Abstract
A device is provided that includes an electrically conductive structure on a non-conductive substrate for generating a time-dependent signal on a capacitive surface sensor. A method for generating a tamper-proof time-dependent signal on a surface sensor is also provided by means of such a device. A system or kit for carrying out the method and generating a time-dependent, tamper-proof signal on a capacitive surface sensor is also provided.
Claims
1. A method of generating a tamper-proof time-dependent signal on a surface sensor (20) comprising: a) providing an apparatus (22) having a capacitive surface sensor (20) and a device (10) comprising an electrically conductive structure (12) having structural elements (13) on a non-conductive substrate (14) for generating static signals (40) on the capacitive surface sensor (20); b) placing the device (10) on the surface sensor (20), thereby generating a set of static signals (40) on the surface sensor (20); and c) providing a dynamic input in the form of a movement and/or a gesture with an input means for generating an input signal (44) which is suitable for deflecting the static signals (40) on the capacitive surface sensor (20) and converting the static signals (40) into dynamic signals (42) so that the dynamic input signal (44) and the dynamic signals (42) represent a time-dependent overall signal (46) which can be evaluated by the apparatus (22) containing the surface sensor (20).
2. The method according to claim 1, characterized in that each structural element (13) on the capacitive surface sensor generates a respective static signal (40), the signals (40) being essentially characterized by a time stamp information and a set of coordinate pairs.
3. The method according to claim 1 characterized in that the deflection of the static signals (40) takes place at a time t when the respective structural elements (13) of the electrically conductive structure (12) and the input means (30) are in interaction with a same row (24) and/or a same column (26) of an electrode grid of the capacitive surface sensor (20).
4. The method according to claim 1, characterized in that the dynamic input comprises guiding the input means (30) over the surface sensor (20), which comprises at least sweeping rows (24) and/or columns (26) of the electrode grid on which the structural elements (13) of the device (10) are presently positioned.
5. The method according to any one of the preceding claims claim 1, characterized in that the dynamic input is performed by means of two or more input means (30).
6. The method according to claim 1, characterized in that the electrically conductive structure (12) and in particular the structural elements (13) determine the direction and intensity of the deflection of the signals (40) and the characteristics of the deflected signals (42).
7. The method according to claim 1, characterized in that the method comprises an evaluation of the time-dependent overall signal (46) by the apparatus (22) including the surface sensor (20), wherein in particular the amplitude and/or velocity of the deflection of the static signals (42) is determined in response to the dynamic input.
8. The method according to claim 1, characterized in that the device (10) is a card-shaped object.
9. The method according to claim 1, characterized in that the device is a three-dimensional object, a package or a folding box.
10. The method according to claim 1, characterized in that an edge of the device (10) is used for guiding an input by means of the input means (30).
11. A device (10) for generating a tamper-proof time-dependent signal on a surface sensor (20) in a method according to claim 1, characterized in that the device (10) comprises an electrically conductive structure (12) with structural elements (13) on a non-conductive substrate (14) for generating a time-dependent signal (46) on a capacitive surface sensor (20), wherein by placing the device (10) on a capacitive surface sensor (20) a set of essentially static signals (40) can be generated on the capacitive surface sensor (20), which can be deflected and converted into dynamic signals (42) by an additional dynamic input by means of an input means (30).
12. The device (10) according to claim 1, characterized in that the structural elements (13) are linear and have a width of 0.5 mm to 8 mm.
13. The device (10) according to claim 11 characterized in that the device comprises at least one edge for guiding the input means (30) and predetermining a dynamic input signal (44), wherein the structural elements (13) are line-shaped and have an angle with the orthogonal of said edge of ±75°.
14. A system for generating a tamper-proof time-dependent signal (46) on a capacitive surface sensor (20), the system comprising a device (10) and an apparatus (22) comprising a capacitive surface sensor (20), characterized in that a) the device (10) comprises an electrically conductive structure (12) having structural elements (13) on a non-conductive substrate (14) adapted to generate a set of static signals (40) on the capacitive surface sensor (20), b) the static signals (40) can be deflected and converted into dynamic signals (42) by an additional input by means of an input means (30) on the capacitive surface sensor (20), and c) the dynamic input signal (44) generated by the input means (30) and the dynamic signals (42) represent a time-dependent overall signal (46) which is evaluated by the apparatus (22) comprising the surface sensor (20).
15. The system according to claim 14, characterized in that the electrically conductive structure (12), in particular the structural elements (13) and/or the input means (30) can be brought into operative contact with the capacitive surface sensor (20).
16. The system according to claim 14 characterized in that the system comprises a data processing device which is adapted to evaluate the time-dependent overall signal (46), wherein preferably on the data processing device a software (‘app’) is installed comprising commands for determining dynamic characteristics of the time-dependent overall signal (46) and comparing the dynamic characteristics with reference data.
17. The system according to claim 16 characterized in that the apparatus (22) including the surface sensor (20) processes the time-dependent overall signal (46) as a set of touch events and the software determines dynamic characteristics of the set of touch events.
18. The system according to claim 16 characterized in that the dynamic characteristics comprise a start, an end, local maxima, local minima, velocities, deflections and/or amplitudes of touch events.
19. A kit for carrying out a method according to claim 1 comprising a) a device (10) comprising an electrically conductive structure (12) with structural elements (13) on a non-conductive substrate (14) for generating a time-dependent overall signal (46) on a capacitive surface sensor (20), wherein by placing the device (10) on a capacitive surface sensor (20) a set of essentially static signals (40) can be generated on the capacitive surface sensor (20), which can be deflected by an additional dynamic input by means of an input means (30) and converted into dynamic signals (42), and b) a software (‘app’) for installation on an apparatus (22) including a surface sensor (20), comprising commands to determine dynamic characteristics of the time-dependent overall signal (46) and to compare the dynamic characteristics with reference data characterized in that the visually marked input areas (16) are strip-shaped input areas, the ends of which are marked with numbers, letters, and/or symbols, and wherein the electrically conductive structure (12) comprises multiple line-shaped single elements (14) and each strip-shaped area overlaps with at least one line-shaped single element (14), wherein preferably the line-shaped single elements (14) are arranged orthogonally to the input areas (16) and have different lengths.
Description
[0121] FIG. 1 shows a device (10) comprising an electrically conductive structure (12) comprising a plurality of structural elements (13) arranged on a non-conductive substrate (14) for generating a time-dependent overall signal (46) on a capacitive surface sensor (20), characterized in that the electrically conductive structure (12) of the device (10) generates a set of essentially static signals (40) on the capacitive surface sensor (20) and the static signals (40) are deflected and converted into dynamic signals (42) by an additional dynamic input by an input means (30).
[0122] In the illustrated embodiment, the device (10) represents a three-dimensional object, e.g., a folding box. The electrically conductive structure (12) is arranged on the bottom surface and a side surface of the three-dimensional object. In the exemplary embodiment, three structural elements (13) of the electrically conductive structure (12) are depicted. The bottom surface is in operative contact with the capacitive surface sensor (20) (FIG. 1a), and the structural elements (13) generate substantially static signals (40) on the capacitive surface sensor (20) (FIG. 1b) when the device (10) has been placed on said surface sensor (20). The positions of the static signals (40) correspond to the centroid of the surface of the structural elements (13).
[0123] FIG. 1c shows a dynamic input using an input means (30) on the capacitive surface sensor (20). In the embodiment a finger is used. The input occurs in a linear movement (32) along a side surface of the device (10). The input means (30) does not touch the electrically conductive structure (12).
[0124] FIG. 1d shows the dynamic input signal (44) generated by the dynamic input using an input means (30) and the deflected signals (42). The deflection of the signals is preferably in the direction of the input signal along the structural element (13). The entirety of the deflected signals (42) as well as the dynamic input signal (44) form the time-dependent overall signal (46), which can be evaluated by the device (22) containing the surface sensor (20).
[0125] It should be noted that the recorded signals are shown in the figures. For the person skilled in the art, it is understandable that, for example, the input signal (44) is created gradually on the surface sensor (20) during the input. In the sense of a suitable representation, the time-dependent signals have been “recorded” and the result shown.
[0126] FIGS. 2a-d show the generation of the time-dependent overall signal (46) in a time sequence. To simplify the illustration, the bottom side of a three-dimensional object (10) comprising three structural elements (13) of the electrically conductive structure (12) is shown in each case. The input means (30) is shown in the form of a circle for simplicity. The signals (40, 42, 44, 46) generated on the capacitive surface sensor (20) are shown in the form of crosses representing the coordinates of the respective signals (40, 42, 44, 46). Again, the time-dependent signals were “recorded” and shown in collected form to track the history of the positions and the direction of movement of the signals. It should be noted that when the signals are deflected, the signals originally present in the initial position are not present at the time of the deflection, but are included here for better traceability.
[0127] FIG. 2a left shows the device (10) placed on the capacitive surface sensor (20). FIG. 2a right shows the substantially static signals (40) generated by the structural elements (13) of the electrically conductive structure (12) on the capacitive surface sensor (20). The position of the static signals (40) on the capacitive surface sensor (20) correspond to the centroids of the structural elements (13) of the electrically conductive structure (12).
[0128] FIG. 2b left shows additionally the input means (30) which is placed at the edge of the device (10) and generates an input signal (44) on the capacitive surface sensor (20) (FIG. 2b right). FIG. 2b represents the beginning of the dynamic input.
[0129] FIG. 2c left shows the progression of the dynamic input by input means (30) in the form of a linear movement (32) along the edge of the device (10). FIG. 2c right shows the evolving input signal (44) and the deflection of the static signal generated by the left of the three structural elements (13). A deflected signal (42) is generated at the point when the input means (30) and the structural element (13) are at the same level, i.e. interacting with the same row (not shown) of the capacitive surface sensor (20). The deflection of the signal is in the direction of the input signal (44) and occurs along the structural element (13). In other words, the design of the structural element (13) determines the direction and intensity of the deflection of the signal.
[0130] FIG. 2d left shows the completion of the movement of the input means (30) at the edge between the device (10) and the capacitive surface sensor (20). FIG. 2d right shows the overall dynamic signal (46) consisting of the deflected signals (42) and the dynamic input signal (44), which can be evaluated by the apparatus (22) containing the surface sensor (20).
[0131] The drawing illustrates that the substantially static signals (40) move along the structural elements (13) in the direction of the input means (30) and thus transform into dynamic signals (42).
[0132] FIG. 3 shows a similar object as FIG. 2c, but supplemented by the representation of the electrode grid (24, 26) of the capacitive surface sensor (20). The rows (24) and columns (26) of the electrode grid are arranged orthogonally to each other. In the example shown, the input means (30) interacted with four electrode rows (24). Accordingly, the static signal (40) generated by the left of the three structural elements (13) has been deflected and converted into a dynamic signal (42) as said structural element interacts with at least one of these rows (24).
[0133] FIG. 4a-c shows the formation of the time-dependent overall signal (46) in a time sequence. The device (10) in the exemplary embodiment is a card-like object on which the electrically conductive structure (12) is arranged. The input means (30) is shown in the form of a circle for simplicity. The signals (40, 42, 44, 46) generated on the capacitive surface sensor (20) are shown in the form of crosses representing the coordinates of the respective signals (40, 42, 44, 46). Also in this case the time-dependent signals were “recorded” and shown in collected form to track the history of the positions and the direction of movement of the signals. It should be noted that when the signals are deflected, the signals originally present in the initial position are not present at the time of deflection, but are included in the illustration for better traceability.
[0134] FIG. 4a on the left shows the device (10) in the form of a card-shaped object placed on a capacitive surface sensor (20). The figure shows the input means (30) placed on the edge of the device (10), at the beginning of the movement. FIG. 4a right shows the static signals (40) generated by the electrically conductive structure (12) and the signal (44) generated by the input means (30).
[0135] FIG. 4b left shows the continuous movement (32) of the input means (30) along the edge of the device (10). FIG. 4b right shows the evolving input signal (44) and the deflection of the static signal generated by the left portion of the electrically conductive structure (12). A deflected signal (42) is created at this point when the input means (30) and static signal (40) are at the same level, i.e., interacting with the same row (not shown) of the capacitive surface sensor (20).
[0136] FIG. 4c left shows the completion of the movement of the input means (30) at the edge between the device (10) and the capacitive surface sensor (20). FIG. 4c right shows the overall dynamic signal (46) consisting of the deflected signals (42) and the dynamic input signal (44), which can be evaluated by the apparatus (22) containing the surface sensor (20).
[0137] The drawing illustrates that the substantially static signals (40) move along the electrically conductive structure (12) in the direction of the input means (30), thus converting them into dynamic signals (42).
[0138] FIG. 5 shows the movement of an input means (30) along an edge formed between the surface sensor (20) and the device (10). The device (10) has an electrically conductive structure (12), which can be arranged on the bottom side and/or a side surface of the device (10), whereby the input means is not in contact with the electrically conductive structure (12). By moving the input means (30) along the transition area between the surface sensor (20) and the device (10), a dynamic input is preferably performed, which leads to a conversion of the static signals into dynamic signals.
[0139] FIGS. 6a-c show a particular embodiment of the invention. The device (10) in the exemplary embodiment is a three-dimensional object on which the electrically conductive structure (12) comprising three structural elements (13) is arranged on the substrate material (14). In the present exemplary embodiment, two input means (30) are used, for example two fingers. The input means (30) are shown in the form of circles for simplicity. The signals (40, 42, 44, 46) generated on the capacitive surface sensor (20) are shown in the form of crosses representing the coordinates of the respective signals (40, 42, 44, 46). Also in this case the time-dependent signals were “recorded” and shown in collected form to track the history of the positions and the direction of movement of the signals. It should be noted that when the signals are deflected, the signals originally present in the initial position are not present at the time of deflection, but are included in the illustration for better traceability.
[0140] FIG. 6a shows the device (10) in the form of a three-dimensional object placed on a capacitive surface sensor (20). The figure shows two input means (30), each placed on two different edges of the device (10), at the beginning of the movement. The direction of movement (32) of the two input means (30) is shown by arrows. The movement (32) occurs along two edges of the object (10). In the present embodiment, the two input means (30) are preferably two fingers, for example the user's thumb and index finger. Both fingers are moved towards each other as shown by the arrows.
[0141] FIG. 6b shows the advancing input signals (44), the static signals (40) generated by the electrically conductive structure (12), and the deflection of the “bottom” static signal generated by the bottom structural element (13) of the electrically conductive structure (12). A deflected signal (42) is generated at the point when the lower input means (30) and the static signal (40) are at the same level, i.e., interacting with the same row (not shown) of the capacitive surface sensor (20).
[0142] FIG. 6c shows the complete input signals (44) and the deflected signals (42) after both input means (30) have been moved towards each other to the right edge of the object (10). The time-dependent overall signal (46) comprises the static signals (40), the deflected signals (42) and the input signals (44). For better clarity, the time-dependent overall signal (46) is not shown in this illustration.
[0143] FIG. 7 shows the steps of processing and evaluating the touch events or touches with the help of a software program. Preferably, the device parameters of the apparatus containing the surface sensor, e.g. the resolution of the touch screen, are determined first. Depending on the device, the signal comprising a set of touch events is preferably pre-filtered in the next step and specific characteristics of the signal are amplified or adjusted. Subsequently, the signal is checked for plausibility by calculating parameters such as temporal course of the signal, velocity and data density, checking them for possible manipulation and comparing them with known threshold values. It is preferred that subsequently various characteristics and parameters of the signal are determined or calculated, including the characteristic values start of the signal, end of the signal, local maxima and minima, local velocities of the signal, displacement, amplitudes, if necessary period length of periodic signals and if necessary further characteristics, in order to convert the signal into a comparable data set. In particular, it is preferred to subsequently compare this data set with other data sets and to assign the data set to a known data set located, for example, in a database, and thus to decode the signal. In a further preferred embodiment, the matching of the data set takes place using a machine learning model (artificial neural networks) previously created from recordings. It was surprising that the use of a machine learning model to decode the signal is particularly suitable for complex signals with many different parameters.
LIST OF REFERENCE SIGNS
[0144] 10 Device
[0145] 12 Electrically conductive structure
[0146] 13 Structural elements of the electrically conductive structure
[0147] 14 Substrate
[0148] 20 Capacitive surface sensor
[0149] 22 Apparatus comprising a capacitive surface sensor
[0150] 24 Row of the electrode grid of the capacitive surface sensor
[0151] 26 Column of the electrode grid of the capacitive surface sensor
[0152] 30 Input means
[0153] 32 Movement
[0154] 40 Signal
[0155] 42 Deflected signal
[0156] 44 Input signal
[0157] 46 Time-dependent overall signal
