DE102008017903A1 - Interface and control circuit for a sensor cluster for providing sensor data for vehicle applications - Google Patents

Abstract

The invention relates to an interface and control circuit (30, 32, 34) for a sensor cluster (10) for providing sensor data for vehicle applications (12, 14, 16), which has a multiplicity of sensors (18, 20, 22 , 24, 26, 28), of which one or more of the sensors have adjustable dynamic ranges, the interface and control circuit (30, 32, 34) for receiving and processing control data from vehicle applications (12, 14, 16) for setting dynamic ranges of the sensors (18, 20, 22, 24, 26, 28) of the sensor cluster (10) during operation of the sensor cluster (10) is formed.

Description

The The invention relates to an interface and control circuit for a sensor cluster for provision of sensor data for Vehicle applications according to claim 1.

to Improvement of comfort and safety in traffic increasingly driver assistance systems and occupant safety or Protective systems used in vehicles to ensure the most comfortable and safe Driving as well as possible effective protection against accidents to ensure. An improvement in the protective effect of inmates is here in particular achieved by the known occupant protection systems such Airbag and Gurtstrammereinrichtungen reinforced by so-called rollover systems and rollover protection features added to protect the occupants especially in accidents with rollover events. Increasingly, ESP (Electronic Stability Program) wizards are also becoming more modern Motor vehicles used to guide the vehicle during skidding its Actively support vehicles and accidents preferably to avoid. To improve driving comfort will continue Driver Support Assistance systems for it used to one as possible balanced ride to ensure. All of the aforementioned systems are based on the processing of signals a variety of sensors used in the vehicle. Individual sensors can also for various applications are used in the vehicle, for example a rotation rate sensor for both a rollover protection function as well as for an ESP system.

task It is the object of the present invention to provide an interface and control circuit for a Sensor cluster to propose the sensor data for various vehicle applications can provide.

These Task is by an interface and control circuit with the features of claim 1 solved. Further embodiments The invention will become apparent from the dependent claims.

One The essential idea of the invention is a sensor cluster to provide with a variety of sensors, one of these or several of the sensors have adjustable dynamic ranges to for different Vehicle applications, and also to provide a means of the sensor output characteristics, especially dynamic ranges the individual sensors or sensor channels of the sensor cluster also in the Operation of the sensor cluster, in particular set in real-time operation to be able to above all (continuously) to be able to configure freely. To obtain an application-related ideal sensor output characteristics can for configuration, current operating parameters are taken into account become.

The The present invention now relates, according to one embodiment an interface and control circuit for a sensor cluster to provide Sensor data for Vehicle applications, which has a plurality of sensors, adjustable dynamic ranges from these one or more of the sensors , wherein the interface and control circuit for receiving and processing control data from a vehicle application for adjustment one or more dynamic ranges of the sensors of the sensor cluster while the operation of the sensor cluster is formed. The interface and control circuit may, for example, as a stand-alone module or even be designed as an integrated circuit, the or the in a sensor cluster or a control unit for various vehicle applications can be integrated. In particular, under vehicle application the aforementioned Safety systems understood that are increasing in modern motor vehicles be used.

The Circuit can according to a another embodiment of the invention for receiving and processing digital sensor data from sensors of the sensor cluster and for digital bidirectional communication be formed with vehicle applications. The digital communication has the advantage of a lower susceptibility to interference in the vehicle, as transmitted Digital data better through suitable protocols against transmission errors and disturbances can be protected as analog signals.

Farther can according to a embodiment of the invention, the circuit for sequentially summarizing received digital sensor data in a transmission frame protocol and for communication with vehicle applications according to the transmission frame protocol be educated. The use of a transmission frame protocol has the advantage that the sensor data is transmitted serially can be which reduces the amount of wiring in the vehicle compared to a parallel one data transfer can be significantly reduced.

The circuit may further be configured in accordance with an embodiment of the invention to assign a specific information block of a transmission frame of the transmission frame protocol to each of the sensors of the sensor cluster. As a result, it is in principle not necessary to transmit special identifications of sensors per frame, since a receiver alone uses the information block or the position of the information block in the transmission frame in the protocol can identify the sensor. This can provide more capacity for the transmission of sensor data or the frames can be shorter.

Further can the circuit according to a embodiment be formed of the invention, sensor data in each information block and dynamic range data of the associated sensor. A receiver Frame can thereby determine which dynamic range the sensor providing the sensor data present in the information block works, or on which dynamic range he is set. This allows it to the recipient, to optimize the processing of the received sensor data, in particular the processing of the sensor data to the set dynamic range to adapt to the sensor.

According to one another embodiment the invention, the circuit may be formed on sensors of the Sensor Clusters Configuration parameters with data for setting the dynamic ranges of the sensors to send. These configuration parameters can transmitted for example in digital form to the sensors For example, as a kind of commands to set the dynamic ranges. The configuration parameters can also be transmitted as configuration parameter sets in which ordered different setting criteria for a sensor are specified, for example, a criterion for the setting the dynamic range of the sensor, another criterion for validity of the dynamic range to be set, whereby the sensor provides the desired Dynamic range only for a period of time corresponding to the transmitted validity can be set, and after the period of time back to the original Can switch the dynamic range automatically. Alternatively, can be provided that always the last transmitted configuration parameter set as long as validity has until a new configuration parameter set is transmitted.

The Circuitry may continue according to one embodiment be formed of the invention, to sensors of the sensor cluster cyclically different configuration parameters with data for Setting different dynamic ranges to send the sensor. For example, it may be necessary for a particular sensor, the for various vehicle applications is needed cyclically between switches different dynamic ranges, each to a specific one Vehicle application are adjusted. It is conceivable, for example, that a rotation rate sensor of a vehicle dynamics control and a rollover protection system is used and for Each of these two vehicle applications have different dynamic ranges (Sensor output characteristics) of the sensor are required.

In a further embodiment According to the invention, the circuit can also be designed as control data Receive identifiers for the identification of vehicle applications and the for the identified vehicle applications suitable dynamic ranges the for identify the identified vehicle applications need sensors of the sensor cluster. For example, you can in the circuit the for various vehicle applications required dynamic ranges be stored by sensors together with corresponding identification data to the vehicle application. Once the circuit as a tax date a Can receive identification of a particular vehicle application they all the dynamic ranges for the vehicle application required Load sensors from an internal memory and the sensors accordingly to adjust.

The invention further relates, in one embodiment, to a sensor cluster for providing sensor data for vehicle applications having a plurality of sensors, of which one or more of the sensors have adjustable dynamic ranges, and
an interface and control circuit according to the invention and as described above. Such a sensor cluster can be designed as a vehicle component that is offered for installation in motor vehicles.

Finally, concerns the invention in one embodiment the use of an interface and control circuit according to Invention and as described above in a vehicle, wherein the Circuit between a sensor cluster in the vehicle and different Vehicle applications is switched.

Further Advantages and applications The present invention will become apparent from the following description in conjunction with the embodiment (s) shown in the drawing (s).

In the description, in the claims, in the abstract and in the drawing (s) the in the one listed below List of reference symbols used terms and associated reference numerals used.

The Drawing (s) show / point in

1 a schematic diagram of a sensor cluster with various sensors and an interface and control circuit according to an embodiment of the invention, and

2 an embodiment of a protocol frame or transmission frame protocol according to the invention, as determined by the in 1 shown interface and control circuit can be implemented.

in the Following can identical and / or functionally identical elements with the same reference numerals be provided. The absolute values given below and dimensions are only exemplary values and do not represent a limitation of Invention on such dimensions.

As already mentioned above, an essential idea of the invention is that the sensor output characteristics one or more sensor channels of a sensor cluster even in real-time mode (continuous) free are configurable, wherein to obtain an application-related ideal sensor output characteristic for configuration current Operating parameters are taken into account can. About these sensor-output characteristics to be able to realize can the sensor signals or sensor data of the individual sensor channels also while active mode (cyclic measured value acquisition) by means of programming the current ones in reality existing conditions or application requirements are adjusted.

Under the facts of the "current in reality present conditions " the parameters, such as airspeed, relative differential speed to a preceding vehicle or to an oncoming vehicle Vehicle, obstacle object, obstacle mass, etc. to understand.

Under the facts of the "application request" is, for example for a rate of rotation sensor, the sensitivity parameter of the angle of rotation per second or the rotational angle to be displayed per second, where, for example, an application for chassis control or Vehicle dynamics control a dynamic of about 40 degrees / second, and a Application for rollover / rollover detection requires a dynamic of about 250 degrees / second.

1 now shows an embodiment of a sensor cluster 10 for use in a motor vehicle for vehicle applications 12 . 14 and 16 that process both accelerometer sensor data and gyro sensor data. The sensor cluster 10 allows, in principle, the use of a sensor for multiple vehicle applications with different demands on the dynamic range of the sensor, as will be explained in more detail below.

The sensor cluster 10 has individual acceleration sensors 18 . 20 . 22 ("Ax", "ay", "az") arranged to detect the acceleration of the vehicle in its longitudinal (x), transverse (y) and vertical axis (z). Furthermore, the sensor cluster points 10 Rate of rotation or yaw rate sensors 24 . 26 . 28 ("Ωx", "ωy", "ωz") arranged to detect a rotational movement of the vehicle about its longitudinal, transverse and vertical axis. The sensors 18 . 20 . 22 . 24 . 26 and 28 provide digital output signals, ie sensor data in digital form. For this purpose, they each have appropriate digital interface logic, which can also ensure the most error-free and error-free transmission of sensor data by using checksums such as Cyclic Redundancy Check (CRC) or the like in digital art usual error detection and correction techniques.

The sensor data, which are often referred to as sensor channels are, by means of logic (μC) 30 sequentially summarized, that is arranged in a protocol with transmission frames one behind the other. For this purpose, the sensor data of each sensor are assigned to specific information blocks in the context of the protocol, as in 2 is shown and will be explained in more detail below.

The logic 30 transmits the sensor data sequentially arranged in the transmission frame protocol to an interface 32 , which may be formed for example in the form of an SPI (Serial Parallel Interface) interface and the actual serial data transmission to the vehicle applications 12 . 14 and 16 takes over. the interface 32 may also be from the vehicle applications 12 . 14 and 16 Receive and process control signals with which the dynamic ranges of the individual sensors of the particular situation controlled by the control command sending vehicle application according to the situation in real time to be adjusted. The adaptation is done by dynamic range adjustment circuits 34 that by the interface 32 Controlled accordingly the dynamic ranges of the individual sensors as required by a vehicle application and / or set.

For example, with each data request by a vehicle application, a configuration parameter set can be transmitted to the sensor cluster, which is provided by the interface 32 is processed such that the sensor cluster in the following or next provided "data set" provides the individual sensor signal information corresponding to the requested configuration parameter set at the interface. Depending on the vehicle application, the configuration parameter set management in the sensor cluster can be implemented in such a way that, unless a new configuration parameter set is communicated, the configuration parameter set last transmitted automatically remains constant, and the sensor cluster automatically provides the "data sets" cyclically at the interface according to this configuration parameter set.

During active operation of the sensor cluster 10 For example, the information from yaw rate sensors ("ωx", "ωy", "ωz") may also be provided alternately in sensor output characteristic dynamics (40 degrees / second, 250 degrees / second). A resulting halving of the data transmission rate for the downstream vehicle applications is generally irrelevant since the rotation rate information (sensor data originating from the rotation rate sensors), as compared to acceleration information (sensor data from acceleration sensors), is generally required at a lower transmission rate.

In front Especially with acceleration information, the sensor cluster concept allows for real-time a sensor output characteristic dynamic adjustment can be made, wherein usually at a low vehicle speed, a low Dynamics and a great sensitivity (mV / g) is because in a low-speed accident with a rigid barrier (eg tree) lower acceleration amplitudes are expected, whereas at a high vehicle speed, a high dynamic range and low sensitivity (mV / g) is to be selected, because in a high-speed accident with a rigid Barrier (eg tree) to expect high acceleration amplitudes are.

Provided instead of a rigid obstacle by means of an environmental detection Systems (eg distance warning system) detects a moving obstacle is analogous to this, instead of the airspeed, the relative Speed to the leading obstacle or to the oncoming one Obstacle as influencing parameter considered accordingly become.

As well can accordingly, the mass ratios of the obstacle as influencing parameter taken into account because of an obstacle with large mass, large acceleration amplitudes whereas in the case of an obstacle with low mass, low acceleration amplitudes are to be expected.

Under The term dynamic range is, for example, in the simplest case the measuring range of an A / D converter input (0 Volt-5 Volt) or the exploitation of the depth of a digital protocol of the respective Application to understand. Under the term dynamic resolution range or dynamic presentation area are the characteristics or the specific data of a sensor to understand which are mapped to the respective output Need to become. As an explanatory An example is a rotation rate sensor with a representative measuring range mentioned by 250 degrees / second, in which the output at a corresponding 250 degrees turn (per Second) of the sensor according to its maximum to be displayed Output dynamic range for representation (illustration) of the sensor measurement signal controls or uses. This may vary depending on the sensor output signal by an analogous size or to a digital transmission protocol an interface, with a corresponding depth of the interface protocol, act.

2 shows the realization of a transmission frame protocol 36 or transmission frame 38 . 40 in which, for the sake of simplicity, only the "signal channel information blocks" 42 are shown, the individual sensors are assigned, as shown by the registered in the blocks sensor identifiers. The protocol may be preceded by start & sync bits or may be appended with check, parity, CRC, or other check bits required to secure the protocol, these bits being in 2 again not shown for reasons of simplicity. Top in 2 is the transmission frame 38 for the time t and below the transmission frame 40 for the subsequent time t + 1, wherein between the two frames switching the dynamic ranges of all sensors 18 . 20 . 22 . 24 . 26 . 28 of the sensor cluster 10 is done.

Every transmission frame 38 includes several information blocks. Some information blocks 42 is a specific sensor 18 . 20 . 22 . 24 . 26 . 28 of the sensor cluster 10 assigned, other information blocks are unused ("-"). In an information block associated with a sensor 42 Sensor data and information about the dynamic range of the sensor are transmitted, indicated for example by "ax - 100", ie sensor data of the sensor 18 with a set dynamic range 100 , The individual sensor signal information in the two transmission frames 38 and 40 can alternate in their dynamic ranges at the interface 32 to be provided.

10

Sensor Cluster

12

Vehicle Application

14

Vehicle Application

16

Vehicle Application

18

Acceleration sensor "ax" in x-direction

20

Acceleration sensor "ay" in y-direction

22

Acceleration sensor "az" in z-direction

24

Rotation rate sensor "ωx" around the X axis

26

Rotation rate sensor "ωy" around the y-axis

28

Rotation rate sensor "ωz" around the z-axis

30

logic (.Mu.C)

32

interface

34

Sensor dynamic range matching circuit

36

Transmission frame protocol

38

transmission frame at time t

40

transmission frame at time t + 1

42

Information block in the transmission frame 38 . 40

Claims (10)

Interface and control circuit ( 30 . 32 . 34 ) for a sensor cluster ( 10 ) for providing sensor data for vehicle applications ( 12 . 14 . 16 ), which has a large number of sensors ( 18 . 20 . 22 . 24 . 26 . 28 ), of which one or more of the sensors have adjustable dynamic ranges, the interface and control circuit ( 30 . 32 . 34 ) for receiving and processing control data from a vehicle application ( 12 . 14 . 16 ) for adjusting one or more dynamic ranges of the sensors ( 18 . 20 . 22 . 24 . 26 . 28 ) of the sensor cluster ( 10 ) during operation of the sensor cluster ( 10 ) is trained. Circuit according to Claim 1, characterized in that it is used to receive and process digital sensor data from sensors ( 18 . 20 . 22 . 24 . 26 . 28 ) of the sensor cluster ( 10 ) and for digital bidirectional communication with vehicle applications ( 12 . 14 . 16 ) is trained. Circuit according to Claim 2, characterized in that it is used for sequentially combining received digital sensor data in a transmission frame protocol ( 36 ) and for communication with vehicle applications ( 12 . 14 . 16 ) according to the transmission frame protocol ( 36 ) is trained. Circuit according to Claim 3, characterized in that it is designed to correspond to each of the sensors ( 18 . 20 . 22 . 24 . 26 . 28 ) of the sensor cluster ( 10 ) a certain information block ( 42 ) of a transmission frame ( 38 . 40 ) of the transmission frame protocol ( 36 ). Circuit according to claim 4, characterized in that it is designed in each information block ( 42 ) To transmit sensor data and dynamic range data of the associated sensor. Circuit according to one of the preceding claims, characterized in that it is designed to be connected to sensors ( 18 . 20 . 22 . 24 . 26 . 28 ) of the sensor cluster ( 10 ) To send configuration parameters with data for setting the dynamic ranges of the sensors. Circuit according to Claim 6, characterized in that it is designed to be connected to sensors ( 18 . 20 . 22 . 24 . 26 . 28 ) of the sensor cluster ( 10 ) cyclically sending different configuration parameters with data for setting different dynamic ranges of the sensors. Circuit according to one of the preceding claims, characterized in that it is designed as a control data identifiers for the identification of vehicle applications ( 12 . 14 . 16 ) and the dynamic ranges of the sensors required for the identified vehicle applications ( 18 . 20 . 22 . 24 . 26 . 28 ) of the sensor cluster ( 10 ). Sensor cluster ( 10 ) for providing sensor data for vehicle applications ( 12 . 14 . 16 ) with a plurality of sensors ( 18 . 20 . 22 . 24 . 26 . 28 ), of which one or more of the sensors have adjustable dynamic ranges, and an interface and control circuit ( 30 . 32 . 34 ) according to any one of the preceding claims. Use of an interface and control circuit ( 30 . 32 . 34 ) according to one of claims 1 to 8 in a vehicle, wherein the circuit between a sensor cluster ( 10 ) in the vehicle and various vehicle applications ( 12 . 14 . 16 ) is switched.