Switch operating device, mobile device and method for operating a switch by a non-tactile push-gesture

Switch operating device (100) with: a gesture sensor operating a switch (103) with a non-tactile push-gesture performed with a heat emitting part. The gesture has an approach phase (111) during which the part approaches the sensor, a waiting phase (113) during which the part remains proximate to the sensor, and a withdrawal phase (112) during which the part is moved away from the sensor. The sensor detects heat emitted by the part with at least one pixel and outputs per pixel a signal (51 to 54) with signal deflections (56, 57) corresponding to a temporal intensity curve of heat detected by the pixel while the gesture (115) is performed. A signal processing unit (101) which determines performance of the gesture from a temporal succession of signal deflections. An actuator (104) is controlled by the signal processing unit and operates the switch when the gesture is performed.

FIELD OF THE INVENTION

The invention relates to a switch operating device, a mobile device with the switch operating device and a method for operating the switch with the switch operating device by a non-tactile push-gesture, in particular from a human hand.

BACKGROUND

Interactive systems and their human being-machine-interfaces are known for the human being-computer-interaction, wherein the human being-machine-interfaces are provided with a device for the automatic recognition of non-tactile or tactile gestures performed by human beings. The gesture can principally be derived from every posture and every movement of the body, wherein hand gestures have most importance. The gesture recognition device is provided with a device for the optical acquisition in particular of the gesticulating hand, wherein the image information generated thereby is processed with corresponding algorithms in order to derive a gesture out of the image information. The device for the optical acquisition of a non-tactile gesture is conventionally a camera that disadvantageously takes a large space and has high investment costs. Camera-based devices for the gesture recognition in miniaturized design with low costs, which would be for example advantageous for the use in mobile phones, are therefore not to be realized. Furthermore, camera-based devices have disadvantageously a high energy consumption, whereby mobile applications can only be realized with difficulty. High-speed spectrometers are alternatively known, which cannot provide remedy with respect to the miniaturized design with low costs. Touch screens in particular for mobile telephones are furthermore known, however the touch screens are suitable only for the recognition of tactile gestures and not for the recognition of non-tactile gestures.

SUMMARY

It is an object of the invention to provide a switch operating device, a mobile device with the switch operating device and a method for operating a switch with the switch operating device by a non-tactile push-gesture, wherein the switch operating device has a miniaturized design with low costs and low energy consumption and the operation of the switch with the switch operating device is secure and has few errors.

The switch operating device according to the invention comprises a gesture sensor for operating a switch by a non-tactile push-gesture that is to be performed with a part emitting heat and is formed by an approach phase during which the part approaches the gesture sensor, a waiting phase during which the part remains in the proximity of the gesture sensor, and a withdrawal phase during which the part is to be moved away from the gesture sensor, wherein the gesture sensor is adapted to detect heat emitted by the part with at least one pixel comprising a thin film out of pyroelectric material and to output per pixel a signal with signal deflections corresponding to the temporal intensity curve of the heat detected by the pixel during performing the gesture, a signal processing unit with which the performance of the gesture is determined from the temporal succession of the signal deflections, and an actuator that is controlled by the signal processing unit and operates the switch when the performance of the gesture is determined. The pyroelectric material is in particular lead-zirconate-titanate.

The mobile device according to the invention comprises the switch operating device, wherein the switch is interconnected in the mobile device for activation/deactivation of a functionality of the mobile device.

The method according to the invention for operating the switch operating device comprises: performing the non-tactile push-gesture with the part emitting heat, so that the signal deflection generated in the approach phase and the signal deflection generated in the withdrawal phase are output from the pixel to the signal processing unit, wherein a waiting level is reached by the signal between the signal deflections during the waiting phase, wherein the waiting level has a lower absolute value as the level of the signal deflections; monitoring the signal and identifying the occurrence of a succession of the signal deflections and the waiting level being temporally therebetween; when the succession is identified: controlling the actuator for operating the switch by the signal processing unit.

The alternative method according to the invention for operating the switch operating device comprises the steps: performing two immediate temporal consecutive non-tactile push-gestures with the part emitting heat during which the waiting phase lasts respectively zero seconds, so that a succession of signal deflections in shape of the signal deflection generated in the approach phase of the first push-gesture, the signal deflection generated in the withdrawal phase of the first push-gesture, the signal deflection generated in the approach phase of the second push-gesture and the signal deflection generated in the withdrawal phase of the second push-gesture is output from the pixel to the signal processing unit, wherein the signal deflections generated in the approach phases have another direction than the signal deflections generated in the withdrawal phases; monitoring the signal and identifying the occurrence of the succession of the signal deflections; as soon as the succession is identified: controlling the actuator for operating the switch by the signal processing unit.

Because the pixel comprises the thin film made out of the pyroelectric material, preferably lead-zirconate-titanate, the signal generated by the part emitting heat during performing the push-gesture is provided advantageously such that the recognition of the push-gesture with the method according to the invention can be carried out securely and has few errors. The gesture sensor with the pixel can furthermore be made in a miniaturized design with low costs such that the switch operating device can be advantageously used for mobile devices. The signal is generated with the thin film by the part emitting heat, so that the gesture sensor does not need to be supplied with energy by an external energy source. The switch operating device thus comprises the signal processing unit and the actuator as energy consumer, so that the energy consumption of the switch operating device is altogether advantageously low for the mobile device.

The gesture sensor preferably comprises at least two pixels. Therefore, two signals independently generated from each other are provided for the signal processing unit, wherein the processing of the signals and the gesture recognition coming along therewith is advantageously realized redundant.

The part is preferably a human hand and the heat emitted by the part is preferably the body heat radiated by the human hand. The recognition of the non-tactile push-gesture with the human hand is enabled particularly securely and has few errors resulting from the inventive and/or preferred embodiments of the switch operating device in the framework of usual human motion sequences.

The first alternative method according to the invention preferably comprises: verifying, if the temporal delay of the signal deflections is within a first predetermined duration; if the verification is positive, proceeding with the method. It is hereby preferred that the first predetermined duration is between 300 ms and 2000 ms. The first alternative method according to the invention furthermore preferably comprises: verifying, if the signal deflections have different directions; if the verification is positive, proceeding with the method. Further, it is preferred that the amplitude curve of the signal output by the pixel is used for the signal deflections. It is hereby preferred that it is verified, if the absolute value of the waiting level is maximum 20% of the absolute value of the signal level that prevails during a non-responding of the pixel. It is alternatively preferred that the first temporal derivative of the amplitude curve of the signal output by the pixel is used for the signal deflections. It is hereby preferred that it is verified, if the waiting level is maximum 20% of at least one of the absolute values of the signal level of the signal deflections. It is furthermore preferred that it is verified, if the waiting level is substantially zero.

For the second alternative method according to the invention it is preferred that a respective duration is arranged between the signal deflections of the succession, wherein the duration is within a predetermined time range. It is hereby preferred that the predetermined time range is from 100 ms to 1500 ms. Further, the second alternative method according to the invention preferably comprises: verifying, if the absolute values of the signal deflections are above a predetermined level; if the verification is positive, proceeding with the method. Further, it is preferred that the gesture sensor comprises at least two of the pixels and it is preferably verified, if the analogue signal deflections belonging to each other are respectively arranged within a second predetermined duration; if the verification is positive, proceeding with the method. It is hereby preferred that the second predetermined duration is 50 ms.

As it is supposed that the absolute value of the waiting level is maximum 20% of the absolute value of the signal level, it is advantageously achieved that noise that for example is released by influences out of the surroundings of the gesture sensor does not or at least barely affect the gesture processing, whereby the accuracy of the gesture recognition is increased.

By the inventive and/or preferred definition of the sequences of the signal deflections that are assigned to the push-gesture, the accuracy during recognition of the push-gesture out of arbitrate gestures is advantageously high, whereby a secure gesture recognition that has few errors is enabled. If, for example, the sequences of the signal deflections of a performed gesture do not correspond to the signal deflections of the push gesture, this gesture is not interpreted as a push-gesture. By using signal deflections generated by the thin film made out of the pyroelectric material, preferably lead-zirconate-titanate, for the identification of the push-gesture, an increase of the precision of the gesture recognition is surprisingly achieved.

DETAILED DESCRIPTION

A switch operating device100that is built in a mobile device is shown inFIG. 1. The switch operating device100comprises a gesture sensor1and a signal processing unit101that is coupled via a signal line102for transferring signals from the gesture sensor1to the signal processing unit101. The signal processing unit101activates or deactivates an actuator104, with which a switch103of the mobile device can be operated according to the processing of the signals that are transferred from the gesture sensor1to the signal processing unit101. The switch103is interconnected in the mobile device for activating/deactivating a functionality of the mobile device.

The gesture sensor1is provided for detecting push-gestures, wherein, depending on if a push-gesture115was detected, a signal or a plurality of signals are transferred via the signal line102to the signal processing unit101, on which basis the operation of the switch103via the actuator104is carried out. The operation of the switch103is only then triggered when the push-gesture115is identified by the gesture sensor1and by the signal processing unit101.

The gestures are to be performed non-tactile with a hand114in the proximity of the gesture sensor1, wherein heat emitted by the hand114can be detected by the gesture sensor1. The push-gesture115is composed of the temporal immediate sequence of an approach phase111, a waiting phase113and a withdrawal phase112. During performing the push-gesture115the hand114is approached to the gesture sensor101during the approach phase111and after ending of the waiting phase113, during which the hand114remains adjacent to the gesture sensor1, is again withdrawn from the gesture sensor1during the withdrawal phase112.

As an alternative or additionally it is provided that the switch103is operated with two temporally subsequently performed push-gestures that respectively consist only of the approach phase111and the withdrawal phase112, wherein the waiting phase113is respectively zero seconds. That means that with these two push-gestures with the waiting phase113equaling zero seconds the hand114is approached to the gesture sensor1, withdrawn, again approached and then again withdrawn without the hand114remaining in the proximity of the gesture sensor1a substantial duration. The signal processing unit101is adapted such that it identifies the push-gesture with the waiting phase113that lasts longer than zero seconds and/or two immediate consecutive push-gestures, which waiting phases113are respectively zero seconds.

The gesture sensor1comprises a first pixel21, a second pixel22, a third pixel23and a fourth pixel24. The pixels21to24respectively comprise a thin film out of lead-zirconate-titanate with which the signal is respectively generated as soon as heat emitted by the hand114is detected by the respective pixel21to24. The signal with a signal deflection corresponding the temporal intensity curve of the thin film of the corresponding pixel is therefore output from each pixel21to24to the signal processing unit101during performing the push-gesture115with the hand114. The signal of the first pixel21is denoted with the reference sign51, the signal of the second pixel22is denoted with the reference number52, the signal of the third pixel23is denoted with the reference number53, and the signal of the fourth pixel24is denoted with the reference sign54.

A diagram with the temporal amplitude curves of the signals output by the pixels21to24is shown inFIG. 2, wherein the time is plotted over the abscissa61and the amplitude is plotted over the ordinate62. The signals51to54respectively comprise signal deflections56,57, wherein the signal deflections56are generated during the approach of the hand114to the gesture sensor1and the signal deflections57are generated during the withdrawal of the hand114from the gesture sensor1. A waiting duration58is arranged between the signal deflections56,57, wherein the waiting duration58forms the waiting phase113, whereas the signal deflections56form the approach phase111and the signal deflections57form the withdrawal phase112. A signal level55during pixel passivity arises during the waiting phase113, wherein the pixel passivity occurs when no heat emitted by the hand114is detected by the gesture sensor1. The signal level55also arises in advance of the signal deflection56during approach and in the lag of the signal deflection57during withdrawal of the hand114.

Alternatively toFIG. 2, inFIG. 3, the first temporal derivative of the amplitude curves plotted inFIG. 2is illustrated over the ordinate63. A representative detail of one of the signals51to54is shown inFIG. 5, wherein the amplitude of this signal is plotted versus the time. The amplitude curve is in particular formed by a first sampling point71, a second sampling point72, wherein the sampling points71and72are temporally shifted to each other by a time increment73and an amplitude difference74is formed between the sampling points71and72. The temporal derivative is to be formed discrete by a quotient out of the amplitude difference74and the time increment73.

A detail ofFIG. 2is shown inFIG. 4, wherein the signal deflection56during approach of the hand114to the gesture sensor1is illustrated magnified. The curves of the amplitudes of the signals51to54are shown, wherein each of the amplitude curves comprises a minimum81to84. The signals51to54are generated by the push-gesture115according to the first alternative. The four pixels21to24are simultaneously affected during performing of the push-gesture115. The qualitative curve the signals51to54is therefore simultaneous so that the minima81to84occur simultaneously in the point of time91. The push-gesture115is performed such that the hand114is moved towards the gesture sensor1during the approach phase111, remains in the proximity of the gesture sensor1during the waiting phase113the waiting duration58and is again subsequently withdrawn from the gesture sensor1during the withdrawal phase112. The movement of the hand during the approach phase111and the withdrawal phase112is supposed to be substantially perpendicular to the plane defined by the pixels21to24. The pixels21to24simultaneously detect the heat emitted by hand114during performing the push-gesture115.

Arbitrary gestures can be performed by the hand114during the operation of the switch operating device100. However, it is so provided that only during performing the push-gesture115the switch103is supposed to be operated. Therefore, it is to identify the presence of the push-gesture115out of a plurality of possible gestures and noise influences out of the surroundings of the switch operating device100.

The signals51to54are transferred from the gesture sensor1to the signal processing unit101for the identification of the performed gesture. It is verified in the signal processing unit101if the signals51to54comprise the signal deflections56and57, wherein the waiting level55is supposed to be present between the signal deflections56and57during the phase113. Further, it is verified in the signal processing unit101if the temporal delay of the signal deflections56and57is within a first predetermined duration that can be chosen between 300 ms and 2000 ms. It is furthermore verified in the signal processing unit101if the signal deflections56and57have different directions. That means, it is verified if the signal deflection56has a lower level than the waiting level55and the signal deflection57has a higher level than the waiting level55, respectively if the signal deflection56has a higher level than the waiting level55and the signal deflection57has a lower level than the waiting level55. It is additionally verified in the signal processing unit101if the absolute value of the waiting level55is maximum 20% of the absolute value of the signal level that prevails during a non-affection of the pixel. InFIG. 2the signal level during a non-affection of the pixel21to24is equalized with the signal level25during pixel passivity.

In case the verifications in the signal processing unit101result in that the criteria mentioned earlier are fulfilled, the gesture detected by the gesture sensor is identified as the push-gesture115. According to how it is stored in the signal processing unit101, the switch103is operated via the actuator104. Gestures that are not identified as the push-gesture115are rejected in the signal processing unit101. Every arbitrary combination of the verifications in every arbitrary sequence is principally conceivable.

The signal processing unit101is alternatively configured such that two immediate temporal consecutive push-gestures trigger the operation of the switch103by the actuator104. The two immediate temporal consecutive push-gestures have respectively a waiting phase113that lasts zero seconds. A sequence of signal deflections in shape of the signal deflection56generated in the approach phase111of the first push-gesture, the signal deflection57generated in the withdrawal phase112of the first push-gesture, a signal deflection generated in the approach phase of the second push-gesture, and a signal deflection generated in the withdrawal phase of the second push-gesture therefore results. The signal deflections generated in the approach phases have another direction as the signal deflections generated in the withdrawal phases. The switch103is then operated by the signal processing unit101via the actuator104, when a respective duration from 100 ms to 1500 ms is between the single signal deflections of the succession and if the signal deflections belonging to each other are respectively within a duration of 50 ms. Every arbitrary combination of the verifications in every arbitrary sequence is principally conceivable.

LIST OF REFERENCE SIGNS