DE2931837A1 - Orienteering aid for ground navigation features - includes receiver for ultrasonic electromagnetic or infrared signals reflected from object and evaluated by computer - Google Patents

Abstract

The orienteering aid consists of an instrument to determine the distance, direction, size and external surface structure of ground objects (10). It evaluates, converts and transmits the data worked out. It consists of a generator (SG) which transmits a series of oscillations. The signals produced by or reflected from the objects are picked up by a receiver (EV). The signals are evaluated in a computer with an output unit to give the user access to the information. Transmission can be ultrasonic, electromagnetic, or infrared radiation.

Description

The invention relates to a device for determination

the distance, direction, size and surface structure of objects on the one hand and for the evaluation, implementation and output of this determined information on the other hand (guidance).

The block diagram in Figure 1 serves as an explanation.

A transmission frequency generator is controlled by a transmission and evaluation unit AWE SG vibration packets that are emitted by a suitable transmitter transducer will.

The radiated vibrations can, depending on the embodiment of the Invention electromagnetic waves or acoustic waves. The directional characteristic the transmitter transducer used corresponds to the width of the angular range to be recorded to interpret.

The waves emitted are 0 by one or more objects. reflected and received by the receiver transducers EW. Several come, at least however, a receiver transducer to use. They are also embodiments of the invention possible, because the converters serve alternately for sending and receiving.

The time between the transmitted signal and the received signals becomes if the speed of propagation of the waves is known, the distance of the reflecting ones Objects determined. The receiver transducers are spatially separated so that the directions from the time and amplitude relations of the received signals of the objects can be determined. Be in suitable receiver amplifiers EV the received signals are amplified, filtered and used for the subsequent control and evaluation unit AWE processed.

The control and evaluation unit AWE is used to control the transmission frequency generator SG and to influence the gain of the receiving amplifier EV. From the signals from the transmitter generator and the receiver amplifier to the control and evaluation unit arrive, the location coordinates as well as the sizes and surface coarse structures the detected objects are determined and this information is stored.

The subsequent output unit AE calls out the stored data the control and evaluation unit AWE and reshapes them so that they are either for the user of the device acoustically through one or more of his sensory organs, optically, tactilely or electrocutaneously or that they can be perceived in further subsequent Functional units can be processed further.

Compared to other known methods, the one for a leaf orientation aid use a system with subsonic detection (German Pat. 1273830 and 1548479) in the invention described here, the two main functions, namely the acquisition of information about objects as well as information storage on the one hand and information evaluation, -conversion and output on the other hand, each carried out separately.

A pulse sonar resp.

Pulse radar system, as opposed to an FM sonar system mentioned at len other procedures. The output of the determined information can be done here without compromise are optimally adapted to the information absorption capacity with regard to their determination the sensory organs working as receivers such as the human hearing, eye, organs that receive tactile and electrocutaneous stimuli, such as the skin.

The information displayed can be selected by preprocessing so that objects with certain characteristics are particularly emphasized. Even very small objects become safe despite the presence of other larger objects recognizable. By being adapted to the receiving sense organ.

The type of information output is easy and quick to learn using the orientation aid is possible.

The function of an exemplary embodiment is used to explain the invention the orientation aid using the block diagram in Figure 2. Included a transmitting transducer and two receiving transducers are used, preferably work in the ultrasonic range.

In the example chosen, the transmitted tone is derived from the transit time Ultrasonic pulses to objects and back to the receiver transducers cover the distances of these objects.

Correspondingly, the transit time differences become two in the horizontal plane spatially separated receiver transducers the directions of the objects in the horizontal determined.

The strength of the received signals is a measure of the relative size of the objects. Information about the rough surface structure of the objects is obtained Fluctuations of the received signals obtained.

The assemblies in the left part of Figure 2 are used to obtain Information about the objects during the assemblies in the right part of the figure serve for the acoustic display of this information obtained.

A "transmit clock generator" (1) in Figure 2 supplies clock pulses both for controlling a transmission frequency generator (2) as well as for the modules gain control the reception amplifier "(20), fselection of the ranges (10) and" distance measurement " (3). The maximum repetition frequency of the "transmit clock generator (1) is due to the greatest Distance from which signals from objects can still be received and from the corresponding transit time of these signals from the transmitter to the objects and to the receivers given back. The "transmission frequency generator" (2: generates with every control pulse of the "transmission clock generator" (1) a short oscillation packet. These vibrations will amplified in the "output stage" (4) and emitted by the "transmitting transducer" (5).

the "Receiver" transducers <6) receive signals from the objects, preferably reflections of the transmitted vibration packets.

The "receiving amplifiers n (8)" are connected to the receiving transducers used adapted and are used in the Ortngsverfahren used here with ultrasonic pulses constant carrier frequency designed frequency-selective, so that in contrast to one broadband receiver arrangement interference signals can be largely suppressed. Signals as well as superimposed noise disturbances whose amplitude is below a fixed or variable threshold values are known by appropriate known circuit measures be suppressed. The gain of the receiving amplifier can either be timed constant on or with increasing time interval to the transmission signal by the assembly "Gain control of the receiving amplifiers" (20) are continuously increased, to include weak signals from objects that are further away, despite greater attenuation to be able to evaluate.

During the transmission process itself, gain control is carried out via the assembly the receiving amplifier "(20) the receiving amplifier blocked to crosstalk of the transmission signal in the receiving channels ineffective. Additionally is also an automatic gain control of the receiving amplifier depending on the amplitude of the signals received in each case.

In the module logical link (9) are made from the received Signals Control signals for the modules nDistance measurement "(3), direction measurement" (12), "amplitude measurement" (21) and the corresponding memory modules "memory for the distance "(11), $" memory for the direction "(13) and memory for amplitudes (22) won. Depending on the range set in the "Choice" module the range (10) only signals within a corresponding period of time evaluated according to the transmission signal. It is also possible to only send signals after a certain period of time after the Senc: sslgnal are received, so that the display of very close, possibly permanent objects is prevented.

The "Distance measurement" module (3) depends on the duration there is a time and thus distance proportional between the transmission signal and the received signals Size is formed and the instantaneous value of this for each incoming reception signal Size stored in corresponding n memories for distance (11). These sizes can be electrical voltages or charges or the respective states of digital Be counters.

The measurement of the direction from which signals arrive at the receivers can be used as a time difference measurement or phase difference measurement between the signals Carry out "direction measurement" (12) from the two receiving amplifiers in the module. If the time or phase difference is zero, the corresponding object is located on the plane of symmetry between the two receivers. The time differences will be in measuring devices that correspond to those for the time measurement between transmission and received signals in the "distance measurement" block (3) are determined and stored in suitable storage elements in the "memory for directions" (13). The same applies to the phase measurement and its storage. In another Training of the invention can also aun the differences in amplitude of the signals the directions of the objects can be determined for both receivers.

The amplitude of the reception signals depends on the distance and the size of the detected objects. In the module amplitude measurement "(21) the amplitudes of the received signals are determined as analog or digital quantities and stored in suitable n memories for amplitudes "(22).

A possibly variable gain of the "receiving amplifier" (8) pnfd taken into account in the amplitude measurement.

To record the information about several objects, the corresponding Number of storage options to be provided.

With each new cycle, starting with the pulse of the "send clock generator" (1), the current values of the distances, directions and sizes are used of objects determined and stored. Fluctuations in these quantities due to the coarse surface structure of the objects, appear as corresponding fluctuations of the saved values. By comparing the saved values with the previous @ Cycles, information about the rough surface structure can be extracted and get to further evaluation.

The evaluation and output of the determined and stored information can be done in different ways.

In the embodiment described here, an acoustic Display selected. In other embodiments of the invention, however, optical, tactile, electrocutaneous or other displays as well as further evaluation, for example, to control or brake vehicles, as well as co-nations thereof possible.

A "query clock generator" (14) ensures that the stored Information according to various criteria regarding distance, direction, size and number of objects from the "save for distance" (11), "save for direction" (13) and "Save for amplitudes" (22) depending on the number of to be displayed Objects that are entered in the assembly "Number of objects (15). Should several Objects are displayed, takes place in the embodiment described here the display is serial and cyclical. Starting with the closest object in distance the other objects are displayed in the order in which they are displayed by the increasing distance of the objects is given. The individual display itself takes place in the embodiment described here acoustically according to the following statements.

The information about the distance of the objects is used for control the frequency of a "low frequency generator (t6) * The frequency is proportional increased to the determined and displayed distance. This assignment is therefore useful, because, according to measurements from psychoacoustics, the human hearing expands a lot Pitch range can perceive what a very large representable distance range is equivalent to. In addition, the pitch changes just perceptible by the ear are in lower frequency ranges less than in high frequency ranges, so that with the selected Assignment the differentiation of small differences in distance or changes in distance is particularly good at short distances. From psychoacoustic measurements it is also known that low frequencies, which are used here to display nearby objects, are less likely to be obscured by background noise than high frequencies.

The vibrations generated in the 8'Nitderfrequenzgeneratort '(16) can be sinusoidal. In psychoacoustic experiments, however, it has proven to be very useful revealed to choose vibrations with strong harmonic content. For example allow square or triangular waves due to their proportion of harmonics a much more exact directional estimation through interaural @level differences the beidohri, presented sound. as well as better pitch perceptibility at low frequencies.

In addition, the retrieved distance information is also used for influencing the duration of the generated low frequency tone pulses in the assembly durations (23). the So tunes are not presented as a continuous signal, but as sound impulses, whereby the duration = Nt of decreasing distance of the objects and thus decreasing frequency of the Low frequency generator anetsigt.

Results from psychoacoustics show that the threshold of perception for differences or changes in sound when varying several sound parameters at the same time smaller than nrd than when only one parameter is varied. Through the described With the choice of assignments, the acoustic indicators of nearby objects are better and more reliable perceptible as the second removed object.

Because the tone pulse durations become shorter and shorter as the distance increases but the pause between the tone impulses is kept constant, The repetition rate of the tone impulses also increases with increasing distance.

Depending on the determined variables, the "amplitude modulation" module (25) the amplitudes of the low frequency vibrations used for display varies. Appropriate dimensioning of the variation range ensures that that the display of the smallest detected object is reliably audible.

After by abruptly switching on and off ler low frequency signals a very wide frequency spectrum is generated and this is very annoying for the hearing is felt, the amplitudes of the negative frequency pulses in the assembly "Envelope" (17) provided with a time envelope.

According to paychoacoustic measurements, increase or decrease

Fall times in the range of a few milliseconds are very favorable. The envelope can also be defined by the periods of the low frequency oscillations themselves can be controlled, eo that the amplitude increases more slowly at low frequencies than at high frequencies.

In the "direction modulation" assembly (18), the frequency signal is never used so modulated in amplitude that the level difference between the two output signals can be influenced by the stored and retrieved directions of the objects. Corresponding measurements from psychoacoustics show that a level difference of a maximum of t 24 dB is sufficient around the perceived direction of the sound, the two ears are presented to assume all values between "far left" and "far right" permit.

In addition to varying the level differences between the two Output signals can be set depending on the stored and retrieved directions of the detected objects also phase or time differences between the two output signals produce. This makes the direction to be displayed easier to see, small differences in direction, or changes are acoustically more perceptible.

In the two "low frequency amplifiers" (19) the low frequency signals amplified to the extent that they are from the "headphone systems" (7) with a sufficient sound pressure level can be radiated. The frequency transmission ratio of the low frequency amplifiers is designed so that deviations of the "headphone systems" (7) used from the constant frequency-independent free field transmission factor are approximately compensated. In particular, the deep frequencies also become the same in accordance with the "curves Volume (ISO - Rec. 226) increased so that it is as loud as the higher frequencies appear.

The "headphone systems" (7) used are preferably constructed in such a way that that existing ambient noise without significant shielding to the ear d3s user the orientation aid. Due to its design, the headphones must be in be able to emit ink frequencies sufficiently strong.

To make it easier to estimate the absolute distance, you can optionally with the aid of the "Reference distance" assembly (24), the display of one or more known distances can be simulated and the display of the actual distance be compared with it. Appropriate measures can also make the assessment the direction and size of objects can be facilitated.

Serves a battery or an accumulator as an energy source for the device 50 described can also take appropriate measures to increase the state of charge the existing display front directions are signaled.

; Other options for training the invention: In further training of the invention are used instead of ultrasound to determine the positions of Objects electromagnetic waves or optical signals, preferably in the infrared range used.

The transmitter and receiver transducers used have in one or two perpendicular to the main beam direction bs direction of maximum sensitivity standing axes have a wide directional characteristic, thus from a large solid angle Information can be determined. The converters can alternate as transmitters and receivers are operated. There will be at least one transmitter (encoder) and two Locally separate receivers used to show the directions of objects in a plane to investigate. If the location coordinates of objects are to be determined in more planes, several converters are to be provided.

The transmitter and receiver transducers used can be selected by the user of the Orientation aid to be held in the hand, on a headgear or the Chalk or be mounted on a glasses frame. Also is the mounting on a corresponding bracket is possible only slightly on a conventional one Spectacle frame can be attached. The transmitter and receiver transducers can also be used be attached to land or water vehicles or stationary objects.

In a further embodiment of the invention, the received signals or their envelopes or parts thereof in suitable analog or digital storage devices to be available for further processing.

For the acoustic display, depending on the distance to be used, can be used the frequency, duration, repetition rates, spectral composition, envelopes and The level of the audible sound used can be influenced, including combinations the parameter variations described are possible. Depending on the determined The size of the objects is the level, the duration, the frequency spectrum or combinations influenced by the sounds used for display.

The envelope of the sound used for the display can also pass through the determined information about the objects can be influenced. The ads of several Objects can either be carried out serially and cyclically as in the example described or in parallel.

The overall level of the display can depend on the noise level in the area has been varied.

Claims (58)

Claims: The invention relates to an orientation aid, characterized by a transmitter which emits vibration packets, at least one Receiver preferably originating from objects or receiving reflected signals and a converting evaluation unit for the signals contained in the received signals Information and an output unit to make the information accessible to the user close. 2. Orientation aid according to claim 1, characterized in that Transmitter and receiver suitable for the transmission or reception of ultrasound are. 3. Orientation aid according to claim 1, characterized in that Transmitter and receiver for the transmission or reception of electromagnetic Waves are suitable. 4. Orientation aid according to claim 1, characterized in that Transmitter and receiver for the transmission or reception of waves in the infrared range are suitable. 5. Orientation aid according to one or more of claims 1 to 4, characterized in that the donors and Empenger used in one or two perpendicular to the main beam direction or the direction of maximum sensitivity vertical axes have a wide directional characteristic. 6. Orientation aid according to one or more of claims 1 to 6, characterized in that a transducer alternately as a transmitter or receiver is operated. 7. Orientation aid according to one or more of claims 1 to 6, characterized in that at least one encoder and two or more spatially separate receivers can be used. 8. Orientation aid according to one or more of claims 1 to , ', characterized in that the transmitter and receiver used on the glasses frame, Headgear or clothing worn by the user or held in the hand. 9. Orientation aid according to one or more of claims 1 to 8, characterized in that the transducers are mounted on a bracket in such a way that that they can easily be attached to a conventional spectacle frame. 10. Orientation aid according to one or more of claims 1 to 7, characterized in that the donors and receivers used are on a land or watercraft are attached. 11. Orientation aid according to one or more of claims 1 to 7, characterized in that the transmitter and receiver used on stationary Objects are attached. 1 2. Orientation aid according to one or more of claims 1 to 11, characterized in that the donor or donors compared to the pause duration emit short vibration packets with a time interval that is at least twice that Running time of the signals up to the maximum desired distance within the objects are to be detected, corresponds. 13. Orientation aid according to one or more of claims 1 to 12, characterized in that the distances of reflective objects from the Transit times of the emitted waves between the time of transmission and the arrival of the reflections can be determined at the recipients. 14. Orientation aid according to one or more of claims 1 to 13, characterized in that information is obtained from the strength of the reflections received determined by the size of the reflecting objects, depending on their distance will. 15. Orientation aid nac1 one or more of claims 1 to 14, characterized in that only signals received within a certain period of time after the transmission signal are received, corresponding to a certain distance range> can be used for measuring the distance of objects. 16. Orientation aid according to one or more of claims 1 to 15, characterized in that only signals after a certain purely Minimum distance after the transmission signal is received, further processed. 17. Orientation aid according to one or more of claims 1 to 16, characterized in that when using several @ mpfänger from the amplitudes the received signals from objects the sizes of these objects can be determined. 18. Orientation aid according to one or more of claims 1 to 17, characterized in that when using several receivers from the time or phase differences and / or amplitudes differed in the received signals of objects the directions of these objects can be determined. 19. Orientation aid according to one or more of claims 1 to 18, characterized in that information about the rough surface structures of the objects from fluctuations in the signals received from these objects within one or more sampling periods are determined. 20. Orientation aid according to one or more of claims 1 to 19, characterized in that the gain of the received signals is dependent is varied by the time after the transmission of the vibration packet. 21. Orientation aid according to one or more of claims 1 to 20, characterized in that the gain of the received signals depends is varied by their respective strength. 22. Orientation aid according to one or more of the An, p, a'd, 6 1 to 21, characterized in that only received signals that have a fixed or variable Exceed the threshold value, proceed to further evaluation. 23. Orientation aid according to one or more of claims 1 to 22, characterized in that the distance measurement according to claim 13 by means of a clock generator and a digital counter takes place, and that with each incoming Signal of an object, the respective counter reading is transferred to a suitable memory will. 24. Orientation aid according to one or more of claims 1 to 23, characterized in that the distance measurement according to claim 13 by means of a time-dependent electrical analog value takes place, and that with each incoming Signal of an object, the respective electrical size is transferred to a suitable memory will. 25. Orientation aid according to one or more of claims 1 to 24, characterized in that the received signals or their envelopes or parts of which are taken over into suitable analog or digital storage and from there to further processing can be read out. 26. Orientation aid according to one or more of claims 1 to 25, characterized in that the directions of the detected objects by measurement the mutual temporal relations of the received signals from several spatially separate receivers by suitable analog or digital working circuits he follows. 27. Orientation aid according to one or more of claims 1 to 25, characterized in that the directions of the detected objects by measurement the mutual amplitude relations of the received signals from several spatial separate receivers by suitable analog or digital working circuits he follows. 28. Orientation aid according to one or more of claims 1 to 27, characterized in that the determined directions of the objects in suitable Storage devices are stored. 29. Orientation aid according to one or more of claims 1 to 28, characterized in that the evaluation and output of the determined information takes place independently of the acquisition of the information via the detected objects. 30. Orientation aid according to one or more of claims 1 to 29, characterized in that from the stored information about the detected Objects one or more physical parameters of stimuli are varied the user of the device according to the invention can perceive. 31. Orientation aid according to one or more of claims 1 to 30, characterized in that the information ascertained on the acquired Objects are used to control or influence other devices. 32. Orientation aid according to one or more of claims 1 to 30, characterized in that the stored information is output so that the user can detect them tactilely or electrocutaneously. 33. Orientation aid according to one or more of claims 1 to 30, characterized in that the stored information is output so that they can be visually recognized by the user. 34. Orientation aid according to one or more of claims 1 to 30, characterized in that the stored information is output so that the user can detect them acoustically. 35. Orientation aid according to one or more of claims 1 to 34, characterized in that the frequency is more audible and used for display Sounds is influenced by the distances of the detected objects. 36. Orientation aid according to one or more of claims to 35, characterized in that the durations of audible and used for display tone pulses can be influenced by the distances of the detected objects. 37. Orientation aid according to one or more of claims 1 to 36, characterized in that the repetition rates of audible and for display Tocimpulses used can be influenced by the distances of the detected objects. 38. Orientation aid according to one or more of claims 1 to 37, characterized in that the frequency spectra of the audible and for display used sound signals are influenced by the distances of the detected objects. 39. Orientation aid according to one or more of claims 1 to 38, characterized in that the levels of the audible sound used for display can be influenced by the distances of the detected objects. 40. Orientation aid according to one or more of claims 1 to 39, characterized in that combinations of different sound parameters of the audible sounds used to display the distances of the objects being detected to be influenced. 41. Orientation aid according to one or more of claims 1 to 40, characterized in that the interaural level differences of the two ears presented audible sounds used for display from the directions of the detected Objects are influenced. 42. Orientation aid according to one or more of claims 1 to 41, characterized in that the interaural envelope curve differences of the two ears presented audible sounds used for display from the directions of the detected Objects are influenced. 43. Orientation aid according to one or more of claims 1 to 42, characterized in that the interaural phase differences of the two ears presented audible sounds used for display from the directions of the detected Objects are influenced. 44. Orientation aid according to one or more of claims 1 to 43, characterized in that combinations of several interaural differences of the sounds presented on both ears and used for display from the directions of the affected objects. 45. Orientation aid according to one or more of claims 1 to 44, characterized in that the level of the sound used for display of the size of the detected objects is influenced. 46. Orientation aid according to one or more of claims 1 to 45, characterized in that the duration of the sound pulses used for display can be influenced by the size of the detected objects. 47. Orientation aid according to one or more of claims 1 to 46, characterized in that the frequency spectra of the sounds used for display can be influenced by the size of the detected objects. 48. Orientation aid according to one or more of claims 1 to 47, characterized in that the envelopes of the tone pulses used for display have a finite rise and / or fall time. 49. Orientation aid according to one or more of claims 1 to 48, characterized in that the rise and / or fall times of the envelope curves the sounds used to display the information collected and queried can be influenced via the objects. 50. Orientation aid according to one or more of claims 1 to 49, characterized in that the output of the information of several objects after various criteria regarding their distances, directions, sizes and numbers he follows. 51. Orientation aid according to one or more of claims 1 to 50, characterized in that the information output is in each case in the shortest Distance to the object is limited. 52. Orientation aid according to one or more of claims 1 to 51, characterized in that only one information output about objects in one certain distance and / or angle range takes place. 53. Orientation aid according to one or more of claims 1 to 52, characterized in that the information output via several objects in cyclically repeating, serial sequence takes place. 54. Orientation aid according to one or more of claims 1 to 53, characterized in that the information output over several objects in time takes place in parallel. 55. Orientation aid according to one or more of claims 1 to 54, characterized in that the overall volume of the used for display Sound is influenced by the strength of the ambient noise. 56. Orientation aid according to one or more of claims 1 to 55, characterized in that optionally to display the information of the detected Objects the display of known reference distances or reference directions takes place. 57. Orientation aid according to one or more of claims 1 to 56, characterized in that the headphone systems used for acoustic display their design does not prevent the perception of ambient noise. 58. Orientation aid according to claim 48, characterized in that the envelopes of the low frequency oscillation used for the display by electronically Switched voltage divider is generated, the electronic switch through Signals are controlled, which are obtained from the low frequency vibration.