Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/87—Combinations of sonar systems
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
  • G01S15/06—Systems determining the position data of a target
  • G01S15/08—Systems for measuring distance only
  • G01S15/10—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves
  • G01S15/102—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves using transmission of pulses having some particular characteristics
  • G01S15/104—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves using transmission of pulses having some particular characteristics wherein the transmitted pulses use a frequency- or phase-modulated carrier wave
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
  • G01S15/06—Systems determining the position data of a target
  • G01S15/08—Systems for measuring distance only
  • G01S15/10—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves
  • G01S15/102—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves using transmission of pulses having some particular characteristics
  • G01S15/107—Systems for measuring distance only using transmission of interrupted, pulse-modulated waves using transmission of pulses having some particular characteristics using frequency agility of carrier wave
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
  • G01S15/06—Systems determining the position data of a target
  • G01S15/08—Systems for measuring distance only
  • G01S15/32—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
  • G01S15/325—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of coded signals, e.g. of phase-shift keyed [PSK] signals
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/88—Sonar systems specially adapted for specific applications
  • G01S15/93—Sonar systems specially adapted for specific applications for anti-collision purposes
  • G01S15/931—Sonar systems specially adapted for specific applications for anti-collision purposes of land vehicles
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/523—Details of pulse systems
  • G01S7/526—Receivers
  • G01S7/527—Extracting wanted echo signals
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52001—Auxiliary means for detecting or identifying sonar signals or the like, e.g. sonar jamming signals

Definitions

• the invention relates to a method for operating an ultrasonic sensor, as well as a distance measuring device with at least one ultrasonic sensor, which is operated according to the inventive method.
• Ultrasonic-based measuring systems are used to measure a distance to an object located in front of an ultrasonic sensor.
• the sensors used are based on the pulse / echo method.
• the ultrasonic sensor emits an ultrasonic pulse and measures the reflection of the ultrasonic pulse (echo) caused by an object.
• the distance between the ultrasonic sensor and the object is calculated using the measured echo time and the speed of sound.
• the ultrasonic sensor acts as transmitter to receiver.
• Known applications are, for example
• the transducer element of an ultrasonic sensor is excited to mechanical vibrations.
• the excitation results in resonant, ie operated at its resonant frequency converters exponential decay phase of the amplitude of the mechanical oscillation.
• the ultrasonic sensor may be in the ultrasonic sensor either due to production or by installation in a holder for holding, for example, on a
• the near zone is defined in particular as the region in the vicinity of the sensor in which a reflecting object leads to such a short transit time of the echo pulse that mechanical oscillation occurs after the echo pulse
• the invention is therefore based on the object of specifying a method for operating an ultrasonic sensor, in which the influence of parasitic vibrations is reduced, so that an improved Nahmessstage the ultrasonic sensor is achieved and the occurrence of incorrect measurements (also referred to as "false positives"), in particular is reduced in the vicinity.
• the invention is based on the observation that the expression of the parasitic oscillation depends on the type of excitation, in particular on the manifestation of the transmission pulse end, and that the parasitic oscillations have frequencies in certain frequency ranges.
• the invention therefore provides for operating an ultrasonic sensor in such a way that the excitation patterns (also referred to as "codes") are varied from shot to shot such that the frequency range at the end of the excitation, preferably the last 400 ⁇ s of the excitation pulse, is changed.
• At least two measuring cycles are carried out, preferably at least four.
• the determined object information from at least two measurement cycles are compared with each other and depending on the result of the comparison, a fault is detected. Under a disturbance becomes thereby
• Oscillation is caused, which in turn can result from manufacturing tolerances and / or the installation of the sensor in a holder.
• Ultrasonic sensor for measuring a distance with a special code to operate.
• Each code corresponds to a particular excitation pattern, it being provided that after each excitation for a new excitation another excitation pattern or a different code is used.
• the excitation pulses preferably differ within the last 400 ⁇ of the respective excitation pulse, the frequency characteristic of the
• Excitation pulses of two measuring cycles, in particular two immediately consecutive measuring cycles, at least during the last 400 ⁇ the duration of the respective excitation pulse differ.
• the excitation pulses preferably have a total duration of ⁇ to 3000 ⁇ 5, preferably ⁇ .
• a complete measurement cycle may be a
• the duration of a first excitation pulse of a first measurement cycle differs from the duration of a second excitation pulse of a second measurement cycle, wherein the second measurement cycle follows the time of the first measurement cycle.
• the second measuring cycle can directly follow the first measuring cycle. This means that no further signal is transmitted between the first and the second measuring cycle, but there may be a pause between the first and the second measuring cycle in which no excitation takes place.
• the second measurement cycle can not follow directly to the first measurement cycle, but instead a further excitation occurs between the first and the second measurement cycle.
• the amplitude of a first excitation pulse of a first measurement cycle may differ from the amplitude of a second excitation pulse of a second measurement cycle. This causes the
• the second measuring cycle can directly follow the first measuring cycle. This means that no further signal is transmitted between the first and the second measuring cycle, but there may be a pause between the first and the second measuring cycle in which no excitation takes place.
• the second measurement cycle can not immediately follow the first measurement cycle, but between the first and the second measurement cycle another
• the excitation pulses are preferably designed as frequency-modulated pulses.
• a frequency-modulated excitation pulse is to be understood as meaning any excitation pulse whose frequency changes during the pulse duration. In this case, continuous or discontinuous changes in the frequency can be provided. Alternatively or additionally, it is also possible to use pulses with a continuously constant excitation frequency.
• Excitation pulses by a, in particular linear, frequency response, modulated, in particular in a frequency range between 40 kHz and 60 kHz. This means that the frequency of the respective excitation pulse rises steadily and in particular linearly from a starting frequency or drops until an end frequency is reached. Such an excitation is also referred to as "chirp.”
• the start and end frequencies are preferably selected from the frequency range from 40 kHz to 60 kHz.
• the signal-to-noise ratio can be improved in an advantageous manner by using the known waveform of the excitation pulse in the selection of the filter in a known manner.
• object information with higher accuracy is determined.
• Measuring cycles calculates a probability that a detected object is actually present or that there is a faulty measurement. In this way, a suppression of sensor manufacturing and / or holder-related disturbances in the sense of false positives, in particular in the near range, can be achieved in a particularly efficient manner.
• a preferred embodiment of the invention are in the operation of the
• Ultrasonic sensor provided at least four measuring cycles, wherein one of the measuring cycles has an excitation pulse at a constant frequency.
• a distance measuring device in particular for a motor vehicle, which comprises at least one ultrasonic sensor which is operated according to one of the methods described above.
• a distance measuring device is provided, which comprises a plurality of ultrasonic sensors, which are operated in accordance with a method as described above, wherein the ultrasonic sensors on a
• Body part of a motor vehicle are arranged in a row.
• the ultrasonic sensors are operated in such a way that ultrasonic sensors arranged adjacent to one another have measurement cycles which do not overlap in time.
• Figure 1 shows schematically a distance measuring device with a plurality of ultrasonic sensors according to an embodiment of the invention.
• FIG. 2 shows four diagrams of possible frequency profiles for excitation pulses.
• FIG. 3 shows a table with a sequence of measuring cycles for different ones
• Ultrasonic sensors of a distance measuring device with a plurality of ultrasonic sensors according to an embodiment of the invention.
• Figure 1 shows schematically in plan view the rear of a motor vehicle 8 with a bumper 7, are arranged on the ultrasonic sensors 1, 2, 3, 4, 5, 6 in a row.
• the ultrasonic sensors 1, 2, 3, 4, 5, 6 are part of a
• Distance measuring device for detecting the environment of the motor vehicle 8. Furthermore, an object to be detected by means of the ultrasonic sensors 9 in the environment of the motor vehicle 8 is shown. It may be, for example, a traffic obstruction, such as a bucket, a street sign or a lantern as well as another vehicle.
• Each of the ultrasonic sensors 1, 2, 3, 4, 5 and 6 has an electroacoustic transducer, which by a frequency-modulated excitation pulse to
• the invention is not limited to the fact that the ultrasonic sensors are arranged at the rear of a motor vehicle 8.
• ultrasonic sensors may be arranged, for example, in the region of the front of the vehicle and / or on the sides of the motor vehicle 8.
• a transmission cone of a transmitted measuring signal 10 and a directional arrow 11, which indicates the transmission direction, are shown by way of example. It can be seen that the transmission cone hits the object 9, so that the measurement signal 10 is partially reflected by the object 9 in the direction of the ultrasonic sensor 3 in a second transmission cone (echo) 12.
• the ultrasonic sensor 3 registers the reflection, and the total elapsed time between emission of the transmission pulse and reception of the reflection is determined. From the elapsed time can be at a known signal speed, for example, the speed of sound in air of about 343 m / s, calculate the distance of the object 9 of the ultrasonic sensor 3.
• electroacoustic transducer of the ultrasonic sensor is excited.
• the ultrasound sensor 3 is operated in such a way that several measuring cycles are carried out successively. In each measurement cycle, another excitation pulse is used to excite the
• electroacoustic transducer used as in the previous measurement cycle.
• the excitation pulses differ during each of the last 400 is.
• frequency modulated excitation pulses as
• the excitation frequency is linearly changed from a start frequency to a target frequency during the excitation pulse, but the invention is not limited to this type of frequency modulation, it is also other excitation patterns Furthermore, for example, constant frequency profiles can be used, at least in sections, for the person skilled in the art, for which a variety of further design possibilities are known. According to a preferred embodiment of the invention is now provided for each of the ultrasonic sensors 1, 2, 3, 4, 5 and 6, the excitation pattern
• the frequency range of the frequency modulation at the end of the excitation preferably the last 400us of the excitation pulse, is changed.
• Exemplary excitation patterns for the frequency-modulated excitation pulses are shown in FIGS. 2 a) -d) in diagrams 20-23. In each case the frequency (in kHz) is plotted against the time (in is).
• This form of excitation pulse is denoted below by the symbol C3.
• the excitation pulse is a linear chirp of 43.5 kHz after 52.5 kHz with a duration of 1.6 ms. This means that the frequency range of the last 400 ⁇ corresponds to a linear frequency characteristic of 50.25 kHz to 52.5 kHz (see diagram 23 in FIG. 2d)). This form of an excitation pulse is described below with the symbol
• the excitation pulse is a 60 kHz to 52 kHz linear chirp with a duration of 0.4 ms. This means that the frequency range of the last 400 ⁇ corresponds to a linear frequency characteristic of
• Excitation pulse of 48 kHz with a duration of 170 is provided (see diagram 20 in Figure 2 a)). This form of an excitation pulse is denoted below by the symbol Cl.
• Ultrasonic sensors 1, 2, 3, 4, 5 and 6 are shown in tabular form in FIG.
• the rows of the table refer to time intervals that are available for a measuring cycle. In such a time interval, both the excitation of the electroacoustic transducer and the reception of reflected ultrasonic signals and the determination of an object information occur. These time intervals can each have the same length, but it can also be provided different lengths.
• the columns of the table each relate to an ultrasonic sensor 1, 2, 3, 4, 5 and 6.
• the ultrasonic sensor 1 at the beginning of the operation of the distance measuring device in a first time interval, according to its first measurement cycle driven with an excitation pulse of the form C3, the electroacoustic transducer of the ultrasonic sensor 1 is thus charged with a corresponding excitation pulse sends us a corresponding measurement signal ,
• the ultrasonic sensor 5 is driven with an excitation pulse of the form C4.
• the ultrasonic sensors 1 and 5 are not arranged adjacent to each other.
• the ultrasound sensors 2 and 6, each with an excitation pulse of the form Cl, are subsequently activated in a second time interval. Also applies to the ultrasonic sensors 2 and 6, that due to the relatively large spatial distance of the ultrasonic sensors 2 and 6 simultaneous operation is possible because the probability of mutual interference is reduced.
• Ultrasonic sensors 1 and 5 are each driven by an excitation pulse of the form Cl.
• the ultrasonic sensor 2 is driven with an excitation pulse of the form C4 and the ultrasonic sensor 6 is driven with an excitation pulse of the form C3.
• the ultrasonic sensor 1 is driven with an excitation pulse of the form C4 and the ultrasonic sensor 5 is driven with an excitation pulse of the form C3.
• Ultrasonic sensors 2 and 6 are each driven by an excitation pulse of the form C2.
• Ultrasonic sensors 1 and 5 are each driven by an excitation pulse of the form C2.
• Ultrasonic sensor 2 is driven with an excitation pulse of the form C3 and the ultrasonic sensor 6 is driven with an excitation pulse of the form C4.
• the measuring operation can be terminated or the scheme shown in Figure 3 can be repeated, or the distance measuring device can be operated with a different scheme.
• Ultrasound sensor considered by itself from shot to shot (ie in successive measuring cycles of the respective sensor)
• Stimulation pattern changes. For example, a measurement is carried out with the ultrasonic sensor 1 in the first time interval.
• the first time interval thus corresponds to the first measuring cycle of the ultrasonic sensor 1.
• the electro-acoustic transducer of the ultrasonic sensor 1 is excited with a frequency-modulated excitation pulse of the form C3 to mechanical vibrations. After completion of the measurement cycle, the ultrasonic sensor 1 remains passive until the second measurement cycle of the ultrasonic sensor 1 is performed in the fifth time interval. In this second measuring cycle, the electroacoustic transducer of the ultrasonic sensor 1 with a
• the third measuring cycle of the ultrasonic sensor 1 takes place in the ninth time interval.
• the fourth measuring cycle of the ultrasonic sensor 1 takes place in the thirteenth time interval. In each measurement cycle, the frequency response of the frequency-modulated excitation pulse thus differs. This also applies to all other ultrasonic sensors 2 to 6.

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• Engineering & Computer Science (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Physics & Mathematics (AREA)
• Computer Networks & Wireless Communication (AREA)
• General Physics & Mathematics (AREA)
• Acoustics & Sound (AREA)
• Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)

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• 2016
  • 2016-12-14 DE DE102016224928.2A patent/DE102016224928A1/de active Pending
• 2017
  • 2017-10-30 JP JP2019528622A patent/JP6816279B2/ja active Active
  • 2017-10-30 EP EP17791685.5A patent/EP3555661A1/de not_active Withdrawn
  • 2017-10-30 KR KR1020197019982A patent/KR102353624B1/ko active IP Right Grant
  • 2017-10-30 WO PCT/EP2017/077787 patent/WO2018108379A1/de unknown
  • 2017-10-30 US US16/468,369 patent/US11366207B2/en active Active
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