DE102005038678A1 - Detection system, as well as this underlying detection method - Google Patents

Abstract

Acquisition system for recording a presence event within an observation area, with a field preparation facility for the generation and emission of a modulated alternating field in a field emission zone, and one on the observation area aligned signal pickup device for detecting field electrical Actions, wherein the detection system is configured such that over the signal tapping device signal events can be tapped off the in the area of the field emission zone into an object to be observed, in particular a user coupled and over the object, in particular the user in the observation area be coupled.

Description

The Invention is directed to a detection system in particular for Initialization or coordination of circuit processes in the Connection with the presence and possibly the movement of limbs in an observation area, wherein the detection per se is based on field-electrical interaction principles, in particular under detection of field-electrical relevant effects of the object in the observation area. The invention is directed continues to be realized on the basis of the detection system Detection method.

capacitive Proximity sensors can as entrapment and / or theft protection in doors, windows and motor vehicles as well as components of circuit devices application Find. Usually this oscillating circuits are provided. These resonant circuits include High voltage sections which are constructively designed such that over these changes the dielectric properties of the surrounding area are detected can. These high voltage sections can in the area of control surfaces be provided so that on the basis of determined changes in said dielectric Properties of the environment of the control surfaces Switching signals generated can be.

Of the Invention has for its object to provide solutions that make it possible detection operations of the object, in particular of limbs for initialization or Coordination of circuit processes in terms of the informational value of the detected presence events enable improved way.

These The object is achieved by, by a detection system for detecting a presence event within a Observation area, with a field preparation device for generating and radiating a modulated alternating field into a field emission zone, and a signal pickup device aligned with the observation area for detecting field electrical effects, wherein the detection system configured so that over the signal tapping device signal events can be tapped off the in the area of the field emission zone into an object to be observed, in particular a user coupled and over the object, in particular the user are fed into the observation area.

Thereby is it possible in an advantageous manner reliable and with high signal sharpness the presence, and in particular the movement of a user, or the limbs of the same in the observation area.

The Detection device is according to a particular preferred embodiment the invention designed such that this multiple Abgriffsschnittstellen for tapping the signal events, based on properties the tapped at the respective tapping signals to each other an evaluation result is obtained. This makes it possible, the Position of an object, in particular a person, or their limbs in relation to determine the detection devices.

When Property of the signal events, in particular the signal intensity and / or also runtime effects are evaluated. It is possible the Measurement results, e.g. intensities and / or phase information to evaluate a fault-optimized evaluation system and any Largely compensate for inaccuracies. It is possible the current one Determine location errors and, where appropriate, the admissibility depends on the input to keep. The result of evaluation is thus preferably a result won, the indicative is for the relative position of the object with respect to the detection devices. For example, it is possible the presence a driver in front of a vehicle steering wheel, and its distance from the steering wheel to to capture. Based on this information, it can be determined, for example an ignition an airbag still allowed is, or if no ignition, or possibly only a partial ignition can be made.

Based the evaluation result can also be a switching coordination. This can be realized so that certain movement characteristics be recognized and interpreted as a switching command.

According to one Another aspect of the present invention makes it possible to have several Field preparation devices provide these field preparation devices offset in time can be controlled such that via this approach an assignment the detection events for field emissions of certain field preparation facilities can be used. Alternatively, or in combination with this measure it also possible to control the field preparation devices modulated such that each of these specific signal patterns the emitted alternating field impress.

The field preparation devices can be arranged and configured such that they generate spatially different field emission zones. The information about it, by which Feldberei processing device, a signal event is coupled into the object and tapped at the detection means can be processed as Schaltablaufablaufsrelevante information. In a motor vehicle, for example, it can be determined by this concept from which seat a certain input operation is initiated. For example, input operations reserved exclusively for the driver can only be initiated by the driver. The detection devices can be arranged in association with a graphically animated input surface, in particular a touch-screen-like display surface. Depending on which person approaches the display surface with their hand, specific menu areas can be generated. It is possible to provide further coupling systems, for example, user-side leading identification signal generator, which also cause a signal input into the signal pickup device. The activation of this user-side leading to identification transmitter can be done by the provided by the field preparation device transmission event. The signal provided by the field preparation device can be loaded with a specific information content. This information content can be made dependent on the input treatment of the user, or certain other dialogue criteria. Based on a user-specific identifier, it is possible to perform an encrypted data transfer.

The inventive detection system can Part of a user button of an electrical appliance in particular household appliance e.g. a dishwasher, a washing machine or a stove. That's the way it is possible, the To arrange and align field emission zones so that only persons with a certain height in the Immerse the field emission zone and here the modulated base field can take up.

The inventive detection system can Part of a safety circuit forming by which of Operation of safety-relevant structures are monitored and coordinated can. It is possible, to realize the system such that the field emission zone itself is located in the area of a switch-on switch, so that this Switch actuated User through the coupled into this alternating field with a quasi-synthetic aura is equipped. Any approximations at risk-relevant Areas can This can be detected particularly effective.

The Detection system can according to a special Aspect of the invention form part of an airbag control circuit. The field emission zone and the observation area are arranged in such a way that a field bypass caused by the object is a logical content can be assigned.

a Sensor approximating People can with their natural capacity change electrical (alternating) fields and measurable. The measure of this change can then as an approximation interpreted and over Interfaces evaluated by circuitry. This is special with automatically closing Devices of particular importance, as these powered are and pinching a person to significant injuries can lead. Due to physical circumstances, the changes capacity Such a sensor system but also by external influences, not from an approaching Person come from. This can be changes weather conditions (humidity, rain, snow, hail, drought) be that change the dielectric or dissipative areas (Metal, electric fences, Hydrants, puddles of water Etc.). In addition, doors, flaps, Sunroofs, Ceilings that are operated electrically or hydraulically their positional changes in position often have the capacity of a acted upon sensor system. about Position sensors and / or timed matrices can compensate for such a change, however, the effort is considerable. task The invention is therefore a sensor system on a capacitive basis to provide, which works largely weather and Stelliergangsunabhängig and only the approach detected by persons. The invention is intended both the position as well as the direction of possible in hazardous or hazardous areas penetrating limbs determine and evaluate. In addition to a (for economic reasons) low Circuit complexity is a high reliability of such Sensor system be obtained. External environmental or setting-related influences should certainly be disregarded by the invention and no Influence on the intended operation of proximity sensors have more.

Instead of a passive capacitive proximity system, which works by detuning of oscillator frequencies with additional (eg limbs) introduced capacities, the invention acts as an active system. In this case, an alternating electric field is impressed on a person approaching a detection area. This field acts like a synthetic aura on the whole body of man. If this now holds limbs such as arms, legs, hands, etc. in the vicinity of a sensor element, this can measure the strength of the impressed alternating field and thus reliably detect the presence of an approaching body part. Frequency generator, human and danger point thus form an AC circuit whose impedances are capacitively changed by the approaching person. The closer this comes to the generator and / or the danger point, the higher will be the level to be measured. The invention thus has the task to measure such a level and to determine the approximation. Of particular importance is that feeding to the skin of a human (or an animal) can also be capacitive, so that no direct contact with a frequency generator has to be made. It is also possible to apply data to the fed-in AC signal, which gives indications of the entry location and / or the current position of the person acting. In this case, the level-measuring sensor element has at least one measuring point. Advantageously, a plurality of measuring points can be mounted in a detection or danger or detection area. Of these, one or more measuring points can be designated as reference plates, so that the approach in a danger zone can be compared with the reference points and reliably evaluated (triangulation). An additional decoding circuit can supply the applied data from the signals of an evaluation unit. This makes it possible, for example, to differentiate several people who are at a different location (eg driver and front passenger of a car), if this is a danger point (eg closing window, sunroof, trunk lid, convertible top, sliding doors, etc.) during a dangerous Approach (open, close). Furthermore, the invention determines the speed of penetration, which can lead to a dynamic turn-off behavior of the setting process. An early detection of a sensor signal originating from limbs, eg from an invading hand, can be detected so early that it is possible to warn the person concerned. Only when further approaching a shutdown process can be initiated (emergency shutdown). Analogously, the invention can also be used (possibly simultaneously) for burglar alarms. The measuring points can each be designed as a separate circuit. It makes more sense, however, to interrogate the measuring points one after the other one by one and to supply the level measured to you to a common evaluation unit, which considerably simplifies the circuit complexity.

One Oscillator (any waveform possible) generates a frequency of, for example, 200 kHz with a voltage level for example, 10 volts. At the output of the oscillator is a Delivery area off conductive material (e.g., copper foil, graphitized plastics, Rubber, etc.), which is the signal generated by the generator as changing charge field maps. The other pole of the generator was switched to ground. Does a human come close to this? Field, so does his body the other area a capacitor and the AC voltage is transmitted to his body. The resulting losses are inventively negligible. approaches Now this human is a sensor element that is able To measure the level of the AC voltage, so this is weiterführender approach an ever higher level Show. Usefully, the invention converts the level into a DC voltage, so that it can be measured and evaluated. Leave it on the one hand adjust the sensitivity of the sensor system, the other is enough the detection of the frequency at the sensor element also as proof the presence of an acting person in a danger area. The sensor signal can be filtered and amplified fed to a converter be the level of either the RMS value (EMS) or the Can convert peak value into a DC voltage. Such components are available inexpensively. A downstream buffer amplifier allows the load-free scanning of the DC voltage corresponding to the level. A microcontroller with ADC and / or comparator can measure the voltage and / or turn on the comparator at an adjustable threshold. The sensor element, e.g. a sphere, a surface, a wire, etc., is over one Capacitor connected to the input of the sensor circuit.

Further Details and features of the invention will become apparent from the following Description in connection with the drawing. It shows:

1 a circuit diagram for illustrating the underlying the detection system according to the invention signal transmission principle;

2 a Schschaltungsskizze illustrating the detection system according to the invention with multiple Abgriffsschnittstellen;

3 a circuit diagram illustrating a variant with a variable with respect to their spatial position field emission zone (exciter field);

4 a schematic representation to illustrate the inventive concept in a system variant with two field emission zones and multiple Abgriffsschnittstellen;

5 a schematic diagram illustrating a realized on the basis of the inventive concept security system for hedging hazardous areas of a machine (saw here);

6 a sketch for illustrating a control panel in which input operations are extracted from location and / or movement information, this spatial and / or Bewegungsinforma tion based on the properties signals are detected, which are tapped at the spaced tap interface signals;

7 a sketch illustrating a particularly advantageous application of the detection system according to the invention in a household appliance;

8th a sketch illustrating an insert variant of the detection system according to the invention in a motor vehicle, wherein at least one Tiel the Abgriffsschnittstellen is integrated into a vehicle steering wheel.

According to the circuit 1 a (here passive) filter (parallel resonant circuit) is provided, as such, allows a sharp selection of the sensor signal and suppressed interference frequencies. Alternatively, an active filter is also possible. The amplifier serves to amplify the possibly strongly attenuated signal sufficiently.

2 shows an extended circuit. Several measuring points can be connected to the same input. The measurement points that are not required in each case are grounded by multiplexer-connected port outputs of the microcontroller, all of them except for the actual measuring point. Since the capacitors are now grounded, their capacitance must be taken into account in the filter circuit. Cyclically, measuring point for measuring point is then fed to the amplifier, the level to DC-DC converter, the comparator or AD converter via the buffer, measured and evaluated. One or more measuring points can serve as a reference point. This means that a differently strong feed into the human body can nevertheless lead to an exact position or direction determination, since it is always compared with reference points.

was applying data to the signal to be measured (e.g., ASK modulation), so can this as a change at the output of the level meter e.g. fed to a comparator, which in turn restores the data and feeds it to an evaluation unit. To sit for example, in a vehicle several people on their seats, thus it can be advantageously determined which person, for example engages in the safety gate of a motorized convertible top and is thus in danger of injury (which is common, e.g. by children). There is a generator unit under each seat attached the different data to this sitting person imprints (for example an "F" for driver, "B" for driver Passenger, "L" for left Back seat, "R" for right back seat etc.). These data appear at the output of the sensor (where they are in Normally not belong), it has thus been proven that a relevant and precisely identifiable Person in danger, which is e.g. be communicated to the driver may or may lead to a warning or interruption / shutdown of the setting process. This does not apply according to the invention only for motor vehicles.

From Of particular importance is the imprint of a data-modulated Signal on the human body, because it must be ensured that this imprint always takes place as soon as possible the possibility There is a human being with his limbs in a hazardous area can penetrate.

The special one execution of the signaler

The signal generator is a generator that can generate an AC signal. This can be one or more square, triangle, sine or trapezoidal frequencies, etc. Via a mixer this signal reaches the delivery area. Under certain circumstances, a level increase can be made by inductors or voltage transformers, if necessary. With the mixer, it is possible to impose data on this alternating voltage signal, whereby all known types of modulation can be used. However, care should be taken to ensure that the modulation of the data does not change the level significantly, so that an evaluation is not dependent on an imposed code sequence. If possible, the other end of the oscillator should be connected to a ground or to the negative pole of a battery. In the second case, it is also possible to carry the signal generator in the form of a check card or a key fob. This is useful, for example, for mobile people who constantly have to approach dangerous machine parts in order to remove workpieces, etc. With the help of buffers (shielddriver), it is possible to apply the emitted signal to additional electrodes and direct the signal in certain directions in a club shape ( 3 ).

If a human being enters this area of influence of such a signal lobe, the signals applied with data are imprinted on his body and distributed over the entire skin area (charge image). If this person now comes with their limbs to a sensor point or in the vicinity, the received level is measured and compared with that of a reference point. Thus, the approach can be reliably detected. Furthermore, it can be determined from which place the person was charged with the signal, since this carries corresponding data. For example, it is possible to provide seals such as are very common in vehicles, windows, etc., with a dispensing and shield surfaces. Also suitable are vehicle handles Fe, control elements, floor mats, vehicle seats, steering wheels, door handles, door and window frames etc. For windows in front of houses, it is possible to give the signal, for example, to the cellar grid. An approaching burglar would then pick up the signal and trigger an alarm when the window touches or when approaching. This alarm stops when a cat is approaching or raining, as no closed AC circuit can be established. An accommodation in a window frame is also possible. Such an encoder can also be derived from a microcontroller, which performs tasks in a control unit of a vehicle intended tasks when a free I / O pin is used as eg square wave output (internal PWM or software-controlled frequency high-low control). For more extensive (signal / spectrum) analysis, the generated signal may also be wobbled.

A first exemplary application

4 shows occupant protection in a motor vehicle. Below the driver and passenger seats are the feed sheets of the oscillators 1 and 2, which impress data-loaded signals, eg "F" for the driver, "B" for the front passenger, on the respective seat and on the person sitting on it. When closing a motor-driven sunroof, a sensor element mounted in its vicinity determines whether a data-loaded signal can be detected there. Thus, it can be determined with certainty whether the driver or the passenger during the closing process holds his hand close to closing edges, where a significant risk of injury may exist. If the vehicle is at a standstill, there is the possibility that people can intervene in a closing sunroof from outside. An approaching person accepts this signal capacitively and passes it on engagement in the sunroof on the sensor point where it is detected and the sunroof stops and simultaneously triggers an alarm (anti-theft). This is particularly advantageous for motorized convertible tops, which are to be opened increasingly remote controlled. Since it can not be ascertained whether the driver is able to observe his top during an opening or closing operation, the sensor must take care that persons approaching from outside or inside the shearing top linkage can not be endangered. Therefore, an alternating field is impressed on an approaching person in the manner described above, which can be detected on the linkage of the convertible top when approaching it, which leads to the stopping of the setting process (and to trigger an alarm). If the hood is open, the same circuit works as theft protection. Here, for example, the sealing elements could be acted upon by an oscillator signal. Engaging the vehicle over the gasket imparts the AC signal to the person. If it now comes close to a sensor point, eg on the center console, this is detected and the alarm is triggered (theft protection with the convertible open). Accordingly, electrically operated windows, doors or flaps can be secured by the invention.

Another exemplary embodiment

In a table saw ( 5 ) emits an oscillator signal horizontally to the edge of the table in the room. An approaching person picks up this signal. When approaching the running saw blade this can be determined and the saw blade pulled away, for example, by hand in a protection zone and / or stopped and / or covered by a flap, so that in no case a violation of the hand is possible. A reference point attached to the table saw checks a level and can detect the degree of impact on the person. This is necessary so that different body dimensions and physiques do not lead to different shutdown results (exact triangulation possible). By additionally mounted on the side edges of a table saw according to the invention signal generator and helpers can be acted upon with signals and are therefore also protected against injury by the saw blade. Here, the shutdown could be done earlier, since helpers usually have less expertise than the operator of a machine.

Another one example

Four Sensor measuring points are near one Motor vehicle steering wheel or attached to this. Under the driver's seat there is a generator with a signal-emitting foil. is If a driver sits in this seat, his body will be dubbed Signal applied, which also exists on his limbs is. If this now reaches the steering wheel, it can be determined where He does this and whether this happens with one or both hands (or knees are used). When taking away a hand, e.g. when operating switching elements, another sensor point (by multiplexity simply switchable) notice this and, for example, the direction Calculate the hand to activate switch at the expected target point or to illuminate controls.

Since measuring points are moved on the steering wheel when steering, it is also possible with the invention, for example, with an additional reference feed signal to determine the steering angle ( 8th ). Also it is possible to determine if about the front passenger grabs the steering wheel. For this purpose, generators are housed with signal-emitting foils in the driver and front-passenger seats, which are beauschlagt with different data. When approaching the steering wheel sensor electrodes, the data is decoded and may be assigned to the driver or passenger.

exemplary Application of the invention for touch screens

The Touch screens receive one sensor point at each of the four corners in the manner described. A touch screen is located For example, in a motor vehicle whose driver and / or passenger seat provided with a data modulated generator and a delivery foil are. If a person is seated in this seat, they may approach the touch screen and the direction of its outstretched Index finger can be determined so that under the index finger a menu will appear can. The driver needs during the So do not go to a menu the touch screen, but it always arises "safe under his Fingers ", as known is, from which direction the finger comes and where he wants, and although already before the actual touch of the touch screen. By the distinction between driver and front passenger can come up with different menus, for example for vehicle operation or for setting the ambience, such as Light, heating, seat etc. for the respective person. This is advantageous with the invention just possible and was previously a domain The image processing and could only be solved very expensive.

exemplary Simulation of a keyboard matrix

On a surface of non-conductive material, such as plastic, keypads may be printed ( 6 ). At the corners of the surface measuring points according to the invention are housed. An operator charged with the encoder signal can now approach with the finger of a (virtual) "key" and thereby trigger a predetermined switching function. Sliders or sliders can also be realized in one or two or three dimensions. If the encoder signal is emitted obliquely upward above such an area, it would be possible to implement, for example, a washing machine operation, for example. Smaller children can not be affected by the transducer signal if they are located below the feed lobe (due to their size) (easy infant protection) ( 7 ). In addition, switching operations can also be prevented if the operator does not follow a mobile signal transmitter with a corresponding authorization code.

Exemplary gesture control

The dynamic operation of the invention allows the registration and Evaluation of motion sequences. these can come from signaled people or machine parts. movements the hands and / or fingers, ie gestures also be evaluated according to the invention.

use the invention as a signer

There the position of limbs spatial is detected, it is possible with the index finger to paint in the air. This can be the Decode the evaluation circuit and feed it to a processing system. So can e.g. gestures, make radios louder and quieter, or and be turned off.

Application in airplanes

Under Each seat contains a data-modulated oscillator with delivery foil. actuated If a passenger calls a call button, the stewardess becomes the seat number (and possibly the name) displayed. She can then take the passenger with her to address the name. The actual call system remains untouched. Only the approach is detected and detected. Attacks or shows a passenger in Direction of his reading lamp, it is turned on or off. In this case, a switch can be dispensed with, since the approach is safe is recognized and also the person is identified.

Example: tracked headrest

In a headrest There are four measuring points of the invention, while the seat with the previously described oscillator and the release film is provided. sits a human on this slide, he picks up the signal and gives it over move his head to the sensor points. These raise the headrest the right height one and the right distance to a whiplash in a rear-end collision to avoid. If the person moves while driving, the headrest be safely tracked. Children are found to be below the headrest, which may be lead to airbag shutdown could. In this way, a persons size dependent seat occupancy is in one Motor vehicle (aircraft, train, etc.) feasible, with the Seat belts in the sensor system can be integrated with their Use to prove.

Transmission of external data

The mixer of a sensor according to the invention can also be supplied with external data, for example, come from sensors.

At the sew on At least one measuring point, these data are decoded and a Evaluation device supplied. In addition to environmental data (temperature, speed, pressure, weight etc.) could also biological data of the person acting (EEG, ECG, respiration, Pulse, etc.) become.

Connection of different data decoder

Parallel for proper use of the invention can be applied to these additional receiving and data decoding devices turn on to before or during an approach at the same time also to transmit data.

Position-speed and direction determination

By repeated measurements of a rapprochement process let yourself compared to the previous measurement next to the position signaled limbs also their approximation Speed and direction determine as well as the probable destination of the movement. Mechatronically controlled feeding systems can with this information e.g. work faster. Usually such start only when, at the destination of the movement, e.g. a button pressed or e.g. a light barrier is interrupted.

Adjustable detection direction

By meaningful shielding and / or buffering (shield) of the receiving electrodes Is it possible, this for a determinable detection range / angle mechanical and / or to align electronically.

Claims (15)

Detection system, for recording a presence event within an observation area, with a field preparation facility for the generation and emission of a modulated alternating field in a field emission zone, and one on the observation area aligned signal pickup device for detecting field electrical Actions, wherein the detection system is configured such that over the signal tapping device signal events can be tapped off the in the area of the field emission zone into an object to be observed, in particular a user coupled and over the object, in particular the user in the observation area be coupled. Detection system according to claim 1, characterized the detection device has a plurality of tap interfaces for Has taps of the signal events, and that based on properties the tapped at the respective tapping signals to each other an evaluation result is obtained. Detection system according to claim 2, characterized in that that evaluated as a property of the signal events, the signal intensity becomes. Detection system according to claim 2, characterized in that that runtime effects are evaluated as a property. Detection system according to claim 2, characterized in that that as a result of evaluation a result is obtained, the indicative is for the relative position of the object with respect to the detection devices. Detection system according to at least one of claims 1 to 5, characterized in that based on the evaluation result a switching coordination takes place. Detection system according to at least one of claims 1 to 6, characterized in that a plurality of field preparation devices are provided. Detection system according to at least one of claims 1 to 7, characterized in that the field preparation devices be controlled with a time delay. Detection system according to at least one of claims 1 to 8, characterized in that the field preparation devices generate specific signal patterns. Detection system according to at least one of claims 1 to 9, characterized in that the field preparation devices locally different Generate field emission zones. Detection system according to at least one of claims 1 to 10, characterized in that the information about it, by which field preparation device coupled a signal event in the object is processed as switching sequence relevant information. Detection system according to at least one of claims 1 to 11, characterized in that the detection system component a user button forms. (Car, washing machine ...) Detection system according to at least one of claims 1 to 11, characterized in that the detection system is part of a Si safety circuit. Detection system according to at least one of claims 1 to 11, characterized in that the detection system component an airbag control circuit forms. Detection system according to at least one of claims 1 to 14, characterized in that the field emission zone and the observation area are arranged such that one caused by the object Field bypass logical content can be assigned.