WO2016027113A1

WO2016027113A1 - Pairing of wireless communication devices by pressing the devices together

Info

Publication number: WO2016027113A1
Application number: PCT/IB2014/001597
Authority: WO
Inventors: Anton Werner Keller
Original assignee: Thomson Licensing
Priority date: 2014-08-22
Filing date: 2014-08-22
Publication date: 2016-02-25

Abstract

Force detecting sensors (60-66, 60'-66') such as of the piezoelectric type are attached to a corresponding edge or side (80, 90) of each of a pair of mobile devices (50, 50'). In order to make the physical contact, the sensors (60-66, 60'-66') disposed along the edge (80, 90) of one of the pair of mobile devices (50, 50') are pressed against the sensors (60-66, 60'-66') disposed along the edge (80, 90) of the other one of the pair of mobile devices (50, 50') for applying force (81) to corresponding sensors (60-66, 60'-66') of the pair. Each of the mobile devices (50, 50') analyzes the output of its sensors (60-66, 60'-66') for identifying the distribution of the force (81) or force profile along its edge (80, 90). This information is then electromagnetically transmitted, for example, by wireless communication and picked up by the other device for performing a comparison between the distribution of the force (81) along the edge (80, 90) of one of the devices with the distribution of the force (81) along the edge (80, 90) of other one of the devices. When such comparison yields a match, the mobile devices (50, 50') are deemed to authenticate each other and data transfer between the two mobile devices is authorized.

Description

PAIRING OF WIRELESS COMMUNICATION DEVICES

BY PRESSING THE DEVICES TOGETHER

Field of the Invention

The present invention relates generally to mobile device user interface systems and more particularly to user interface for verifying touch contact to a second device.

Background of the Invention

Pairing can be negotiated by the two mobile devices using conventional Near field communication (NFC), Bluetooth or Wi-Fi. NFC is a set of standards for smartphones and similar devices to establish wireless communication with each other, referred to as pairing. As used herein, the term "mobile device" refers to any one or all of cellular telephones, personal data assistants (PDAs), tablet computers, multimedia Internet enabled cellular telephones (e.g., the Blackberry Storm.RTM.), and similar electronic devices that include a programmable processor, memory, and force sensitive piezoelectric foils or membranes.

Pairing can be triggered by a manual request (pressing a button), a physical contact or, in the case of NFC, just proximity. For example, the user touches the NFC compatible device to another NFC compatible device for exchanging contact information. In this case, the mere touch activates the pairing process. Alternatively, wireless communication such as NFC, Bluetooth or Wi-Fi is activated by a button to start the pairing process. An advantage of NFC pairing is that it demands real proximity and provides the added security against undesirable pairing with a device stranger to the transaction that happened to be somewhere in the vicinity.

To initiate pairing between a Bluetooth compatible first mobile device and a Bluetooth compatible second mobile device, for example, the first mobile device transmits a 4-digit pseudo random number. The second mobile device located in the vicinity, such as within 50 yards, upon receiving the transmitted 4 digit number would display the 4-digit number on its display device. A user who controls the pairing will view the displayed 4 digit number and will then input this viewed number to an input interface of the first mobile device. If the number input by the user is the same as the number transmitted, pairing is successful and

communication between the first and second mobile devices begins. It may be desirable to simplify the initiation of the pairing process.

It is known to utilize, for example, piezoelectric foils or membranes for detecting the presence of force perpendicular to a surface of a mobile device. For example, United States Patent No. 8,432,368 describes the use of pietzoelectric foils in a mobil device. The foil has a thickness in a range of about 10- 200um. Piezoelectric foils are made of at least three layers, two conductive layers and a piezoelectric layer. The piezoelectric material generates an electrostatic voltage that is in a range of several mV to IV and is proportional to the force applied. This voltage has to be buffered by a high impedance amplifier. One amplifier for each sensor may be needed. For further processing, an output signal of the piezoelectric sensor is digitised by an analog-to- digital (A/D ) converter and fed to a microprocessor.

In carrying out an inventive concept, force detecting sensors such as of the piezoelectric type are attached to a corresponding edge or side of each of a pair of mobile devices. In order to make the physical contact, the sensors disposed along the edge of one of the pair of mobile devices are pressed against the sensors disposed along the edge of the other one of the pair of mobile devices for applying force to corresponding sensors of the pair. Each of the mobile devices analyzes the output of its sensors for identifying the distribution of force or force profile along its edge. This information is then electromagnetically transmitted, for example, by NFC or Bluetooth protocol and picked up by the other device for performing a comparison between the distribution of the force along the edge of one of the devices with the distribution of the force along the edge of other one of the devices. When such comparison yields a match, the mobile devices are deemed to authenticate each other and data transfer between the two mobile devices is authorized. Conversely, if such comparison does not yield a match, pairing and further data transfer between the two mobile devices is prevented. This arrangement, advantageously, provides an advantageous alternative for the conventional pairing process that was referred to before.

Summary of the Invention

An apparatus, embodying an inventive feature, is used for identifying a first device external to a mobile device that is brought to make a physical contact with the mobile device. It includes a force sensitive sensor system contained in the mobile device for sensing magnitudes of a plurality of forces produced by the physical contact and distributed among a plurality of locations, respectively, of the sensor system. A processor is responsive to the sensed plurality of forces and to an input signal produced externally to said mobil device for identifying, in

accordance with information contained in the input signal and in accordance with a manner the magnitudes of the plurality of forces are distributed, whether or not the first device is associated with the input signal.

Brief Description of the Drawings

Figure 1 A illustrates a front view of a mobile device, in accordance with an aspect of the invention;

Figure IB illustrates a side view of the mobile device of Figure 1A;

Figure 2A illustrates a pair of mobile devices that are not in physical contact; Figures 2B, 2C and 2D illustrate corresponding examples of the pair of mobile devices of Figure 2A that are in physical contact;

Figure 3 is a simplified flowchart of a process for authenticating or verifying the mobile devices of Figures 2A-2D to each other; and

Figure 4 illustrates a block diagram of a circuit that implements the process of Figure 3.

Detailed Description

Figure 1 A illustrates a front view and Figure IB illustrates a side view of a mobile device 50. Mobile device 50 includes a case 70 which may be a metal alloy, a plastic, or any substance typically used for mobile device housings. Mobile device 50 has, for example, seven force sensitive squeeze or grip detectors or sensors 60, 61, 62, 63, 64, 65 and 66 that are substantially identical and are attached to a right side or edge 80 of case 70. Similarly, seven force sensitive squeeze or grip detectors or sensors 60', 6Γ, 62', 63', 64', 65' and 66' that are substantially identical are attached to a left side 90 of case 70. Each one of detectors 60-66 and 60' -66' includes a force sensing material implemented on or within case 70 in the form of force sensitive strip to form, for example, a

corresponding pietzoelectric detector. For example, detector 60 includes a force sensitive strip 60a, not shown in details. Similarly, detectors 61, 62,63, 64, 65 and 66 include force sensitive strips 61a, 62a, 63a, 64a, 65a and 66a, respectively. Force sensitive strips 60a- 66a are positioned on left side or edge 90 and on right side or edge 80 in a symmetrical manner. Each of force sensitive strips 60a- 66a may be made of any material capable of generating a measurable electrical signal in response to applied force or pressure, or induced strain. Force sensitive strips 60a- 66a may be placed on the exterior of mobile device 50 so that each of sensors 60-66 can generate a signal in response to user actions such as tapping, squeezing, and/or swiping a finger on the material itself.

FIGURE 2A illustrates a front view of a pair of mobile devices that includes mobile device 50 of Figures 1A and IB and, for example, an identical, second mobile device 50' . Mobile devices 50 and 50' of Figure 2A are placed side-by- side without touching each other prior to establishing wireless contact

therebetween. Similar symbols and numerals in Figures 1 A, IB and 2A indicate similar items or functions.

Along each of side edges 80 and 90 of mobile device 50 of Figure 2A and of mobile device 50', force sensitive strips 60a-66a of Figure 1 are distributed in a direction X in the manner described before with respect to Figure 1 A. When an external force 81 of Figure 2A is applied in a direction Y that is perpendicular to direction X to at least one of mobile devices 50 and 50', edge 80 of mobile devices 50 and edge 90 of mobile devices 50', respectively, they become closer to each other and ultimately touch each other.

Figure 2B shows a first example in which mobile devices 50 and 50' ultimately touch each other along edges 80 and 90, respectively. Similar symbols and numerals in Figures 1A, IB, 2A and 2B indicate similar items or functions. When mobile devices 50 and 50' of Figure 2B touch each other, force sensitive strips 60a, 61a, 62a, 63a, 64a, 65a and 66a of mobile device 50 of Figure 2A contact and apply forces F60a, F61a, F62a, F63a, F64a, F65a and F66a of Figure 2B to force sensitive strips 60a', 61a', 62a', 63a', 64a', 65a' and 66a', respectively, of mobile device 50' of Figure 2A.

In the representative example of Figure 2B, force F60a is applied by strip 60a to strip 60a'. Conversely, force F60a' that is equal but at opposite direction is applied by force sensitive strip 60a' of mobile device 50' to force sensitive strip 60a of mobile device 50. Similarly, forces F61a-F66a are equal and of opposite direction to F61 a'-F66a', respectively. The vectorial sum of forces F60a-F66a is equal and of opposite direction to the vectorial sum of forces F60a'-F66a' .

The above mentioned relationships between the forces are based on the third of Newton's laws of motion of classical mechanics that states that forces always occur in pairs. A force ('action') of Figure 2B on one force sensitive strip of strips 60a-66a of Figure 2A is accompanied by a 'reaction' force of Figure 2B on the corresponding force sensitive strip of strips 60a' -66a' of Figure 2A that is of equal magnitude and opposite direction. Each of the pair of opposite and equal forces can be considered the action. Whereas, the other force is considered as its associated reaction. It should be understood that forces F60a-F66a need not be equal to one another. Similarly, forces F60a'-F66a' also need not be equal to one another.

In order to facilitate the contact between each of strips 60a-66a with each of strips 60a'-66a', respectively, each of strips 60a-66a and 60a'-66a', preferably, should have flexibility to expand or contract in the direction of axis Y. This may be accomplished by providing a flexible layer, not shown, either between a surface of such strip and the corresponding edge 80 or 90 of case 70 on which it is mounted or on an exterior surface of such strip that is intended to make the contact with the corresponding strip of the other mobile device.

Additionally, it may be desirable to reduce the possibility that , for example, strip 60a of mobile device 50 of Figure 2A or 2B might contact directly edge 90 of mobile device 50' instead of a corresponding strip of mobile device 50', when mobile terminals 50 and 50' of Figure 2A or 2B contact each other. Therefore, it may be desirable to mount each of end strips 60a, 66a, 60a' and 66a' close to a corresponding corner , for example, corner 101 of Figure 2A. Fig. 3 is a simplified flowchart of a process for authenticating or verifying mobile devices 50 and 50' to each other of Figure 2B prior to initiating data transfer therebetween. In the authentication process of Figure 3, each of mobile devices 50 and 50' of Figure 2B determines whether or not the other mobile devices, 50 or 50', as the case may be, is in physical contact with it .

Figure 4 includes a block diagram of a circuit 120 of mobile device 50 for performing the process of Figure 3. Similar symbols and numerals in Figures 1A, IB, 2A, 2B, 3 and 4 indicate similar items or functions.

In circuit 120 of Figure 4, output signals of sensors 60-66 and 60'-66' are identified with the same alphanumeric identifiers used for identifying forces F60a- F66a and F60a'-F66a', respectively. This is justified because the output signals of sensors 60-66 and 60' -66' are substantially proportional to forces F60a-F66a and F60a'-F66a', respectively.

In circuit 120 of Figure 4, a processor 100 receives output signals F60a- F66a and F60a'-F66a'. Processor 100 is also coupled to a wireless

receiver/transmitter 110 for receiving an input signal 100a that is coupled from a receiver portion, not shown in details, of receive/transmitter 1 10 and for generating an output signal 100b that is coupled to a transmitter portion, not shown in details, of receiver/transmitter 110. In a step 300 of Figure 3, wireless communication is used by

receive/transmitter 110 of Figure 4 for communicating between mobile devices 50 and 50' of Figure 2B to perform in each the aforementioned authentication or verification process of Figure 3. In a step 310, processor 100 of Figure 4 measures or samples output signals F60a-F66a produced by pietzoelectric sensors 60-66 of mobile device 50 having magnitudes that are proportional to forces F60a-F66a , respectively. From these measured or sampled magnitudes, processor 100 of mobile devices 50 evaluates a distribution of the magnitudes of forces F60a-F66a as a function of distance or sensor position in direction X along edge 80, referred to as a force profile applied to edge 80. In the example of Figure 2B, this force profile may be represented by a graph, not shown, having an ordinate axis with 7 discrete values equal to the magnitudes of forces F60a-F66a, respectively, that are distributed along an abscissa in the direction X. The distribution in direction X of the 7 discrete values corresponds to the locations of strips 60a-66a, respectively, along edge 80 of Figure I A or 4. In the arrangement of Figure 2B there is no need for using interpolation to obtain the force profile because each strip makes contact to only one strip. On the other hand, as explained later on, in the general case, the force profile can be obtained by using well known extrapolation techniques. Simultaneously with the sampling performed by mobile device 50 of Figure 2B, mobile device 50' measures or samples voltages, not shown, produced by pietzoelectric sensors 60' -66', in the same manner as explained before with respect to mobile device 50, having magnitudes that are proportional to forces F60a'- F66a', respectively. From these measured or sampled magnitudes, mobile devices 50' evaluates a distribution of the magnitude of the force applied as a function of distance in direction X along edge 90, referred to, as explained before, as the force profile applied to edge 90. In the example of Figure 2B, this force profile may be represented by a graph, not shown, having an ordinate axis with 7 discrete values equal to F60a'-F66a', respectively, that are distributed along an abscissa in the direction X. The distribution of the 7 discrete values corresponds to the distribution of strips 60'-66', respectively, along edge 90 of Figure 1 A. However, mentioned before, in the general case, the force profile is obtained using well known extrapolation techniques.

In a step 320 of Figure 3, the force profile applied to edge 90 of Figure 2B is transmitted by a transmitter portion of a receiver/transmitter, not shown, of mobile device 50' that, in this example, is identical to receiver/transmitter 110 of mobile device 50 of Figure 4 using, for example, wireless transmission conforming to the Bluetooth standard. Similarly, the force profile applied to edge 80 of Figure 2B is transmitted by receiver/transmitter 110 of mobile device 50 of Figure 4 and received by mobile device 50' of Figure 2B

In a step 330 of Figure 3, the force profile applied to edge 90 of mobile device 50' of Figure 2B received by the receiver portion, not shown, of receiver/transmitter 1 10 of mobile device of Figure 4 produces signal 100a of receiver/transmitter 110 that is applied to processor 100 . In processor 100, the force profile applied to edge 90 of mobile device 50' of Figure 2B is compared with the force profile applied to edge 80 that has been evaluated in processor 100 of mobile device 50. If the received force profile applied to edge 90 of mobile device 50' of Figure 2B is matched to the force profile applied to edge 80 of mobile device 50, then, in a step 340 of Figure 3, mobile devices 50 and 50' of Figure 2B are verified or authenticated as being in physical contact with each other. The result is that pairing is successful and processor 100 of Figure 4 enables data transfer between mobile devices 50 and 50' of Figure 2B.

Determining successful match can be evaluated by first normalizing the force profiles to each other and then evaluating the variation between them in the X-direction. When the variations exceed a threshold, that may be programmable, matching deems to have failed. Conversely, when the variations do not exceed such threshold, matching, hence pairing, deems to have succeeded. When pairing is successful, a procedure from several procedural alternatives may be employed. In a first alternative, the secured connection remains

established in a manner to permit data transfer as long as devices 50 and 50' of Figure 2B remain in the vicinity of each other. In a second alternative, the secure connection is timed and the authentication needs to be performed periodically. In a third alternative, the pressure must be maintained throughout the entire data transfer. The amount of pressure might vary but the two profiles should remain, prefearably, matching. It may also be desirable for each of devices 50 and 50' to indicate to the user or users when successful or unsuccessful authentication, as the case may be, has occurred. This may be accomplished, for example, in a form of a beep.

On the other hand, if the received force profile applied to edge 90 of Figure 2B does not match to the force profile applied to edge 80, then the authentication process may be repeated or retried beginning at step 300 unless a number of retries has exceeded a threshold in which case pairing is deemed to have been failed.

Figure 2C shows a second example in which mobile devices 50 and 50' ultimately touch each other along edges 80 and 90, respectively. Similar symbols and numerals in Figures 1A, IB, 2A, 2B, 2C, 3 and 4 indicate similar items or functions. In the example of Figure 2C, force sensitive strip 61a, 62a, 63a, 64a, 65a and 66a of mobile device 50 of Figure 2 A contact and apply forces F61a, F62a, F63a, F64a, F65a and F66a, respectively, to force sensitive strips 60a', 61a', 62a', 63a', 64a' and 65a' , respectively, of mobile device 50'.

In the representative example of Figure 2C, force F6 la is applied by strip 61a to strip 60a'. Conversely, force F60a' that is equal but at opposite direction is applied via force sensitive strip 60a' of mobile device 50' to force sensitive strip 61a of mobile device 50. Similarly, forces F62a-F66a are equal and of opposite direction to forces F60a'-F65a', respectively. Also, the vectorial sum of forces F61a-F66a is equal and of opposite direction to the vectorial sum of forces F60a'- F65a'.

Figure 2D shows a third example in which mobile devices 50 and 50' ultimately touch each other along edges 80 and 90, respectively. Similar symbols and numerals in Figures 1 A, IB, 2 A, 2B, 2C, 2D, 3 and 4 indicate similar items or functions. In the example of Figure 2D, force sensitive strip 60a of mobile device 50 contacts and applies force F60a to force sensitive strip 60a' of mobile device 50'. Each of force sensitive strip 61a, 62a, 63a, 64a, 65a and 66a of mobile device 50 contacts and applies force F61a, F62a, F63a, F64a, F65a and F66a, respectively, to a corresponding pair of force sensitive strips 60a'-61a', 61a'- 62a', 62a'-63a', 63a'-64a', 64a'-65a' and 65a'-66a', respectively, of mobile device 50'of Figure 2D. Thus, force F60a' is equal to a sum of force F60a and a fraction of force F61a. Also, force F61a' is equal to a sum of a remaining fraction of force F61a and a fraction of force F62a. Likewise, force F62a' is equal to a sum of a remaining fraction of force F62a and a fraction of force F63a. Force F63a' is equal to a sum of a remaining fraction of force F63a and a fraction of force F64a. Force F64a' is equal to a sum of a remaining fraction of force F64a and a fraction of force F65a. Force F65a' is equal to a sum of a remaining fraction of force F65a and a fraction of force F66a. Force F66a' is equal to a remaining fraction of force F66a.

It should be clear that the sum of the aforementioned fraction and its remaining fraction of each force F61a, F62a, F63a, F64a, F65a and F66a is equal to force F61a, F62a, F63a, F64a, F65a and F66a , respectively. Similarly, the sum of the aforementioned fraction and its remaining fraction of each force F61a\ F62a\ F63a', F64a, F65a' and F66a' is equal to force F61a\ F62a\ F63a', F64a, F65a' and F66a', respectively. Also, as explained before, the vectorial sum of forces F60a-F66a is equal and of opposite direction to the vectorial sum of forces F60a'-F66a\

The force profile of forces F60a, F61a, F62a, F63a, F64a, F65a , F66a and the force profile of forces F60a\ F61a\ F62a', F63a', F64a', F65a' and F66a' are obtained using well known interpolation techniques in step 310 of Figure 3 and then transmitted in step 320. It should be understood that, when a larger number of force sensitive strips, similar to, for example, force sensitive strips 60a of Figure 2A, is employed, the accuracy of determining the force profile, hence the match, advantageously, increases.

Claims

1. An apparatus for identifying a first device external to a mobile device that is brought to make a physical contact with said mobile device, comprising:

a force sensitive sensor system contained in said mobile device for sensing magnitudes of a plurality of forces produced by said physical contact and distributed among a plurality of locations, respectively, of said sensor system; and a processor responsive to said sensed plurality of forces and to an input signal produced externally to said mobil device for identifying, in accordance with information contained in said input signal and in accordance with a manner said magnitudes of said plurality of forces are distributed, whether or not said first device is associated with said input signal. .

2. An apparatus according to Claim 1 wherein said first device comprises a communication device and wherein said processor enables communication between said first and mobile devices when said first device is identified as being associated with said input signal.

3. An apparatus according to Claim 1 wherein said sensor system comprises a plurality of force sensing elements associated with said plurality of locations, respectively.

4. An apparatus according to Claim 3 wherein a force sensing element of said plurality of force sensing elements comprises a piezoelectric sensor.

5. An apparatus according to Claim 1 wherein said input signal comprises a wireless signal.

6. An apparatus according to Claim 5 wherein said wireless signal conforms to one of Bluetooth, Wi-Fi and NFC protocols.

7. An apparatus according to Claim 1 wherein said first device comprises a corresponding force sensitive sensor system for sensing magnitudes of a plurality of forces produced by said physical contact and distributed among a plurality of locations, respectively, of said sensor system of said first device and wherein said first device produces said input signal for said mobile device that is indicative of a manner said magnitudes of said plurality of forces are distributed in said force sensitive sensor system of said first device for enabling said processor of said mobile device to identify that said first device is in said physical contact with said mobile device. .

8. An apparatus according to Claim 7 wherein said input signal is communicated to said mobile device by wireless..

9. An apparatus for verifying a physical contact with a mobile device , comprising: a case;

at least one force sensitive sensor of a plurality of force sensitive sensors attached to said case and exposed to an exterior surface of said case for generating a corresponding force indicative signal that varies in accordance with variation of a force applied when an external device makes said physical contact with said at least one force sensitive sensor; and

a processor responsive to an input, first wireless signal communicated from outside of said case and responsive to said corresponding force indicative signal for performing a control operation when a match between a value of said force and a value contained in said wireless signal is detected.

10. An apparatus according to Claim 9 wherein said processor enables further wireless communication in said mobile device when said match is detected.

11. An apparatus according to Claim 9 wherein said wireless communication conforms to one of Bluetooth, Wi-Fi and NFC protocols.

12. An apparatus according to Claim 9 wherein said at least one of said force indicative sensors is mounted on an edge of said case.

13. An apparatus according to Claim 9 wherein said plurality of force sensitive sensors generate a plurality of force sensitive signals when a plurality of forces are applied to said plurality of force sensitive sensors and wherein said processor compares a first force profile contained in said first plurality of force indicative signals with a force profile contained in said wireless signal for detecting said match.

14. An apparatus according to Claim 13 wherein said wireless signal is generated in the same external device that makes said physical contact with said plurality of force sensitive sensors.

15. An apparatus according to Claim 14 wherein said processor enables further wireless communication with said external device.

16. An apparatus according to Claim 9 wherein said processor detects said match by application of the third of Newton's laws of motion of classical mechanics.

17. An apparatus according to Claim 9 wherein for different values contained in said wireless signal, said match is detected when correspondingly different values of said force are applied.

18. A method for verifying a physical contact with a mobile device , comprising:: providing in said mobile device at least one force sensitive sensor of a plurality of force sensitive sensors;

generating in said at least one force sensitive sensor a signal that is indicative of of a value of a force applied when an external device makes said physical contact with said at least one force sensitive sensor that varies in accordance with variation of said value of said force;

receiving a wireless signal;

detecting a match between said value of said force and a value contained in said wireless signal; and

performing a control operation when said match is detected.

19. The method according to Claim 18 wherein said control operation comprises enabling further wireless communication with said mobile device when said match is detected.

20. An method according to Claim 18 wherein said match is detected for different values contained in said wireless signal when correspondingly different values of said force are applied.

21. The method according to Claim 18 further comprising, comparing a first force profile of said first plurality of force indicative signals with a force profile contained in said wireless signal for detecting said match.

22. A method for identifying a first device external to a mobile device that is brought to make a physical contact with said mobile device, comprising:

sensing magnitudes of a plurality of forces produced by said physical contact and distributed among a plurality of locations, respectively, of said sensor system; receiving an input signal produced externally to said mobil device; and

identifying, in accordance with information contained in said input signal and in accordance with a manner said magnitudes of said plurality of forces are distributed, whether or not said first device is associated with said input signal.

23. A method according to Claim 22 wherein said input signal comprises a wireless signal.

24. A method according to Claim 23 wherein said wireless signal conforms to one of Bluetooth, Wi-Fi and NFC protocols.