METHOD AND APPARATUS FOR CONTROLLING GENERATION OF ELECTROSTATIC FRICTION EFFECTS FOR A PLURALITY OF ELECTRODES
An interface device configured to provide an electrostatic friction (ESF) effect is disclosed. The interface device comprises a plurality of electrodes disposed at a surface of the interface device. It further comprises a signal generating circuit configured to generate a first drive signal at an output of the signal generating circuit, and comprises a plurality of frequency filter units or delay elements electrically connected to the signal generating circuit and to the plurality of electrodes. The interface device further comprises a control unit configured to use the plurality of frequency filter units or delay elements: (i) to cause only a subset of one or more electrodes of the plurality of electrodes to output one or more respective ESF effects with the first drive signal, or (ii) to cause at least two electrodes to output respective ESF effects with the first drive signal in different respective manners.
The present invention is directed to a method and apparatus for controlling generation of electrostatic friction effects for a plurality of electrodes, and has application in wearables, user interfaces, gaming, automotive, virtual reality or augmented reality, and consumer electronics.
BACKGROUNDAs computer-based systems become more prevalent, the quality of the interfaces through which humans interact with these systems is becoming increasingly important. Haptic feedback, or more generally haptic effects, can improve the quality of the interfaces by providing cues to users, providing alerts of specific events, or providing realistic feedback to create greater sensory immersion within a virtual environment.
Examples of haptic effects include kinesthetic haptic effects (such as active and resistive force feedback), vibrotactile haptic effects, and electrostatic friction haptic effects. In electrostatic friction haptic effects, a current may be provided to an electrode. The electrode may then exert an attractive force on the skin of a user, who may perceive this force as electrostatic friction.
SUMMARYOne aspect of the embodiments herein relates to an interface device configured to provide an electrostatic friction (ESF) effect. The interface device comprises a plurality of electrodes, a signal generating circuit, a plurality of frequency filter units or delay elements, and a control unit. The plurality of electrodes are disposed at a surface of the interface device. The signal generating circuit is configured to generate a first drive signal at an output of the signal generating circuit. The plurality of frequency filter units or delay elements are electrically connected to the signal generating circuit and to the plurality of electrodes, such that each electrode of the plurality of electrodes is electrically connected to an output of a respective frequency filter unit or delay element. An input of the respective frequency filter unit or delay element is electrically connected to the output of the signal generating circuit. The control unit is configured to use the plurality of frequency filter units or delay elements: (i) to cause only a subset of one or more electrodes of the plurality of electrodes to output one or more respective ESF effects with the first drive signal, or (ii) to cause at least two electrodes of the plurality of electrodes to output respective ESF effects with the first drive signal in different respective manners.
In an embodiment, the interface device comprises the plurality of frequency filter units. Each of the plurality of frequency filter units has a respective pass-through frequency band or a respective set of pass-through frequency bands, and is configured to block any frequency component of the first drive signal which is outside the respective pass-through frequency band or respective set of pass-through frequency bands. The respective pass-through frequency bands or respective sets of pass-through frequency bands of the plurality of frequency filter units do not overlap in frequency, or only partially overlap in frequency.
In an embodiment, the control unit is configured to cause the signal generating circuit to generate the first drive signal with only a frequency component that is (i) within the respective pass-through frequency band or respective set of pass-through frequency bands of a respective frequency filter unit of a first electrode and (ii) outside the respective pass-through frequency bands or respective sets of pass-through frequency bands of the remainder of the plurality of frequency filter units of the remainder of the plurality of electrodes of the interface device, such that the plurality of frequency filter units causes only the first electrode of the plurality of electrodes to output an ESF effect with the first drive signal.
In an embodiment, each of the plurality of frequency filter units has only a single respective pass-through frequency band, and the respective pass-through frequency bands of the plurality of frequency filter units do not overlap in frequency, or each of the plurality of frequency filter units has a respective set of pass-through frequency bands, and the respective sets of pass-through frequency bands of the plurality of frequency filter units have partial overlap in frequency.
In an embodiment, the plurality of frequency filter units comprise a first frequency filter unit configured to pass the first drive signal to a first electrode of the plurality of electrodes with a first attenuation level, and comprises a second frequency filter unit configured to pass the first drive signal to a second electrode of the plurality of electrodes with a second attenuation level different than the first attenuation level. The interface device is configured to cause the first electrode and the second electrode to output respective ESF effect with the first drive signal with different respective intensity levels.
In an embodiment, the plurality of frequency filter units comprise a first frequency filter unit configured to pass the first drive signal to a first electrode of the plurality of electrodes with a first phase shift that creates a first period of delay, and comprises a second frequency filter unit configured to pass the first drive signal to a second electrode of the plurality of electrodes with a second phase shift that creates a second period of delay different than the first period of delay, and wherein the interface device is configured to cause the first electrode and the second electrode to output respective ESF effects with the first drive signal at different respective times.
In an embodiment, the control unit is configured to determine a spatial relationship between the interface device and a determined location, or to determine a temporal relationship between a current time and a determined event, and is configured to select the subset of one or more electrodes to convey the spatial relationship or the temporal relationship.
In an embodiment, the interface device comprises the plurality of frequency filter units. The first drive signal is one of a plurality of drive signals the signal generating circuit is configured to generate in different respective time periods or in response to different signal generating commands. The control unit is configured to cause the plurality of frequency filter units to pass the plurality of drive signals to different respective electrodes of the plurality of electrodes.
In an embodiment, the plurality of electrodes are arranged as an array. The control unit is configured to use the plurality of frequency filter units to cause the array of electrodes to sequentially output respective ESF effects with the respective drive signals to create an impression of flow along the array of electrodes.
In an embodiment, the interface device comprises the plurality of delay elements, wherein the plurality of delay elements are configured to control a timing by which each electrode of the plurality of electrodes will output an ESF effect by introducing different respective periods of delay of the first drive signal from an input of the respective delay element to an output of the respective delay element.
In an embodiment, the plurality of electrodes is arranged in an array in which the plurality of electrodes has uniform spacing between adjacent electrodes.
In an embodiment, the array is a two-dimensional array.
In an embodiment, the interface device is a wearable device.
In an embodiment, the signal generating circuit comprises an amplifier circuit configured to amplify a first signal to the first drive signal, wherein the amplifier circuit is the only amplifier circuit in the interface device for amplifying the first signal to the first drive signal.
In an embodiment, the control unit is configured to select the subset of one or more electrodes from among a set of electrodes of the plurality of electrodes that are receiving user contact, such that some electrodes receiving user contact are not selected to generate a respective static ESF effect with the first drive signal.
One aspect of the embodiments herein relates to an interface device configured to provide an electrostatic friction (ESF) effect. The interface device comprises a signal generating circuit, a plurality of delay elements, and a plurality of electrodes. The signal generating circuit is configured to generate a first drive signal at an output of the signal generating circuit. The plurality of delay elements are configured to introduce respective periods of delay to the first drive signal from an input of the respective delay element to an output of the respective delay element. The plurality of electrodes correspond to the plurality of delay elements, wherein each of the plurality of electrodes is connected to an output of a respective delay element and is configured to generate a respective ESF effect with the first drive signal. The plurality of delay elements and their respective electrodes form a plurality of respective pairs that each includes a respective delay element and a respective electrode. The plurality of pairs of delay elements and their respective electrodes are electrically connected in series such that an input of a delay element of a first pair in the series is connected to an output of the signal generating circuit, and an input of a delay element of all other pairs in the series is electrically connected to an electrode of a previous pair in the series.
In an embodiment, the respective periods of delay introduced by the plurality of delay elements are the same.
In an embodiment, the respective periods of delay introduced by the plurality of delay elements are all different. Features, objects, and advantages of embodiments hereof will become apparent to those skilled in the art by reading the following detailed description where references will be made to the appended figures.
The foregoing and other features and advantages of the invention will be apparent from the following description of embodiments hereof as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. The drawings are not to scale.
The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.
Embodiments hereof relate to implementing a haptic enabled interface device (e.g., a handheld or otherwise graspable device such as a mobile device or game console controller, a wearable device, a laptop) which includes a plurality of electrodes for producing (e.g., generating) electrostatic friction (ESF) effects, and is configured to control which subset of one or more electrodes will generate one or more respective ESF effects with a drive signal, and/or is configured to vary how different electrodes generate respective ESF effects with the drive signal. For example, the haptic enabled interface device may include frequency filter units or relay switches which are configured to block the drive signal from reaching certain electrodes, or include shielding elements which are configured to electrically shield those electrodes from a surface of the device, so that those electrodes do not generate any ESF effect with the drive signal at the surface. In another example, the haptic enabled interface device may be configured to pass a drive signal to multiple electrodes, but may attenuate or delay the drive signal by different amounts/periods for different electrodes, so that the different electrodes generate respective ESF effects with the drive signal in different manners. The frequency filter units, delay elements, and relay switches may be different types of gating elements.
In an embodiment, the haptic enabled interface device may be configured to control which electrodes output respective ESF effects with a drive signal and/or how those electrodes output the ESF effects with the drive signal in order to convey a spatial relationship, a temporal relationship, a spatio-temporal relationship (e.g., a combination of a spatial relationship and a temporal relationship), and/or other information to a user. In an embodiment, the plurality of electrodes may sequentially output respective ESF effects to create an impression of flow along the electrodes. For instance, if the electrodes are arranged in a one-dimensional array (e.g., a line) or a two-dimensional array, the sequential output of the respective ESF effects along the array may create an impression of flow along the array. This impression of flow may be used to provide navigation instructions for a user, indicate progress of an operation, a passage of time, or for any other purpose.
In an embodiment, the plurality of electrodes may be used to produce (e.g., generate) static ESF effects. As discussed in more detail below, dynamic ESF effects may require a user to move a part of his or her body (e.g., finger tip) across an electrode, while static ESF effects allow the user's body (e.g., finger tip) to remain stationary. In some cases, static ESF effects may use a much higher voltage (e.g., 1.5 kV) than that used with dynamic ESF effects (e.g., 10 V). Thus, in some instances, a signal generating circuit of the haptic enabled device may use one or more amplifier circuits that include high-voltage electronics to generate a high-voltage drive signal for static ESF. For example, the drive signal may be an amplified signal with an amplitude (e.g., >1 kV) suitable for static ESF effects. In an embodiment, the haptic enabled interface device may include multiple amplifier circuits, with one amplifier circuit assigned to each electrode, so that the output of ESF effects can be separately controlled at each individual electrode. In another embodiment, the haptic enabled interface device may include only one amplifier circuit for generating any drive signal. The sole amplifier circuit may be included in the signal generating circuit. In this embodiment, the amplifier circuit outputs a drive signal that can be shared among the plurality of electrodes, which may produce respective ESF effects using the same drive signal. For instance, a plurality of individually controllable gating elements (e.g., switches, frequency filter units, or delay elements) may be placed between the single amplifier circuit and the respective electrodes to control ESF effects at those electrodes, or a plurality of shielding elements may be placed between the respective electrodes and a ground potential to control ESF effects at those electrodes. The gating elements or shielding elements may, e.g., cause only a subset of one or more electrodes of a plurality of electrodes to output respective one or more ESF effects with a first drive signal, or may cause at least two electrodes of the plurality of electrodes to output respective ESF effects with the first drive signal, but to do so in different manners. In another instance, a plurality of delay elements may be arranged in a series configuration to form a chain of delay elements, with each delay element gating a respective electrode. This series arrangement may cause a drive signal to sequentially propagate through the chain of delay elements and their respective electrodes to create the impression of flow, for instance.
The electrodes used to produce ESF effects (which may be referred to as ESF electrodes) may have a variety of sizes and shapes, such as squares, dots, and strips. For instance,
As discussed above, the electrodes 103a-103h or the electrodes 203a-203e may be used to create spatial and/or temporal feedback, such as to create an impression of flow of ESF effects along the electrodes, or to convey a spatial direction for a user to follow. With respect to
In another example, the electrodes 103a-103h or the electrodes 203a-203e may be used to indicate a spatial orientation of the corresponding haptic enabled interface device (and of a user wearing the device) relative to a location of interest. For example, electrode 103d or 103e may be designated as a center electrode that represents a current location of the device, while electrode 103b may be determined to fall on a left side of the center electrode when the strap 101 is worn, and electrode 103g may be determined to fall on a right side of the center electrode when strap 101 is worn. When a desired destination or object is to the left of the device's current location, a drive signal may be directed to the electrode 103b to output an ESF effect. When the desired destination or object is to the right of the device's current location, the drive signal may be directed to the electrode 103g to output an ESF effect.
In another example, the electrodes 103a-103h may be used to convey a temporal relationship between a current time and an event of interest. For example, each of the electrodes 103a-103h may correspond to different amounts of time (e.g., 15 minutes, 30 minutes, etc.) before a meeting, and may be selectively activated to indicate a current duration of time before a meeting. In yet another example, the electrodes 103a-103h may be used to indicate progress of an operation, such as a data transfer operation. For instance, electrodes 103a-103h may correspond to different percentages (e.g., 0%, 10%, 20%, etc.), and may be selectively activated to indicate what percentage of the data transfer operation is currently complete.
The electrodes 103a-103h, 203a-203e, 303a-303h, 403a-403f may be configured to generate an ESF effect, and may be referred to as ESF electrodes. In an embodiment, each electrode may be a conductive (e.g., metal) pad. In an embodiment, the plurality of electrodes 103a-103h, 203a-203e, 303a-303h, 403a-403f may be exposed electrodes and/or insulated electrodes. Some haptic enabled interface devices may include only exposed ESF electrodes, include only insulated ESF electrodes, or include a mixture of exposed ESF electrodes and insulated ESF electrodes. An exposed electrode may be disposed at a respective portion of a surface of an interface device (e.g., surface 101b), and more specifically may form the respective portion of the surface. The exposed electrode may, e.g., be configured to be directly electrically coupled to a user upon the user making contact with the exposed electrode (or disposed over the exposed electrode with only a very small air gap therebetween) at the respective portion of the surface. The contact may refer to contact with, e.g., the user's skin. More generally speaking, the contact may refer to contact in which a drive signal can create an electrostatic friction effect on the user's body. In one example, an exposed electrode may be a conductive pad adhered on top of a body of the interface device (e.g., on top of a body of band 101). In one example, the exposed electrode may be a conductive pad exposed through an opening in a body, a housing or other structural element of the interface device (e.g., through an opening in a casing of a mobile phone).
In an embodiment, an insulated electrode may be disposed at a respective portion of an outer surface (e.g., surface 101b) of an interface device, and more specifically may be disposed behind the respective portion of the outer surface. The insulated electrode may, e.g., be separated from the surface by a thin insulating layer, such as a layer of dielectric material. The insulated layer may be configured to be capacitively electrically coupled to a user upon the user making contact with the insulated electrode's respective portion of the surface. In one example, an insulated electrode may be embedded within a plastic outer cover of a mobile phone or game console controller, or embedded within a band of a smart watch, such that there is an electrically insulating material (e.g., a dielectric material) between the electrode and the outer surface of the mobile phone, game console controller, or smart watch. In another example, the insulated electrodes may be a conductive material placed on a body of the smart phone, smart watch, or game console controller, and may have then been covered with an insulating material (e.g., a layer of Kapton® tape).
In an embodiment, the multiple electrodes may be used, e.g., to generate a static ESF effect or a dynamic ESF effect. Dynamic ESF effects may involve exerting electrostatic forces on a finger or other part of the user's body while the finger or other part of the user's body is moving on a surface of the interface device. The electrostatic forces may be created by applying a time-varying signal to an electrode. The electrostatic forces may attract the finger, and may be perceived as friction during the movement of the finger. Static ESF effects may be generated while the user's finger or other body part remains stationary relative to and contacting a surface of the interface device. Static ESF effects may also involve applying a time-varying signal to an electrode to create electrostatic forces. In some cases, static ESF may involve a higher voltage level for the time-varying signal compared to that for dynamic ESF.
In an embodiment, the handheld interface device 100 includes electrodes which are signal electrodes or switchable to being signal electrodes, and includes electrodes which are ground electrodes or switchable to being ground electrodes. For example,
Returning to
In an embodiment, the signal generating circuit 104 may output a first drive signal and a second drive signal which correspond to separate time periods, or separate signal generating commands. For example, a voltage waveform that is output by the signal generating circuit 104 in a first time period (e.g., first 1-second window) may be considered a first drive signal, while a voltage waveform that is output by the signal generating circuit 104 in a second time period (e.g., a subsequent 1-second window) may be considered a second drive signal. In another example, a voltage waveform that is output by the signal generating circuit 104 in response to a first signal generating command from a software application (e.g., device driver) or application programming interface (API) controlling control unit 110 may be considered a first drive signal, while a voltage waveform that is output by the signal generating circuit 104 in response to a second signal generating command may be considered a second drive signal. In an embodiment, a first electrode that receives a drive signal may be considered to be generating a first ESF effect, while a second electrode that receives the same drive signal may be considered to be producing a second ESF effect. The two electrodes may receive the same version of the drive signal (e.g., same intensity, same phase, and same frequency components) or different versions (e.g., different intensities, different phases, or different frequency components) of the same drive signal.
In an embodiment, a plurality of gating elements 105b-105g may be disposed between respective electrodes 103b-103g and an output of the signal generating circuit 104, to control which of the electrodes 103b-103g will be signal electrodes. Examples of a gating element include a frequency filter, a delay element, and a switch (e.g., a high-voltage relay switch or high-voltage transistor). The plurality of gating elements 105b-105g may be configured to control which electrode(s) of the electrodes 103b-103g will receive a drive signal from the output of the signal generating circuit 104, and/or control a manner in which the drive signal reaches an electrode, such as an attenuation level or period of delay (e.g., from a phase shift) of the drive signal in reaching the electrode. In an embodiment, the relay switches or high-voltage transistors may form a high-voltage multiplexer that electrically connect a drive signal to exactly one electrode of electrodes 103b-103g, which may be selected under software control.
In
In an embodiment, the control unit 110 is configured to select a subset of one or more electrodes from the set of electrodes 103a-103h, or from the set of electrodes 103b-103g that are switchable to being signal electrodes, for outputting an ESF effect with a drive signal. The control unit may be configured to select a subset of one or more electrodes (e.g., 103b) from among a set of electrodes (e.g., 103b, 103c, 103d) that are receiving user contact, such that the electrodes receiving user contact are not selected to produce a respective static ESF effect with a drive signal.
In an embodiment, a frequency filter unit may be configured to attenuate a frequency component of a signal that falls within a pass-through band of the frequency filter unit. For a drive signal that is a weighted sum of a 50 Hz sinusoidal signal and a 100 Hz sinusoidal signal, for example, the frequency filter unit 1105b may attenuate the 50 Hz sinusoidal signal by 50% (while completely blocking the 100 Hz component of the drive signal), and the frequency filter unit 1105c may attenuate the 100 Hz sinusoidal signal by 25% (while completely blocking the 50 Hz component of the drive signal). In an embodiment, each of the frequency filter units may be configured to introduce a phase shift into a frequency component of a signal that falls within a pass-through band of the frequency filter unit. The phase shift may introduce a delay by which the drive signal reaches a respective electrode connected to the frequency filter unit.
In an embodiment, the frequency filter units of a haptic enabled interface device may have pass-through bands with the same bandwidth, or with different respective bandwidths. In an embodiment, a bandwidth for each pass-through band may be nonzero (e.g., 20 Hz). In an embodiment, a bandwidth for a pass-through band may be small enough such that the pass-through band may be treated as a pass-through frequency (e.g., a pass-through frequency of 50 Hz, 100 Hz, or 200 Hz). The pass-through frequency may be associated with a digital frequency filter unit that performs digital signal processing (e.g., a Fourier transform) to perform filtering.
In the embodiment of
In an embodiment, control unit 110 may be configured to use the frequency filter units 2105b, 2105c, and 2105d to cause only a subset of one or more electrodes of the set of electrodes 103b, 103c, and 103d to output one or more respective ESF effects with a first drive signal. For instance, the control unit may generate the first drive signal with only a frequency component of 200 Hz. In that instance, only electrodes 103b and 103d will output respective ESF effects with the first drive signal. In an embodiment, the control unit may be configured to cause at least two electrodes of electrodes 103b, 103c, and 103d to output respective ESF effects with the first drive signal, but to do so in different manners. For instance, the first drive signal with the 200 Hz frequency component may be attenuated by 70% by frequency filter unit 2105b, and may be attenuated by 50% by frequency filter unit 2105d. Thus, the two respective electrodes 103b and 103d may receive the first drive signal with different levels of attenuation, and thus output respective ESF effects with the first drive signal in different manners. In another example, the first drive signal may include frequency components of only 100 Hz and 200 Hz. As shown in
While
As shown in
In an embodiment, each of the delay elements in
In an embodiment, each of the delay elements in
As discussed above, generating an ESF effect may involve a signal electrode and a ground electrode. An insulated electrode may be usable as a signal electrode at one point in time by being electrically connected to an output of a signal generating circuit, and as a ground electrode at another point in time by being electrically connected to a ground potential.
In an embodiment depicted in
In an embodiment, each shielding element of the shielding elements 113a-113h is switchably connectable to ground, via a respective gating element (e.g., switch) of the gating elements 115a-115h, which may be controlled by the control unit 110. In this embodiment, each of the electrodes 103a-103h may be electrically connected to an output of a signal generating circuit 104. Each of the electrodes 103a-103h may generate an electric field based on the drive signal. A shielding element (e.g., 113b) of the shielding elements 113a-113h may suppress the electric field emanating from a respective electrode (e.g., 103b) by being switchably connected to ground, such as via a respective gating element (e.g., 115b) of the gating elements 115a-115h. When the shielding element is electrically connected to ground, it may block the electric field of a respective electrode from reaching an outer surface of the interface device. Thus, this shielding element may prevent the corresponding electrode (e.g., 103b) from generating an ESF effect with the drive signal. Another electrode (e.g., 103c) may be allowed to generate an ESF effect with the drive signal by having its respective shielding element (e.g., 113c) electrically disconnected from ground. Shielding elements are discussed in more detail in U.S. application Ser. No. 15/239,464 (Atty Dkt. No. IMM627), filed on Aug. 17, 2016, the content of which is incorporated by reference herein in its entirety.
In an embodiment, the sense of flow may be created with one drive signal, or with multiple drive signals. For example, the sense of flow may be created with one drive signal and the multiple delay elements shown in
In another example, the sense of flow may be created with multiple drive signals and the frequency filter units or relay switches shown in
In an embodiment, creating or producing a sense of flow may be used to convey a temporal relationship between a current time and an event of interest (e.g., a temporal relationship between a current time and a meeting), as discussed above. In an embodiment, creating or producing a sense of flow may be used to convey information such as the status of an operation.
In an embodiment, the gating elements discussed above may be used to create particular ESF effects by implementing a sequence of at least a first electrode, a second electrode, and a third electrode, in which the second electrode is a middle electrode, and the first and third electrodes are immediately next to the middle electrode and on opposite sides of the middle electrode. For instance, in order to generate a particular ESF effect, the gating elements may allow a drive signal to reach the first electrode and the second electrode, but not the third electrode.
As discussed above, the array of static ESF electrodes may have a variety of shapes and arrangements, such as long strips (e.g., disposed over the length of a bracelet), small dots (e.g., all over the surface of a phone), or a 2D array of large squares (e.g., on the back of a tablet computer). In an embodiment, long strips and larger pads may provide better static ESF effects than smaller electrodes, because they are less likely to be completely covered by a user's skin.
Embodiments herein may be used for a mobile phone, gaming, automotive, augmented reality (AR), virtual reality (VR), or wearables application. For example, the handheld interface device may be a controller for a VR or AR application. In an embodiment, the electrodes may be used to expand the expressivity of static ESF feedback by producing a variety of spatial and/or temporal effects.
Embodiments herein may be used for dynamic ESF effects or static ESF effects. For static ESF effects, the drive signal applied to the selected subset of the plurality of electrodes may have an amplitude of at least 1 kV.
While various embodiments have been described above, it should be understood that they have been presented only as illustrations and examples of the present invention, and not by way of limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents. It will also be understood that each feature of each embodiment discussed herein, and of each reference cited herein, can be used in combination with the features of any other embodiment. All patents and publications discussed herein are incorporated by reference herein in their entirety.
Claims
1-18. (canceled)
19. An interface device configured to provide an electrostatic friction (ESF) effect, the interface device comprising:
- a signal generating circuit configured to generate a first drive signal at an output of the signal generating circuit;
- a first electrode disposed at a surface of the interface device and permanently electrically connected to a source of ground potential;
- a second set of electrodes disposed at the surface of the interface device, wherein the first electrode is not part of the second set of electrodes;
- a plurality of gating elements, wherein each gating element of the plurality of gating elements comprises at least one switch and is configured to switch between (a) electronically connecting a respective electrode of the second set of electrodes to the output of the signal generating circuit and (b) electrically connecting the respective electrode to the source of ground potential or leaving the respective electrode in an electrically floating state;
- a control circuit configured to select one or more electrodes of the second set of electrodes to output the ESF effect with the first drive signal, to control the plurality of gating elements to electrically connect the one or more electrodes that have been selected to the output of the signal generating circuit, and to control the plurality of gating elements to either: electrically connect all unselected electrodes of the second set of electrodes to the source of ground potential, or leave all unselected electrodes of the second set of electrodes in the electrically floating state.
20. The interface device of claim 19, wherein the signal generating circuit comprises a signal processor and an amplifier, wherein the signal processor is configured to generate an initial drive signal, and the amplifier is configured to amplify the initial drive signal to generate the first drive signal, and wherein each gating element of the plurality of gating elements is electrically connected to an output of the amplifier.
21. The interface device of claim 20, wherein the amplifier is configured to generate the first drive signal with an amplitude of at least 1 kV.
22. The interface device of claim 21, wherein the signal generating circuit is configured to generate the first drive signal as a pulse with the amplitude of at least 1 kV.
23. The interface device of claim 21, wherein the amplifier is the only amplifier of the signal generating circuit for amplifying any signal from the signal processor.
24. The interface device of claim 23, wherein each electrode of the second set of electrodes is an insulated electrode.
25. The interface device of claim 24, wherein the first electrode is an exposed electrode.
26. The interface device of claim 20, wherein the at least one switch of a respective gating element of the plurality of gating elements is a relay switch or a transistor.
27. The interface device of claim 19, wherein the control circuit is configured
- to select only one electrode of the second set of electrodes to generate the ESF effect with the first drive signal,
- to control the plurality of gating elements to electrically connect only the one electrode that is selected to the output of the signal generating circuit, and
- to control the plurality of gating elements to electrically connect all unselected electrodes of the second set of electrodes to the source of ground potential.
28. The interface device of claim 19, wherein the interface device is a wearable device having a band, wherein the surface of the interface device includes a surface of the band, and wherein the plurality of electrodes are disposed at the surface of the band.
29. The interface device of claim 28, wherein each electrode of the second set of electrodes is shaped as a strip.
30. The interface device of claim 19, wherein the second set of electrodes are arranged as a two-dimensional array.
31. The interface device of claim 19, wherein the control circuit is configured to determine a spatial relationship between a location of an object or event and a location of the interface device,
- wherein the control circuit is configured to select the one or more electrodes of the second set of electrodes based on the spatial relationship between the location of the object or event and the location of the interface device.
32. The interface device of claim 19, wherein the control circuit is configured to determine a temporal relationship between a time of an event and a current time,
- wherein the control circuit is configured to select the one or more electrodes of the second set of electrodes based on the temporal relationship between the time of the event and the current time.
33. The interface device of claim 19, wherein each gating element of the plurality of gating elements comprises a first switch and a second switch, wherein the first switch is configured to switch between electrically connecting a respective electrode of the second set of electrodes to the output of the signal generating circuit and leaving the respective electrode in the electrically floating state, and wherein the second switch is configured to switch between electrically connecting the respective electrode to the source of ground potential and leaving the respective electrode in the electrically floating state.
34. The interface device of claim 19, wherein the control circuit is configured to select the one or more electrodes from among a subset of the second set of electrodes, the subset of electrodes receiving user contact, such that some electrodes of the second set of electrodes receiving user contact are not selected to generate a respective ESF effect with the first drive signal.
35. The interface device of claim 19, wherein the interface device is a mobile device, and the second set of electrodes are disposed on a back surface of the mobile device.
36. The interface device of claim 35, wherein each electrode of the second set of electrodes is shaped as a circle or as a square.
Type: Application
Filed: Mar 29, 2019
Publication Date: Jul 25, 2019
Inventors: Vincent LEVESQUE (Montreal), Juan Manuel CRUZ HERNANDEZ (Montreal), Mohammadreza MOTAMEDI (Montreal), Kaniyalal SHAH (Fremont, CA), Ali MODARRES (San Jose, CA)
Application Number: 16/369,074