Method of and apparatus for providing information as to the existence or position of objects

• US 4,310,903 A
• Filed: 08/21/1979
• Issued: 01/12/1982
• Est. Priority Date: 08/21/1978
• Status: Expired

• Current Assignee: Leslie Kay
• Original Assignee: Leslie Kay
• Inventors: Kay, Leslie
• Primary Examiner(s): Farley, Richard A.
• Application Number:
  US06/068,432
• Time in Patent Office: 875 Days
• Field of Search: 367/102, 367/104, 367/910, 367/113, 367/116, 343/5 BL
• US Class Current: 367/102
• CPC Class Codes: G01S 15/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• CPC Class Codes: G09B 21/007 using both tactile and audible presentation of the information
• CPC Class Codes: Y10S 367/91 Portable sonar devices

Abstract

A method of and apparatus for locating an object by stress wave energy reflection in which the wave energy is transmitted as a beam by transmitting transducer elements, and is scanned through successive sectors of a field of view by imposing differential transmission delays on transmitting signals fed to the elements by means of a delay line. Indicator signals are developed in receiving channels connected respectively to receiving transducers providing binaural characteristics, and transducer providing monaural characteristics but collectively covering the field. An indicator means comprises any, or any combination, of audible means, visual means or tactile means the two latter providing coordinate displays. A receiving means includes spectral analysing means for segregating the indicator signals into separate different frequency bands, and delay means for imposing differential delays compensating for transit time of wave energy reflection in the medium correlated with different range bands before coordinate display.

Claims

1. In a method of providing information as to the existence or position of objects otherwise than by direct vision comprising the steps of, radiating stress wave energy (herein called the transmitted signal) from a station to a field of view, receiving at the station at least part of the transmitted signal (such part herein being called the received signal) reflected from the object, carrying out a frequency modulation of the transmitted signal to produce a frequency difference between the received signal and a correspondingly frequency modulated locally generated signal in a mode such that the magnitude of the frequency difference represents the range of the object from the station, operating upon the received signal with the locally generated signal to produce an indicator signal of said difference frequency providing for range indication, and determining or sensing the angular position of the object with respect to a reference axis extending through the station and the field of view by observation of a characteristic of the indicator signal which is dependent upon the angular position of the object, the improvement comprising:

(a) radiating the stress wave energy into the field of view in the form of a beam,

(b) moving the beam angularly from a datum position occupied at a datum time to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view having angular widths corresponding to that of the beam,

(c) displaying indicator signals derived from the received signals due to these objects in a mode providing an indication of the sector of the field of view in which the beam is located to irradiate each object, by providing sensually perceptible stimuli spaced apart in one dimension in a manner corresponding to the scanning position of the beam, and spaced apart in another dimension in a manner corresponding to the range of the object,

and wherein;

(i) indicator signals of differing frequencies derived from received signals due to objects of different ranges are subjected, before producing the stimuli, to different delays to bring them into coincident time relation at different respective receiving outlets,

(ii) these outlets are subjected to sequential sampling to generate the respective spaced stimuli.

2. A method according to claim 1, wherein:

(a) reception of the received signals is by way of a receiving transducer having a wide angle receptivity characteristic covering the field of view continuously throughout the scanning thereof by the radiated wave energy,

(b) the indicator signals of different frequencies are segregated to different respective receiver outlets by spectral analysis into respective frequency bands,

(c) dwell, or angular transit time, of the beam in, or through, each angular position in the field is at least sufficient for reflections to be received and cause sensually perceptible stimuli from object surfaces at both the inner and outer boundaries of an imaginary annulus having a radial width corresponding to the bandwidth of the respective frequency bands transformed into a distance in the medium irradiated.

3. A method of providing information as to the existence or position of objects otherwise than by direct vision comprising the steps of, radiating stress wave energy (herein called the transmitted signal) from a station to a field of view, receiving at the station at least part of the transmitted signal (such part herein being called the received signal) reflected from the object, carrying out a frequency modulation of the transmitted signal to produce a frequency differing between the received signal and a correspondingly frequency modulated locally generated signal in a mode such that the magnitude of the frequency difference represents the range of the object from the station, operating upon the received signal with the locally generated signal to produce an indicator signal of said difference frequency providing for range indication, and determining or sensing the angular position of the object with respect to a reference axis extending through the station and the field of view by observation of a characteristic of the indicator signal which is dependent upon the angular position of the object, the improvement comprising:

(a) radiating the stress wave energy into the field of view in the form of a beam,

(b) moving the beam angularly from a datum position occupied at a datum time to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view having angular widths corresponding to that of the beam,

wherein;

(i) the display of the indicator signals is effected audibly,

(ii) the indication of the sector of the field in which the object is located is effected by stopping the beam scan at a position at which the indicator signal amplitude is maximised,

(iii) initial approximate determination of object direction is effected by receiving the received signals at transducers providing divergent overlapping polar lobes, and by displaying the indicator signals derived from such transducers respectively binaurally.

4. Apparatus for providing information as to the existence or position of objects otherwise than by direct vision comprising in combination:

(a) a transmitting means for transmitting frequency modulated stress wave energy (herein called the transmitted signal) from a station to a field of view and including transmitting transducer means providing a beam,

(b) means providing a correspondingly frequency modulated locally generated signal,

(c) scanning means for moving the beam angularly from the datum position in the field of view to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view, such sectors having angular widths corresponding to that of the beam,

(d) receiving means at the station for receiving at least part of the wave energy (this part herein being called the received signal) reflected from an object in the field of view,

(e) modulator means for producing an indicator signal at a frequency equal to the frequency difference between the received signal and the locally generated signal, said frequency modulation being in a mode such that the magnitude of the frequency difference is representative of the range of the object from the station,

(f) means for feeding the received signal and the locally generated signal to the modulator means to produce therefrom said indicator signal of said difference frequency,

(g) indicator means responsive to the frequency of said indicator signal to furnish observable range information, and responsive to the angular position of the beam to provide for sensory perception of the sector of the field of view in which the beam is located to irradiate each object,

and wherein

(i) the indicator means comprises coordinate display means providing sensually perceptible stimuli spaced apart in a first dimension in a manner corresponding to the scanning position of the beam, and spaced apart in a second dimension in a manner corresponding to the range of the object,

(ii) the receiving means includes means for segregating the indicator signals, derived from the received signals due respectively to objects of different ranges, to different respective outlets, one for each range band,

(iii) means are provided for subjecting the segregated indicator signals to delays differing in a manner such as to bring the indicator signals into coincident time relation,

(iv) switch means are provided for sampling said outlets successively to feed the indicator signals therefrom to said coordinate display means along said second dimension.

5. Apparatus according to claim 4 wherein:

(a) the coordinate means comprises a cathode ray-tube means,

(b) time base means associated operatively with the cathode ray-tube means and providing for cathode ray beam shift in coordinate directions corresponding to the direction and range of the object,

(c) means operatively connecting said time base means with the scanning means and with the sampling switch means.

6. Apparatus according to claim 4 wherein:

(a) the coordinate display means comprises means providing tactile stimuli and including a plurality of stimulating elements arranged in rows representing different respective range bands, and in columns representing different respective sectors occupied by the beam,

(b) the receiving means includes means for segregating indicator signals, derived from the received signals due respectively to objects of different ranges, to different respective outlets one for each range band, said outlets being connected operatively respectively with said rows of stimulating elements,

(c) said coordinate display means further comprises time base means having an inlet connected to said scanning means and responsive to provide at a plurality of outlets of said time base means signals representing different sectors of beam position said outlets being connected respectively to said columns.

7. Apparatus for providing information as to the existence or position of objects otherwise than by direct vision comprising in combination:

(a) a transmitting means for transmitting frequency modulated stress wave energy (herein called the transmitted signal) from a station to a field of view and including transmitting transducer means providing a beam,

(b) means providing a correspondingly frequency modulated locally generated signal,

(c) scanning means for moving the beam angularly from the datum position in the field of view to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view, such sectors having angular widths corresponding to that of the beam,

(d) receiving means at the station for receiving at least part of the wave energy (this part herein being called the received signal) reflected from an object in the field of view,

(e) modulator means for producing an indicator signal at a frequency equal to the frequency difference between the received signal and the locally generated signal, said frequency modulation being in a mode such that the magnitude of the frequency difference is representative of the range of the object from the station,

(f) means for feeding the received signal and the locally generated signal to the modulator means to produce therefrom said indicator signal of said difference frequency,

(g) indicator means responsive to the frequency of said indicator signal to furnish observable range information, and responsive to the angular position of the beam to provide for sensory perception of the sector of the field of view in which the beam is located to irradiate each object,

and wherein;

(i) the indicator means comprises sound reproducing means providing an audible display,

(ii) the scanning means includes means for stopping the scanning of the beam at a position in which the amplitude of the indicator signal is maximised,

(iii) the receiving means includes

receiving transducer means providing respective divergent overlapping polar lobes,

binaural sound reproducing means,

means defining channels connected respectively between said receiving transducer means and said binaural sound reproducing means.

8. In a method of providing information as to the existence or position of objects otherwise than by direct vision comprising the steps of, radiating stress wave energy (herein called the transmitted signal) from a station to a field of view, receiving at the station at least part of the transmitted signal (such part herein being called the received signal) reflected from the object, carrying out a frequency modulation of the transmitted signal to produce a frequency difference between the received signal and a correspondingly frequency modulated locally generated signal in a mode such that the magnitude of the frequency difference represents the range of the object from the station, operating upon the received signal with the locally generated signal to produce an indicator signal of said difference frequency providing for range indication, and determining or sensing the angular position of the object with respect to a reference axis extending through the station and the field of view by observation of a characteristic of the indicator signal which is dependent upon the angular position of the object, the improvement comprising:

(a) radiating the stress wave energy into the field of view in the form of a beam,

(b) moving the beam angularly from a datum position occupied at a datum time to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view having angular widths corresponding to that of the beam,

(c) displaying indicator signals derived from the received signals due to these objects, said indicator signals including sensually perceptible stimuli spaced apart in one dimension in a manner corresponding to the scanning position of the beam, and spaced apart in another dimension in a manner corresponding to the range of the object, and

(d) compensating for the transit time of the transmitted and received signals in the field of view before display of the indicator signals.

9. A method according to claim 8 wherein compensation for the transit time of the transmitted and received signals comprises:

(a) subjecting those of the indicator signals which are of differing frequencies derived from received signals due to objects of different ranges to respectively different delays substantially to compensate for respective transit times of the wave energy in the field of view out to and back from said objects,

(b) subjecting said indicator signal after said compensation to sequential sampling to generate said stimuli which are spaced apart in a manner corresponding to the respective ranges of said objects.

10. Apparatus for providing information as to the existence or position of objects otherwise than by direct vision comprising in combination:

(a) a transmitting means for transmitting frequency modulated stress wave energy (herein called the transmitted signal) from a station to a field of view and including transmitting transducer means providing a beam,

(b) means providing a corresponding frequency modulated locally generated signal,

(c) scanning means for moving the beam angularly from the datum position in the field of view to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view, such sectors having angular widths corresponding to that of the beam,

(d) receiving means at the station for receiving at least part of the wave energy (this part herein being called the received signal) reflected from an object in the field of view,

(e) modulator means for producing an indicator signal at a frequency equal to the frequency difference between the received signal and the locally generated signal, said frequency modulation being in a mode such that the magnitude of the frequency difference is representative of the range of the object from the station,

(f) means for feeding the received signal and the locally generated signal to the modulator means to produce therefrom said indicator signal of said difference frequency,

(g) indicator means including coordinate display means responsive to respective ones of said indicator signals to provide sensually perceptible stimuli spaced apart in a first dimension in a manner corresponding to the scanning position of the beam and spaced apart in a second dimension in a manner corresponding to the ranges of the object producing said respective indicator signals, and

(h) means for compensating for the transit time of the transmitted and received signals in the field of view before display.

11. Apparatus according to claim 10 wherein:

(a) the receiving means includes means for segregating the indicator signals, derived from the received signals due respectively to objects of different ranges, to different respective outlets, one for each range band,

(b) means are provided for subjecting the segregated indicator signals to differing delays substantially to compensate for respective transit times of the wave energy in the field of view out to and back from said objects in said differing range bands,

(c) switch means are provided for sampling said outlets successively to feed the indicator signals therefrom to said coordinate display means for display spaced apart in said second dimension.

12. Apparatus for providing information as to the existence or position of objects otherwise than by direct vision comprising in combination:

(a) a transmitting means for transmitting frequency modulated stress wave energy (herein called the transmitted signal) from a station to a field of view and including transmitting transducer means providing a beam,

(b) means for providing a corresponding frequency modulated locally generated signal

(c) scanning means for moving the beam angularly from the datum position in the field of view to effect scanning of the field of view successively to irradiate objects contained in successive sectors of the field of view, such sectors having angular widths corresponding to that of the beam,

(d) receiving means at the station for receiving at least part of the wave energy (this part herein being called the received signal) reflected from an object in the field of view,

(e) modulating means for producing an indicator signal at a frequency equal to the frequency difference between the received signal and the locally generated signal frequency modulation of the transmitted and locally generated signal being in a mode such that the magnitude of the frequency difference is representative of the range of the object from the station,

(f) means for feeding the received signal and the locally generated signal to the frequency modulating means to produce therefrom said indicator signal of said difference frequency, and

(g) indicator means responsive to the frequency of said indicator signal to furnish observable range information, and responsive to the angular position of the beam to provide for sensory perception of the sector of the field of view in which the beam is located while irradiating each object, wherein

(h) the receiving means includes receiving transducer means having a wide angle receptivity characteristic covering the field of view,

(i) the receiving means further includes frequency spectrum analyzing means for segregating the indicator signals derived from the received signals due to objects of different ranges to different respective outlets of the receiving means each pertaining to a different respective band of frequencies, and

(j) the scanning means provides for a dwell, or transit time, of the beam in, or through, each of its angular positions in the field, at least sufficient for received signals to be received by said receiving transducer means and cause sensually perceptible stimuli from object surfaces at both inner and outer boundaries of an imaginary annulus having a radial width corresponding to the band width of the respective frequency bands transformed into a distance in the medium irradiated.