TWI439919B - Electroactive polymer transducers for tactile feedback devices - Google Patents

Description

Electroactive polymer converter for tactile feedback devices

The present invention relates to providing sensing feedback using an electroactive polymer converter.

Many well-known user interface devices typically respond to one of the user's initial forces to apply tactile feedback (transmitting information to the user through the force applied to the user's body). Examples of user interface devices to which tactile feedback can be applied include keyboards, touch screens, computer mice, trackballs, sharp pens, joysticks, and the like. The tactile feedback provided by the type of interface device is in the form of a body sensation, such as vibration, pulsation, spring force, etc., which is directly (eg, via touch of the screen) by a user, indirectly (eg, via a mobile phone in one A vibration effect occurs when the wallet or handbag vibrates) or in other sensory manners (eg, by moving one of the moving bodies, which creates a pressure disturbance in the conventional sense but does not produce an audio signal).

Typically, a user interface device having tactile feedback can be an input device that "receives" one of the actions initiated by the user while providing an output device that indicates the tactile feedback that the action has initiated. In practice, by the force applied by the user, the position of certain contact or touch portions or surfaces (eg, buttons) of a user interface device is changed along at least one degree of freedom, wherein changing the position of the contact portion and affecting the tactile sense Feedback, the force applied must reach the minimum threshold. A change in the position of the contact portion that is achieved or registered results in a back stress (eg, rebound, vibration, pulsation) that is also applied to the contact portion of the device to which the user acts, which force is transmitted to the user through the tactile sensation of the user. By.

One common example of a user interface device that uses a rebound or "dual phase" type of tactile feedback is a button on a mouse. The button moves until the applied force reaches a certain threshold, at which point the button moves relatively easily and then stops, and the sense of the set is defined as "clicking" the button. The force applied by the user is substantially perpendicular to the axis of the button surface due to the responsive (relative) force felt by the user.

In another example, when a user enters on a touch screen, the screen typically confirms the input by a graphical change on the screen with/without the same audible prompt. A touch screen provides graphical feedback through visual cues on the screen, such as color or shape changes. A touchpad provides visual feedback through one of the cursors on the screen. While the above tips provide feedback, the most intuitive and effective feedback from a finger-initiated input device is a tactile feedback, such as a keyboard key stop device or a mouse wheel stop device. Therefore, it is necessary to incorporate tactile feedback on the touch screen.

Tactile feedback capabilities are known to improve user productivity and efficiency, especially in data logging environments. The inventors of the present invention have further improved this productivity and efficiency by further improving the characteristics and quality of the tactile sensation transmitted to a user. It would be more beneficial if one of the sensing feedback mechanisms was provided by the ease of low cost manufacturing to provide such improvements without increasing, preferably reducing, the space, size and/or quality requirements of known tactile feedback devices.

The present invention includes apparatus, systems, and methods involving an electroactive transducer for sensing applications. In one variation, a user interface device with sensing feedback is provided. One advantage of the present invention is that a touch feedback method is provided to a user of a touch screen or an electronic device equipped with a touch panel whenever one of the inputs on a sensor board is triggered or the actuator is triggered by a software. The touch screen can be rigid or flexible depending on the desired application for the user interface device.

In one variation, the system described herein includes a user interface device for displaying information to a user, the user interface device including a screen configured to provide a user or a sensor The panel is in tactile contact with a user interface surface, the screen being configured to display the information; a frame surrounding at least a portion of the screen; and an electroactive polymer material coupled to the screen and the frame Between the input of the signal by the user causing an electric field to be applied to the electroactive polymer material, which causes the electroactive polymer material to displace the screen in a manner sufficient to produce a force for the user to tactilely observe At least one of the panels with the sensor.

The user interface device described herein can be configured for tactile contact by a user, and wherein the input of the input signal is caused by tactile contact made by the user. Alternatively, or in addition, the user interface device can be configured to accept user input and for the generation of the input signal.

The systems described herein also typically include a control system for responding to a triggering force against one of the screens to control the amount of displacement of the electroactive polymer converter. The movement of the screen can be in any number of directions. For example, in a lateral direction with respect to one of the frames, with respect to the axial direction of the frame, or both.

In some variations, the electroactive polymer material is encapsulated to form a gasket, and wherein the gasket is mechanically coupled between the frame and the screen.

The electroactive polymer material can be coupled between the frame and the screen in any number of configurations. The coupling can include at least one spring member between the frame and the screen.

In some variations of the device, the electroactive polymer material comprises at least one electroactive transducer having at least one spring member.

In another variation, the electroactive polymer material comprises a plurality of wrinkles or folds.

In another variation of the user interface device, the device includes a screen having a sensor surface configured for tactile contact with a user or a sensor panel, the screen being configured to display The information; a frame surrounding at least a portion of the screen; and an electroactive polymer material coupled between the surface of the sensor and the frame, wherein an input signal is generated by the user An electric field is applied to the electroactive polymer material that causes the electroactive polymer material to displace at least one of the screen and the sensor panel in a manner that produces a force sufficient for the user to tactilely observe.

The apparatus and system of the present invention provides greater versatility as it can be applied to many input device types and provides feedback from multiple input components. This system is also advantageous because it does not substantially increase the mechanical complexity of the device or increase the mass and weight of the device. The system also performs its function without any mechanical sliding or rotating elements, making the system durable, easy to assemble and easy to manufacture.

The invention can be applied to any type of user interface device, including but not limited to a touchpad, a touch screen or a numeric keypad or for a computer, a telephone, a PDA, a video game console, a GPS system, a kiosk application, etc. Analogs.

With regard to other details of the invention, materials and alternating related configurations can be applied to the level of those skilled in the art. The method-based aspect of the present invention is equally effective in terms of additional actions for normal or logical applications. In addition, although the invention has been described in connection with a number of examples, the invention is not limited to the invention as described or illustrated in the context of the invention. The invention may be modified in various ways and equivalents may be substituted without departing from the spirit and scope of the invention. Any number of individual parts or subassemblies shown can be integrated into their design. These or other changes can be made or guided by the design principles used in the assembly.

These and other features, objects and advantages of the present invention will become apparent from the <RTIgt;

The apparatus, system and method of the present invention will now be described in detail with reference to the accompanying drawings.

As described above, devices that require a user interface can be improved by using tactile feedback on the user's screen of the device. 1A and 1B illustrate a simple example of such a device 190. Each device includes a display screen 232 for the user to input or view the material. The display screen is coupled to one of the body or frame 234 of the device. It is obvious that any number of devices are included in the scope of the present disclosure, whether or not they are portable (such as mobile phones, computers, manufacturing equipment, etc.) or fixed to other non-portable structures (such as a screen of an information display panel). , cash dispensers, etc.). For the purposes of this disclosure, a display screen can also include a touchpad type device in which user input or interaction occurs on a monitor or away from the actual touchpad (eg, a laptop touch Board).

Many design considerations have led to the selection and use of advanced dielectric elastomers (also known as "electroactive polymers" (EAP)) to make converters, especially when seeking to display tactile feedback of screen 232. These considerations include potential power, power density, power conversion/consumption, size, weight, cost, response time, duty cycle, service requirements, environmental impact, and more. Therefore, in many applications, EAP technology provides an ideal replacement for piezoelectric shape memory alloys (SMA) and electromagnetic devices such as motors and solenoids.

An EAP converter includes two thin film electrodes that have elastic properties and are separated by a thin elastic 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. When the electrodes are pulled closer together, the dielectric polymer film becomes thinner (z-axis component compression) due to expansion in the flat direction (x and y-axis component expansion).

2A-2B show a portion of a user interface device 230 having a display screen 232 having a surface that is responsive to information, control or stimulation on the screen for contact by the user entity. Display screen 234 can be any type of trackpad or screen panel, such as a liquid crystal display (LCD), organic light emitting diode (OLED), or the like. Additionally, changes to the interface device 230 can include a display screen 232 (eg, a "dummy" screen) on which an image (eg, a projector or graphics overlay) can be transposed, which can include a conventional monitor or even have A screen that holds information (such as common symbols or displays).

In any event, display screen 232 includes a frame 234 (or housing or any other structure that mechanically connects the screen to the device via a direct connection or one or more grounding elements) and an electroactive polymer ( An EAP converter 236 couples the screen 232 to the frame or housing 234. As described herein, the EAP converters can be placed along one edge of the screen 232, or an array of one of the EAP converters can be placed in contact with a portion of the screen 232 that is spaced away from the frame or housing 234.

2A and 2B illustrate a basic user interface device in which an encapsulated EAP converter 236 forms a movable washer. Any number of movable washers EAP 236 can be coupled between the touch screen 232 and the frame 234. Sufficient movable washer EAP 236 is typically provided to create the desired tactile feel. However, this amount will generally vary with the particular application. In one variation of the device, the touch screen 232 can include a display screen or a sensor board (where the display screen is behind the sensor board).

The figures show the user interface device 230 that the touch screen 232 cycles between inactive and active states. 2A shows a user interface device 230 in which the touch screen 232 is in an inactive state. In this case, no electric field is applied to the EAP converter 236, which allows the converters to be in a stationary state. 2B shows the user interface device 230 after a user input triggers the EAP converter 236 to an active state, wherein the converter 236 causes the display screen 232 to move in the direction indicated by arrow 238. Alternatively, the displacement of one or more of the EAP converters 236 can be varied to cause the display screen 232 to produce an azimuthal movement (eg, one area of the uniform movement screen 232 (rather than the entire display screen 232) can be displaced a greater extent than the other area. ). It will be apparent that one of the control systems coupled to the user interface device 230 can be configured to cycle the EAPs 236 at a desired frequency and/or change the amount of deflection of the EAP 236.

3A and 3B illustrate another variation of a user interface device 230 having a display screen 232 over a flexible film 240 for protecting the display screen 232. Likewise, the apparatus can include a plurality of movable washers EAP 236 that couple display screen 232 to a base or frame 234. In response to a user input, when an electric field is applied to the EAP 236, the screen 232 is displaced along with the film 240, causing displacement, causing the device 230 to enter an active state.

4 illustrates an additional variation of a user interface device 230 having a spring biased EAP film 240 positioned adjacent one edge of the display screen 232. The EAP film 240 can be placed near one of the perimeters of the screen or only at a location that allows the screen to produce tactile feedback to the user. In this variation, a passive compliant washer 244 provides a force against the screen 232 such that the EAP film 242 is in a tensioned state. After providing an electric field 242 to the thin film (again, after a signal is generated by a user input), the EAP film 242 relaxes causing displacement of the screen 232. As indicated by arrow 246, user input device 230 can be configured to cause movement of screen 232 in any direction relative to the bias provided by washer 244. In addition, actuation of less than all of the EAP film 242 causes the screen 232 to produce non-uniform movement.

FIG. 5 illustrates another variation of a user interface device 230. In this example, a plurality of compliant washers 244 are used to couple display screen 232 to a frame 234 and the driving force for display 232 is a plurality of EAP actuator diaphragms 248. The EAP actuator diaphragm 248 is spring biased and can drive the display screen after application of an electric field. As shown, the EAP actuator diaphragm 248 has a relatively EAP film on either side of a spring. In this configuration, the opposite side of the EAP actuator diaphragm 248 is activated such that the assembly is strictly at a neutral point. The EAP actuator diaphragms 248 act as the biceps and triceps, which act to control the movement of the human arm. Although not shown, the actuator diaphragms 248 can be stacked to provide a two-phase output action and/or to amplify the output for use in a more robust application, as described in U.S. Patent Application Serial Nos. 11/085,798 and 11/085,804. .

6A and 6B show another variation of a user interface 230 having an EAP film or film 242 coupled between a display 232 and a frame 234 at a plurality of points or ground elements 252. To accommodate wrinkles or folds in the EAP film 242. As shown in FIG. 6B, applying an electric field to the EAP film 242 causes the display screen 232 to be displaced in the wrinkle direction or deflected relative to the frame 240. The user interface 232 can include a biasing spring 250, as desired, also coupled between the display 232 and the frame 234 and/or a flexible protective film 240 that covers a portion (or all) of the display screen 232.

It should be noted that the above figures schematically illustrate an exemplary configuration of such a tactile feedback device employing an EAP film or converter. Many variations, such as variations of the device, are within the scope of the present disclosure, and implementing an EAP converter can move only one sensor board or component (eg, triggering after user input and providing a signal to one of the EAP converters) Component) Instead of the entire screen or board assembly.

In any application, the feedback displacement of a display screen or sensor panel by the EAP component can be specifically in a plane that senses lateral movement, or can be out of plane (eg, sensed as a vertical displacement). Alternatively, the EAP converter material can be segmented to provide an addressable/movable section independently to provide angular displacement of the plate element. In addition, any number of EAP converters or membranes can be incorporated into the user interface devices described herein (as disclosed in the applications and patents listed above).

Variations in the devices described herein allow the entire sensor panel (or touch screen) of the device to be used as a haptic feedback element. This allows for a wide range of functionality. For example, in response to a virtual key tapping the screen, the screen can be bounced once or it can be returned to one of the scroll elements (eg, a slider) on the screen to output a continuous bounce to effectively simulate a roller mechanical stop device. By using a control system, a three-dimensional structure can be simulated by reading a precise position of a user's finger on the screen and moving the screen panel accordingly to simulate a three-dimensional structure. Assuming that there is sufficient screen displacement and the screen has significant quality, the repeated oscillation of the screen can even replace the vibration function of a mobile phone. This functionality can be used to browse text in which a tactile "bump" is used to represent the (vertical) scrolling of a line of text, thereby simulating the stop device. In the context of video games, the present invention provides more interactivity and finer motion control in the oscillating vibration motor used in prior art video game systems. In the case of a touchpad, user interaction and accessibility can be improved by providing physical hints, especially for visually impaired people.

The EAP converter can be configured to shift in proportion to an applied voltage, which helps to program a control system for use with the subject's tactile feedback device. For example, a software algorithm can convert the pixel grayscale to an EAP converter displacement, thereby continuously measuring the pixel grayscale value at the tip of the screen cursor and translating it into a proportional displacement by the EAP converter. A user can feel or sense a substantially three-dimensional tissue by moving a finger across the touchpad. A similar algorithm can be applied to a web page, wherein after moving a finger on an icon, the border of the icon is fed back to the user as a bump or a buzz button in the web page organization. For normal users, this will provide a completely new sensing experience, which adds indispensable feedback to visually impaired viewers browsing the site.

EAP converters are well suited for these applications for a number of reasons. For example, because EAP converters are lightweight and have minimal components, they provide an extremely low profile and are therefore well suited for use in sensing/tactile feedback applications. Examples of EAP converters and their construction are described in U.S. Patent Nos. 7,368,862, 7,362,031, 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, 2007/0200468, 2007/0200467, 2007/0200466, 2007/0200457, 2007/0200454, 2007/0200453, 2007/0170822, 2006/0238079, 2006/0208610, 2006/0208609 and 2005/0157893, all of these cases The content is incorporated herein by reference.

7A and 7B illustrate an example of the structure of an EAP film or film 10. A thin elastic dielectric film or layer 12 is sandwiched between compliant or bendable electrode plates or layers 14 and 16 to form a capacitive structure or film. The length "l" and the width "w" of the dielectric layer and the length and width of the composite structure are much larger than the thickness "t". Typically, the dielectric layer has a thickness in the range of from about 10 [mu]m to about 100 um, and the total thickness of the structure is in the range of from about 25 [mu]m to about 10 cm. In addition, the elastic modulus, thickness, and/or micro-geometry of the electrodes 14, 16 need to be selected such that the additional hardness contributed to the actuator is typically lower than the hardness of the dielectric layer 12, which has a relative A low modulus of elasticity (e.g., less than about 100 MPa and typically less than about 10 MPa), but may be thicker than each electrode. Electrodes suitable for such compliant capacitive structures are capable of withstanding cyclic stresses greater than about 1% without failure due to mechanical fatigue.

As can be seen from Figure 7B, when a voltage is applied across the electrodes, the different charges in the two electrodes 14, 16 will attract each other and the electrostatic attraction compresses the dielectric film 12 (along the Z-axis). This causes the dielectric film 12 to deflect as the electric field changes. Since the electrodes 14, 16 are compliant, their shape varies with the dielectric layer 12. In general, deflection refers to any displacement, expansion, contraction, torsion, linear or regional stress, or any other deformation of a portion of dielectric film 12. The deflection can be used to generate mechanical work according to a form in which the capacitive structure 10 (collectively referred to as a "converter") is used to fit the architecture (eg, a frame). A variety of different converter architectures are disclosed and illustrated in the above patent references.

By applying a voltage, the converter film 10 is continuously deflected until the mechanical force balances the electrostatic force that drives the deflection. These mechanical forces include the elastic restoring force of the dielectric layer 12, the compliance or stretching of the electrodes 14, 16 and any external resistance provided by the device and/or load coupled to one of the transducers 10. The resulting deflection of the converter 10 due to the applied voltage can also depend on many other factors, such as the dielectric constant of the elastomeric material and its magnitude and hardness. Removing the voltage difference and the introduced charge results in a counter effect.

In some cases, electrodes 14 and 16 may cover a limited portion of the film relative to the total area of dielectric film 12. This prevents electrical breakdown around the edge of the dielectric or deflection of the custom in its particular portion. During deflection, a movable region (which is a portion of the dielectric material that has sufficient electrostatic force to deflect the portion) can be used as an external spring force on the active region. More specifically, the material outside the active area can resist or enhance the deflection of the active area by its contraction or expansion.

The dielectric film 12 can be strained in advance. This pre-strain improves the transition between electrical energy and mechanical energy, i.e., the pre-strain allows the dielectric film 12 to deflect more and provide greater mechanical work. The pre-strain of a film can be described as the dimension in that direction after pre-straining relative to the dimension in one direction before pre-strain. The pre-strain may comprise elastic deformation of the dielectric film and may be formed, for example, by stretching the film under tension and fixing one or more edges while stretching. The pre-strain can be applied at the boundary of the film or only for a portion of the film, and the pre-strain can be performed by using a rigid frame or by hardening a portion of the film.

The details of the converter structure and other similar compliant structures of Figures 7A and 7B and their concepts are more fully described in the many referenced patents and publications disclosed herein.

In addition to the EAP film described above, the sensing or tactile feedback user interface device can include an EAP converter designed to produce lateral movement. For example, as shown in Figures 8A and 8B, from top to bottom, including various components of the actuator 30, the actuator 30 has an electroactive polymer (EAP) converter 10 in the form of an elastic film that converts electrical energy into Mechanical energy (as described above). The resulting mechanical energy is in the form of a physical "displacement" of an output member, here in the form of a disc 28.

Referring to Figures 9A through 9C, the EAP converter film 10 includes two working pairs of thin elastic electrodes 32a, 32b and 34a, 34b, each of which is separated by a thin layer 26 of elastomeric dielectric polymer (e.g., by acrylic, poly Made of helium, polyethylene polyacrylate, thermoplastic elastomer, hydrocarbon rubber, fluoroelastomer or the like). When a voltage difference is applied to each of the oppositely charged electrodes (e.g., across electrodes 32a and 32b, and across electrodes 34a and 34b), the opposing electrodes attract each other to compress the dielectric polymer therebetween. Layer 26. When the electrodes are pulled closer together, the dielectric polymer 26 becomes thinner (i.e., the z-axis component shrinks) due to expansion in the flat direction (i.e., the x and y-axis component expansion) (see Figure 9B). And the axis reference of 9C). In addition, the same charge distributed on each electrode causes the conductive particles embedded in the electrode to repel each other, resulting in expansion of the elastic electrode and the dielectric film. This causes the dielectric layer 26 to deflect as the electric field changes. Since the electrode materials are also compliant, the electrode layers change shape with the dielectric layer 26. In general, deflection refers to any displacement, expansion, contraction, torsion, linear or regional stress, or any other deformation of a portion of dielectric layer 26. This deflection can be used to generate mechanical work.

In making the transducer 20, the elastic film is stretched and held under pre-strain conditions by two relatively rigid frame sides 8a, 8b. It has been found that the pre-strain improves the dielectric strength of the polymer layer 26, thereby improving the conversion between electrical energy and mechanical energy, i.e., the pre-strain allows the film to deflect more and provide greater mechanical work. The electrode material is typically applied after the pre-strained polymer layer, but may also be applied in advance. Two electrodes are provided on the same side of layer 26 (herein referred to as electrode pairs on the same side, electrodes 32a and 34a on top side 26a of dielectric layer 26 (see Figure 9B) and dielectric layer 26 The electrodes 32b and 34b (see Fig. 9C) on the bottom side 26b are electrically insulated from each other by an inactive area or gap 25. The opposing electrodes on opposite sides of the polymer layer are from two sets of working electrode pairs, namely electrodes 32a and 32b in one working electrode pair and electrodes 34a and 34b in the other working electrode pair. Each of the same side electrode pairs preferably has the same polarity, and the electrodes of each working electrode pair are opposite in polarity, i.e., electrodes 32a and 32b are oppositely charged, and electrodes 34a and 34b are oppositely charged. Each electrode has an electrical contact portion 35 that is configured for electrical connection to a voltage source (not shown).

In the particular embodiment shown, each electrode has a semi-circular configuration in which the same pair of side electrodes define a substantially circular pattern for receiving a centrally disposed arrangement on each side of the dielectric layer 26. The rigid output discs 20a, 20b. The discs 20a, 20b are secured to the centrally exposed outer surfaces 26a, 26b of the polymer layer 26 to sandwich the layers 26 therebetween, the function of which is discussed below. The coupling between the disc and the membrane can be mechanical or can be provided by an adhesive. In general, the size of the discs 20a, 20b is adjusted relative to the converter frames 22a, 22b. More specifically, the ratio of the diameter of the disc to the diameter of the inner ring of the frame should be such as to sufficiently distribute the stress applied to the converter film 10. The greater the ratio of the diameter of the disc to the diameter of the frame, the greater the force of the feedback signal or movement, and the lower the linear displacement of the disc. Alternatively, the lower the ratio, the lower the output force and the greater the linear displacement.

Depending on the electrode configuration, the converter 10 can function in a single or a dual phase mode. In the configured manner, the mechanical displacement of the output components of the target sensing feedback device (i.e., the two coupled disks 20a and 20b) is lateral rather than vertical. In other words, the sensing feedback or output force of the sensing/tactile feedback device of the present invention (shown by the double-headed arrow 60b in FIG. 10) is in a direction parallel to the display surface 232 and perpendicular to the input force 60a. The sense feedback signal is not in a direction perpendicular to the display surface 232 of the user interface and parallel to the input force (in the opposite or upward direction) applied by the user's finger 38 (as indicated by the arrow in FIG. 10) The force shown in 60a). Depending on the rotational alignment of the electrode pair about an axis perpendicular to the plane of the transducer 10 and relative to the position of the display surface 232 in the mode (ie, single phase or two phases) used to operate the transducer, this lateral movement can be 360. In any direction within. For example, the lateral feedback action can be relative to the direction of advancement of the user's finger (or palm or handle, etc.), from side to side or from top to bottom (both are two-phase actuation). While those skilled in the art will appreciate certain other actuator configurations that provide feedback displacement across one of the contact surfaces of the tactile feedback device, the overall distribution of one of the devices so configured is greater than the foregoing design.

Figures 9D through 9G illustrate an example of one of an array of electroactive polymers that can be placed across the display screen of the device. In this example, the voltage and ground sides 200a and 220b of an EAP film array 200 used in an array of EAP actuators for use in the haptic feedback device of the present invention are shown, respectively (see Figure 9F). Membrane array 200 includes an array of electrodes that are provided in a matrix configuration to increase space and power efficiency. The high voltage side 200a of the EAP film array provides an electrode pattern 202 that extends vertically over the material of the dielectric film 208 (according to the viewpoint shown in Figure 9D). Each pattern 202 includes a pair of high voltage lines 202a, 202b. The opposite or ground side 200b of the EAP mode provides an electrode pattern 206 that operates laterally (i.e., horizontally) relative to the high voltage electrode. Each pattern 206 includes a pair of ground lines 206a, 206b. Each pair of relatively high voltage and ground lines (202a, 206a and 202b, 206b) provides a separately actuatable electrode pair such that the pair of opposing electrode pairs provide a two phase output action in the direction indicated by arrow 212. In FIG. 9F, in an exploded view of an array 204 of one of the EAP converters 222, an assembled EAP film array 200 (electrode pattern displayed on the top and bottom sides of the dielectric film 208) is provided, the EAP conversion An array of one of the devices is illustrated in assembly form in Figure 9G. The EAP film array 200 is sandwiched between opposing frame arrays 214a, 214b, wherein each individual frame segment 216 within each of the two arrays is defined by a centrally located one of the output disks 218 in an open region. Each combination of frame/disc segment 216 and electrode configuration forms an EAP converter 222. Additional component layers can be added to the transducer array 204 depending on the desired application and the type of actuator. The transducer array 220 can be integrated into a user interface array, such as a display screen, sensor surface, or trackpad.

When the sensing/tactile feedback device 2 is operated in a single phase mode, only one of the working pairs of the actuators 30 is activated at any one time. A single phase operation of the actuator 30 can be controlled using a single high voltage power supply. When the voltage applied to the single selected pair of working electrodes is increased, the starting portion (half) of the converter film will expand to move the output disk 20 in a plane in the direction of the inactive portion of the converter film. Figure 11A illustrates the force versus stroke of the sense feedback signal (i.e., output disc displacement) of the actuator 30 relative to the neutral position when the two working electrode pairs are alternately activated in a single phase mode. As shown, the respective forces and displacements of the output discs are equal to each other in opposite directions. Figure 11B illustrates the resulting nonlinear relationship between the output displacement of the actuator operating in this single phase mode and the applied voltage. The "mechanical" coupling of the two electrode pairs by a common dielectric film can be used, for example, to move the output disc in the opposite direction. Therefore, when operating two electrode pairs, although independent of each other, applying a voltage to the first working electrode pair (phase 1) will move the output disk 20 in one direction and apply a voltage to the second working electrode pair (phase 2) The output disc 20 will be moved in the opposite direction. As reflected in the various plots of Figure 11B, when the voltage changes linearly, the displacement of the actuator is non-linear. The acceleration of the output disc during the displacement can also be controlled by the synchronization operation of the two phases to enhance the tactile feedback effect. The actuator can also be split into more than two phases that can be independently activated to enable more complex actions of the output disc.

To achieve greater displacement of one of the output members or components, and thus to provide a larger sense feedback signal to the user, the actuator 30 is operated in a two phase mode, i.e., the two portions of the actuator are simultaneously activated. Figure 12A illustrates the force versus stroke of the sense feedback signal of the output disc when the actuator is operated in the two phase mode. As shown, the forces and strokes of the two portions 32, 34 of the actuator in this mode are in the same direction and have an amplitude that is the force of the actuator when operating in a single phase mode. It is twice the magnitude. Figure 12B illustrates the resulting linear relationship between the output displacement of the actuator and the applied voltage when operating in the two phase mode. The portion 32, 34 of the mechanical coupling of the actuator is electrically connected in series and its common electrode 55, the voltage of the common electrode 55 and the output member (for any) are controlled, for example, in the manner shown in block 40 of FIG. The relationship between the displacement (or blocking force) of the configuration) achieves a linear correlation. In this mode of operation, the non-linear voltage responses of the two portions 32, 34 of the actuator 30 effectively cancel each other out to produce a linear voltage response. By using control circuitry 44 for each portion of the actuator and switching assemblies 46a, 46b, this linear relationship allows for fine tuning by using different types of waveforms supplied to the switch assemblies by the control circuitry. And the performance of the actuator is modulated. Another advantage of using circuit 40 is that it reduces the number of switching circuits and power supplies required to operate the sensing feedback device. Without the use of circuit 40, two separate power supplies and four switching assemblies are required. Therefore, reducing the complexity and cost of the circuit while improving the relationship between the control voltage and the actuator displacement, that is, making it more linear.

Various types of mechanisms can be applied to communicate the input force 60a from the user to achieve the desired sensing feedback 60b (see Figure 10). For example, a capacitive or resistive sensor 50 (see FIG. 13) can be loaded in the user interface panel 4 to sense the mechanical force exerted by the user on the user contact surface input. Depending on the mode and waveform provided by the control circuit, the electrical output 52 is supplied from the sensor 50 to the control circuit 44, which in turn triggers the switch assemblies 46a, 46b to apply the voltage from the power supply 42 to the respective sensing feedback devices. Converter sections 32, 34.

Another variation of the invention relates to a closed sealed EAP actuator to minimize any effects of moisture or moisture condensation that may occur on the EAP film. For the various embodiments described below, the EAP actuator is sealed in a barrier film that is substantially separate from the other components of the haptic feedback device. The barrier film or outer casing may be made, for example, of a foil, which is preferably heat sealed or similar to minimize moisture leakage into the sealing film. The barrier film or portions of the outer casing may be made of a compliant material to allow for improved mechanical coupling of the actuator within the outer casing to a point outside the outer casing. Each of the device embodiments can couple the feedback action of the output member of the actuator to the contact surface of the user input surface (e.g., a numeric keypad) while minimizing the actuator package in the hermetic seal Any damage. Various exemplary methods for coupling the action of the actuator to the user interface contact surface are also provided. In terms of methods, the primary methods can include each of the machinery and/or activities associated with the use of the device. Also, the method implicitly uses the device to form part of the invention. Other methods focus on the manufacture of such devices.

FIG. 14A shows an example of a flat array of one of the EAP actuators 204 coupled to a user input device 190. As shown, the array of EAP actuators 204 covers a portion of screen 232 and is coupled to one of the frames 234 of device 190 via a bracket 256. In this variation, the bracket 256 provides a spacing for the movement of the actuator 204 and the screen 232. In one variation of device 190, the array of actuators 204 can be a plurality of discrete actuators or an array of actuators behind the user interface surface or screen 232, depending on the desired application. Figure 14B shows a bottom view of the device 190 of Figure 14A. As indicated by arrow 254, the EAP actuator 204 can allow the screen 232 to move along an axis as an alternative to or in combination with one of the movements in one direction perpendicular to the screen 232.

With regard to other details of the invention, materials and alternating related configurations can be applied to the level of those skilled in the art. In general, or in terms of other actions of the logic application, the method-oriented aspect of the present invention is equally effective. In addition, while the invention has been described with respect to a number of examples, the various features of the present invention are not limited to the invention as described or illustrated for each variation of the invention. The invention may be modified in various ways and equivalents may be substituted without departing from the spirit and scope of the invention. Any number of individual parts or subassemblies shown can be integrated into their design. These or other changes can be made or guided by the design principles used in the assembly.

Likewise, it is contemplated that any optional feature of the described variations of the invention can be made and claimed in combination with any one or more of the features described herein. A reference to a single item includes the possibility of having multiple identical items. Rather, the singular forms "a", "the" and "the" In other words, in the present description and the scope of the following claims, the use of the articles is intended to mean "at least one" item. It should be further noted that the scope of such patent applications can be drafted to exclude any optional components. Again, this expression is intended to be used as a basis for the use of such specific terms (such as "individual" or "only" and the like) or in conjunction with a "negative" limitation. In the absence of such proprietary terms, the term "comprising" in the scope of the claims should include any additional elements, whether or not a given number of elements are listed in the scope of the application, or a A feature can be considered as a property of one of the components proposed in the scope of the patent application. Otherwise, all technical and scientific terms used herein are given as broadly as are generally understood, unless the context clearly dictates otherwise.

In general, the breadth of the present invention is not limited to the examples provided. That is, the following patent claims are claimed.

2. . . Sensory/tactile feedback device

4. . . User interface panel

8a. . . Rigid frame side

8b. . . Rigid frame side

10. . . Converter film / converter / EAP film or film / capacitor structure

12. . . Dielectric layer/film

14. . . Electrode (plate)

16. . . Electrode (plate)

20a. . . Disc

20b. . . Disc

22a. . . Converter frame

22b. . . Converter frame

25. . . gap

26. . . Dielectric polymer layer

26a. . . Top side of outer surface/dielectric layer 26

26b. . . Bottom side of outer surface/dielectric layer 26

28. . . Disc

30. . . Actuator

32. . . Part of the actuator

32a. . . Elastic electrode

32b. . . Elastic electrode

34. . . Part of the actuator

34a. . . Elastic electrode

34b. . . Elastic electrode

35. . . Electrical contact

38. . . finger

42. . . power supply

44. . . Control circuit

46a. . . Switch assembly

46b. . . Switch assembly

50. . . Sensor

52. . . Electrical output

55. . . Common electrode

60a. . . Input force

60b. . . Feeling feedback

190. . . User input device

200a. . . Voltage side

200b. . . Ground side

202a. . . High voltage line

202b. . . High voltage line

204. . . Converter Array / EAP Actuator

206. . . Electrode pattern

206a. . . Ground wire

206b. . . Ground wire

208. . . Dielectric film

214a. . . Frame array

214b. . . Frame array

216. . . Frame fragment

218. . . Output disc

220. . . Converter array

222. . . EAP converter

230. . . User interface device

232. . . Display surface / display / display

234. . . frame

236. . . EAP converter

240. . . Flexible film

242. . . EAP film

244. . . Passive compliance washer

248. . . EAP actuator diaphragm

250. . . Bias spring

252. . . Grounding element

256. . . support

The invention may be best understood from the above detailed description when read in conjunction with the accompanying drawings. To promote understanding, the same reference numerals have been used (wherever practicable) to designate similar elements in the drawings. The following figures are included in the schema:

1A and 1B illustrate some examples of a user interface to which tactile feedback can be applied when an EAP converter is coupled to a display screen or sensor and one of the bodies of the device.

2A and 2B show a cross-sectional view of a user interface device including a display screen having a surface that is responsive to a tactile feedback response to a user input.

3A and 3B illustrate a cross-sectional view of another variation of a user interface device having a display screen covered by a flexible film having a movable EAP formed as a movable gasket.

4 illustrates a cross-sectional view of another variation of a user interface device having a spring biased EAP film positioned adjacent one edge of the display screen.

Figure 5 shows a cross-sectional view of a user interface device in which a plurality of compliant gaskets are used to couple the display screen to a frame and the driving force for display is a plurality of EAP actuator diaphragms.

Figures 6A and 6B show cross-sectional views of a user interface 230 of a undulating EAP film or film coupled between a display.

7A and 7B illustrate top perspective views of a transducer applied to a voltage before and after, in accordance with an embodiment of the present invention.

8A and 8B show exploded top and bottom perspective views, respectively, of a sensing feedback device for use in a user interface device.

Figure 9A is a top plan view of one of the electroactive polymer converters assembled in accordance with the present invention; Figures 9B and 9C are top and bottom plan views, respectively, of the membrane portion of the actuator of Figure 8A, in particular, the actuator is illustrated The second phase configuration.

Figures 9D and 9E illustrate an example of an array of electroactive polymer converters placed across a surface of a display screen spaced from a frame of the device.

9F and 9G are exploded and assembled views, respectively, of an array of actuators used in one of the user interface devices disclosed herein.

Figure 10 illustrates a side view of a user interface device and a human finger in operative contact with a contact surface of the device.

Figures 11A and 11B graphically illustrate the force versus stroke and voltage response curves of the actuators of Figures 9A through 9C, respectively, when operating in a single phase mode.

Figures 12A and 12B graphically illustrate the force versus stroke and voltage response curves of the actuators of Figures 9A through 9C, respectively, when operating in a two phase mode.

Figure 13 is a block diagram of a circuit including power supply and control electronics for operating one of the sensing feedback devices.

14A and 14B show a partial cross-sectional view of one example of a flat array of EAP actuators coupled to a user input device.

Variations of the invention are contemplated from the figures.

190. . . User input device

204. . . Converter Array / EAP Actuator

232. . . Display surface / display / display screen

234. . . frame

256. . . support

Claims (37)

A user interface device for displaying information to a user, the user interface comprising: a screen having a user interface surface configured to provide a user with tactile contact and a sensor panel, The screen is configured to display the information; a frame surrounding at least a portion of the screen; and an electroactive polymer material coupled between the screen and the frame, wherein the user generates An input signal applies an electric field to the electroactive polymer material that causes the electroactive polymer material to displace at least one of the screen and the sensor panel in a manner sufficient to produce a force sufficient for the user to tactilely observe By. The user interface device of claim 1, wherein the screen is configured for tactile contact by a user, and wherein the input of the input signal is caused by tactile contact made by the user. The user interface device of claim 1, wherein a data entry surface is configured to accept user input and for use in generating the input signal. The user interface device of claim 1 further comprising a control system for controlling the amount of displacement of the electroactive polymer converter in response to a triggering force against one of the screens. The user interface device of claim 1, wherein the movement of the screen is in a lateral direction relative to one of the frames. The user interface device of claim 1, wherein the output member is mechanically coupled to the user contact surface. The user interface device of claim 1, wherein the electroactive polymer material is encapsulated to form a gasket, and wherein the gasket is mechanically coupled between the frame and the screen. The user interface device of claim 1, wherein the electroactive polymer material is directly coupled between the frame and the screen. The user interface device of claim 8 further comprising at least one spring member between the frame and the screen. The user interface device of claim 1, further comprising a flexible layer covering at least a portion of the screen. The user interface device of claim 1, wherein the electroactive polymer material comprises at least one electroactive transducer having at least one spring member. The user interface device of claim 11, wherein the electroactive transducer comprises at least one pair of relatively electroactive polymer membranes. The user interface device of claim 11, wherein the electroactive transducer further comprises at least a negative spring rate bias. The user interface device of claim 1, wherein the electroactive polymer material is coupled to the display screen at a plurality of locations. The user interface device of claim 14, wherein the electroactive polymer material comprises a plurality of wrinkles or folds. The user interface device of claim 1, wherein the electroactive polymer material comprises an array of electroactive polymer materials adjacent at least a portion of the screen spaced from the frame. The user interface device of claim 1, wherein the screen comprises a touch panel. A user interface device for displaying information to a user, the user interface comprising: a screen having a sensor surface configured to provide a user with tactile contact and a sensor panel, The screen is configured to display the information; a frame surrounding at least a portion of the screen; and an electroactive polymer material coupled between the sensor surface and the frame, wherein the user is Generating an input signal to apply an electric field to the electroactive polymer material that causes the electroactive polymer material to displace the screen and the sensor surface in a manner sufficient to produce a force sufficient for the user to tactilely observe At least one. The user interface device of claim 18, wherein the sensor surface is configured for tactile contact by a user, and wherein the input of the input signal is caused by tactile contact made by the user. A user interface device of claim 18, wherein a data entry surface is configured to accept user input and for use in generating the input signal. The user interface device of claim 18, further comprising a control system for controlling the amount of displacement of the electroactive polymer converter in response to a triggering force against one of the sensor plates. The user interface device of claim 18, wherein the movement of the sensor panel is in a lateral direction relative to one of the frames. The user interface device of claim 18, wherein the output member is mechanically coupled to the user contact surface. The user interface device of claim 18, wherein the electroactive polymer material is encapsulated to form a gasket, and wherein the gasket is mechanically coupled between the frame and the sensor surface. The user interface device of claim 18, wherein the electroactive polymer material is directly coupled between the frame and the sensor surface. The user interface device of claim 25, further comprising at least one spring member between the frame and the surface of the sensor. The user interface device of claim 18, further comprising a flexible layer covering at least a portion of the screen. The user interface device of claim 18, wherein the electroactive polymer material comprises at least one electroactive transducer having at least one spring member. The user interface device of claim 28, wherein the electroactive transducer comprises at least one pair of relatively electroactive polymer membranes. The user interface device of claim 28, wherein the electroactive transducer further comprises a negative spring rate bias. The user interface device of claim 18, wherein the electroactive polymer material is coupled to the display screen at a plurality of locations. The user interface device of claim 31, wherein the electroactive polymer material comprises a plurality of wrinkles or folds. The user interface device of claim 18, wherein the sealing material forms a gasket between the user contact surface and the transducer. The user interface device of claim 18, wherein the sealing material covers the converter. The user interface device of claim 18, wherein the electroactive polymer material is activated in two phases. The user interface device of claim 18, wherein the electroactive polymer material comprises an array of electroactive polymer materials adjacent at least a portion of the sensor surface spaced from the frame. The user interface device of claim 18, wherein the screen comprises a touch panel.