters or less. The key or keyboard element can then be actuated upon switch closure by providing a multi-vectored movement to the key or keyboard element to achieve a tactile snapover effect.
In at least some embodiments, switch closure of a key or keyboard element can be effectuated in response to detecting an interaction. The interaction can be associated with a force applied to the key or keyboard element of about 80 grams or less and/or a travel distance of the key or keyboard of about 2.5 millimeters or less. For example, a user might depress the key or keyboard element, or simply place their finger proximate to it. The key or keyboard element can then be actuated upon switch closure.
In the discussion that follows, a section entitled “Example Key or Keyboard Element” is provided and describes but one example of a key or keyboard element in accordance with one or more embodiments. Following this, a section entitled “Magnetically-Induced Snapover Effect” is provided and describes one example of how snapover effect can be achieved using a magnetic assembly. Following this, a section entitled “Drive Circuit” is provided and describes an example circuit that can be used as drive circuitry. Next, a section entitled “Detent Structure” is provided and describes an example detent structure that can be utilized to provide a snapover effect. A section entitled “Example System” is provided and describes a system that can be used in accordance with one or more embodiments. Next, a section entitled “Logical Key Groupings” is provided and describes how multiple different keys can be grouped together in accordance with one or more embodiments. Next, a section entitled “Example Method” is provided and describes a method in accordance with one or more embodiments. Next, a section entitled “Reduced Work Keys or Keyboard Elements” is provided and describes how keys or keyboard elements can be associated with comparatively little or no actuation force and/or travel distance. Finally, a section entitled “Example Reduced Work Method” is provided and describes a method in accordance with one or more embodiments.
Example Key or Keyboard Element
FIG. 1 illustrates an example key or keyboard element in accordance with one or more embodiments generally at 100. In this example, the key or keyboard element includes a frame 102 to which is mounted or otherwise connected to one or more sections of electrically-deformable material 104. Frame 102 is supported by an overall housing an example of which is provided below in FIG. 11. In the illustrative example, electrically-deformable material 104 comprises a single integral piece of material. It is to be appreciated and understood, however, that individual keys or keyboard elements can have multiple different sections of electrically-deformable material.
In at least some embodiments, the electrically-deformable material comprises an electro-active polymer or EAP. EAP refers to a class of polymers which are formulated to exhibit different physical, electrical, and/or electro-optical behaviors and properties. In general, when EAP is driven by an applied voltage, the EAP undergoes a deformation in a particular direction. This deformation causes the EAP to move in the particular direction. In this particular embodiment, the electrically-deformable material 104 is driven by one or more drive voltages to effect movement of an associated key or keyboard element. To this end, and in this embodiment, key or keyboard element 100 includes a center actuator 106 which is mounted to or otherwise joined with electrically-deformable material 104. Actuator 106, in turn, is fixedly connected to an associated key or keyboard element (not shown) which lies above the plane of the page upon which FIG. 1 appears.
Key or keyboard element 100 also includes one or more electrical contacts which are used to apply a drive voltage to electrically-deformable material 104. In the illustrated and described embodiment, first and second electrical contacts 108, 110 are provided and are in electrical communication with the electrically-deformable material 104. In turn, the first and second electrical contacts 108, 110 are connected with drive electronics which are used to apply a voltage to the contact and hence, cause deformation of the electrically-deformable material 104. Any suitable material can be used for contacts 108, 110. In the illustrated and described embodiment, the electrical contacts comprise a carbon material which is mounted to or otherwise joined with the electrically-deformable material.
FIG. 2 illustrates key or keyboard element 100 of FIG. 1 in a view that is taken along line 2-2 in FIG. 1. Like numerals from the FIG. 1 illustration have been utilized to depict like components. Here, the key or keyboard element 100 includes a user-engageable portion 202 which is the portion that is typically depressed by the user. The user-engageable portion may, for example, correspond to a particular key, such as the letter “A” key, a function key, a shift key, and the like. The user-engagable portion includes a surface—here a top surface—that is typically engaged by a user's finger.
In addition, key or keyboard element 100 includes a pair of switch closure elements 204, 206 forming a switch. The switch closure elements can be formed from any suitable material examples of which include non-tactile membranes that include electrically conductive materials. Other materials include, by way of example and not limitation, conductive elastomeric material, carbon material, piezo-membrane, capacitive sensing, capacitive sensing in combination with piezo sensing and piezo ink, to name just a few. In addition, the switch closure elements can be located at any suitable location within the keyboard element. For example, the switch closure elements can be located between portion 202 and underlying structure, on top of portion 202, or any other suitable location. The switch closure elements are connected to circuitry to detect switch closure.
In addition, in at least some embodiments, backlighting can be provided by virtue of one or more light sources mounted underneath the key or keyboard element. The light sources can be implemented using any suitable technology. By way of example and not limitation, light sources can be implemented using LEDs, light pipes using LEDs, fiber optic mats, and/or electroluminescent panels to name just a few.
In at least some embodiments, the electrically-deformable material is generally translucent, thus allowing light to pass through and illuminate the undersides of the keys. This can allow, for example, key legends to be illuminated for the user. In the past, backlighting keyboards has proven difficult due to the presence of various actuation structures such as domes and scissor mechanisms which tend to block light.
Referring to FIG. 3, when a user depresses key or keyboard element 100 in the direction shown, switch closure elements 204, 206 are brought into electrical communication (as indicated by the dashed oval) which closes a circuit thus indicating that a key or keyboard element has been depressed. Circuitry described below detects the depression event and causes drive electronics to apply one or more drive voltages (e.g., 500-5000) volts to the electrically-deformable material 104. The drive electronics can be configured in any suitable way. For example, in some embodiments, the drive circuitry can include switching circuitry that switches a low voltage side of a power supply on or off using, for example, one power supply per key or keyboard element. Inductive transformers or piezoelectric transformers can be used to generate sufficient voltage supplies, as will be appreciated by the skilled artisan. Alternately or additionally, various solid state devices can be used to switch power from a single voltage supply to individual EAP portions as required. One specific example of a circuit suitable for use is shown and described below in a section entitled “Drive Circuit”. Alternately or additionally, switching can be achieved using an application specific integrated circuit (ASIC) that contains a series array of solid state switch elements.
When the drive voltages are applied to the electrically-deformable material, multi-vectored movement is imparted to actuator 106 and hence, to portion 202.
Specifically, and as perhaps best shown in FIGS. 4 and 5, when a user depresses a key or a keyboard element sufficient to effect switch closure, the drive electronics drive the electrically-deformable material and hence, the key or keyboard element in a first direction which, in this example, is generally toward the user. In this example, the drive voltage is applied through electrical contact 110. Subsequently, the drive electronics, through electrical contact 108, drive the electrically-deformable material in a second, different direction. In this example, the second, different direction is generally away from the user. In at least some embodiments, the first direction moves actuator 106 a first distance and a second direction moves actuator 106 a second distance which is greater than the first distance. In at least some embodiments, the first distance is about half the distance of the second distance. In at least some embodiments, the first distance is about 1⁄2 millimeter and a second distance is about 1 mm.
The electrically-deformable material can, however, be operated in a “single phase” mode or a “dual phase” mode. In a single phase mode, when the material is electrically driven, the material moves the key or keyboard element in a desired direction. When the drive voltage is removed, the material returns to its original, starting position due to the resiliency of the material. In a dual phase mode, the material is driven as described above. Of course, multiple other phases can be used by driving the material to impart to it movements other than the “back and forth” movement described above.
Magnetically-Induced Snapover Effect
In at least some embodiments, movement of the key or keyboard element to provide a snapover effect is provided through a combination of the electrically-deformable material and a magnetic assembly comprising, in this example, a pair of opposed magnets that are mounted in the key or keyboard element structure.
As an example, consider FIG. 6. There, a key or keyboard element is shown generally at 600. Like numerals from the above-described embodiments are utilized to depict like components. Here, a magnet assembly 602 includes a first magnet 604 and a second magnet 606. First magnet 604 is seated or otherwise fixedly mounted to user-engageable portion 202. Second magnet 606 is mounted to electrically-deformable material 104. When a user depresses a key or keyboard element, a drive voltage is applied to the electrically-deformable material 104 sufficient to cause second magnet 606 to move in the direction indicated. In this example, the drive voltage is applied first by electrical contact 108. As the second magnet 606 moves in the indicated direction, the interaction of the magnetic fields of magnets 604, 606 causes magnet 604 to be driven in an opposite direction as indicated in FIG. 7. As first magnet 604 is driven under the influence of the magnets' magnetic fields, user engageable portion 202 is moved in a first direction, as shown in FIG. 7. A second drive voltage is then applied by electrical contact 110 to cause second magnet 606 to be moved in the opposite direction as shown in FIG. 8. Again, this causes the magnetic fields of the magnet assembly to interact with one another and move the key or keyboard element back to what can be considered a starting location or equilibrium point.
Drive Circuit
FIG. 8a illustrates an example drive circuit in accordance with one embodiment, generally at 800. Here, there is a high side stack 802 and a low side stack 804. A supply voltage is connected across the stacks to ground. A phaseout node 806 is provided between the high side stack 802 and the low side stack 804.
Individual stacks are defined by collections of series-connected field effect transistors (FETs) individual ones of which are connected in parallel with a capacitive element or capacitor as shown. The parallel-connected capacitors reduce static power consumption. During a switching transient, the parallel capacitors equally share the voltage drop across the stack so that the sharing is even at the end of the dynamic mode.
Since there is no static current draw, there is no charge depletion to offset the balance. Of course there is always leakage in the capacitors and capacitive actuator that would be considered static current draw, but the FETs themselves have enough drain-source leakage that the leakage of the capacitors and load are offset and the system remains stable with a fast response. The leakage of the FETs is enough to maintain the static voltage sharing but since it is on the order of nanoamps there is an acceptable level of power dissipation, even for many stacks of devices in parallel.
As a design consideration, when driving capacitive loads, the dynamic load balancing is affected by the load charging time constant, causing the FET nearest the output to carry too little voltage which can make the other FETS fail due to exceeding their drain-source voltage rating when operating at high voltages close to the maximum rating of the stack. This happens as the stack turns on because the charge of capacitive load is lagging and therefore drawing as much charge from the neighboring nodes as possible. This charge depletion offsets the balance across the FETs since the resistance of the switching devices limits the current flow to the output. However, adding a capacitor across the nearest FET to the output (on the order of 1:50 actuator to added capacitor) solves the problem for these devices and switch speed since the capacitors will not let voltages change as quickly. When combining this corrective factor and the already existing parallel capacitors, all the capacitors in parallel with the FETs are the same value in order to keep the voltage sharing equal across the devices.
Detent Structure
In at least some embodiments, a detent structure can be utilized to impart a snapover effect when the user depresses a key or keyboard element. Any suitable detent structure can be utilized. As an example, consider FIG. 9.
There, a key or keyboard element is shown generally at 900. A frame 902 supports electrically-deformable material 904. A detent structure 906 includes a knob 908 which is supported by a flange 910 which acts as a spring. User-engageable portion 912 includes a pair of concave indentations 914. In this example, when the electrically-deformable material is driven by a voltage, it moves detent structure 906 causing knob 908 to ride into and out of the concave indentations 914 underneath the user engageable portion 912. As engagement and disengagement occurs between knob 908 and the concave indentations 914, a change in velocity takes place which is translated to the top surface of user engageable portion 912. This, in turn, provides haptic tactile feedback to a user's finger.
Example System
FIG. 10 illustrates an example system in accordance with one embodiment generally at 1000. System 1000 includes, in this example, a computing device 1002 and a keyboard unit 1004. Computing device 1002 can include any suitable computing device such as a desktop computing device, laptop computer, notebook computer and the like.
Keyboard unit 1004 includes, in this example, a host input/output module 1006 which enables communication between computing device 1002 and keyboard unit 1004. Any suitable module can be used examples of which include, by way of example and not limitation, Universal Serial Bus (USB) modules, Bluetooth modules, RS232, PS2, CAN, TCPIP, and the like. Keyboard unit 1004 further includes a microprocessor 1008, a switch interface 1010, a switch 1012, an actuator interface 1014, an actuator 1016, and, optionally, an audio interface 1018 and an audio output device 1020. These various components can be implemented in connection with any suitable hardware, software, firmware or combination thereof. In at least some embodiments, components of the keyboard unit can be implemented as an application specific integrated circuit or ASIC.
In operation, switch 1012 is configured to sense when a particular key or keyboard element is depressed. One example of such a switch is switch closure elements 204, 206 in FIG. 2. Of course, other switch arrangements can be utilized without departing from the spirit and scope of the claimed subject matter, examples of which are provided above. Switch interface 1010 notifies microprocessor 1008 when a depression event has occurred. Microprocessor 1008 controls actuator interface 1014, which can include the above-mentioned drive electronics, effective to cause the drive electronics to apply a drive voltage(s) to actuator 1016. Actuator interface 1014 can be implemented in connection with any suitable hardware, software, firmware, or combination thereof. In this example, actuator 1016 includes both the electrically-deformable material, as well as the physical structure that is mounted to a key or keyboard element.
As noted above, the drive electronics can be used to drive the electrically-deformable material in any suitable way to achieve any suitable movement. In at least some embodiments, the drive electronics are utilized to drive the electrically-deformable material in a manner that imparts multi-vectored movement to the material and hence, to the key or keyboard element with which it is associated. In a specific implementation, this multi-vectored movement comprises a first movement in a first direction, and then a second movement in a second different direction. Of course, other movements and various other directions can be used without departing from the spirit and scope of the claimed subject matter.
Optionally, keyboard unit 1004 can include an audio interface 1018 and an associated audio output device 1020. In at least some embodiments, audio interface 1018 is in communication with microprocessor 1008 and can be configured to produce sounds associated with key or keyboard element depression events. For example, in at least some embodiments, sound recordings of key depressions can be saved and used by the audio interface 1018 to produce, via audio output device 1020, a key depression sound when the key is depressed by the user.
Logical Key Groupings
In at least some embodiments, multiple keys or keyboard elements can be grouped together into a logical grouping which is driven in a multi-vectored manner to provide haptic feedback to a user. In this instance, each logical grouping constitutes a plate which is moved under the influence of the electrically-deformable material. In at least some embodiments, a keyboard can have single keys or keyboard elements that are driven under the influence of the electrically-deformable material, as well as logical groupings of keys or keyboard elements that are driven under the influence of the electrically-deformable material.
As an example, consider FIG. 11. There, an example keyboard, in accordance with one or more embodiments, is shown generally at 1100. In this example, a keyboard housing 1101 contains or otherwise supports a plurality of keys. Some of the individual keys are grouped into two logical groupings 1102, 1104. These logical groupings define plates that are each moved in a multi-vectored manner as described above. In addition, a plate 1106 includes the space bar key and is separately driven by its own actuator. For clarity, the individual logical groupings are represented both superimposed on the illustrated keyboard and separately underneath the keyboard. It is to be appreciated and understood that in at least some embodiments, when individual keys or key groupings are moved, the overall housing that supports the keys is not moved. Effectively then, the systems described above can, in at least some embodiments, provide for discrete individual movement of keys or key groupings without moving the corresponding housing.
It is to be appreciated and understood that any suitable grouping of keys or keyboard elements can be used. In this particular example, the logical grouping of keys corresponds to those keys that are typically used by the right hand, and those keys that are typically used by the left hand. Of course, other logical key groupings can be used without departing from the spirit and scope of the claimed subject matter.
Example Method
FIG. 12 is a flow diagram that describes steps a method in accordance with one embodiment. The method can be implemented in connection with any suitable hardware, software, firmware or combination thereof. In at least some embodiments, the method can be implemented by a system, such as those systems shown and described above. It is to be appreciated and understood that the described method can be implemented by systems other than those described above without departing from the spirit and scope of the claimed subject matter.
Step 1200 presses a key or keyboard element. This step is typically performed by a user. Step 1202 detects an associated switch closure. In the illustrated and described embodiments, a switch associated with a depressed key is utilized to ascertain when the key has been depressed. One specific example of how this can be done is provided above. Of course, other ways of sensing or detecting a switch closure can be used without departing from the spirit and scope of the claimed subject matter.
Responsive to detecting a switch closure at 1202, step 1204 activates a first drive line for the associated key or key board element. In one or more embodiments, the drive line is connected to an electrically-deformable material as described above. Activating the first drive line causes the electrically-deformable material to deform and hence, move the associated key in a first direction. Step 1206 activates a second drive line for the associated key or keyboard element. Again, this drive line is connected to the electrically-deformable material as described above. Activating the second drive line causes the electrically-deformable material to deform and hence, move the associated key in a second different direction. In the example above, the first and second directions are generally opposite of one another. In addition, the direction of movement is generally orthogonal to the direction of force applied by the user to depress the key. In this manner, the electrically-deformable material can be electrically driven to impart a multi-vectored movement to the key or keyboard element. As pointed out above, however, other directions of movements can be used without departing from the spirit and scope of the claimed subject matter. For example, a particular key may be driven in three or more directions to impart a desired haptic response.
Various embodiments can enable keyboards to provide a desired haptic response, yet be designed to embody a smaller form factor than those typically designed using rubber dome technology. In accordance with one or more embodiments, form factors of the switch, EAP and keytop can be designed as follows. It is to be appreciated and understood that the described form factors constitutes examples of one embodiment. As such, other form factors can be used without departing from the spirit and scope of the claimed subject matter. The described form factors refer to the vertical thickness of the identified elements, for example, as viewed in FIG. 2.















Range (between
Implementation



Upper (about)
about)
(about)







Switch
 .50 mm
.0508 mm-.50 mm 
.2286 mm 


EAP
2.00 mm
.0175 mm-2.00 mm
1.00 mm


Keytop
1.50 mm
 .254 mm-1.50 mm
.508 mm


Totals
4.00 mm
.3223 mm-4.00 mm
1.7366 mm 









Reduced Work Keys or Keyboard Elements
As noted above, actuation force, travel distance, and tactile snapover effect are three primary keyboard attributes. Actuation force and travel distance correspond with one another and serve to define an amount of user work associated with effectuating switch closure of a key or keyboard element. Tactile snapover effect is associated with haptic feedback which users typically associate with a valid switch closure.
With current technologies, achieving an acceptable tactile snapover effect typically requires a significant actuation force and travel distance, and thus a significant amount of user work. This is primarily due to the physical constraints of actuating mechanisms used in these technologies. More particularly, and as explained above, these technologies typically employ an elastomeric dome, e.g., rubber dome, actuating mechanism in which tactile snapover is achieved by the collapse of the elastomeric dome. Naturally, a sufficient actuation force must be exerted on a key or keyboard element to cause sufficient downward vertical travel until the dome collapses and switch closure is achieved. Attempts to lower the necessary actuation force and/or travel distance for keys or keyboard elements implemented according to these current technologies have resulted in a loss of tactile response or haptic feedback.
With keys or keyboard elements implemented according to one or more of the described embodiments, mechanical elastomeric dome actuating mechanisms can be avoided by utilizing an electrically-deformable material, e.g., an EAP, as an actuating mechanism. By employing an electrical actuating mechanism rather than a mechanical actuating mechanism, a thinner key or keyboard element assembly having a more planar, multi-vectored movement is possible. As explained above, this multi-vectored movement produces a perceived acceleration of the key or keyboard element, and thus provides a user with a tactile snapover effect. A tactile snapover effect can thus be provided without requiring the actuation force and travel distance necessary to collapse a mechanical dome to effect switch closure. Instead, an actuation force and travel distance can be chosen based on enhancing the user's interaction with the key or keyboard element.
As a result, the amount of work to actuate a key or keyboard element can be significantly decreased or even eliminated. This is perhaps best shown in FIG. 13 which includes two example force displacement curves 1302 and 1306. Example force displacement curve 1302 is illustrative of a typical key or keyboard element employing a traditional mechanical elastomeric dome actuating mechanism. Note that by virtue of requiring a dome to be collapsed to effect switch closure, a significant amount of actuation force and travel distance is necessary. Accordingly, a relatively large amount of work is required, shown here as the area under the curve designated work 1304. Example force displacement curve 1306, in contrast, is illustrative of an example key or keyboard element implemented according to one or more of the described embodiments. In this example, an actuation force of approximately 60 grams and a travel distance less than 0.25 millimeters have been chosen. As shown, this actuation force and travel distance are associated with significantly less user work, shown here as the area under the curve designated work 1308.
As an example of a key or keyboard element implemented according to one or more of the described embodiments, consider FIG. 14. There, key or keyboard element 100 is illustrated with like numerals from FIGS. 1 and 2 depicting like components. Key or keyboard element 100 is associated with an underlying surface 1402. Key or keyboard element 100 can be associated with underlying surface 1402 in any suitable way. For example, underlying surface 1402 can be part of key or keyboard element 100. Alternatively or additionally, underlying surface 1402 can be part of another structure, such as a keyboard housing which contains or otherwise supports key or keyboard element 100. Underlying surface 1402 can be any suitable type of surface, such as a printed silicon circuit for example.
As illustrated and described above, when a user depresses or otherwise interacts with key or keyboard element 100, switch closure elements 204, 206 are brought into communication, thus closing the switch formed by these elements and allowing circuitry described above to detect the interaction and cause one or more drive voltages to be applied to electrically-deformable material 104. As a result, a multi-vectored movement is imparted to actuator 106, and thus portion 202, to provide a tactile snapover effect to the user. As explained above, by virtue of employing an electrical actuating mechanism, the tactile snapover effect can be achieved with comparatively little or no actuation force and/or travel distance. Accordingly, in this example, key or keyboard element 100 is associated with an actuation force parameter range 1404 of between 0 grams to about 80 grams and a travel distance range 1406 of between 0 millimeters to about 2.5 millimeters. One or both of these ranges, or any parameter(s) and/or sub-range(s) of parameters within these ranges, can be chosen to enhance the tactile response based on the particular scenario at hand.
For example, consider a scenario involving a keyboard where an actuation force and/or key or keyboard element travel is not desirable. In such a scenario, a suitable sensor might be utilized to detect or sense the proximity of an object, e.g., a user's finger, within a certain distance of key or keyboard element 100. By way of example and not limitation, a suitable sensor might include a capacitive sensor, projected field sensor, surface acoustic wave sensor, infrared sensor, image sensing sensor, and/or force sensing sensor. Furthermore, the switch formed by switch closure elements 204, 206 can be configured such that it closes in response to the object being detected, thus causing key or keyboard element 100 to be actuated. Accordingly, actuation of key or keyboard element 100 can be achieved without requiring an actuation force and/or travel distance.
Consider another example scenario where an actuation force of between about 40 grams to 60 grams and/or a travel distance of between 0 millimeters to about 1.5 millimeters are desired. The switch formed by switch closure elements 204, 206 can be configured such that it closes in response to a force within this actuation force parameter sub-range and/or to travel within this travel distance parameter sub-range, thus causing key or keyboard element 100 to be actuated.
Consider yet another example scenario where an actuation force of about 60 grams and/or travel distance of about 1.5 millimeters are desired. The switch formed by switch closure elements 204, 206 can be configured such that switch closure is achieved in response to a force of about 60 grams and/or to travel of about 1.5 millimeters.
Example Reduced Work Method
FIG. 15 is a flow diagram that describes steps in a method in accordance with one embodiment. The method can be implemented in connection with any suitable hardware, software, firmware or combination thereof. In at least some embodiments, the method can be implemented by a system, such as those systems shown and described above. It is to be appreciated and understood, however, that the described method can be implemented by systems other than those described above without departing from the spirit and scope of the claimed subject matter.
Step 1500 interacts with a key or keyboard element. This step is typically performed by a user and, as noted above, can be associated with comparatively little or no actuation force and/or travel distance. For example, the user may depress the key or keyboard element such that between 0 grams to about 80 grams of force and/or between 0 millimeters to about 2.5 millimeters of travel distance are imparted to the key or keyboard element. As another example, the user may place their finger within a certain distance of the key or keyboard element such that it can be sensed as being proximate to the key or keyboard element—without requiring the user to impart a measurable force and/or travel distance to the key or keyboard element.
Responsive to the interaction at step 1500, step 1502 effectuates switch closure. As described above, in at least some embodiments, this can be accomplished by bringing a suitable switch arrangement into communication, allowing circuitry to detect the interaction. Alternatively or additionally, in at least some embodiments, a sensor might be utilized to help detect or sense the interaction.
In an event of a switch closure at step 1502, step 1504 actuates the key or keyboard element. As illustrated and described above, this can be accomplished by utilizing an electrical actuating mechanism to impart a multi-vectored movement to the key or keyboard element to provide the user with a tactile snapover effect.
CONCLUSION
Various embodiments provide keyboards that utilize an electrically-deformable material as an actuating mechanism to provide haptic feedback to a user of the keyboard. In at least some embodiments, the electrically-deformable material is utilized to impart, to a depressed key or keyboard element, a multi-vectored movement that produces a perceived acceleration of the key or keyboard element thus providing a user with haptic feedback which simulates a snapover movement.
In at least some embodiments, the electrically-deformable material is driven with a voltage responsive to a user depressing a key or keyboard element. In these embodiments, switch closure is first attained followed by the haptic feedback provided through the multi-vectored movement of the key or keyboard element. In at least some embodiments, the multi-vectored movement moves the key or keyboard element in at least a first direction, and then a second direction which is different from the first. Each of the directional movements is induced by its own driven voltage which is applied to different areas of the electrically-deformable material. In at least some embodiments, one of the directions of movement moves the key or keyboard element a distance which is greater than another of the directions of movement.
In a specific embodiment, a first direction of movement is generally toward the user and a second direction of movement is generally away from the user. In at least some embodiments, the first direction moves the key or keyboard element a distance which is less than a distance that the second direction moves the key or keyboard element. In one embodiment, the first direction moves the key or keyboard element a distance which is about half the distance that the second direction moves the key or keyboard element.
In at least some embodiments, multiple keys or keyboard elements can be grouped together into a logical grouping which is driven in a multi-vectored movement to provide haptic feedback. In this instance, each logical grouping constitutes a plate which is moved under the influence of the electrically-deformable material. In at least some embodiments, a keyboard can have single keys or keyboard elements that are driven under the influence of the electrically-deformable material, as well as logical groupings of keys or keyboard elements that are driven under the influence of the electrically-deformable material.
In at least some embodiments, the electrically-deformable material comprises an electroactive polymer or EAP. Other electrically-deformable materials can, of course, be used.
In at least some embodiments, a key or keyboard element can be associated with comparatively little or no actuation force and/or travel distance. As a result, the amount of work necessary to actuate the key or keyboard element can be significantly decreased or eliminated. In these embodiments, switch closure can be effectuated in response to a force applied to the key or keyboard element of about 80 grams or less and/or a travel distance of the key or keyboard of about 2.5 millimeters or less. The key or keyboard element can then be actuated upon switch closure by providing a multi-vectored movement to the key or keyboard element to achieve a tactile snapover effect.
In at least some embodiments, switch closure of a key or keyboard element can be effectuated in response to detecting an interaction. The interaction can be associated with a force applied to the key or keyboard element of about 80 grams or less and/or a travel distance of the key or keyboard of about 2.5 millimeters or less. For example, a user might depress the key or keyboard element, or simply place their finger proximate to it. The key or keyboard element can then be actuated upon switch closure.
Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

## Claims

1. A keyboard comprising:
a plurality of keys or keyboard elements grouped into plural logical groupings, wherein each logical grouping can be separately driven in a multi-vectored movement to provide a haptic feedback;
a keyboard housing, wherein the keyboard housing supports the plurality of keys or keyboard elements;
a switch associated with a key or keyboard element; and
an actuating mechanism operably associated with the switch and the key or keyboard element for providing the haptic feedback to each of the logical groupings, wherein the actuating mechanism is configured to actuate the key or keyboard element in an event of a switch closure.

2. The keyboard of claim 1, wherein each logical grouping includes a plate.

3. The keyboard of claim 2, wherein the plate is moved under the influence of an electrically-deformable material.

4. The keyboard of claim 1, wherein a single key or keyboard element is moved under the influence of the electrically-deformable material.

5. The keyboard of claim 1, wherein the keyboard housing does not move when the single key or keyboard element is moved under the influence of the electrically-deformable material.

6. The keyboard of claim 1, wherein the logical grouping of keys or keyboard elements is moved under the influence of the electrically-deformable material.

7. The keyboard of claim 1, wherein the keyboard housing does not move when the logical grouping of keys or keyboard elements is moved under the influence of the electrically-deformable material.

8. The keyboard of claim 1, wherein the multi-vectored movement is caused by the electrically-deformable material.