The present invention is directed to the use of electroactive polymer transducers to provide an improved haptic response.
A tremendous variety of devices used today rely on actuators of one sort or another to convert electrical energy to mechanical energy. Conversely, many power generation applications operate by converting mechanical action into electrical energy. Employed to harvest mechanical energy in this fashion, the same type of device may be referred to as a generator. Likewise, when the structure is employed to convert physical stimulus such as vibration or pressure into an electrical signal for measurement purposes, it may be characterized as a sensor. Yet, the term “transducer” may be used to generically refer to any of the devices.
A number of design considerations favor the selection and use of advanced dielectric elastomer materials, also referred to as “electroactive polymers” (EAPs), for the fabrication of transducers. These considerations include potential force, power density, power conversion/consumption, size, weight, cost, response time, duty cycle, service requirements, environmental impact, etc. As such, in many applications, EAP technology offers an ideal replacement for piezoelectric, shape-memory alloy (SMA) and electromagnetic devices such as motors and solenoids.
Examples of EAP devices and their applications are described in U.S. Pat. Nos. 7,394,282; 7,378,783; 7,368,862; 7,362,032; 7,320,457; 7,259,503; 7,233,097; 7,224,106; 7,211,937; 7,199,501; 7,166,953; 7,064,472; 7,062,055; 7,052,594; 7,049,732; 7,034,432; 6,940,221; 6,911,764; 6,891,317; 6,882,086; 6,876,135; 6,812,624; 6,809,462; 6,806,621; 6,781,284; 6,768,246; 6,707,236; 6,664,718; 6,628,040; 6,586,859; 6,583,533; 6,545,384; 6,543,110; 6,376,971 and 6,343,129; and in U.S. Published Patent Application Nos. 2009/0001855; 2009/0154053; 2008/0180875; 2008/0157631; 2008/0116764; 2008/0022517; 2007/0230222; 2007/0200468; 2007/0200467; 2007/0200466; 2007/0200457; 2007/0200454; 2007/0200453; 2007/0170822; 2006/0238079; 2006/0208610; 2006/0208609; and 2005/0157893, and U.S. patent application Ser. No. 12/358,142 filed on Jan. 22, 2009; PCT application No. PCT/US09/63307; and WO 2009/067708, the entireties of which arc incorporated herein by reference.
An EAP transducer comprises two electrodes having deformable characteristics and separated by a thin elastomeric dielectric material. When a voltage difference is applied to the electrodes, the oppositely charged electrodes attract each other thereby compressing the polymer dielectric layer therebetween. As the electrodes are pulled closer together, the dielectric polymer film becomes thinner (the z-axis component contracts) as it expands in the planar directions (along the x- and y-axes), i.e., the displacement of the film is in-plane. The EAP film may also be configured to produce movement in a direction orthogonal to the film structure (along the z-axis), i.e., the displacement of the film is out-of-plane. U.S. Published Patent Application No. 2005/0157893 discloses EAP film constructs which provide such out-of-plane displacement—also referred to as surface deformation or as thickness mode deflection.
The material and physical properties of the EAP film may be varied and controlled to customize the deformation undergone by the transducer. More specifically, factors such as the relative elasticity between the polymer film and the electrode material, the relative thickness between the polymer film and electrode material and/or the varying thickness of the polymer film and/or electrode material, the physical pattern of the polymer film and/or electrode material (to provide localized active and inactive areas), the tension or pre-strain placed on the EAP film as a whole, and the amount of voltage applied to or capacitance induced upon the film may be controlled and varied to customize the features of the film when in an active mode.
Numerous transducer-based applications exist which would benefit from the advantages provided by such EAP films. One such application includes the use of EAP films to produce haptic feedback (the communication of information to a user through forces applied to the user's body) in user interface devices. There are many known user interface devices that employ haptic feedback, typically in response to a force initiated by the user. Examples of user interface devices that may employ haptic feedback include keyboards, keypads, game controller, remote control, touch screens, computer mice, trackballs, stylus sticks, joysticks, etc. The user interface surface can comprise any surface that a user manipulates, engages, and/or observes regarding feedback or information from the device. Examples of such interface surfaces include, but are not limited to, a key (e.g., keys on a keyboard), a game pad or buttons, a display screen, etc.
The haptic feedback provided by these types of interface devices is in the form of physical sensations, such as vibrations, pulses, spring forces, etc., which a user senses either directly (e.g., via touching of the screen), indirectly (e.g., via a vibrational effect such a when a cell phone vibrates in a purse or hag) or otherwise sensed (e.g., via an action of a moving body that creates a pressure disturbance but does not generate an audio signal in the traditional sense).
Moreover, the proliferation of electronic media devices such as smart phones, personal media players, portable computing devices, portable gaming systems, electronic readers, etc., can create a situation where a sub-segment of customers would benefit or desire an improved haptic effect in the electronic media device. However, increasing haptic capabilities in every model of an electronic media device may not be justified due to increased cost or increased profile of the device. Moreover, customers of certain electronic media devices may desire to temporarily improve the haptic capabilities of the electronic media device for certain activities.
Haptic feedback capabilities are known to improve user productivity and efficiency, particularly in the context of data entry. The present inventors believe that further improvements to the character and quality of the haptic sensation communicated to a user may further increase such productivity and efficiency. It would be additionally beneficial if such improvements were provided by a sensory feedback mechanism which is easy and cost-effective to manufacture, and does not add to, and preferably reduces, the space, size and/or mass requirements of known haptic feedback devices.
While the incorporation of EAP based transducers can improve the haptic interaction on such user interface devices, there remains a need to temporarily employ such EAP transducers without increasing the profile of the actual electronic media device. Furthermore, there also remains a need to either temporarily or permanently improve the haptic capability of a fully functional stand alone electronic media device so that the user can decide whether or not to improve haptic capabilities of the stand alone electronic media device.
The present invention includes devices, systems and methods involving electroactive polymer transducers for haptic or sensory applications. In one variation, the device includes a housing assembly capable of being removable coupled with an electronic media device. The electronic media device can deliver an output signal to an output port, where the housing assembly produces a haptic effect in response to the output signal of the electronic media device. Alternate variations of the devices and methods disclosed herein can use transducers or actuators in place of or in combination with electroactive polymers. Such transducers or actuators can comprise piezoelectric transducers, vibratory motors, etc.
One benefit of the devices and method described herein includes the ability to retrofit or customize an electronic media device to provide the user with improved haptic feedback whenever an input is triggered by software or another signal generated by the device or associated components.
The electroactive polymer artificial muscle (“EPAM”) transducers that can be used with these designs include, but are not limited to Planar, Diaphragm, Thickness Mode, and Passive Coupled devices (Hybrids) as well as any type of EPAM device described in the commonly assigned patents and applications cited herein.
One variation of a housing assembly for removably coupling with an electronic media device comprises a housing case adapted to nest at least a portion of electronic media device, the housing including at least one media device connector adapted to detachably couple to the output port of the electronic media device; at least one electroactive polymer actuator having an active portion configured to produce movement in response to a triggering signal; a body mass located within the housing case and coupled to the electroactive polymer actuator, where haptic effect of the electroactive polymer actuator comprises an inertial movement of the body mass; and at least one drive electronics assembly configured to electronically couple the electroactive polymer actuator to the media device connector, such that the drive electronics assembly is capable of generating the triggering signal in response to the output signal of the electronic media device. Variations of such devices can include any type of transducer including non-electroactive polymer transducers.
In many cases, the electronic media device comprises a stand-alone device that remains operable upon detaching from the housing assembly. However, variations include using a media device that is not operable unless coupled to the housing assembly. Additional variations of the housing assemblies include assemblies that do not have a separate battery or power supply. Instead, the electroactive polymer actuator can be powered by an external source or by the media device. In some variations, the electroactive polymer actuator comprises at least one electroactive polymer cartridge, where the electroactive polymer cartridge includes an electroactive polymer film comprising a dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is between a first and a second electrodes wherein the overlapping portions of the electrodes define an active area comprising the active portion, whereupon application of a triggering signal to the electrodes causes movement of the active area to produce the haptic effect.
The electroactive polymer actuator can include a plurality of discrete electroactive polymer cartridges coupled together, where the electroactive polymer actuator includes an increased active portion comprising each active area of each electroactive polymer cartridge.
In some variations, a body mass can be located within the housing case and coupled to the electroactive polymer actuator, where the haptic effect of the electroactive polymer actuator comprises an inertial movement of the body mass that is driven by the electroactive polymer actuator. While the body mass could be a separate inertial mass it could also comprise a battery, an electronics circuit board or other functional component. In alternate variations, the electroactive actuator is coupled to the media device, such that the haptic effect is discernable on the media device.
In some cases, the housing comprises a pocket located within an interior of the housing case, where the body mass is located within the pocket. The pocket can be sized to limit movement of the body mass to limit movement of the electroactive polymer actuator. By limiting movement of the electroactive polymer actuator, the pocket reduces the chance that the electroactive polymer will be damaged through over-extension.
The power supply can be used as the inertial mass and can be coupled to the electroactive polymer actuator such that movement of the active area causes inertial movement of the power supply to produce the haptic effect.
The housing assembly can optionally include at least one audio speaker, where the electronic drive assembly is configured to pass the output signal of the electronic media device through to the audio speaker.
The housing assembly can comprise any number of parts. In those cases where the assembly case comprises more than one piece, the pieces can be configured to be removably coupled together to nest the electronic media assembly.
The invention also includes a method of augmenting an electronic media device to produce an improved haptic effect. In one variation, the method includes providing a housing including at least one media device connector adapted to couple to an output port of the electronic media device, the housing further includes at least one electroactive polymer actuator having an active portion; coupling the output port of the electronic media device to device connector; producing a triggering signal in response to an output signal of the electronic media device; and generating the improved haptic effect by transmitting the triggering signal to the electroactive polymer actuator to cause movement of the active portion.
In certain variations, the method includes generating the improved haptic effect by transmitting the triggering signal to the electroactive polymer actuator to cause movement of the active portion causes inertial movement of a body mass within the housing case. Optionally, the body mass can comprise a portion of the housing assembly such as the power supply or other components.
In another variation, the method includes powering the electroactive polymer actuator using the power supply, which is electrically isolated from the electronic media device.
Another variation of the method includes producing the triggering signal in response to the output signal of the electronic media device by transmitting the output signal to at least one external speaker coupled to the housing case.
The methods described herein can include assessing the output signal and selecting an output mode of the electroactive actuator from a plurality of output modes depending on the output signal.
The invention described herein further includes a method of producing a housing assembly to augment a haptic effect of an electronic media device when coupled thereto. For example, the method can include positioning at least one electroactive polymer actuator having an active portion within a housing structure including at least one media device connector that allows for detachable joining of the electronic media device to the housing structure; coupling an inertial mass to the active portion, such that movement of the active portion creates the haptic effect by inertial movement of the inertial mass, where the haptic effect is felt in the housing assembly or electronic media device when coupled thereto; and providing within the housing electronic drive circuitry to electrically couple the media device connector to the electroactive polymer actuator and to generate a trigger signal upon receipt of an output signal from the electronic media device, where the electronic drive circuitry is configured to transmit the trigger signal to the electroactive polymer actuator to cause movement of the active portion.
The method of producing a housing assembly to augment a haptic effect of an electronic media device when coupled thereto can further include increasing a total surface area of the active portion by coupling a plurality of electroactive polymer cartridges, each having an electroactive polymer film comprising a dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is between a first and a second electrodes wherein the overlapping portions of the electrodes define an active area; where the active portion comprises a total area of the plurality of active areas.
In another variation, the method can include configuring the electronic drive circuitry to assess the output signal and select an output mode of the electroactive actuator from a plurality of output modes depending on the output signal.
As for other details of the present invention, materials and alternate related configurations may he employed as within the level of those with skill in the relevant art. The same may hold true with respect to method-based aspects of the invention in terms of additional acts as commonly or logically employed. In addition, though the invention has been described in reference to several examples, optionally incorporating various features, the invention is not to be limited to that which is described or indicated as contemplated with respect to each variation of the invention. Various changes may be made to the invention described and equivalents (whether recited herein or not included for the sake of some brevity) may be substituted without departing from the true spirit and scope of the invention. Any number of the individual parts or subassemblies shown may be integrated in their design. Such changes or others may be undertaken or guided by the principles of design for assembly.
These and other features, objects and advantages of the invention will become apparent to those persons skilled in the art upon reading the details of the invention as more fully described below. In addition, variations of the methods and devices described herein include combinations of the embodiments or of aspects of the embodiments where possible are within the scope of this disclosure even if those combinations are not explicitly shown or discussed.
The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings. To facilitate understanding, the same reference numerals have been used (where practical) to designate similar elements that are common to the drawings. Included in the drawings are the following:
The devices, systems and methods of the present invention are now described in detail with reference to the accompanying figures.
It is noted that the figures discussed herein schematically illustrate exemplary configurations of devices that employ electroactive polymer (“EAP”) films or transducers having such EAP films. Many variations arc within the scope of this disclosure, for example, in variations of the device, the EAP transducers can be implemented to move a mass to produce an inertial haptic sensation. Alternatively, the EAP transducer can produce movement in the electronic media device when coupled to the assembly described herein.
In any application, the feedback displacement created by the EAP transducer can be exclusively in-plane which is sensed as lateral movement, or can be out-of-plane (which is sensed as vertical displacement). Alternatively, the EAP transducer material may be segmented to provide independently addressable/movable sections so as to provide angular displacement of the housing or electronic media device or combinations of other types of displacement. In addition, any number of EAP transducers or films (as disclosed in the applications and patent listed herein) can be incorporated in the user interface devices described herein.
The EAP transducer may be configured to displace to an applied voltage, which facilitates programming of a control system used with the subject tactile feedback devices. EAP transducers are ideal for such applications for a number of reasons. For example, because of their light weight and minimal components, EAP transducers offer a very low profile and, as such, are ideal for use in sensory/haptic feedback applications.
As seen in
With a voltage applied, the transducer film 10 continues to deflect until mechanical forces balance the electrostatic forces driving the deflection. The mechanical forces include elastic restoring forces of the dielectric layer 12, the compliance or stretching of the electrodes 14, 16 and any external resistance provided by a device and/or load coupled to transducer 10. The resultant deflection of the transducer 10 as a result of the applied voltage may also depend on a number of other factors such as the dielectric constant of the elastomeric material and its size and stiffness. Removal of the voltage difference and the induced charge causes the reverse effects.
In some cases, the electrodes 14 and 16 may cover a limited portion of dielectric film 12 relative to the total area of the film. This may be done to prevent electrical breakdown around the edge of the dielectric or achieve customized deflections in certain portions thereof. Dielectric material outside an active area (the latter being a portion of the dielectric material having sufficient electrostatic force to enable deflection of that portion) may be caused to act as an external spring force on the active area during deflection. More specifically, material outside the active area may resist or enhance active area deflection by its contraction or expansion.
The dielectric film 12 may be pre-strained. The pre-strain improves conversion between electrical and mechanical energy, i.e., the pre-strain allows the dielectric film 12 to deflect more and provide greater mechanical work. Pre-strain of a film may be described as the change in dimension in a direction after pre-straining relative to the dimension in that direction before pre-straining. The pre-strain may comprise elastic deformation of the dielectric film and be formed, for example, by stretching the film in tension and fixing one or more of the edges while stretched. The pre-strain may be imposed at the boundaries of the film or for only a portion of the film and may be implemented by using a rigid frame or by stiffening a portion of the film.
The transducer structure of
In fabricating a transducer, an elastic film 26 can be stretched and held in a pre-strained condition by a rigid frame 8. In those variations employing a 4-sided frame, the film can be stretched bi-axially. It has been observed that the pre-strain improves the dielectric strength of the polymer layer 26, thereby improving conversion between electrical and mechanical energy, i.e., the pre-strain allows the film to deflect more and provide greater mechanical work. Typically, the electrode material is applied after pre-straining the polymer layer, but may be applied beforehand. The two electrodes provided on the same side of layer 26, referred to herein as same-side electrode pairs, i.e., electrodes on the top side of dielectric layer 26 and electrodes on a bottom side of dielectric layer 26, can be electrically isolated from each other. The opposed electrodes on the opposite sides of the polymer layer form two sets of working electrode pairs, i.e., electrodes spaced by the EAP film 26 form one working electrode pair and electrodes surrounding the adjacent exposed EAP film 26 form another working electrode pair. Each same-side electrode pair can have the same polarity, while the polarity of the electrodes of each working electrode pair are opposite each other. Each electrode has an electrical contact portion configured for electrical connection to a voltage source.
In this variation, the electrodes 32 are connected to a voltage source via a flex connector 30 having leads 22, 24 that can be connected to the opposing poles of the voltage source. The cartridge 12 also includes conductive vias 18, 20. The conductive vias 18, 20 can provide a means to electrically couple the electrodes 8 with a respective lead 22 or 24 depending upon the polarity of the electrodes.
The cartridge 12 illustrated in
An electroactive polymer actuator for use in the methods and devices described herein can then be formed in a number of different ways. For example, the electroactive polymer can be formed by stacking a number of cartridges 12 together, having a single cartridge with multiple layers, or having multiple cartridges with multiple layers. Typically, manufacturing and yield considerations favor stacking single cartridges together to form the electroactive polymer actuator. In doing so, electrical connectivity between cartridges can be maintained by electrically coupling the vias 18, 20 together so that adjacent cartridges are coupled to the same voltage source or power supply.
The cartridge 12 shown in
Depending upon the electrode configurations, the electroactive actuators 14 can be capable of functioning in either a single or a dual-phase mode (also known as a two-phase mode). When operating as a single mode actuator only one set of working pairs of electrodes of actuator 14 would be activated at any one time. In a configuration that includes multiple areas of active electrodes (like those shown in
By connecting the mechanically coupled portions 90, 92 of the actuator electrically in series and controlling their common node 155, such as in the manner illustrated in the block diagram 140 of
In the illustrated variation, the housing assembly 100 includes a housing or case 102 adapted to nest at least a portion of electronic media device (200 as shown in
The housing case 102 can comprise a flexible or textured sleeve to provide improved handing grip and ruggedness to the media device. Alternatively, the housing case 102 can comprise a rigid material to provide added protection to the device. The media device 200 nests within a pocket or cavity 106. To accommodate placement, the media device connector 104 can swivel or articulate to allow for ease of coupling the media device 200 to the case 102.
The methods and devices described herein can generate the haptic effect by a sound signal provided by the media device. Such a configuration eliminates the need for a separate processor to generate waveforms to produce different types of haptic sensations. Instead, haptic devices can employ one or more circuits to modify an existing audio signal into a modified haptic signal, e.g. filtering or amplifying different portions of the frequency spectrum. Therefore, the modified haptic signal then drives the actuator. In one example, the modified haptic signal drives the power supply to trigger the actuator to achieve different sensory effects. This approach has the advantages of being automatically correlated with and synchronized to any audio signal which can reinforce the feedback from the music or sound effects in a haptic device such as a gaming controller or handheld gaming console.
In another example, the circuit can include one or more rectifiers to filter the frequency of an audio signal to use all or a portion of an audio waveform of the audio signal to drive the haptic effect.
In another implementation, a threshold in the audio signal can be used to trigger the operation of a secondary circuit which drives the actuator. The threshold can be defined by the amplitude, the frequency, or a particular pattern in the audio signal. The secondary circuit can have a fixed response such as an oscillator circuit set to output a particular frequency or can have multiple responses based on multiple defined triggers. In some variations, the responses can be pre-determined based upon a particular trigger. In such a case, stored response signals can he provided in upon a particular trigger. In this manner, instead of modifying the source signal, the circuit triggers a pre-determined response depending upon one or more characteristics of the source signal. The secondary circuit can also include a timer to output a response of limited duration.
Many systems could benefit from the implementation of haptics with capabilities for sound, (e.g. computers, smart phones, PDA's, electronic games). In this variation, filtered sound serves as the driving waveform for electroactive polymer haptics. The sound files normally used in these systems can be filtered to include only the optimal frequency ranges for the haptic feedback actuator designs.
Current systems operate at optimal frequencies of <200 Hz. A sound waveform, such as the sound of a shotgun blast, or the sound of a door closing, can be low pass filtered to allow only the frequencies from these sounds that are <200 Hz to be used. This filtered waveform is then supplied as the input waveform to the EPAM power supply that drives the haptic feedback actuator. If these examples were used in a gaming controller, the sound of the shotgun blast and the closing door would be simultaneous to the haptic feedback actuator, supplying an enriched experience to the game player.
In one variation use of an existing sound signal can allow for a method of producing a haptic effect in a user interface device simultaneously with the sound generated by the separately generated audio signal. For example, the method can include routing the audio signal to a filtering circuit; altering the audio signal to produce a haptic drive signal by filtering a range of frequencies below a predetermined frequency; and providing the haptic drive signal to a power supply coupled to an electroactive polymer transducer such that the power supply actuates the electroactive polymer transducer to drive the haptic effect simultaneously to the sound generated by the audio signal.
Another variation for driving an electroactive polymer transducer includes the use of stored wave forms given a threshold input signal. The input signal can include an audio or other triggering signal. For example, the circuit shown in
The electroactive polymer actuator used in the present disclosure can be controlled to operate between a pulse mode and a subwoofer mode depending upon the frequency of the signal output by the media device. Such a feature is useful to distinguish between repeatable effects (such as the typing on a keyboard) and effects produced during games or other by various other media.
In many cases, the system can limit power consumption using a circuit that cuts off or reduces voltage when the current draw is too high, e.g. at higher frequencies. In a first example, the second stage cannot run unless the input stage of the converter is above a given voltage. When the second stage initializes, the circuit causes the voltage on the first stage to drop and then drops out of the second stage if the input power is limited. At low frequencies, the haptic response follows the input signal. However, because high frequencies require more power, the response becomes clipped depending on the input power. Power consumption is one of the metrics needed to optimize the sub-assembly and drive design. Clipping the response in this manner conserves power.
In another variation, the drive scheme can employ amplitude modulation. For example, the actuator voltage can be driven at resonant frequency where the signal amplitude is scaled based on the input signal amplitude. This level is determined by the input signal, and the frequency is determined by the actuator design.
In another variation, the haptic response or effect can be tailored by the choice of the drive scheme, e.g. analog (as with the audio signal) or digital bursts or combinations of Filters or amplifiers can be used to enhance the frequencies in the input drive signal that leads to the highest performance of the actuators. This permits an increased sensitivity in the haptic response by the user and/or to accentuate the effect desired by the user. For example, the sub-assembly/system frequency response can be designed to match/overlap fast a fast Fourier transform taken of sound effects that are used as the drive input signal.
Another variation for producing a haptic effect involves the use of a roll-off filter. Such a filter allows attenuation of high frequencies that require a high power draw. To compensate for this attenuation, the sub-assembly can be designed to have its resonance at higher frequencies. The resonant frequency of the sub-assembly can be adjusted for example by changing the stiffness of the actuators (e.g. by changing the dielectric material, varying the thickness of the dielectric film, changing the type or thickness of the electrode material, changing the dimensions of the actuators), changing the number of cartridges in the actuator stack, changing the load or inertial mass on the actuators. Moving to thinner films or softer materials can move the cut-off frequency needed to meet a current/power limitation to higher frequencies. Clearly, adjustment of the resonance frequency can occur in any number of ways. The frequency response can also be tailored by using a mixture of actuator types.
Rather than using a simple follower circuit, a threshold can be used in the input drive signal to trigger a burst with an arbitrary waveform that requires less power. This waveform could be at a lower frequency and/or can be optimized with respect to the resonant frequency of the system—sub-assembly & housing—to enhance the response. In addition, the use of a delay time between triggers can also be used to control the power load.
In another variation, a control circuit can monitor input audio waveforms and provide control for a high voltage circuit. In such a case, as shown in
This control circuit changes high voltage based on zero crossing time and voltage swing direction. As shown in
Such a control circuit allows actuation events to coincide with frequency of the audio signal 510. In addition, the control circuit can allow for filtering to eliminate higher frequency actuator events to maintain 40-200 Hz actuator response range. The square wave provides the highest actuation response for inertial drive designs and can be set by the limit of the power supply components. The charge up time can be adjusted to limit power supply requirements. To normalize actuation forces, the mechanical resonance frequency can be charged by a Triangle wave, while off resonant frequency actuations can be energized by a square wave.
The circuit technology used to drive haptic electronics can be selected to optimize the footprint of the circuit (i.e. reduce the size of the circuit), increase the efficiency of the haptic actuator, and potentially reduce costs. The following Figures identify examples of such circuit diagrams.
As for other details of the present invention, materials and alternate related configurations may be employed as within the level of those with skill in the relevant art. The same may hold true with respect to method-based aspects of the invention in terms of additional acts as commonly or logically employed. In addition, though the invention has been described in reference to several examples, optionally incorporating various features, the invention is not to be limited to that which is described or indicated as contemplated with respect to each variation of the invention. Various changes may be made to the invention described and equivalents (whether recited herein or not included for the sake of some brevity) may be substituted without departing from the true spirit and scope of the invention. Any number of the individual parts or subassemblies shown may be integrated in their design. Such changes or others may be undertaken or guided by the principles of design for assembly.
Also, it is contemplated that any optional feature of the inventive variations described may be set forth and claimed independently, or in combination with any one or more of the features described herein. Reference to a singular item, includes the possibility that there are plural of the same items present. More specifically, as used herein and in the appended claims, the singular forms “a,” “an,” “said,” and “the” include plural referents unless the specifically stated otherwise. In other words, use of the articles allow for “at least one” of the subject item in the description above as well as the claims below. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation. Without the use of such exclusive terminology, the term “comprising” in the claims shall allow for the inclusion of any additional element—irrespective of whether a given number of elements are enumerated in the claim, or the addition of a feature could be regarded as transforming the nature of an element set forth in the claims. Stated otherwise, unless specifically defined herein, all technical and scientific terms used herein are to be given as broad a commonly understood meaning as possible while maintaining claim validity.
The present application claims priority to U.S. Provisional Application No. 61/301,177 filed Feb. 3, 2010 entitled “Haptic Grip Case”, the entirety of which is incorporated herein by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US11/00196 | 2/3/2011 | WO | 00 | 9/8/2014 |
Number | Date | Country | |
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61301177 | Feb 2010 | US |