Distributed air-filled touch sensing

Abstract

A distributed air-filled touch sensing system is provided. The distributed air-filled touch sensing system includes a sensing bladder array having a plurality of bladders, channels, and ports in fluid communication. The system also includes a pressure regulator in fluid communication with one of the plurality of ports for regulating pressure in the sensing bladder array. The system also includes a plurality of sensors, each of the plurality of sensors in fluid communication with one of the plurality of ports for measuring pressure in the sensing bladder array. The system also includes a processor in communication with the plurality of sensors. The processor is configured to determine which of the plurality of bladders has been pressed by a user.

Description

Technical Field

[0001] This disclosure relates to human-machine interfaces, and more specifically, to distributed inflatable touch sensing systems for reducing the complexity of sensing electronics, enabling the variability of interface features when not in use, and facilitating manufacture. Background Technology

[0002] Human-Machine Interfaces (HMIs) allow users to interact with machines to control their operation. HMIs have been developed to allow users to interact with a wide variety of machines, including, for example, computers, smartphones, vehicles, and industrial machines. Examples of HMIs can include touchscreens, electrical switches and buttons, knobs, capacitive sensors, keyboards, computer mice, and so on. HMIs are typically sensitive to environmental conditions such as dust, moisture, or electrical noise. Furthermore, HMIs can occupy significant space within or on the machines they control. For example, HMI systems such as touchscreens, buttons, and knobs can occupy a large portion of a car's dashboard or center console. Additionally, some types of HMIs (e.g., touchscreens) may not provide tactile feedback to the user during use. While some types of HMIs (e.g., electrical switches and buttons) can provide policy feedback to the user upon interaction, the nature and intensity of this feedback are determined by the HMI's mechanical design and therefore cannot be adjusted based on, for example, the environment in which the user interacts during use.

[0003] Therefore, although current human-machine interfaces have achieved their intended purpose, there is still a need for new and improved systems and methods that allow users to interact with machines. Summary of the Invention

[0004] According to several aspects, a distributed inflatable touch sensing system is provided. The distributed inflatable touch sensing system includes a sensing airbag array having a first thermoplastic sheet having an inner surface and an outer surface, the inner surface having a sealed portion and a plurality of unsealed portions. The sensing airbag array also includes a second thermoplastic sheet having an inner surface and an outer surface. The inner surface includes a sealed portion and a plurality of unsealed portions. Furthermore, the sealed portion of the inner surface of the first thermoplastic sheet is fixedly attached to the sealed portion of the inner surface of the second thermoplastic sheet. A first of the plurality of unsealed portions of the inner surface of the first thermoplastic sheet and a first of the plurality of unsealed portions of the inner surface of the second thermoplastic sheet form a plurality of airbags. A second of the plurality of unsealed portions of the inner surface of the first thermoplastic sheet and a second of the plurality of unsealed portions of the inner surface of the second thermoplastic sheet form a plurality of channels, each of the plurality of channels having a volume. The plurality of channels are in fluid communication with the plurality of airbags. A third of a plurality of unsealed portions on the inner surface of a first thermoplastic sheet and a third of a plurality of unsealed portions on the inner surface of a second thermoplastic sheet form a plurality of ports. The plurality of ports are in fluid communication with a plurality of airbags. The distributed inflatable touch sensing system also includes a pressure regulator for regulating the pressure in the array of sensing airbags. The pressure regulator is in fluid communication with at least one of the plurality of ports. The distributed inflatable touch sensing system also includes a plurality of sensors for measuring the pressure in the array of sensing airbags, each of the plurality of sensors being in fluid communication with at least one of the plurality of ports. The distributed inflatable touch sensing system also includes a processor communicating with the plurality of sensors, the processor being configured to receive a plurality of pressure measurements from the plurality of sensors. The processor is also configured to determine which of the plurality of airbags has been pressed by a user.

[0005] In other aspects of this disclosure, the first thermoplastic sheet and the second thermoplastic sheet are made of a material selected from polyethylene, thermoplastic polyurethane and polypropylene.

[0006] In another aspect of this disclosure, the sealing portions of the inner surfaces of the first and second thermoplastic sheets are fixedly attached using heat sealing.

[0007] In another aspect of this disclosure, the processor is programmed to receive multiple pressure measurements from each of a plurality of sensors over a fixed time period. The processor is also programmed to determine, for each of the plurality of sensors, the time at which each of the plurality of sensors measures maximum pressure. The processor is further programmed to calculate, using a predetermined algorithm, which of the plurality of airbags has been pressed by the user. The predetermined algorithm is based at least in part on the time at which each of the plurality of sensors measures maximum pressure.

[0008] In another aspect of this disclosure, the predetermined algorithm further includes calculating the difference between the time when the first of the plurality of sensors measures the maximum pressure and the time when the second of the plurality of sensors measures the maximum pressure.

[0009] In another aspect of this disclosure, the calculated difference between the time when the first of the plurality of sensors measures the maximum pressure and the time when the second of the plurality of sensors measures the maximum pressure depends at least in part on the volume of each of the plurality of channels.

[0010] In another aspect of this disclosure, multiple airbags and multiple channels are arranged to form a one-dimensional array, and multiple sensors are three sensors.

[0011] In another aspect of this disclosure, the predetermined algorithm also includes calculating the identifier value using the following formula:

[0012]

[0013] x defines the identifier value, t1 defines the time when the first of the multiple sensors measures the maximum pressure, t2 defines the time when the second of the multiple sensors measures the maximum pressure, and t3 defines the time when the third of the multiple sensors measures the maximum pressure.

[0014] In another aspect of this disclosure, the pre-calculation algorithm further includes comparing an identifier value with a set of predetermined ranges corresponding to each of the plurality of airbags. The pre-calculation algorithm also includes determining which of the plurality of airbags has been pressed by the user. When the identifier value falls within a predetermined range corresponding to one of the plurality of airbags in the set of predetermined ranges, it is determined that one of the plurality of airbags has been pressed by the user.

[0015] In another aspect of this disclosure, at least one of the channels includes a constraint. This constraint is at least one of porous material, bending, and reduction in cross-sectional area. The calculated difference depends at least in part on the constraint in the channel.

[0016] According to several aspects, a method for manufacturing a distributed inflatable touch-sensing airbag array is provided. The method includes cutting a mask into a shape defining a plurality of airbag portions, channel portions, and port portions. The method further includes disposing a porous material on each of the plurality of channel portions of the mask, and attaching the mask with the porous material disposed thereon to an inner surface of a first thermoplastic sheet. The method further includes removing the plurality of channel portions of the mask such that the porous material remains between each of the plurality of airbag portions. The method further includes placing a second thermoplastic sheet on the first thermoplastic sheet. Portions of the inner surfaces of the first and second thermoplastic sheets that contact the mask or the porous material are defined as masked portions. Portions of the inner surfaces of the first and second thermoplastic sheets that do not contact the mask or the porous material are defined as unmasked portions. The method further includes fusing the unmasked portions of the inner surface of the second thermoplastic sheet to the unmasked portions of the inner surface of the first thermoplastic sheet to form a heat seal, thereby forming an airtight volume between the masked portions of the inner surfaces of the first and second thermoplastic sheets.

[0017] In another aspect of this disclosure, the cutting step further includes cutting the mask into shapes that define a plurality of airbag portions, channel portions, and port portions. The plurality of airbag portions and the plurality of channel portions are arranged in a one-dimensional array.

[0018] In another aspect of this disclosure, the first thermoplastic sheet and the second thermoplastic sheet are selected from a first polyethylene sheet and a second polyethylene sheet, a first thermoplastic polyurethane sheet and a second thermoplastic polyurethane sheet, and a first polypropylene sheet and a second polypropylene sheet.

[0019] In another aspect of this disclosure, the mask is made of cellophane.

[0020] In another aspect of this disclosure, the porous material is selected from porous polyester yarn, porous nylon yarn, and porous cotton yarn.

[0021] In another aspect of this disclosure, the method further includes attaching a first fabric layer to the outer surface of a first thermoplastic sheet and attaching a second fabric layer to the outer surface of a second thermoplastic sheet.

[0022] According to several aspects, a distributed inflatable touch sensing system is provided. The distributed inflatable touch sensing system includes a sensing airbag array having a first thermoplastic sheet having an inner surface and an outer surface, the inner surface having a sealed portion and a plurality of unsealed portions. The sensing airbag array also includes a second thermoplastic sheet having an inner surface and an outer surface. The inner surface includes a sealed portion and a plurality of unsealed portions, wherein the sealed portion of the inner surface of the first thermoplastic sheet is fixedly attached to the sealed portion of the inner surface of the second thermoplastic sheet. A first of the plurality of unsealed portions of the inner surface of the first thermoplastic sheet and a first of the plurality of unsealed portions of the inner surface of the second thermoplastic sheet form a plurality of airbags. A second of the plurality of unsealed portions of the inner surface of the first thermoplastic sheet and a second of the plurality of unsealed portions of the inner surface of the second thermoplastic sheet form a plurality of channels, each of the plurality of channels having a volume. The plurality of channels are in fluid communication with the plurality of airbags. A third of a plurality of unsealed portions on the inner surface of a first thermoplastic sheet and a third of a plurality of unsealed portions on the inner surface of a second thermoplastic sheet form a plurality of ports. The plurality of ports are in fluid communication with a plurality of airbags. The sensing airbag array also includes porous material disposed in each of the plurality of channels. The distributed inflatable touch sensing system also includes a pressure regulator for regulating the pressure in the sensing airbag array. The pressure regulator is in fluid communication with at least one of the plurality of ports. The distributed inflatable touch sensing system also includes a plurality of sensors for measuring the pressure in the sensing airbag array, each of the plurality of sensors being in fluid communication with at least one of the plurality of ports. The distributed inflatable touch sensing system also includes a processor communicating with the plurality of sensors, the processor being configured to receive pressure measurements from the plurality of sensors. The processor is programmed to receive a plurality of pressure measurements from each of the plurality of sensors over a fixed time period and to determine the time when each of the plurality of sensors measures maximum pressure. The processor is also programmed to determine, at least in part, which of the plurality of airbags has been pressed by the user based on the time when each of the plurality of sensors measures maximum pressure.

[0023] In another aspect of this disclosure, multiple airbags and multiple channels are arranged in a one-dimensional array, and multiple sensors are three sensors.

[0024] In another aspect of this disclosure, the multiple airbags and multiple channels are also arranged in a circular pattern.

[0025] In another aspect of this disclosure, multiple airbags and multiple channels are arranged in a two-dimensional array, and multiple sensors are four sensors.

[0026] Further areas of application will become apparent from the description provided herein. It should be understood that the descriptions and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0027] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of this disclosure in any way.

[0028] Figure 1 This is a system diagram of a distributed inflatable touch sensing system according to an exemplary embodiment.

[0029] Figure 2 This is an exploded view of the sensing airbag array according to an exemplary embodiment.

[0030] Figure 3 It is a graph showing the change of pressure measurement values ​​over time after the airbag is pressed, according to an exemplary embodiment.

[0031] Figure 4 It is a graph of a predetermined range of identifier values ​​for a given airbag, according to an exemplary embodiment, the predetermined range being used to determine which airbag has been compressed.

[0032] Figure 5a This is a perspective view of a one-dimensional sensing airbag array configured for use with three sensors, according to an exemplary embodiment.

[0033] Figure 5b This is a cross-sectional view of a portion of a sensing airbag array according to an exemplary embodiment, wherein one channel contains a constraint in the form of a porous material, and the cross-sectional area of ​​one channel is reduced.

[0034] Figure 5c This is a perspective view of a one-dimensional sensing airbag array configured for use with three sensors, according to an exemplary embodiment, wherein the channel contains a constraint in a curved form within the channel.

[0035] Figure 5d This is a perspective view of a one-dimensional sensing airbag array configured for use with three sensors according to an exemplary embodiment, wherein the airbags and channels are arranged in a circular arrangement.

[0036] Figure 5e This is a perspective view of a one-dimensional sensing airbag array configured for use with three sensors, according to an exemplary embodiment, wherein the airbags and channels are arranged in a pseudo-two-dimensional grid arrangement.

[0037] Figure 5f It is a perspective view of a two-dimensional sensing airbag array configured for use with four sensors according to an exemplary embodiment, wherein the airbags and channels are arranged in a two-dimensional grid arrangement. Detailed Implementation

[0038] The following description is merely exemplary in nature and is not intended to limit this disclosure, application, or use.

[0039] refer to Figure 1 A distributed inflatable touch sensing system 30 is illustrated. System 30 includes a sensing airbag array 32, a pressure regulator 34, a plurality of sensors 36, and a processor 38. The sensing airbag array 32 includes a plurality of airbags 40, a plurality of channels 42, and a plurality of ports 44. The plurality of airbags 40 are in fluid communication with each of the plurality of channels 42. The airbags 40 provide an interface through which a user can interact with the distributed inflatable touch sensing system 30. System 30 is configured to determine which of the plurality of airbags 40 the user is interacting with. Each of the plurality of ports 44 formed in the sensing airbag array 32 provides fluid communication with each of the pressure regulator 34 and the plurality of sensors 36.

[0040] The pressure regulator 34 is in fluid communication with one of the ports 44 of the sensing airbag array 32. The pressure regulator 34 allows the sensing airbag array 32 to be pressurized to a predetermined pressure using a fluid. For example, the fluid could be air, and the predetermined pressure could be 3 pounds per square inch (PSI). By adjusting the pressure in the sensing airbag array 32 using the pressure regulator 34, the stiffness of the airbag 40 can be controlled, thereby providing adjustable tactile feedback to the user when interacting with the airbag 40. The pressure regulator 34 can also be used to release pressure from the sensing airbag array 32, allowing the airbag 40 and channels 42 to deflate when the distributed inflatable touch sensing system 30 is not in use.

[0041] Multiple sensors 36 are in fluid communication with one of multiple ports 44 of the sensing airbag array 32. The multiple sensors 36 are pressure measurement sensors configured to measure the pressure in the sensing airbag array 32.

[0042] Processor 38 communicates with multiple sensors 36. Processor 38 is programmed to receive multiple pressure measurements from the sensors 36 and determine which of the multiple airbags 40 has been interacted with or pressed by the user. Processor 38 can be configured to transmit information about which airbag 40 has been pressed. Processor 38 can also be configured to activate or otherwise influence the operation of another system, such as a heating, ventilation, and air conditioning (HVAC) system in a vehicle (not shown), based on the determination that which airbag 40 has been pressed by the user.

[0043] refer to Figure 2An exploded view of a sensing airbag array 32 according to an exemplary embodiment is shown. The array 32 is formed from two thermoplastic sheets 46 and 60. The first thermoplastic sheet 46 has an outer surface 48 and an inner surface 50. The inner surface 50 includes a sealing portion 52 and a plurality of unsealed portions 54, 56, and 58. A first unsealed portion 54 of the plurality of unsealed portions defines one half of a plurality of airbags 40. A second unsealed portion 56 of the plurality of unsealed portions defines one half of a plurality of channels 42. A third unsealed portion 58 of the plurality of unsealed portions defines one half of a plurality of ports 44.

[0044] The second thermoplastic sheet 60 has an outer surface 62 and an inner surface 64. The inner surface 64 includes a sealed portion 66 and a plurality of unsealed portions 68, 70, and 72. A first unsealed portion 68 of the plurality of unsealed portions defines one half of a plurality of air bladders 40. A second unsealed portion 70 of the plurality of unsealed portions defines one half of a plurality of channels 42. A third unsealed portion 72 of the plurality of unsealed portions defines one half of a plurality of ports 44. When the first thermoplastic sheet 46 is stacked on the second thermoplastic sheet 60, the plurality of unsealed portions 54, 56, and 58 on the inner surface 50 of the first thermoplastic sheet 46 are aligned with corresponding portions of the plurality of unsealed portions 68, 70, and 72 on the inner surface 64 of the second thermoplastic sheet 60.

[0045] A mask 74 is disposed between the first thermoplastic sheet 46 and the second thermoplastic sheet 60. The mask 74 may be made of cellophane, white paper, or another thin, non-melting material. The mask 74 may also be soluble, allowing it to dissolve and be removed from the sensing airbag array 32. The mask 74 includes a plurality of airbag portions 76, channel portions 78, and port portions 80. The plurality of airbag portions 76 of the mask 74 are aligned with corresponding unsealed portions 54 on the first thermoplastic sheet 46 and corresponding unsealed portions 68 on the second thermoplastic sheet 60. The plurality of channel portions 78 of the mask 74 are aligned with corresponding unsealed portions 56 on the first thermoplastic sheet 46 and corresponding unsealed portions 70 on the second thermoplastic sheet 60. The plurality of port portions 80 of the mask 74 are aligned with corresponding unsealed portions 58 on the first thermoplastic sheet 46 and corresponding unsealed portions 72 on the second thermoplastic sheet 60. Therefore, the mask 74 prevents the first thermoplastic sheet 46 from contacting the second thermoplastic sheet 60 at the non-sealed portions 54, 56, 58, 68, 70 and 72.

[0046] The sensing airbag array 32 may also include a first fabric layer 82 attached to the outer surface 48 of the first thermoplastic sheet 46 and a second fabric layer 84 attached to the outer surface 62 of the second thermoplastic sheet 60. The first fabric layer 82 and the second fabric layer 84 are decorative layers that can enhance the aesthetics of the sensing airbag array 32.

[0047] refer to Figure 3 A graph 86 provides multiple pressure measurements. The processor 38 is programmed to receive multiple pressure measurements from multiple sensors 36. The vertical axis 88 of graph 86 corresponds to the relative pressure measurements received by the processor 38. The horizontal axis 90 of graph 86 corresponds to a fixed time period during which the processor 38 receives the pressure measurements.

[0048] The first trace 92 shows the relative pressure of the first of the multiple pressure sensors 36 over a fixed time period. The second trace 94 shows the relative pressure of the second of the multiple pressure sensors 36 over a fixed time period. The third trace 96 shows the relative pressure of the third of the multiple pressure sensors 36 over a fixed time period.

[0049] Processor 38 is programmed to determine the time corresponding to the maximum relative pressure value of each of traces 92, 94, and 96. The maximum relative pressure value of trace 92 is indicated by reference numeral 98. The maximum relative pressure value of trace 94 is indicated by reference numeral 100. The maximum relative pressure value of trace 96 is indicated by reference numeral 102.

[0050] In addition to determining the time when the maximum relative pressure value occurs, the magnitude of the maximum relative pressure value can also be used to provide a magnitude sensing capability. To provide a magnitude sensing capability, the processor 38 can be programmed to compare the maximum relative pressure values ​​98, 100, and 102 with predetermined thresholds to determine the relative force with which the user presses the airbag 40.

[0051] After determining the maximum relative pressure values ​​98, 100, and 102 and the times at which they occur, the processor 38 is also programmed to calculate two time differences 104 and 106. The first time difference 104 is the difference between the time when a third of the plurality of pressure sensors 36 measures the maximum relative pressure value 102 and the time when a second of the plurality of pressure sensors 36 measures the maximum relative pressure value 100. The second time difference 106 is the difference between the time when a first of the plurality of pressure sensors 36 measures the maximum relative pressure value 98 and the time when a second of the plurality of pressure sensors 36 measures the maximum relative pressure value 100.

[0052] refer to Figure 4 A graph 108 is shown, illustrating identifier values ​​used to determine which airbag has been pressed by a user. The processor 38 is also programmed to use mathematical formulas to calculate the identifier values ​​and compare them to a predetermined range 114 to determine which of the plurality of airbags 40 has been pressed by the user. The vertical axis 110 of graph 108 corresponds to the calculated identifier values, and the horizontal axis 112 corresponds to the plurality of airbags 40, such as seven airbags. This disclosure envisions several mathematical formulas that can be used to calculate the identifier values. Examples of mathematical formulas that can be used include: Where t3-t2 is the first time difference of 104, t1-t2 is the second time difference of 106, and Y is the offset value, for example, Y = 0.5. This disclosure envisions that other mathematical formulas can be used to calculate the identifier value.

[0053] For example, chart 108 was generated using multiple trials involving multiple presses of each of the seven airbags 40. Mathematical formula. Used to calculate the identifier value shown in Figure 108.

[0054] To determine which of the multiple airbags 40 has been pressed by the user, a calculated identifier value is compared with a predetermined range 114 corresponding to each of the multiple airbags 40. If the identifier value is within the predetermined range 114 corresponding to one of the multiple airbags 40, it is determined that the one of the multiple airbags 40 has been pressed by the user.

[0055] Figure 5a , 5c Figures 5d and 5e depict one-dimensional sensing airbag arrays 116, 118, 120, and 122. One-dimensional means that the airbags 40 are fluidly connected in a linear manner via channels 42. Therefore, each airbag 40 is connected in series to the next airbag 40 via one of the multiple channels 42, with the last airbag 124 not connected to the first airbag 126. The one-dimensional sensing airbag arrays 116, 118, 120, and 122 require at least three sensors 36 to determine which airbag 40 has been pressed by the user.

[0056] refer to Figure 5a An example of a one-dimensional sensing airbag array 116 is shown. Figure 5a The illustrated one-dimensional sensing airbag array 116 includes seven airbags 40, four ports 44, and multiple channels 42 providing fluid communication between the airbags 40 and the ports 44. The one-dimensional sensing airbag array 116 is configured to be connected to three sensors 36 and a pressure regulator 34 via the four ports 44.

[0057] refer to Figure 5b The diagram illustrates a cross-sectional view of two airbags 40 and a channel 42 of an exemplary one-dimensional sensing airbag array 116. A constraint has been provided within the channel 42. This constraint may include a porous material 128, including, for example, polyester yarn, nylon yarn, cotton yarn, or porous foam material. The inclusion of porous material 128 in the channel 42 reduces the volume of the channel 42. The constraint within the channel 42 may also include a reduction in the cross-sectional area of ​​the channel 42, as indicated by reference numeral 129. Properties of the porous material 128, such as diameter and fiber characteristics, can be selected to influence the airflow in the channel 42. Properties of the reduced cross-sectional area portion 129 in the channel 42 can also be selected to influence the airflow in the channel 42. The constraints 128 and 129 in the channel 42 may affect a reference. Figure 3The calculated time differences of 10⁴ and 10⁶ are discussed, as well as the accuracy and precision of the distributed inflatable touch sensing system 30.

[0058] refer to Figure 5c A second example of a one-dimensional sensing airbag array 118 is shown. The one-dimensional sensing airbag array 118 includes seven airbags 40, four ports 44, and multiple channels 42. The one-dimensional sensing airbag array 118 is configured to connect to three sensors 36 and a pressure regulator 34, each of the three sensors 36 being connected to one of the four ports 44, and the pressure regulator 34 being connected to the fourth of the four ports 44. The channels 42 include multiple bends 130. The bends 130 serve as airflow restrictors, thereby affecting a reference... Figure 3 The calculated time differences 104 and 106 are discussed, along with the accuracy and precision of the distributed inflatable touch sensing system 30. A second example of the one-dimensional sensing airbag array 118 shows that the channel 42 can travel along any desired path, thereby creating a bend 130 that can affect airflow.

[0059] refer to Figure 5d A third example of a one-dimensional sensing airbag array 120 is shown. The one-dimensional sensing airbag array 120 includes nine airbags 40, four ports 44, and multiple channels 42. The one-dimensional sensing airbag array 120 is configured to connect to three sensors 36 and a pressure regulator 34. Each of the three sensors 36 is connected to one of the four ports 44, and the pressure regulator 34 is connected to the fourth of the four ports 44. The airbags 40 are arranged in a circular pattern, such that the one-dimensional sensing airbag array 120 can be used to simulate a knob.

[0060] refer to Figure 5e A fourth example of a one-dimensional sensing airbag array 122 is shown. The one-dimensional sensing airbag array 122 includes sixteen airbags 40, four ports 44, and multiple channels 42. The one-dimensional sensing airbag array 122 is configured to be connected to three sensors 36 and a pressure regulator 34. Each of the three sensors 36 is connected to one of the four ports 44, and the pressure regulator 34 is connected to the fourth of the four ports 44. The airbags 40 are arranged such that they appear to form a two-dimensional grid. However, the airbags 40 are connected via the channels 42 to form a one-dimensional array as described above.

[0061] refer to Figure 5f The diagram illustrates a two-dimensional sensing airbag array 132. Two-dimensional means that the airbags 40 are fluidly connected in a two-dimensional grid via channels 42. Therefore, each airbag 40 is connected to each adjacent airbag 40 via channels 42. The two-dimensional sensing airbag array 132 requires at least four sensors 36 to determine which airbag 40 has been pressed by the user.

[0062] The two-dimensional sensing airbag array 132 includes sixteen airbags 40, five ports 44, and multiple channels 42. The two-dimensional sensing airbag array 132 is configured to connect to four sensors 36 and a pressure regulator 34. Each of the four sensors 36 is connected to one of the five ports 44, and the pressure regulator 34 is connected to the fifth of the five ports. The sixteen airbags 40 are arranged to form a two-dimensional grid, and the airbags 40 are connected via the channels 42 to form the two-dimensional array as described above.

[0063] In another aspect of this disclosure, a method is provided for manufacturing a sensing airbag array 32 for a distributed inflatable touch sensing system 30. (See reference...) Figure 2 and Figure 5b The method includes cutting a mask 74 into a shape that defines a plurality of airbag portions 76, channel portions 78, and port portions 80.

[0064] The method also includes disposing of porous material 128 on each of the plurality of channel portions 78 of mask 74, and attaching the mask 74, on which porous material 128 is disposed, to the inner surface 50 of the first thermoplastic sheet 46. The step of disposing of porous material 128 enables the creation of very narrow channels or the inclusion of constraints within the channels by utilizing porous material 128 as part of mask 74. If narrow or constrained channels are not required, the step of disposing of porous material 128 can be omitted.

[0065] The method also includes removing multiple channel portions 78 of the mask 74 such that the porous material 128 remains between each of the multiple airbag portions 76. Alternatively, if the step of setting the porous material 128 is omitted, the multiple channel portions 78 of the mask 74 may remain in place.

[0066] The method further includes placing a second thermoplastic sheet 60 on a first thermoplastic sheet 46. The portions of the inner surfaces 50 and 64 of the first and second thermoplastic sheets 46 and 60 that contact the mask 74 or the porous material 128 are defined as masked portions. The portions of the inner surfaces 50 and 64 of the first thermoplastic sheet 46 and the second thermoplastic sheet 60 that do not contact the mask 74 or the porous material 128 are defined as unmasked portions.

[0067] The method further includes fusing an unmasked portion of the inner surface of the first thermoplastic sheet 46 to an unmasked portion of the inner surface of the second thermoplastic sheet 60 to form a heat seal. The heat seal is formed by applying heat and pressure to the first thermoplastic sheet 46 and the second thermoplastic sheet 60, which melts the unmasked portions of the sheets 46 and 60. The heat-sealing process forms an airtight volume 134 defining the air bladder 40, the channel 42, and the port 44.

[0068] The mask 74 can be made of cellophane or a soluble paper sheet, allowing it to be washed away after heat sealing. The porous material 128 can be removed after heat sealing, leaving small channels 42, or left in the sensing airbag array 32 to provide the information described above. Figure 5b The limitations discussed.

[0069] In another exemplary embodiment, the sensing airbag array 32 can be manufactured using a three-dimensional (3D) printer, plastic molding or laser welding process or chemical bonding process.

[0070] The distributed inflatable touch sensing system 30 disclosed herein offers several advantages. For example, the system 30 is thin, has minimal electrical wiring, and is resistant to electrical noise. Furthermore, electrical components such as sensors and processors can be placed separately from the sensing airbag array. Due to the flexibility of the material and the absence of electronics within the sensing airbag array 32, the sensing airbag array 32 can be deployed on complex surfaces or the surface of the inflatable device. Additionally, adjusting the pressure within the sensing airbag array 32 allows it to deflate when not in use. Advantageously, by stacking multiple sensing airbag arrays 32 and selectively inflating or deflating specific sensing airbag arrays within the stacked array, various arrangements of the airbags 40 and the resulting various interfaces can be presented to the user. The method disclosed herein for manufacturing the sensing airbag array 32 also offers several advantages. Even with complex mask 74 shapes, the method can be performed quickly and at low cost. Furthermore, the shape of the mask 74 can be easily changed without altering the method steps, with minimal cost and time loss. The method of this disclosure produces a thin, flat, flexible, and easy-to-clean sensing airbag array 32.

[0071] The description in this disclosure is merely exemplary in nature, and variations thereof without departing from the spirit and scope of this disclosure are intended to be within its scope. Such variations should not be considered as departing from the spirit and scope of this disclosure.

Claims

1. A distributed inflatable touch sensing system, comprising: Sensing airbag array, including: Multiple airbags; Multiple ports; Multiple channels are in fluid communication with the multiple airbags and the multiple ports, each of the multiple channels having a volume; A pressure regulator for regulating the pressure in the sensing airbag array, wherein the pressure regulator is in fluid communication with at least one of the plurality of ports; Multiple sensors for measuring pressure in the sensing airbag array, wherein each of the multiple sensors is in fluid communication with at least one of the multiple ports; and A processor, communicating with the plurality of sensors, the processor being configured to receive a plurality of pressure measurements from the plurality of sensors and determine which of the plurality of airbags has been pressed by the user; The sensing airbag array further includes: A first thermoplastic sheet having an inner surface and an outer surface, the inner surface having a sealed portion and a plurality of non-sealed portions; and A second thermoplastic sheet has an inner surface and an outer surface. The inner surface has a sealed portion and a plurality of non-sealed portions. The sealed portion of the inner surface of the first thermoplastic sheet is fixedly attached to the sealed portion of the inner surface of the second thermoplastic sheet. A first of the plurality of non-sealed portions of the inner surface of the first thermoplastic sheet and a first of the plurality of non-sealed portions of the inner surface of the second thermoplastic sheet form a plurality of air bladders. A second of the plurality of non-sealed portions of the inner surface of the first thermoplastic sheet and a second of the plurality of non-sealed portions of the inner surface of the second thermoplastic sheet form a plurality of channels. The plurality of channels are in fluid communication with the plurality of air bladders. A third of the plurality of non-sealed portions of the inner surface of the first thermoplastic sheet and a third of the plurality of non-sealed portions of the inner surface of the second thermoplastic sheet form a plurality of ports. The plurality of ports are in fluid communication with the plurality of air bladders. The first thermoplastic sheet and the second thermoplastic sheet are made of materials selected from polyethylene, thermoplastic polyurethane and polypropylene.

2. The distributed inflatable touch sensing system according to claim 1, wherein the sealing portion of the inner surface of the first thermoplastic sheet and the sealing portion of the inner surface of the second thermoplastic sheet are fixedly attached by heat sealing.

3. The distributed inflatable touch sensing system of claim 1, wherein the processor is programmed to receive a plurality of pressure measurements from each of the plurality of sensors within a fixed time period, determine the time when each of the plurality of sensors measures a maximum pressure, and use a predetermined algorithm to calculate which of the plurality of airbags has been pressed by the user, wherein the predetermined algorithm is at least in part based on the time when each of the plurality of sensors measures the maximum pressure; The predetermined algorithm further includes: calculating the difference between the time when the first of the plurality of sensors measures the maximum pressure and the time when the second of the plurality of sensors measures the maximum pressure; The calculated difference between the time when the first of the plurality of sensors measures the maximum pressure and the time when the second of the plurality of sensors measures the maximum pressure depends at least in part on the volume of each of the plurality of channels; The plurality of airbags and the plurality of channels are arranged to form a one-dimensional array, and the plurality of sensors are three sensors; The predetermined algorithm further includes: calculating the identifier value using the following formula: ； Where x defines the identifier value, t1 defines the time when the first of the plurality of sensors measures the maximum pressure, t2 defines the time when the second of the plurality of sensors measures the maximum pressure, and t3 defines the time when the third of the plurality of sensors measures the maximum pressure; The predetermined algorithm further includes comparing the identifier value with multiple predetermined ranges corresponding to each of the plurality of airbags, and determining which of the plurality of airbags has been pressed by the user when the identifier value falls within a predetermined range corresponding to one of the plurality of airbags.

4. The distributed inflatable touch sensing system of claim 3, wherein at least one of the channels includes a constraint defined by at least one of porous material, bending, and reduction of cross-sectional area, wherein the calculated difference depends at least in part on the constraint in at least one of the channels.

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