Patent Description:
<CIT> relates to a motor vehicle comprising a fender provided at the front and the rear and at least one sensor device, which has a capacitively operating sensor. The sensor device has an associated control device for collision detection, wherein the sensor is arranged on a fender. The sensor is formed as a surface sensor which extends over at least half the width of the fender. The control device is able to determine information resulting from a collision with an object by using the capacitance of the sensor, which changes as a result of collision-induced deformation of the sensor.

<CIT> describes an impact detector for detecting and evaluating an impact and generating an output signal to deploy a pedestrian protection system on a motor vehicle The impact detector includes a sensor arrangement to be mounted at the front of the vehicle to detect an impact. An evaluator is provided to evaluate the output of the sensor and to generate an output signal when a predetermined threshold is exceeded, so that the pedestrian protection system is not actuated by an impact with a very light object. In addition, a chassis-mounted accelerometer is provided to provide a signal indicative of the total deceleration applied to the vehicle. An inhibitor is provided to inhibit generation of the signal that actuates the pedestrian protection system, if the output signal from the accelerometer exceeds a predetermined threshold.

<CIT> discloses a collision discriminating device for a vehicle comprising a collision detecting means for detecting the collision on the basis of the deformation of a collided surface of vehicle. The collision detecting means is formed by an electrostatic capacity-type collision detecting sensor part formed by counter electrodes mounted on the collision surface at specific intervals and a dielectric formed by an elastic member inserted between the counter electrodes. <CIT> discloses an impact sensing device. A sealed chamber, filled with a pressure medium, is provided. At least one surface acoustic wave device is associated to said sealed chamber for sensing a pressure inside said pressure chamber. The sealed chamber is designed to be arranged in a vehicle at a location where an impact during a collision situation is to be sensed. The surface acoustic wave device includes at least one surface acoustic wave resonator and an antenna for remotely communicating with a control unit arranged within said vehicle.

<CIT> relates to a pedestrian protection system for a vehicle. The protection system having at least one impact-detecting sensor and a deformable element that are arranged between a cross-member and a bumper cover of the vehicle. A control unit is provided that analyses the signals of the at least one sensor. In order to reduce the amount of space required, the deformable element is designed as a deformable member that has a cavity in which the at least one sensor is arranged and the at least one sensor detects changes in an electromagnetic field in the cavity.

<CIT> shows a multidimensional force sensor with a multibeam structure for measuring displacement of one or more response elements to detect multiple components of applied force. The displacement of the response element is detected with a variety of sensing methods including capacitive and piezoresistive sensing.

It is therefore an object of the present invention to an impact detection and protection which has redundancy, provides an impact recognition, enables a diagnosis and allows a simplified integration in a vehicle.

The above object is achieved by an impact detection and protection system for a vehicle which comprises the features of claim <NUM>.

According to an inventive embodiment an impact detection and protection system defines an axis. Especially a sensor is used to provide some protection for a pedestrian in case an impact happens. The axis is essentially parallel to or aligned with a front face of a vehicle. The sensor of impact detection and protection system has at least one sensor element of a first type, which is oriented along the axis of the sensor. Additionally, the sensor has a plurality of sensor elements of a second type, which are oriented and uniformly distributed along the axis of the sensor. The advantage of the two different sensor types is a redundancy, wherein both sensor types are integrated in one sensor. Furthermore, the sensor allows the determination of location of the impact at the front side of the vehicle. The impact location can be achieved by the at least one sensor element of the first type and/or the plurality of sensor elements of the second type.

According to the embodiment of the invention the at least one sensor element of the first type is a capacitive sensor and the plurality of sensor elements of the second type are piezoelectric sensor elements. According to an example, that is not part of the claimed invention, the at least one sensor element of the first type is a capacitive sensor and the plurality of sensor elements of the second type are accelerometers. According to a still further example, that is not part of the claimed invention, the at least one sensor element of the first type is a capacitive sensor and the plurality of sensor elements of the second type are force sensitive sensor elements. Moreover, the plurality of sensor elements of the second type can be as well a mixture above mentioned sensor elements of the second type.

According to one possible embodiment of the invention the sensor of impact detection and protection system comprises one single sensor element of the first type and the plurality of sensor elements of the second type. The plurality of sensor elements of the second type are oriented and are separated equally along the axis of the sensor. According to a further embodiment the plurality of sensor elements of the second type can separated unequally along the axis of the sensor. The axis of the sensor is essentially parallel to the orientation of the sensor element of the first type.

For the collection of signals from the at least one sensor element of the first type, the at least one sensor element is electrically connected by a wiring to a first amplifier. According to a preferred embodiment the sensor comprises one single capacitive sensor, which is connected to the first amplifier. The operating mode of the at least one capacitive sensor is that an impact causes a distance change of the two electrodes of the capacitive sensor. The change in distance of the electrodes results in a capacitive change, which is amplified and used for the verification of the impact.

According to one possible embodiment of the invention each of the plurality of sensor elements of the second type is electrically connected by a wiring to a second amplifier.

The sensor comprises for example eight sensor elements of the second type (piezoelectric sensor elements). The eight piezoelectric sensor elements are connected to eight channels of the second amplifier by an individual wiring.

According to another possible embodiment of the invention two of the plurality of sensor elements of the second type are commonly connected by a wiring to the second amplifier. Consequently, the second amplifier has four channels to which the eight piezoelectric sensor elements are connected in pairs.

According to an example, that is not part of the claimed invention, of the impact detection and protection system, the pairing of the eight piezoelectric sensor elements is such that the first and the third piezoelectric sensor elements are connected to the first channel, the second and the fifth piezoelectric sensor elements are connected to the second channel, the fourth and the seventh piezoelectric sensor elements are connected to the third channel and the sixth and the eighth piezoelectric sensor elements are connected to the forth channel. The advantage of this example is the minimum wiring for the capacitive sensor element and a location resolution between the left, the right and the middle of the sensor.

According to a further example, that is not part of the claimed invention, of the impact detection and protection system, the pairing of the eight piezoelectric sensor elements is such that the first and the eighth piezo electric sensor elements are connected to the first channel, the second and the seventh piezoelectric sensor elements are connected to the second channel, the third and the sixth piezoelectric sensor elements are connected to the third channel and the fourth and the fifth piezoelectric sensor elements are connected to the fourth channel. The advantage of this example is the minimum wiring for the capacitive sensor element and symmetric areas on the left and the right of the sensor.

According to a further embodiment of impact detection and protection system the amplifier for the one capacitive sensor element and the amplifier for the eight piezoelectric sensor elements are combined in one printed circuit board. The printed circuit board is provided at one end of the sensor. The advantage of this arrangement is a simplification of the wiring to the amplifier for the capacitive sensor element and the amplifier for piezoelectric sensor elements. As mentioned above the arrangement of the piezoelectric sensor elements provides a location resolution of the location of impact. According to a further example, that is not part of the claimed invention, all the piezoelectric sensor elements of the sensor can be connected to ground potential.

In order to use the inventive sensor in the field, a carrier for the sensor is provided. According to the embodiment, the sensor is enclosed within the carrier. The carrier is deformable by an impacting object (for example a pedestrian). The impact causes a deformation and an electrical signal from the at least one sensor element of the first type and the plurality of sensor elements of the second type.

According to the embodiment of the invention of the impact detection and protection system the carrier has a first foam element and a second foam element. The first foam element and the second foam element enclose the sensor and are in mechanical contact with the sensor. At least the first foam element, being essentially perpendicular to the direction of driving, is deformable by the impact of the object. The impact causes a deformation and an electrical signal from the at least one sensor element of the first type and the plurality of sensor elements of the second type. The sensor elements of the second type provide information about the location of the impact.

According to the embodiment of the invention a plurality of dome shaped cavities are formed in the first foam element. Each of the dome shaped cavities defines an apex and is open to the second foam element. One single sensor element, which is a piezoelectric sensor element, of the plurality of sensor elements of the second type is attached to the apex. The at least one sensor element of the first type of the sensor is supported by the second foam element of the carrier. In the embodiment as discussed here the domes are oriented towards the direction of impact. According to another embodiment, the domes can be oriented with the apex pointing toward a structural element (cross member) of the vehicle.

According to one possible embodiment of the invention the sensor, configured for use and mounting in a vehicle, comprises the carrier with the enclosed sensor, which is surrounded by a sealing. The sealing has at one end a welded end and at an opposite end the sealing is attached to an inner wall of a housing (end cap). According to a preferred embodiment the sealing can be attached to the inner wall of the housing with a glue. The housing is closed at one end by the sealing, which is attached to the inner wall of the housing, and at the other end by a connector.

A printed circuit board is placed inside the housing. The first amplifier and the second amplifier are realized on the printed circuit board. The at least one sensor element of the first type is connected by a wiring to the first amplifier and the plurality of sensor elements of the second type are connected by a wiring to the second amplifier.

According to a preferred embodiment of impact detection and protection system the second amplifier has four channels and the wiring for the plurality of sensor elements of the second type is such that the plurality of sensor elements of the second type are grouped and connected to the four channels. The first amplifier and the second amplifier are connected to a digital interface, which is a digital, two-wire interface for sensors in vehicle electronics. According to an example, that is not part of the claimed invention, the first amplifier, the second amplifier and the digital interface are realized by an ASIC.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not necessarily restrictive of the present disclosure. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate subject matter of the disclosure. Together, the descriptions and the drawings serve to explain the principles of the disclosure. The mentioned numbers of the sensor elements of the first type and the sensor elements of the second type are utilised to explain the invention and should not be regarded as a limiting factor of the invention.

Same reference numerals refer to same elements or elements of similar function throughout the various figures. Furthermore, only reference numerals necessary for the description of the respective figure are shown in the figures. The shown embodiments represent only examples of how the invention can be carried out. This should not be regarded as a limitation of the invention.

<FIG> shows a sensor <NUM> for an impact detection and protection system according to the prior art. The sensor <NUM> comprises a plurality of sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>M of a first type, arranged along an axis A of the sensor <NUM>. The sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>M of the first type are capacitive sensor elements. In the embodiment shown here eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> are arranged along an axis A of the sensor <NUM>. The eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM> are connected by a wiring <NUM> so that the first sensor element <NUM>, and the third sensor element <NUM><NUM>, the second sensor element <NUM><NUM> and the fifth sensor element <NUM><NUM>, the forth sensor element <NUM><NUM> and the seventh sensor element <NUM><NUM>, and the sixth sensor element <NUM><NUM> and the eighth sensor element <NUM> are connected electronically. This results in five different zones <NUM><NUM>, <NUM><NUM>,. , <NUM><NUM> which provide five different and distinct areas of impact. With the wiring <NUM> mentioned above the sensor <NUM> defines an effective range <NUM> along the axis A of the sensor <NUM> with a redundancy effect. The redundancy effect means that always two sensor elements <NUM><NUM>, <NUM><NUM>,. , <NUM><NUM> per zone <NUM><NUM>, <NUM><NUM>,. , <NUM><NUM> are affected at the occurrence of an impact.

The <FIG> show various embodiments of a sensor <NUM> for an impact detection and protection system. It is to be understood that the number of the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>M of a first type and the number of the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of a second type mentioned in the specification below are exemplary and explanatory only and are not necessarily restrictive of the invention as claimed. <FIG> are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description, serve to explain the principles of the invention.

<FIG> shows a sensor <NUM> for an impact detection and protection system with two different types of sensor elements according to one embodiment of the invention. According the embodiment shown here, the sensor <NUM> comprises eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM> of a first type and nine sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of a second type, both of which are oriented and uniformly distributed along the axis A of the sensor <NUM>. The eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the first type and the nine sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are arranged such that each sensor element <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the first type is located between two sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type. In the embodiment shown here the sensor elements <NUM><NUM>, <NUM><NUM>,. , <NUM><NUM> of the first type are capacitive sensor elements and the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are piezoelectric sensor elements. Both the capacitive sensor elements and the piezoelectric sensor elements are distributed homogeneously and uniformly along the axis A of the sensor <NUM>. The effective range <NUM> stretches from the first sensor element <NUM><NUM> of the second type to the last sensor element <NUM><NUM> of the second type. For sensing an impact at least one sensor element <NUM><NUM>, <NUM><NUM>,. , <NUM><NUM> of the first type and one neighbouring sensor element <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type must sense and be affected.

<FIG> shows a further embodiment of a sensor <NUM> for an impact detection and protection system with one sensor element <NUM>, of a first type and eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of a second type. The sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are arranged along the axis A of the sensor <NUM>. The sensor element <NUM><NUM> of the first type is a capacitive sensor element and electrically connected by a wiring <NUM> to an amplifier <NUM>. The amplifier <NUM> amplifies a signal (change of capacity due to an impact) from the capacitive sensor element. The eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are piezoelectric sensor elements, which are electrically connected by a wiring <NUM> to an amplifier <NUM>. Consequently, the amplifier <NUM> receives eight channels <NUM>. The amplifier <NUM> amplifies a signal (change of electric charge due to an impact) from each piezoelectric sensor element. In case of an impact the eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type provide a spatial resolution with regard to the location of impact.

<FIG> shows another embodiment of a sensor <NUM> for an impact detection and protection system with one sensor element <NUM>, of a first type and eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of a second type. The sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are arranged along the axis A of the sensor <NUM>. The sensor element <NUM><NUM> of the first type is a capacitive sensor element and the eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are piezoelectric sensor elements. The eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are electrically connected by a wiring <NUM> to an amplifier <NUM>. The amplifier <NUM> has four channels <NUM>. The wiring <NUM> (grouping) is such that the first sensor element <NUM>, and the third sensor element <NUM><NUM> are connected to the first channel <NUM>, the second sensor element <NUM><NUM> and the fifth sensor element <NUM><NUM> are connected to the second channel <NUM>, the fourth sensor element <NUM><NUM> and the seventh sensor element <NUM><NUM> are connected to the third channel <NUM> and the sixth sensor element <NUM> and eighth sensor element <NUM> are connected to the fourth channel <NUM>. The amplifier <NUM> amplifies a signal (change of electric charge due to an impact) from each piezoelectric sensor element. The embodiment shown here has the advantage of a reduced wiring <NUM>. In case of an impact the eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM> of the second type provide a location resolution (left, right or middle of the sensor <NUM>) with regard to the location of impact.

<FIG> shows another embodiment of a sensor <NUM> for an impact detection and protection system which provides location detection of an impact by a variant of the redundancy. The basic construction of the sensor <NUM> is the same as shown in <FIG>. The difference is in the wiring <NUM>. The eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type are electrically connected by the wiring <NUM> to the amplifier <NUM>. The amplifier <NUM> has four channels <NUM>. The wiring <NUM> (grouping) is such that the first sensor element <NUM><NUM> and the eighth sensor element <NUM> are connected to the first channel <NUM>, the second sensor element <NUM><NUM> and the seventh sensor element <NUM><NUM> are connected to the second channel <NUM>, the third sensor element <NUM><NUM> and the sixth sensor element <NUM><NUM> are connected to the third channel <NUM> and the fourth sensor element <NUM><NUM> and the fifth sensor element <NUM><NUM> are connected to the fourth channel <NUM>. The amplifier <NUM> amplifies a signal (change of electric charge due to an impact) from each piezoelectric sensor element. The embodiment shown here has the advantage of a reduced wiring <NUM>. In case of an impact the eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type provide a location resolution with regard to the location of impact. There is no possibility to discriminate between a left area <NUM> and a right area <NUM> of the sensor <NUM>.

<FIG> shows an embodiment of the sensor <NUM> for an impact detection and protection system which is similar to the embodiment of <FIG>. The embodiment shown here differs from the embodiment of <FIG> in that the amplifier <NUM> for the capacitive sensor element <NUM><NUM> and the amplifier <NUM> for piezoelectric sensor elements <NUM><NUM> to <NUM><NUM> are combined in one printed circuit board <NUM> (see <FIG> and <FIG>). The printed circuit board <NUM> (side mounted electronics) is provided at one end of the sensor <NUM>. This arrangement simplifies the wiring <NUM> to the amplifier <NUM> for the capacitive sensor element <NUM><NUM> and the amplifier <NUM> for piezoelectric sensor elements <NUM><NUM> to <NUM><NUM>. As known from the embodiment of <FIG> the amplifier <NUM> for piezoelectric sensor elements has <NUM> channels.

<FIG> shows a variant of the embodiment of the sensor <NUM> for an impact detection and protection system as shown in <FIG>. Each of the eight sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM><NUM> of the second type (piezoelectric sensor elements) is provided with a ground <NUM>P. The ground <NUM>P of the first, second and third sensor element <NUM><NUM>, <NUM><NUM>, and <NUM><NUM> of the second type is connected to a first ground <NUM><NUM>. The ground <NUM>P of the fourth, fifth, sixth, seventh and eighth sensor element <NUM><NUM>, <NUM><NUM>, <NUM><NUM>, <NUM><NUM> and <NUM><NUM> of the second type is connected to a second ground <NUM><NUM>. The first ground <NUM>, and the second ground <NUM><NUM> are connected to the amplifier <NUM> for piezoelectric sensor elements.

<FIG> shows a schematic view of a carrier <NUM> for the sensor <NUM>. The sensor <NUM> is sandwiched between a first foam element <NUM> and a second foam element <NUM>. The first foam element <NUM> and the second foam element <NUM> are arranged such that the sensor <NUM> is completely enclosed within the first foam element <NUM> and the second foam element. At least the second foam element <NUM> has a flat outline for mechanical integration. For example, the carrier <NUM> is mounted with the second foam element <NUM> to a structural element <NUM> of a vehicle (not shown). The first foam element <NUM> faces into a driving direction D of the vehicle.

<FIG> show various embodiments of the carrier <NUM> for the sensor <NUM> taken along the section B-B of <FIG>. The sensor <NUM> is completely enclosed by the first foam element <NUM> and the second foam element <NUM>. The first foam element <NUM> of the carrier <NUM> shown in <FIG> has a flat surface, pointing in the driving direction D (see <FIG>). The first foam element <NUM> of the carrier <NUM> shown in <FIG> has a curved surface, pointing in the driving direction D (see <FIG>). It is to be understood that the design of the surface, pointing in the driving direction D, is not limited to the structures shown in <FIG>. The variation of the design of carrier <NUM> depends on the size and the height of the sensor <NUM> to be enclosed.

<FIG> shows a partial view of the sensor <NUM> layered between a first foam element <NUM> and a second foam element <NUM> of the carrier <NUM>. As mentioned above, the sensor <NUM> comprises at least one the sensor element <NUM><NUM>, <NUM><NUM>,. ,<NUM>M of a first type (here not shown) and a plurality of sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of a second type (here not shown). The sensor <NUM> is sandwiched between the first foam element <NUM> and the second foam element <NUM>.

<FIG> shows a partial cross-sectional view of an embodiment of the formation of the carrier, which houses the piezoelectric sensor elements and the capacitive sensor element. The first foam element <NUM> has a plurality of dome shaped cavities <NUM>, wherein the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of the second type (piezoelectric sensor elements) are placed in the apex <NUM> of each dome shaped cavity <NUM>. The wiring <NUM> for the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of the second type are as well arranged between the first foam element <NUM> and the second foam element <NUM>. A single sensor element <NUM><NUM> of the first type (capacitive sensor element) is placed as well between the first foam element <NUM> and the second foam element <NUM>.

<FIG> shows an enlarged view of the placement of a piezoelectric sensor element (sensor elements <NUM><NUM>, <NUM><NUM>,. , <NUM>O of the second type) within the carrier <NUM>. The sensor element <NUM><NUM>, of the second type is placed in the apex <NUM> of the not deformed dome shaped cavity <NUM>. The deformed state, due to a collision, is shown in <FIG>. A collision of the vehicle (not shown) causes the not deformed dome shaped cavity <NUM> to be transferred to a deformed dome shaped cavity <NUM>. The deformed dome shaped cavity <NUM> causes a deformation of the piezoelectric sensor element (sensor element <NUM><NUM> of the second type) within the deformed dome shaped cavity <NUM>. The deformation causes a voltage signal in the piezoelectric sensor element which is sensed by the amplifier <NUM> (see <FIG>) for the piezoelectric sensor element.

<FIG> shows a schematic, partial view of the arrangement of the sensor elements <NUM><NUM> and <NUM><NUM> of the first type (capacitive sensor elements; electrodes) and of the sensor element <NUM><NUM> of the second type (piezoelectric sensor element). The piezoelectric sensor element is placed in the apex <NUM> of the dome shaped cavity <NUM>. Another embodiment of the arrangement of the sensor elements <NUM><NUM> and <NUM><NUM> of the first type (capacitive sensor elements, electrodes) and of the sensor elements <NUM><NUM> of the second type (piezoelectric sensor element) is shown in <FIG>. Here the piezoelectric sensor element is placed in the apex <NUM> of the dome shaped cavity <NUM>. The sensor elements <NUM><NUM> and <NUM><NUM> of the first type (capacitive sensor elements, electrodes) are covered by a sealing layer <NUM>.

<FIG> shows an embodiment of the arrangement of at least one sensor element <NUM><NUM> of the first type (capacitive sensor element) inside the carrier <NUM>. The sensor element <NUM><NUM> of the first type is arranged in an undulating manner between the first foam element <NUM> and the second foam element <NUM>. An object <NUM> deforming at least the first foam element <NUM> in the impact direction DI causes a mechanical strain on the at least one sensor element <NUM><NUM> of the first type.

<FIG> shows the effect of a collision on the sensor element <NUM><NUM> of the first type (capacitive sensor element) in the carrier <NUM> (see for example <FIG>). The sensor element <NUM><NUM> of the first type is provided in a not undulating manner. An impact of an object <NUM> (see <FIG>) causes a strained sensor element 3D, of the first type. The strain might cause a rupture of the strained sensor element 3D, of the first type, which results in a malfunction of the sensor <NUM>. The effect of a collision on an undulated sensor element <NUM><NUM> of the first type (capacitive sensor element) according to the arrangement shown in the embodiment of <FIG> is shown in <FIG>. A collision here causes less strain on the sensor element <NUM><NUM> of the first type than in the example of <FIG>.

<FIG> shows a schematic side view and <FIG> shows a schematic top view of the integration of the sensor <NUM> in a sensor device <NUM> which is ready to use in a vehicle (not shown). The sensor <NUM> is enclosed in a sealing <NUM>, which seals the sensor and the associated electronics (for example, sensor <NUM>) against the influence of humidity and/or dirt and provides an electromagnetic shielding for the electronics. The sensor <NUM> is connected by the required wiring <NUM> to a printed circuit board <NUM>. The printed circuit board <NUM> encompasses the amplifier <NUM> for capacitive sensor elements (not shown here) and the amplifier <NUM> for piezoelectric sensor elements (not shown here). More precisely, the amplifiers <NUM> and <NUM> are realised by an ASIC <NUM> on the printed circuit board <NUM>. The printed circuit board <NUM> is enclosed in a housing <NUM>, which is closed at one end by a connector <NUM> and on the opposite end by the sensor <NUM>. A pressure equalizing system <NUM> is provided in order to keep the pressure inside the housing <NUM> approximately at a constant level. The connector <NUM> has connector pins <NUM> which provide an electrical connection to a control system (not shown) of the vehicle. The carrier <NUM> with the enclosed sensor <NUM> is surrounded by a sealing <NUM>. At one end the sealing is closed by a welded end <NUM> and at an opposite end the sealing <NUM> is attached to an inner wall <NUM> of the housing <NUM>.

<FIG> is an enlarged view of the area marked with a dashed circle <NUM> in <FIG>. The sensor <NUM> is fixed to the housing <NUM>. The sealing <NUM> is attached by one side to the sensor <NUM> and by the opposite side to the housing <NUM>. The attachment of the sealing <NUM> to the housing <NUM> is achieved with a glue <NUM>. In the embodiment shown here the sealing <NUM> is attached to an inner wall <NUM> of the housing <NUM>.

<FIG> shows a schematic view of the arrangement of the components of the sensor device <NUM>. The at least one sensor element <NUM><NUM>, <NUM><NUM>,. ,<NUM>M of a first type (capacitive sensor element) and the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of a second type (piezoelectric sensor elements) of the inventive sensor <NUM> are connected with a wiring <NUM> to the amplifier <NUM> for capacitive sensor elements and the amplifier <NUM> for piezoelectric sensor elements. Additionally, the at least one sensor element <NUM><NUM>, <NUM><NUM>,. ,<NUM>M of a first type and the sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of a second type are connected to a common ground <NUM>. The amplifier <NUM> for capacitive sensor elements and the amplifier <NUM> for piezoelectric sensor elements is realized on one chip, for example the ASIC <NUM>. Both amplifiers <NUM> and <NUM> are connected to a digital interface <NUM> which is a digital, two-wire interface <NUM> for sensors in vehicle electronics.

<FIG> shows a schematic view of the placement of the printed circuit board <NUM> (electronics) in relation to the sensor <NUM>. The printed circuit board <NUM> is placed in the middle of the sensor <NUM> so that the sensor <NUM> has a left sensor <NUM> and a right sensor 1R.

<FIG> shows an alternative embodiment of the inventive sensor <NUM>. The inventive sensor <NUM> comprises one sensor element <NUM>, of a first type and a plurality sensor elements <NUM><NUM>, <NUM><NUM>,. ,<NUM>O of a second type which are accelerometers. The accelerometers of the sensor <NUM> are placed close to the bumper (not shown) of the vehicle.

<FIG> shows a schematic view of a further embodiment of the placement of the printed circuit boards <NUM> (electronics) in relation to the inventive sensors <NUM>. Four individual sensors <NUM> are arranged symmetrically, wherein two of the four sensors <NUM> are connected to one printed circuit board <NUM>. Each of the two printed circuit boards <NUM> is connected to a respective digital interface <NUM>.

<FIG> shows a schematic view of an additional embodiment of the placement of the printed circuit board <NUM> (electronics) in relation to the inventive sensors <NUM>. Three individual sensors <NUM> are arranged such that the three sensors <NUM> are connected to a single common printed circuit board <NUM>. The printed circuit board <NUM> is connected to a digital interface <NUM>.

<FIG> shows a schematic view of an additional embodiment of the placement of printed circuit boards <NUM> (electronics) in relation to three individual inventive sensors <NUM>. Each individual sensor <NUM> is connected to a respective printed circuit board <NUM>. Each of the three printed circuit boards <NUM> is connected to a digital interface <NUM>.

Claim 1:
An impact detection and protection system for a vehicle: characterized by:
• a sensor (<NUM>);
• a carrier (<NUM>) for the sensor (<NUM>) having a first foam element (<NUM>) and a second foam element (<NUM>), wherein the first foam element (<NUM>) and the second foam element (<NUM>) sandwich, enclose and are in mechanical contact with the sensor (<NUM>) and the carrier (<NUM>) is mountable to a structural element (<NUM>) of the vehicle;
• wherein the sensor (<NUM>) comprises:
∘ at least one sensor element (<NUM><NUM>, <NUM><NUM>,...,<NUM>M) of a first type of the sensor (<NUM>) is oriented along the axis (A) of the sensor (<NUM>), wherein the at least one sensor element (<NUM><NUM>, <NUM><NUM>,..., <NUM>M) of the first type is a capacitive sensor;
∘ a plurality of sensor elements (<NUM><NUM>, <NUM><NUM>,...,<NUM>O) of a second type of the sensor (<NUM>) are oriented and distributed along the axis (A) of the sensor (<NUM>), wherein the plurality of sensor elements (<NUM><NUM>, <NUM><NUM>,..., <NUM>O) of the second type are piezoelectric sensor elements; and
• a plurality of dome shaped cavities (<NUM>) are formed in the first foam element (<NUM>) so that each of the dome shaped cavities (<NUM>) defines an apex (<NUM>) which is open to the second foam element (<NUM>), wherein one single piezoelectric sensor element (<NUM><NUM>, <NUM><NUM>,..., <NUM>O) of the plurality of sensor elements (<NUM><NUM>, <NUM><NUM>,...,<NUM>O) is attached to each apex (<NUM>).