DE102004032048A1 - Object e.g. vehicle, orientation determining method, involves sending impulses from one object in two measuring channels, where length of one object is determined relative to another object based on measured impulse values of all channels - Google Patents

Abstract

The method involves transmitting impulses (Ia,Ib,Ic) from an object (1) in two of measuring channels, reflecting at another object (2), and receiving from the object (1). A length (L) of the object (1) is determined relative to the object (2) based on the measured values of the received impulses of all the channels. A sum of all amplitude values of the received impulse is determined with each channel as measured value. Independent claims are also included for the following: (A) an object e.g. vehicle, orientation determining device; and (B) an application of the object e.g. vehicle, orientation determining method.

Description

The The invention relates to a method and a device for determination the orientation of a first object, eg. As a vehicle, too a second object, e.g. B. another vehicle or person or any other item.

In Vehicles are becoming increasingly surveillance systems for measuring distances to obstacles in the driving area or vehicles in front used. Known measuring methods for determining the distance are generally based on measuring the transit time of a measuring medium, such as radar pulses, microwaves, ultrasonic waves and infrared radiation or a triangulation method.

From the EP 0 312 524 B1 For example, there is known a method and a device for measuring distance by processing optical pulse signals, comprising measuring the distance between a transceiver for optical pulse signals and a target by emitting optical pulse signals, receiving the signals reflected from the target, converting the received optical signals into digital electrical signals and subsequent signal processing is derived a measurement criterion for the distance information from a sum signal, which is formed by summing N consecutive reflected signals.

From the DE 101 39 237 A1 a further method and apparatus for distance measurement is known, which has a detector element for receiving a light beam reflected at an object, wherein means for deflecting the light beam are provided on the detector element. With this device, both the distance and the associated position of the object due to the angular position of the deflecting means, for example, from the detected, reflected at an existing object in the measuring range continuous light beam by the Laufzeitmethode. B. a polygon mirror, determine.

The Known devices are generally referred to as so-called PreCrash sensors used in vehicles. These sensors are used to detect a potential Accident situation in advance (= PreCrash situation), d. H. a situation, the most prevalent Probability will lead to an accident. The one or the other in a sensor arranged sensors usually detect the Distance between one's own vehicle and one in front Vehicle as well as the relative speed of the preceding vehicle Vehicle. This information becomes a central control unit supplied to the on-board information, such. For example, the speed of your own vehicle become. Decreases the speed of the preceding vehicle Vehicle very fast, so also reduces the distance between the own vehicle and the preceding vehicle accordingly and it can become a possible Accident situation come.

through the central control unit changes the distance and speed recorded and under or exceeded of preset limit values possibly existing in the vehicle active and / or passive safety systems triggered or activated. A disadvantage the sensors described is that these are generally the Distance to a preceding object, such. B. to a preceding Vehicle and its speed, capture, by means of which only one rough angle estimation the position of the two objects is derived from each other.

Of the Invention is based on the object, a simple method for Determining the orientation of a first object to a second Object and a particularly suitable device for carrying out the Specify method.

The in terms of of the method specified by the invention the characteristics of the independent Claim 1 solved. The regarding the Device task is according to the invention by the features of the independent claim 15 solved. Advantageous developments are the subject of the dependent claims.

In the method for determining the orientation of a first object to a second object pulses are emitted from the first object in at least two, in particular separately evaluable measuring channels, reflected on the second object and received by the first object. On the basis of measured values of the received pulses of all measuring channels, the relative position of the first object to the second object is then determined. By means of such a multi-channel measuring method, the alignment or orientation of a first object, for. As a vehicle, to another object, eg. As an obstacle or a vehicle in front, be determined. Due to the multi-channel measuring method and the resulting direction information in the form of the angle determination based on the measured values of at least two separately evaluable measuring channels, a largely accurate method for evaluating the object orientation and a simple plausibility check of these is made possible. As impulse is at For example, a time-limited wave, z. As a radar pulse in the microwave, ultrasonic wave or infrared wave range used. In addition, the respective pulse of a measuring channel may differ from the pulse of the other measuring channels or, for example, by a different frequency or different polarization or modulation.

moreover are determined by assignment of detection ranges for a sensor associated with the respective measuring channel the measuring channels separated from each other. In this case, each measuring channel has a preferred direction with an associated Detection area.

To the Edge of the detection ranges of adjacent measurement channels comes it's an overlap, so that an object identified in several detection areas is assigned to the relevant measuring channel.

In an embodiment of the multichannel measuring method are measured values per measuring channel Amplitude values of over determined a predetermined period of received pulse. Based the size of the amplitude values adjacent measuring channels can the direction of the second object or another in the detection or measuring range of the first object lying further object determined become. Alternatively or in addition For each measuring channel, the measured value is the sum of all the amplitude values of the received pulse determined. In other words, that in the respective Measuring channel received pulse signal, in particular its sampling or Amplitude values are added to a sum signal.

When a further or alternative embodiment is per measuring channel as Measured value based on the amplitude values of the received pulse Maximum value determined. Furthermore, alternatively or additionally each Measuring channel as a measured value based on the amplitude values of the received Pulse averages determined. In this way, all of the second object reflects measured values into a single value summarized.

For the determination the orientation of several objects to each other starting from the first Object, in particular for determining the relative position of the first Object to the second object, the measured values of those pulses several measuring channels determined and considered, the approximately synchronous, d. H. at about the same time or at intervals of a few milliseconds, z. In slowly moving objects, have been sent from the first object. Through the synchronous transmission the impulses of selected ones or all measurement channels ensures that the received impulses and the resulting resulting direction information sufficiently accurate and secure is.

to Determination of the smallest object distance of all measuring channels based on the measured values of several measuring channels a minimum value, d. H. the smallest Measured value of all measuring channels or selected Measuring channels, z. B. by comparison. The smallest measured value Measuring channel indicates the smallest object distance. In this way a distance vector of the first object to the second object is determined. For deselecting individual measuring channels on which the minimum value determination is based, eg. From measurement channels, whose measured values do not detect an object or a distant object, become those measuring channels For example, disabled or no longer considered, their readings by a predetermined value, in particular distance value, greater than are the minimum value. In other words, those measuring channels are deselected whose measured object distance a maximum distance to the smallest object distance exceeds another measuring channel. On the basis of the measured values of the remaining measuring channels, for example by means of Focusing the amplitude values of these measurement channels the orientation or relative position of the second object, e.g. An obstacle, destined for the first object. Alternatively or additionally, based on the measured values the received pulses considered those measuring channels whose measured values the largest amplitude value and / or the next smaller one Have amplitude value.

Also the case that in the detection or measurement area around the first object several more objects are detected is by means of the multi-channel Measuring method determinable. For this example, the measured values several measuring channels to see whether in middle measuring channel the smallest measured value, z. B. the smallest amplitude value, occurs. In this case, no determination of the relative position executed.

In addition, at the possible ones described above multichannel measuring method the measured values of the respective measuring channel by a correction factor, e.g. B. for the correction of stray light in Detection range, to be corrected. The correction factor is taken into account while the characteristic sensitivity of the respective measuring channel and the associated Sensor. As an extension is also a filtering of the particular Orientation or relative position with an adaptive observer to estimate the Direction information possible. As a result, for example by trajectory of the measured values of the received pulses more Parameters, such. B. distance, speed, angle and / or Angular velocity of the second object to the first object, determined become.

The Determination of such parameters is used, for example, the detection from the first object, z. B. a vehicle, passing second Objects, especially for early Detection of a possible Risk of collision and to avoid this. For this purpose, the Further on the change the measured values and the resulting change in the angular velocity a lateral disappearance of the second object or other objects monitored from the detection and measuring range of the first object become. A disadvantage of such an adaptive system (also Called observer approach) is the nonlinear course of the angle and the angular velocity, z. B. depending on the distance. To get around this, a two-dimensional state representation is made the object trajectory in dependence executed by the distance and angle sizes. But this leads to a higher computing power. Depending on the function and degree of accuracy of the direction information is activates or deactivates the two-dimensional state representation.

Of Further can over corresponding correction factors a spin movement and a rapid change of direction of the own vehicle (= first object) in the determination of the relative Location of the second object to the first object taken into account. For this purpose is another adaptive system, e.g. As an observer with vehicle-related input variables, eg. B. over the driving dynamics, used. For a different measurement and Monitoring areas covering monitoring areas of the first object, e.g. From 90 °, 180 ° or 360 °, become several Measuring channels, each comprising a sensor used. To determine the relative position based on measured values of several measuring channels a given sensor of a selected measuring channel, the measured values the other measurement channels fed. Alternatively or additionally the measured values of all measuring channels fed to a central unit. Depending on the type and structure of the device, the calculation of the relative Location executed in the given sensor and / or in the central unit.

The Device for determining the orientation of a first object to a second object comprises at least two measurement channels on the first object, each measuring channel having a sensor for emitting an associated pulse and for receiving the pulse reflected at the second object, based on measured values of the received pulses of all measuring channels, the relative position of the first object to the second object is determined. As a sensor For example, a pulse generator with integrated pulse detector, a laser scanner or other optical transmit / receive sensor used. The laser scanner works, for example, at a scanning frequency of 10 Hz and a pulse frequency of about 15 kHz. Depending on the application of the respective optical sensor can this a range of 0 m to 250 m, in particular from 0 m to 40 m or from 0 m to 25 m have. The sensors are for a partial or complete all-round monitoring of the first object, e.g. B. a vehicle distributed. Preferably, the sensors are arranged close to each other and form a Unit. The respective sensor has a measuring point with several Detection areas with a detection angle of at least 2 ° to 50 °, preferably from 5 °, 15 ° or 40 °, up. It is for one Remote area with a cover of up to 30 m preferably one Detection range of 5 ° provided. For one preferably good coverage in the near range up to 10 m, the sensor in question a detection range with a detection angle of 15 °.

The particular advantages of the invention are that by means of a multi-channel measurement method based on a simple amplitude evaluation the measured values of all measuring channels a simple and secure determination of the orientation of a first Object to a second object is enabled. In particular a simple continuous and possibly complete monitoring of the surrounding area of the first object possible. moreover the device and method are suitable for pre-crash detection, for use in an active safety system of a vehicle, in particular for influencing the driving dynamics of the vehicle. Also, the procedure can for the optimized reversible and / or non-reversible release of Restraining means or for correcting sitting positions or closing Windows are used.

embodiments The invention will be explained in more detail with reference to a drawing. Show:

1 . 2 a schematic representation of a device for determining the orientation of a first object to a second object, and

3 a schematic representation with detected in the detection range of the first object several other objects.

each other corresponding parts are in all figures with the same reference numerals Mistake.

1 shows a first object 1 , z. B. a vehicle which is stationary or moves in the direction R, and a detectable in the measuring or detection range EB second object 2 , z. B. an obstacle, a person or another vehicle. To the Bestim tion of the relative position L of the second object 2 to the first object 1 includes the first object 1 a device 4 which have multiple measurement channels 6a to 6c which each have a sensor 8a to 8c is assigned has. Depending on the type and structure and function of the device 4 , z. As a turn sensor, lane change sensor, sensor for pedestrian protection or sensor for automatic emergency braking, the device 4 at the first object 1 arranged on the front, back and / or on the long sides. The device is preferred 4 as a unit with multiple sensors 8a to 8c executed. Here are the sensors 8a to 8c arranged as close to each other as possible. Alternatively, multiple devices 4 with several sensors 8a to 8c at the first object 1 be arranged distributed. Also, the second object 2 , z. B. another vehicle, with a device 4 with several sensors 8a to 8c be equipped.

Depending on the training and type and structure of the device 4 indicates the respective sensor 8a to 8c an associated measuring channel 10a to 10c with an associated detection angle α _a to α _c of at least 2 ° to 50 °, preferably of 5 °, 15 ° and / or 40 °, on. The detection angles α _a to α _c may vary depending on the embodiment and have larger or smaller angles or any combination of different angles. In the exemplary embodiment, the two outer sensors 8a and 8c each have a detection angle α _a or α _c of about 60 ° and the middle sensor α _b an angle of about 20 °. The respective sensor can be used to monitor a long-range distance of up to 30 m 8a to 8c preferably an associated detection angle α _a to α _c of 5 ° and for monitoring a near range of up to 10 m an associated detection angle α _a to α _c of 15 °.

For determining the relative position L of the second object 2 to the first object 1 is done by means of the sensors 8a to 8c in the measuring channels 10a to 10c in each case one pulse Ia to Ic emits, that of the object 2 reflected and from the respective sensor 8a to 8c received and converted into electrical measurements. The respective sensor 8a to 8c For this purpose, for example, as a transceiver unit, in particular as an optical transceiver unit, z. B. as a laser scanner, a pulse generator with integrated pulse detector.

The method for determining the orientation of the first object 1 to the second object 2 is described below on the basis of 2 described in more detail. In this case, the relative position L in a simple form on the basis of measured values of the received pulses Ia to Ic of all measuring channels 10a to 10c certainly. For a sufficiently accurate determination of the relative position L of the first object 1 to the second object 2 In particular, the measured values of those pulses Ia to Ic are determined which are related to the measuring channels 10a to 10c related synchronously from the first object 1 have been sent out.

When Measured values become, for example, amplitude values of over one predetermined period received pulse Ia to Ic determined. The amplitude value of a pulse Ia to Ic in this case is the sample value Understood.

Alternatively or additionally, the sum of all the amplitude values of a received pulse Ia, Ib or Ic or a mean value formed from the amplitude values of a received pulse Ia, Ib or Ic can be determined as the measured value. In other words, it will ever be measuring channel 10a to 10c a sum value or an average of all the amplitude values is formed. The summation value is understood by adding all the sampled values of the periodically transmitted pulse sequence acquired within a sampling interval and leads to an elevation of the measured values of the received pulse Ia, Ib or Ic and thus to an increase in the sensitivity and the measuring accuracy of the device 4 , Also, a maximum value can be determined as a measured value on the basis of the amplitude values of a received pulse Ia, Ib or Ic, for example by comparison of all amplitude values determined within one sampling interval.

Depending on the type and structure of the device 4 is one of the sensors 8a to 8c and / or a central processing unit 12 , z. B. in a trained as a vehicle first object 1 a control unit for determining information, such as detection of the object present in the detection area EB 2 , Determining the direction of movement of the second object 2 , Determining the relative position L of the second object 2 to the first object 1 , Classification of the second object 2 or prediction of a possible collision situation on the basis of the measured values of the received pulses Ia to Ic of all measuring channels 10a to 10c intended. For this, the measured values become the relevant sensor 8a to 8c or the central unit 12 fed.

As information is per measuring channel 10a to 10c the distance or distance a of the first object 1 from the second object 2 determined on the basis of the change in the measured value, in particular the amplitude values of the respectively received pulse Ia to Ic, and / or on the basis of the transit time of the respective pulse Ia to Ic. For a measuring channel 10a to 10c comprehensive evaluation of the measured values is in a possible embodiment of the method, for example by comparing the measured values of several measurement channels 10a to 10c , a minimum value determined. Based on the minimum value, the smallest detectable distance a of the first object 1 to the second object 2 identified.

For a simple and fast evaluation as well as analysis of the received pulses Ia to Ic, those measuring channels are used 10a to 10c deactivated, whose measured values are greater than the minimum value by a predetermined value, in particular distance value. Thus, only those measuring channels are left 10a to 10c takes into account that a second object 2 detect at a critical distance a. In 2 is the measuring channel 10a Deactivated. An evaluation of the measured values takes place only for the measuring channels 10b and 10c ,

Alternatively or additionally, in the analysis of the received pulses Ia to Ic only those measuring channels 10a to 10c be considered, the measured values have the largest and the next smaller amplitude value. As a result, possible measurement errors or a pulse reflected by a further object can be excluded from the analysis. Furthermore, the measured values of the respective measuring channel can be used 10a to 10c to be corrected by a correction factor, e.g. B. to reduce the signal component of any stray light or poor environmental conditions, such as rain or snow, which affect the detection range EB, caused interference or even delete.

In order to determine the relative position L, the distances a of the respective pulses Ib and Ic determined on the basis of the measured values are determined. Depending on the type of device 4 assign the neighboring sensors 8b and 8c the activated measuring channels 10b respectively. 10c each other an angular resolution, z. From 5 ° to monitoring a long range and / or 15 ° to monitoring a short range. It is based on the known beam angle β _b and β _{c of} the sensors 8b respectively. 8c and the distances a determined the relative position L of the first object 1 to the second object 2 certainly.

In addition, depending on the nature and extent of the evaluation of the measured values, a direction vector for the second object can also be provided in a simple manner 2 be determined on the basis of a direction angle δ, on the basis of which, for example, the direction of travel of the second object 2 can be determined. Thus, based on the determination of the distances a and the radiation angle β _b and β _c, the relative position L and on the basis of the direction vector, the movement of the second object 2 to a large extent fully described.

3 shows a further illustration for carrying out the multi-channel measuring method, wherein in the detection range EB of the device 4 several objects 2 be detected. The determination of the respective relative position L of the first object 1 to the relevant second object 2 takes place as described above. The described multi-channel measuring method and the associated device 4 are preferably used as a monitoring system in a vehicle for the early detection of a possible risk of collision. In this use case, the first object is 1 a vehicle, the second objects 2 may be an obstacle, a person and / or another vehicle. Shall movements around the first object 1 are detected, so are several devices 4 around the first object 1 arranged. In the combination of all devices 4 with the multitude of sensors 8a to 8c and the associated measurement channels 10a to 10c then, for example, a movement of the first object 1 passing second object to be determined and monitored.

1

first object

2

second object

4

contraption

6a-6c

measuring channels

8a-8c

sensor

10a-10c

separately evaluable measuring channels

12

central processing unit

a

critical distance

EB

measurement or coverage area

Ia-Ib

Impulse

L

relative location

R

direction

α _a to α _c

angle of coverage

β _b, β _c

Beam

δ

directional angle

χ

tilt angle

Claims (19)

Method for determining the orientation of a first object ( 1 ) to a second object ( 2 ), where the first object ( 1 ) in at least two measuring channels ( 6a . 6b . 6c ) Pulses (Ia, Ib, Ic) emitted, at the second object ( 2 ) and from the first object ( 1 ), wherein based on measured values of the received pulses (Ia, Ib, Ic) of all measuring channels ( 6a . 6b . 6c ) the relative position (L) of the first object ( 1 ) to the second object ( 2 ) is determined. Method according to Claim 1, in which each measuring channel ( 6a . 6b . 6c ) are determined as measured values amplitude values of the pulse (Ia, Ib, Ic) received over a predetermined period of time. Method according to Claim 1 or 2, in which each measuring channel ( 6a . 6b . 6c ) the measured value is the sum of all the amplitude values of the received pulse (Ia, Ib, Ic). Method according to one of the preceding claims, in which each measuring channel ( 6a . 6b . 6c ) when Measured value based on the amplitude values of the received pulse (Ia, Ib, Ic) a maximum value is determined. Method according to one of the preceding claims, in which each measuring channel ( 6a . 6b . 6c ) is determined as a measured value on the basis of the amplitude values of the received pulse (Ia, Ib, Ic) an average value. Method according to one of the preceding claims, in which each measuring channel ( 6a . 6b . 6c ) the distance of the first object ( 1 ) from the second object ( 2 ) is determined on the basis of the change in the measured value, in particular the amplitude values of the received pulse (Ia, Ib, Ic), and / or on the basis of the transit time of the pulse (Ia, Ib, Ic). Method according to one of the preceding claims, in which the relative position (L) of the first object ( 1 ) to the second object ( 2 ) based on the measured values of those pulses (Ia, Ib, Ic), the measuring channel ( 6a . 6b . 6c ) synchronously from the first object ( 1 ) are determined. Method according to one of the preceding claims, in which, based on the measured values of a plurality of measuring channels ( 6a . 6b . 6c ) a minimum value is determined. Method according to Claim 8, in which, based on the measured values of a plurality of measuring channels ( 6a . 6b . 6c ) those measuring channels ( 6a . 6b . 6c ) whose measured values are greater than the minimum value by a predetermined distance value. Method according to one of the preceding claims, wherein on the basis of the measured values those measuring channels ( 6a . 6b . 6c ), whose measured values have the largest amplitude value and the next smaller amplitude value. Method according to one of the preceding claims, in which the measured values of the respective measuring channel ( 6a . 6b . 6c ) are corrected by a correction factor. Method according to one of the preceding claims, in which each measuring channel ( 6a . 6b . 6c ) a sensor ( 8a . 8b . 8c ) and measured values of the other measuring channels ( 6a . 6b . 6c ) a given sensor ( 8a . 8b . 8c ). Method according to Claim 12, in which the calculation of the relative position (L) in the given sensor ( 8a . 8b . 8c ) and / or in a central unit ( 12 ) is performed. 14: device ( 4 ) for determining the orientation of a first object ( 1 ) to a second object ( 2 ), in which at least two measuring channels ( 6a . 6b . 6c ) on the first object ( 1 ), each measuring channel ( 6a . 6b . 6c ) a sensor ( 8a . 8b . 8c ) for emitting an associated pulse (Ia, Ib, Ic) and for receiving the second object ( 2 ) reflected pulse (Ia, Ib, Ic), wherein based on measured values of the received pulses (Ia, Ib, Ic) of all measuring channels ( 6a . 6b . 6c ) the relative position (L) of the first object ( 1 ) to the second object ( 2 ) is determined. Contraption ( 4 ) according to claim 14, wherein the sensors ( 8a . 8b . 8c ) as close as possible to each other at the first object ( 1 ) are arranged and form a structural unit. Contraption ( 4 ) according to claim 14 or 15, wherein the respective sensor ( 8a . 8b . 8c ) has a measuring point with different detection ranges (EB) with a detection angle (α _a to α _c ) of at least 2 ° to 50 °, preferably of 5 ° or 15 °. Contraption ( 4 ) according to one of claims 14 to 16, wherein the relative position (L) in one of the sensors ( 8a . 8b . 8c ) and / or in a central unit ( 12 ) is determined. Use of the method according to one of claims 1 to 13 for pre-crash detection. Use of the method according to one of claims 1 to 13 for an active safety system, especially in a vehicle for Influencing the driving dynamics of the vehicle. Use of the method according to one of claims 1 to 13 for optimized reversible and / or non-reversible triggering of a or more retention means.