System and method for detecting optical signals of a test object that is moved relative to a target

Abstract

The invention relates to a system (100) for detecting optical signals (20) of a test object (10) that is moved relative to a target (50) in the intended test state, wherein the test object (10) has at least one light source (12) for transmitting the optical signals (20), comprising at least one optical receiving unit (30) for receiving the optical signals (20) of the at least one light source (12), wherein the optical receiving unit (30) is designed for digital high-speed data acquisition with pixels addressable in spatially resolved fashion, in particular in the order of microseconds, wherein the at least one light source (12) is oriented towards the optical receiving unit (30), wherein an intensity of the optical signals (20) is encoded in the pixels of temporally successive image recordings by the optical receiving unit (30). The invention further relates to a method of using a system (100) of this kind for detecting optical signals (20) of a test object (10) that is moved in an intended test state.

Description

[0001] Description

[0002] title

[0003] System and method for detecting optical signals from a test object moving relative to a target

[0004] State of the art

[0005] The invention relates to a system for detecting optical signals of a test object moving relative to a target in the intended test state, and to a method for detecting optical signals of a test object moving in an intended test state using a system.

[0006] So-called impactors are used as test objects for impact tests on targets in engine and aircraft structure certification tests. Unlike military projectiles, these test objects are not fired from firearms, but accelerated in acceleration devices such as gas cannons. In these devices, the test objects are brought up to the required speed specified by the authorities for impact with the target.

[0007] Due to the enclosed design of the acceleration devices, it is difficult to measure the acceleration process of the test object. Outside the acceleration device, the test objects are recorded by high-speed cameras up to and beyond the point of impact.

[0008] The test objects are designed to closely resemble real-world flight operations in order to verify passenger safety during the use of the aircraft or helicopter. The test objects are destroyed during testing and their effectiveness cannot be assessed before or after.

[0009] DLR-4352WO

[0010] 2025-11-10 The impact scenarios to be verified are specified by the national aviation safety authorities, e.g. the German Federal Aviation Office (LBA), or the European aviation safety authorities, e.g. the EASA, via the construction regulations (e.g. EASA CS-25 for airplanes and CS-29 for helicopters).

[0011] For soft test objects such as hail (construction standard CS-29.773) and birds (construction standard CS-25.631), the properties are highly dependent on preparation. Both objects, whether artificially produced substitutes in the laboratory or real birds taken from their natural environment, are also research subjects. Currently, only indirect measurements exist, e.g., by measuring the force of impact. Artificial bird models are not yet generally accepted as a substitute for real birds in aircraft certification tests for bird strike testing.

[0012] In hard test objects, it is possible to install a so-called black box, which protects the measurement data recorded in the test objects as effectively as possible during impact, so that the measurement data is available for evaluation after the test. However, the assignment of the measurement data is only possible with proper documentation. Furthermore, the temporal synchronization of the measurement data ideally requires an additional measurement parameter that allows for assignment. This could be, for example, a trigger signal before the measurement begins. However, this also requires a separate connection (wireless / wired). In traditional film, this is achieved, for example, via the clapperboard.

[0013] Wireless connections for transmitting measurement data from the test objects usually require protocols that introduce their own latency. Latency is critical, however, as the test object can be destroyed in as little as 10 milliseconds. Furthermore, the measurement data can only be precisely assigned to specific points through documentation, and the measurement channels must be chosen carefully, otherwise interference between channels can disrupt the transmission.

[0014] DLR-4352WO

[0015] November 10, 2025: Additional latency also means that, in the event of the test object impacting the target, the last data may no longer be transmitted and will be lost. Furthermore, the test itself, for example if the test takes place in the field of high voltage or plasma physics, or other environmental conditions, can render a radio connection unsuitable, unreliable, or even undesirable.

[0016] Alternatively, optical data transmission or camera communication can be used to transmit measurement data from the test objects. Typical applications of camera communication include communication between devices in road traffic or in familiar environments such as offices, factory floors, or private residences. Here, the goal is usually to establish real-time communication, which requires online evaluation of the data stream. However, the data stream from modern high-speed cameras is too large to be evaluated in real time, meaning that in the intended applications, particularly high temporal resolutions and / or large amounts of video data result in a disproportionately expensive system.

[0017] To achieve higher data rates with camera communication, there are also examples of using the so-called rolling shutter effect with a poorly imaged light source. While this increases the achievable data rate, it also increases the demands on the transmission power of the emitting light source. Furthermore, the spatial resolution of the system is significantly reduced, which makes the use of multiple light sources more difficult.

[0018] According to the current state of the art, it is not possible to reliably acquire measurement data from a measuring device on a test object that is completely or partially destroyed during the test. This applies particularly to measuring devices that are accelerated to high speeds and then move through the air and cannot be connected by cables or fiber optic cables.

[0019] Furthermore, depending on the technology used, achieving virtually latency-free acquisition and thus assignment of the measurement data to the parallel-operated measuring device is complex to impossible.

[0020] DLR-4352WO

[0021] 2025-11-10 DE 102020127891 A1 describes a system for optical communication comprising at least one light source for transmitting optical signals, in particular serial optical signals; at least one optical receiving unit for receiving the optical signals from the at least one light source; and at least one mask unit arranged between the optical receiving unit and the at least one light source, which is switchable, at least in certain areas, between a state that is at least partially non-transmitting and a state that is at least partially transmitting. An image of at least one light-emitting area of ​​the at least one light source can be projected onto the at least one mask unit and, in the at least partially transmitting state of the at least one mask unit, can be transmitted to the receiving unit.

[0022] Disclosure of the invention

[0023] The object of the invention is to create an efficient system for capturing optical signals from a test object moving relative to a target in the intended test state.

[0024] Another task is to specify a method for capturing optical signals from a test object moving in a defined test state using such an efficient system.

[0025] The problems are solved by the features of the independent claims. Favorable embodiments and advantages of the invention become apparent from the further claims, the description, and the drawings.

[0026] According to one aspect of the invention, a system for detecting optical signals of a test object moving relative to a target in the intended test state is proposed, wherein the test object has at least one light source for sending the optical signals, comprising at least one optical receiving unit for receiving the optical signals from the at least one light source.

[0027] DLR-4352WO

[0028] 2025-11-10 The optical receiver is designed for high-speed digital data acquisition with spatially resolved addressable pixels, particularly in the microsecond range. At least one light source is directed towards the optical receiver. The intensity of the optical signals is stored in the pixels of successive images taken by the optical receiver.

[0029] The proposed system allows measurement data, as optical signals of a test object moving relative to a target in the intended test state, to be assigned to a high-speed image capture with image accuracy and precise timing.

[0030] The optical signals transmit measurement data from the test object to the optical receiver. The received measurement data can then be extracted from the optical signals and further processed.

[0031] Measurement data from the test object can include, for example, pressure profiles that may be proportional to the damage caused to the target. It is also possible to obtain information about the acceleration and deceleration of the test object. Furthermore, it is possible to capture the test object's serial number in the high-speed recording and assign it to the corresponding measurement data. This improves the documentation of the test performed.

[0032] The image-accurate and time-accurate assignment of the measurement data is made possible by a low latency between a sensor acquisition in the test object and by means of the optical signal, which is digitally encoded, for example, via a microcontroller.

[0033] DLR-4352WO

[0034] November 10, 2025: Using multiple light sources for data transmission is possible to further increase the data rate. However, this has the disadvantage that all light sources must also be read and therefore cannot be arranged arbitrarily close together in order to remain readable. This problem can be countered using adaptive transmission protocols; however, the data rate cannot necessarily be guaranteed in this way.

[0035] The major advantage of this setup lies in capturing the measurement data directly within the image material of a high-speed camera. High-speed cameras are used to capture rapidly moving objects, and the minimized latency offers significant benefits in this context.

[0036] Furthermore, high-speed cameras are used when the risk of damage is accepted. Therefore, it is not guaranteed before the measurement that the data from any accompanying sensors can be recovered afterward. With the proposed system, the measurement data is captured within the high-speed camera itself, which is usually housed in a protected location. Consequently, no additional data acquisition component is typically required. Decoding is performed subsequently using software analysis.

[0037] The detection and transmission electronics are inexpensive, so their loss does not lead to high costs and thus a large number of sensors can be installed.

[0038] The detection and transmission electronics are compact and lightweight, so their influence on the test object and / or the effect of the test object is extremely low.

[0039] The environment surrounding the test object can also be equipped with sensors simultaneously in the same way. This ensures synchronization of the measurement data. If the environment is damaged during the test, similar advantages apply as for the moving test object.

[0040] DLR-4352WO

[0041] 2025-11-10 Even under conditions where there is no threat of destruction, the system can still assign measurements in a simple way with low latency.

[0042] The proposed system can be advantageously used for structural tests, crash tests and impact tests of all kinds, rocket test stands, systems with a high probability of fatal failure, in order to secure measurement data / telemetry, for example in rockets.

[0043] This brings into play both the advantages of the proposed system in the data transmission of moving test objects and in the recording of data from test objects where destruction or at least the risk of destruction is the main focus.

[0044] With a favorable design, the system can be configured for digital and / or analog transmission of the optical signals.

[0045] Due to the high number of optical measurement points, analog measurement methods can transmit an analog-modulated optical signal alongside the digitized signal. This enables a reduction in latency to less than one microsecond. While analog optical signals can thus be used in a simple way, the signal strength in purely analog transmission depends on the light path, for example, due to changes in the distance or tilt of the light source as the transmitting element.

[0046] A combination of analog and digital transmission, for example through prior digitization using an analog-to-digital converter, enables permanent referencing against a calibrated system, namely the analog-to-digital converter.

[0047] With a favorable system design, in the case of analog transmission, the optical signals can be modulated by means of amplitude modulation and / or phase modulation and / or frequency modulation.

[0048] DLR-4352WO

[0049] November 10, 2025 To further improve analog data transmission, additional modulation techniques, such as those known from radio or radar technology, can be used. Examples include amplitude modulation, phase modulation, or frequency modulation. However, this reduces the maximum achievable bandwidth, as the analog signal must be modulated with a carrier frequency.

[0050] With a favorable system design, in the case of digital transmission, the optical signals can be encoded using on-off keying and / or by using a phase and an amplitude of the optical signals.

[0051] A simple method of digital data transmission is so-called on-off keying, which represents binary data using light (on) and dark (off) signals. However, this does not represent an efficient use of the high-speed camera's potential bandwidth. Methods that utilize both phase and amplitude to encode information can be employed more effectively.

[0052] Depending on the system's design, the optical signals can be encoded using quadrature amplitude modulation and / or multicolor coding and / or polarized coding.

[0053] A well-known example of a method that uses both phase and amplitude to encode information is quadrature amplitude modulation, which utilizes both elements. Furthermore, additional data channels can be added through multi-colored or polarized encoding without requiring spatial separation.

[0054] With a favorable design of the system, at least one light source can have an RGB light-emitting diode or be designed as an RGB light-emitting diode.

[0055] DLR-4352WO

[0056] 2025-11-10 The RGB LED can be used, for example, as a light source to capture two digital and one analog channel with a color-sensitive high-speed camera.

[0057] According to a favorable design of the system, the at least one optical receiving unit can have at least one optical element for spatial separation of colors and / or detection of the polarization of the optical signals.

[0058] If the optical receiving unit is not color-sensitive, it is possible to add optical elements that enable spatial separation of the colors. The same applies to their polarization.

[0059] According to a favorable design of the system, the optical signals can have at least two channels, of which at least one channel can be normalized by the other channel of the at least two channels.

[0060] A second channel can be used for normalization. This channel can be a second LED as a light source, a second color, a second polarization, or a specific frequency range.

[0061] Normalization can be performed using either an analog reference level or a digital reference signal.

[0062] A concrete example is analog normalization within a limited frequency range. At a frequency close to the temporal resolution limit of the video recording, a defined modulation, for example 1% of the maximum amplitude, can be transmitted. The analog signal below this frequency can then be referenced to the modulation amplitude and thus normalized.

[0063] DLR-4352WO

[0064] 2025-11-10 According to a favorable system design, the test object can have at least one sensor coupled to at least one light source. Information from the sensor can be encoded in the optical signals.

[0065] Another advantage of optical data acquisition lies in the spatial localization of the light source as the data source. Through the clever arrangement of the sensors and their optical transmitters, the transmitter signals can be easily assigned to the sensor signals without the risk of reversal, which can lead to systematic errors in the evaluation of the measurement data.

[0066] In a favorable embodiment of the system, the at least one sensor can be spatially assigned to the at least one light source and / or connected by an electrical conductor. In particular, the at least one sensor and the at least one light source can be combined in a compact unit.

[0067] The assignment of sensor data to light sources can be ensured, for example, by combining the sensor and optical transmitter as a light source in a compact unit.

[0068] Another option is to connect the sensors and transmitters locally with cables, but to ensure that the transmitter position correlates with the sensor position when arranging them.

[0069] According to a favorable design of the system, a data processing unit can be electrically coupled with the at least one sensor, which is designed to process information from the at least one sensor and to control the at least one light source.

[0070] DLR-4352WO

[0071] 2025-11-10 The data processing unit can, for example, be a microcontroller connected between a sensor and the light source. The microcontroller acquires the sensor's measurement data, processes it further, and uses it to control the light source. The image-accurate and time-accurate assignment of the measurement data is made possible by a low latency between the sensor's acquisition in the test object and the optical signal, which is digitally encoded, for example, by a microcontroller.

[0072] In a favorable embodiment, the system can comprise a further optical receiving unit for receiving the optical signals from the at least one light source, with at least one mask unit arranged between the further optical receiving unit and the at least one light source, and which is configured to be switchable, at least partially, between a state that is at least partially non-transmitting and at least partially transmitting. An image of at least one light-emitting region of the at least one light source can be projected onto the at least one mask unit and, in the at least partially transmitting state of the at least one mask unit, can be transmitted to the further receiving unit.

[0073] In an alternative design, an optical receiving unit with a preceding mask unit (see DE 102020 127 891 A1) can be used additionally, which makes it possible to increase the data transfer rates far beyond the data transfer rates possible with high-speed cameras.

[0074] With a favorable system design, the optical signals can be processed in real time in the further optical receiving unit. In particular, components can be deactivated by means of an interlock.

[0075] This allows for real-time processing of the measurement data, enabling the measurement setup to react dynamically to the measurement results, for example with an interlock that deactivates certain components.

[0076] DLR-4352WO

[0077] 2025-11-10 So-called interlocks are typically used to prevent hazards. Components to be deactivated can include, for example, high-pressure lines or high-pressure tanks, but also sources of high voltage, laser radiation, X-rays, synchrotron radiation, ionizing radiation in general, as well as heating elements, igniters, fuel lines and engines.

[0078] Depending on the system's design, the additional optical receiving unit can be a neuromorphic camera and / or an event-driven camera.

[0079] In order to enable correct mask generation for very fast-moving test objects, a neuromorphic camera or an event-driven camera is a suitable option in addition to the usual camera systems.

[0080] According to a further aspect of the invention, a method for acquiring optical signals from a test object moving in a defined test state is proposed with a system comprising emitting the optical signals with at least one light source of the test object, receiving the optical signals of the at least one light source with at least one optical receiving unit, which is designed for digital high-speed data acquisition with spatially resolved addressable pixels, particularly in the microsecond range; wherein an intensity of the optical signals in the pixels of temporally successive recordings of the optical receiving unit is stored.

[0081] The proposed method allows measurement data, as optical signals from a test object moving relative to a target in the intended test state, to be assigned to a high-speed image with image-level accuracy and precise timing. The optical signals transmit measurement data from the test object to the optical receiver. The received measurement data can then be extracted from the optical signals and further processed.

[0082] DLR-4352WO

[0083] 2025-11-10 The image-accurate and time-accurate assignment of the measurement data is made possible by a low latency between a sensor acquisition in the test object and by means of the optical signal digitally encoded, for example, via a microcontroller.

[0084] Using multiple light sources for data transmission is possible to further increase the data rate. However, this has the disadvantage that all light sources must also be read and therefore cannot be arranged arbitrarily close together in order to remain readable. This problem can be countered using adaptive transmission protocols, but even then, the data rate cannot necessarily be guaranteed.

[0085] The major advantage of this method lies in capturing the measurement data directly within the image material of a high-speed camera. High-speed cameras are used to capture rapidly moving objects, and their minimized latency offers significant benefits. Furthermore, high-speed cameras are employed when the risk of damage is accepted. Therefore, it is not guaranteed that the measurement data from any accompanying sensors can be recovered afterward. With the proposed system, the measurement data is captured within the high-speed camera itself, which is typically housed in a protected environment. Consequently, no additional data acquisition component is usually required. Decoding is performed subsequently using software analysis.

[0086] The environment surrounding the test object can also be equipped with sensors simultaneously in the same way. This ensures synchronization of the measurement data. If the environment is damaged during the test, similar advantages apply as for the moving test object. Even under conditions where there is no risk of damage, the method still allows for the simple and low-latency acquisition of measured values.

[0087] With a favorable design of the process, the optical signals can be transmitted digitally and / or analogously.

[0088] DLR-4352WO

[0089] November 10, 2025: Due to the high number of optical measurement points, analog measurement methods allow for the simultaneous transmission of an analog-modulated optical signal alongside the digitized signal. This enables a reduction of latency to less than one microsecond. While analog optical signals can thus be used in a simple way, the signal strength in purely analog transmission depends on the optical path, for example, due to changes in the distance or tilt of the light source as the transmitting element.

[0090] A combination of analog and digital transmission, for example through prior digitization using an analog-to-digital converter, enables permanent referencing against a calibrated system, namely the analog-to-digital converter.

[0091] With a favorable design of the method, in the case of analog transmission, the optical signals can be modulated by means of amplitude modulation and / or phase modulation and / or frequency modulation.

[0092] To further improve analog data transmission, additional modulation techniques, such as those used in radio or radar technology, can be employed. Examples include amplitude modulation, phase modulation, and frequency modulation. However, this reduces the maximum achievable bandwidth, as the analog signal must be modulated with a carrier frequency.

[0093] With a favorable design of the method, in the case of digital transmission, the optical signals can be encoded using on-off keying and / or by using a phase and an amplitude of the optical signals.

[0094] A simple method of digital data transmission is so-called on-off keying, which represents binary data using light (on) and dark (off) signals. However, this does not represent an efficient use of the high-speed camera's potential bandwidth.

[0095] DLR-4352WO

[0096] 2025-11-10 Methods that use phase and / or amplitude to encode information can be used effectively for this purpose.

[0097] With a favorable embodiment of the method, the optical signals can be encoded using quadrature amplitude modulation and / or multicolored and / or polarized encoding of the optical signals.

[0098] A well-known example of a method that uses both phase and amplitude to encode information is quadrature amplitude modulation, which utilizes both elements. Furthermore, additional data channels can be added through multi-colored or polarized encoding without requiring spatial separation.

[0099] According to a favorable embodiment of the method, optical signals with at least two channels can be used, of which at least one channel is normalized by the other channel of the at least two channels.

[0100] A second channel can be used for normalization. This channel can be a second LED as a light source, a second color, a second polarization, or a specific frequency range.

[0101] Normalization can be performed using either an analog reference level or a digital reference signal.

[0102] A concrete example is analog normalization within a limited frequency range. At a frequency close to the temporal resolution limit of the video recording, a defined modulation, for example 1% of the maximum amplitude, can be transmitted. The analog signal below this frequency can then be referenced to the modulation amplitude and thus normalized.

[0103] DLR-4352WO

[0104] 2025-11-10 According to a favorable embodiment of the method, the test object can have at least one sensor which is coupled to the at least one light source. Information from the sensor can be encoded in the optical signals.

[0105] Another advantage of optical data acquisition lies in the spatial localization of the light source as the data source. Through the clever arrangement of the sensors and their optical transmitters, the transmitter signals can be easily assigned to the sensor signals without the risk of reversal, which can lead to systematic errors in the evaluation of the measurement data.

[0106] According to a favorable embodiment of the method, a data processing unit can be electrically coupled to the at least one sensor, which processes information from the at least one sensor and controls the at least one light source.

[0107] The data processing unit can be, for example, a microcontroller connected between a sensor and the light source. The microcontroller acquires the sensor's measurement data, processes it further, and uses it to control the light source. The image-accurate and time-accurate assignment of the measurement data is made possible by a low latency between the sensor's acquisition in the test object and the optical signal, which is digitally encoded, for example, by a microcontroller.

[0108] DLR-4352WO

[0109] 2025-11-10 According to a favorable embodiment of the method, a further optical receiving unit can receive the optical signals of the at least one light source, wherein an image of at least one light-emitting area of ​​the at least one light source is projected onto at least one mask unit, which is arranged between the further optical receiving unit and the at least one light source and which can be switched back and forth at least partially between a state that is at least partially non-transmitting and at least partially transmitting, and is transmitted to the further receiving unit in the state that is at least partially transmitting of the at least one mask unit.

[0110] In an alternative design, an optical receiving unit with a pre-connected mask unit (see DE 10 2020 127 891 A1) can be used additionally, which makes it possible to increase the data transfer rates far beyond the data transfer rates possible with high-speed cameras.

[0111] With a favorable implementation of the method, the optical signals can be processed in real time in the further optical receiving unit. In particular, components can be deactivated by means of an interlock.

[0112] This allows for advantageous real-time processing of the measurement data, enabling the measurement setup to react dynamically to the results, for example with an interlock that deactivates certain components. Such interlocks are typically used to prevent hazards.

[0113] Components to be deactivated can include, for example, high-pressure lines or high-pressure tanks, but also sources of high voltage, laser radiation, X-rays, synchrotron radiation, ionizing radiation in general, as well as heating elements, igniters, fuel lines and engines.

[0114] drawing

[0115] DLR-4352WO

[0116] 2025-11-10 Further advantages will become apparent from the following description of the drawings. The figures illustrate exemplary embodiments of the invention. The figures, the description, and the claims contain numerous features in combination. It will be advantageous for those skilled in the art to also consider the features individually and combine them into meaningful further combinations.

[0117] They show, for example:

[0118] Fig. 1 a system for detecting optical signals of a test object moving relative to a target in the intended test state according to an embodiment of the invention; Fig. 2 a system for detecting optical signals of a moving test object according to a further embodiment of the invention; Fig. 3 a test object moved by an acceleration device towards a target; and

[0119] Fig. 4 shows a possible test scenario with a test object moved towards an aircraft nose as a target.

[0120] Embodiments of the invention

[0121] In the figures, similar or equivalent components are numbered with the same reference symbols. The figures merely show examples and are not to be understood as limiting.

[0122] The directional terminology used below, including terms like "left," "right," "above," "below," "in front," "behind," "after," and the like, serves only to improve the understanding of the figures and is in no way intended to limit their generality. The components and elements depicted, their interpretation, and their use may vary according to the considerations of a person skilled in the art and be adapted to the specific applications.

[0123] Figure 1 shows a system 100 for detecting optical signals 20 of a test object 10 moving relative to a target 50 in the intended test state according to an embodiment of the invention.

[0124] DLR-4352WO

[0125] 2025-11-10 The test object 10, which can be used as a so-called impactor, for example for impact tests on a target 50 (shown in Figure 2) in tests for engine and aircraft structure approval, has a sensor 14 for recording measurement data.

[0126] The sensor 14 is electrically coupled to a data processing unit 16, for example a microcontroller, which acquires and processes the measurement data from the sensor 14. The data processing unit 16 controls a light source 12 to transmit optical signals 20. Information from the sensor 14 is thus encoded in the optical signals 20. The measured values ​​obtained in this way are then emitted towards the high-speed camera 30 by means of an LED or an equivalent emitter (LED / laser diode / VCSEL).

[0127] The data processing unit 16 can, for example, be a microcontroller connected between the sensor 14 and the light source 12. The microcontroller acquires the sensor's measurement data, processes it further, and uses it to control the light source 12. The image-accurate and time-accurate assignment of the measurement data is made possible by a low latency between the sensor's acquisition in the test object 10 and the optical signal 20, which is digitally encoded, for example, by the microcontroller.

[0128] The optical signals 20 are registered by an optical receiver 30 of the system 100, which is designed for high-speed digital data acquisition with spatially resolved addressable pixels, particularly in the microsecond range. The intensity of the optical signals 20 is thus stored in the pixels of successive recordings by the optical receiver 30. The optical receiver 30 can, for example, be a high-speed camera.

[0129] The light source 12 is aligned towards the optical receiving unit 30, so that the optical signals 20 can be received by the optical receiving unit 30.

[0130] DLR-4352WO

[0131] 2025-11-10 The high-speed camera, acting as an optical receiving unit 30, captures the measurement situation and simultaneously the optically encoded signal 20. In post-processing, the optical signal 20 can thus be precisely assigned to the experimental observation for each individual image.

[0132] The system can be advantageously configured for digital and / or analog transmission of the optical signals 20. The optical signal 20 can be transmitted in analog / digital or mixed form.

[0133] A combination of analog and digital transmission, for example through prior digitization using an analog-to-digital converter, advantageously enables permanent referencing against a calibrated system, namely the analog-to-digital converter.

[0134] In the case of analog transmission, the optical signals 20 can be modulated by means of amplitude modulation and / or phase modulation and / or frequency modulation.

[0135] To further improve analog data transmission, additional modulation techniques, such as those known from radio or radar technology, can be used. However, this reduces the maximum achievable bandwidth, as the analog signal must be modulated with a carrier frequency.

[0136] In the case of digital transmission, the optical signals 20 can be encoded using on-off keying and / or using a phase and an amplitude of the optical signals 20.

[0137] A simple method of digital data transmission is the so-called on-off keying, which represents binary data using light (on) and dark (off).

[0138] DLR-4352WO

[0139] 2025-11-10 Furthermore, the optical signals 20 can be encoded using quadrature amplitude modulation and / or multicolor coding and / or polarized coding. Usable channels are color and polarization as well as position on the test object 10.

[0140] Methods that utilize both phase and amplitude to encode information can be used effectively for this purpose.

[0141] Quadrature amplitude modulation, which utilizes both phase and amplitude to encode information, can be used as a method that takes both elements into account.

[0142] Furthermore, additional data channels can be added through multi-colored or polarized encoding without requiring spatial separation.

[0143] The light source 12 can advantageously have an RGB light-emitting diode or be designed as an RGB light-emitting diode.

[0144] The RGB LED can, for example, be used as a light source to capture two digital and one analog channel with a color-sensitive high-speed camera.

[0145] As shown in dashed lines in Figure 1, the optical receiving unit 30 can have at least one optical element 36 for spatial separation of colors and / or detection of the polarization of the optical signals 20.

[0146] If the optical receiving unit 30 is not color-sensitive, it is possible to insert optical elements in front of it that enable spatial separation of the colors. The same applies to their polarization.

[0147] The sensor 14 can be spatially assigned to the light source 12 and / or connected to an electrical line 18, 19, as is done in the embodiment shown in Figure 1 via the data processing unit 16.

[0148] DLR-4352WO

[0149] 2025-11-10 Another advantage of optical data acquisition lies in the spatial assignment of the light source 12 as the data source. Through the clever arrangement of the sensors 14 and their optical transmitters as the light source 12, the transmitter signals can be easily assigned to the sensor signals without the risk of reversal, which could lead to systematic errors in the evaluation of the measurement data.

[0150] In particular, the sensor 14 and the light source 12 can be combined in a compact unit. This can be especially advantageous in the case of an impactor for impact tests.

[0151] The assignment of sensor data to light sources 12 can be ensured, for example, by combining sensor 14 and optical transmitter as light source 12 in a compact unit.

[0152] Another possibility is to connect the sensors 14 and the light sources 12 locally with cables, as is done in the embodiment in Figure 1 with the lines 18, 19, but to ensure that the transmitter position correlates with the sensor position when arranging them.

[0153] Figure 2 shows a system 100 for detecting optical signals from a moving test object according to a further embodiment of the invention.

[0154] In this embodiment, the system 100 comprises a further optical receiving unit 32 for receiving the optical signals 20 of the light source 12. The further optical receiving unit 32 has a mask unit 34 which is arranged between the further optical receiving unit 32 and the light source 12.

[0155] DLR-4352WO

[0156] 2025-11-10 The mask unit 34 can be switched back and forth, at least partially, between a state that is at least partially non-transmitting and a state that is at least partially transmitting. In this process, an image 38 of the light-emitting area 37 of the light source 12 is projected onto the mask unit 34 and, in the at least partially transmitting state of the mask unit 34, is forwarded to the further receiving unit 32.

[0157] With the additional optical receiving unit 32 with the upstream mask unit 34, the data transfer rates can be increased far beyond the data transfer rates possible with high-speed cameras.

[0158] Advantageously, the optical signals 20 can be processed in real time in the further optical receiving unit 32. In particular, components can be deactivated by means of an interlock. Components to be deactivated can be, for example, high-pressure lines or high-pressure tanks, but also sources of high voltage, laser radiation, X-rays, synchrotron radiation, ionizing radiation in general, as well as heating elements, igniters, fuel lines and engines.

[0159] The measurement setup can advantageously react dynamically to the measurement results through real-time processing of the measurement data.

[0160] As a further optical receiving unit 32, a neuromorphic camera and / or an event-triggered camera can advantageously be used.

[0161] This makes it advantageous to enable correct generation of the mask in the mask unit 34 of the further optical receiving unit 32, even with very fast moving test objects 10.

[0162] Figure 3 shows a test object 10 being moved towards a target by an acceleration device 40. The test object 10 is moved towards the target 50 at high speed.

[0163] DLR-4352WO

[0164] 2025-11-10 The test object 10 is designed as shown in Figure 1. The optical receiving unit 30 is arranged at the level of the exit opening of the acceleration device 40 and detects the optical signals 20 as soon as the test object 10 leaves the acceleration device 40.

[0165] The test object 10 is accelerated in the acceleration device 40, for example a gas cannon, and then flies towards the target 50. In Figure 3, the test object 10 is shown at different times 60, 62, 64 and at different locations 70, 72, 74. At the first time 60, the test object 10 is still in the acceleration device 40. At the last time 64, the test object 10 hits the target 50.

[0166] The rapidly moving test object 10 in the acceleration device 40 is directly visible to the high-speed camera 30 from the moment it exits the device, at time 62, and data from the test object 10 can be transmitted. Data concerning the movement of or from within the test object 10 can be transmitted until its partial destruction, at time 64, or its complete destruction.

[0167] During the flight phase of the test object 10, values ​​for test documentation can already be transmitted, for example, a temperature and / or a serial number of the test object 10. Further data can be captured as image material via the high-speed camera used as an optical receiving unit 30 and can complete the test documentation.

[0168] Target 50 could, for example, be an aircraft nose, which is being tested for safety against test object 10, for example a bird.

[0169] Figure 4 illustrates a possible test scenario with a test object 10 moving towards the nose of an aircraft as target 50. The test object 10 is moved towards target 50 at high speed. Such a test scenario represents a general setup for, for example, bird strike tests.

[0170] DLR-4352WO

[0171] 2025-11-10 The test object 10 is accelerated towards the target 50 by an acceleration device 40, for example a gas cannon, which is operated with a pressurized gas tank 42. A high-speed camera is arranged at a distance in front of the target 50 as an optical receiving unit 30, which receives the optical signals 20 emitted by the test object 10 and simultaneously records images of the impact of the test object 10 on the target 50.

[0172] According to the proposed method, optical signals 20 of the moving test object 10 can be detected by the system 100 by emitting optical signals 20 from at least one light source 12 of the test object 10 and receiving these optical signals 20 from the at least one light source 12 with at least one optical receiver 30, which is designed for high-speed digital data acquisition with spatially resolved addressable pixels, particularly in the microsecond range. The intensity of the optical signals 20 is stored in the pixels of successive recordings by the optical receiver 30.

[0173] The optical signals 20 can be transmitted digitally and / or analogously.

[0174] In the case of analog transmission, the optical signals 20 can be modulated by means of amplitude modulation and / or phase modulation and / or frequency modulation.

[0175] In the case of digital transmission, the optical signals 20 can be encoded using on-off keying and / or by using a phase and an amplitude of the optical signals 20.

[0176] The optical signals 20 can be encoded using quadrature amplitude modulation and / or multicolored and / or polarized encoding of the optical signals 20.

[0177] DLR-4352WO

[0178] Advantageously, the test object 10 can have at least one sensor 14 which is coupled to the at least one light source 12, wherein information from the sensor 14 is encoded in the optical signals 20.

[0179] Advantageously, a data processing unit 16 can be electrically coupled to the at least one sensor 14, which processes information from the at least one sensor 14 and controls the at least one light source 12.

[0180] In a further embodiment, a further optical receiving unit 32 can receive the optical signals 20 of the at least one light source 12. An image 38 of at least one light-emitting area 37 of the at least one light source 12 can be projected onto at least one mask unit 34, which is arranged between the further optical receiving unit 32 and the at least one light source 12 and which can be switched at least partially between a state that is at least partially non-transmitting and at least partially transmitting. In the at least partially transmitting state of the at least one mask unit 34, the image is then transmitted to the further receiving unit 32.

[0181] The optical signals 20 can thus be processed in real time in the further optical receiving unit 32. In particular, components can be deactivated by means of an interlock. Components to be deactivated can be, for example, high-pressure lines or high-pressure tanks, but also sources of high voltage, laser radiation, X-rays, synchrotron radiation, ionizing radiation in general, as well as heating elements, igniters, fuel lines and engines.

[0182] In a possible further test scenario, the target 50 and the system 100 can also move dynamically. The behavior of the test object 10 can then be tested using optical detection of, for example, vibrations and flutter.

[0183] DLR-4352WO

[0184] 2025-11-10 Reference number

[0185] 10 test objects

[0186] 12 light sources

[0187] 14 Sensor

[0188] 16 Data processing unit 18 Line

[0189] 19 Management

[0190] 20 optical signal

[0191] 30 Optical receiving unit 32 Optical receiving unit 34 Mask unit

[0192] 36 optical element

[0193] 37 light-emitting area 38 image

[0194] 40 Acceleration device 42 Compressed gas tank

[0195] 50 Target

[0196] 60 Time

[0197] 62 Time

[0198] 64 Time

[0199] 70 Place

[0200] 72 Place

[0201] 74 Place

[0202] 100 System

[0203] DLR-4352WO

[0204] 2025-11-10

Claims

Claims 1. System (100) for detecting optical signals (20) of a test object (10) moving relative to a target (50) in the intended test state, wherein the test object (10) has at least one light source (12) for transmitting the optical signals (20), comprising at least one optical receiving unit (30) for receiving the optical signals (20) of the at least one light source (12), wherein the optical receiving unit (30) is designed for digital high-speed data acquisition with spatially resolved addressable pixels, in particular in the microsecond range, wherein the at least one light source (12) is directed towards the optical receiving unit (30), wherein an intensity of the optical signals (20) is stored in the pixels of temporally successive recordings of the optical receiving unit (30).

2. System according to claim 1, configured for digital and / or analog transmission of the optical signals (20).

3. System according to claim 2, wherein in the case of analog transmission the optical signals (20) are modulated by means of amplitude modulation and / or phase modulation and / or frequency modulation.

4. System according to claim 2, wherein in the case of digital transmission the optical signals (20) are encoded by means of on-off keying and / or using a phase and an amplitude of the optical signals (20).

5. System according to one of the preceding claims, wherein the optical signals (20) are encoded by means of quadrature amplitude modulation and / or multicolor coding and / or polarized coding. DLR-4352WO 2025-11-10 6. System according to one of the preceding claims, wherein the at least one light source (12) has an RGB light-emitting diode or is designed as an RGB light-emitting diode.

7. System according to one of the preceding claims, wherein the at least one optical receiving unit (30) has at least one optical element (36) for spatial separation of colors and / or detection of the polarization of the optical signals (20).

8. System according to one of the preceding claims, wherein the optical signals (20) have at least two channels, at least one of which can be normalized by the other channel of the at least two channels.

9. System according to one of the preceding claims, wherein the test object (10) has at least one sensor (14) which is coupled to the at least one light source (12), wherein information from the sensor (14) is encoded in the optical signals (20).

10. System according to claim 9, wherein the at least one sensor (14) is spatially assigned to the at least one light source (12) and / or is connected to an electrical line (18, 19), in particular wherein the at least one sensor (14) is combined with the at least one light source (12) in a compact unit.

11. System according to claim 9 or 10, wherein a data processing unit (16) is electrically coupled to the at least one sensor (14), which is configured to process information from the at least one sensor (14) and to control the at least one light source (12). DLR-4352WO 2025-11-10 12. System according to one of the preceding claims, comprising a further optical receiving unit (32) for receiving the optical signals (20) of the at least one light source (12) with at least one mask unit (34) which is arranged between the further optical receiving unit (32) and the at least one light source (12), and which is configured to be switchable at least partially between a non-transmitting and a partially transmitting state, wherein an image (38) of at least one light-emitting area (37) of the at least one light source (12) can be projected onto the at least one mask unit (34) and can be transmitted to the further receiving unit (32) in the at least partially transmitting state of the at least one mask unit (34).

13. System according to claim 12, wherein the optical signals (20) can be processed in real time in the further optical receiving unit (32), in particular wherein components can be deactivated by means of an interlock.

14. System according to claim 12 or 13, wherein the further optical receiving unit (32) is a neuromorphic camera and / or an event-driven camera. DLR-4352WO 2025-11-10 15. Method for detecting optical signals (20) of a test object (10) moving in a test state as intended with a system (100) according to one of the preceding claims, comprising emitting the optical signals (20) with at least one light source (12) of the test object (10), Receiving the optical signals (20) of the at least one light source (12) with at least one optical receiving unit (30) which is designed for digital high-speed data acquisition with spatially resolved addressable pixels, in particular in the range of microseconds; wherein an intensity of the optical signals (20) is stored in the pixels of temporally successive recordings of the optical receiving unit (30).

16. Method according to claim 15, wherein the optical signals (20) are transmitted digitally and / or analogously.

17. Method according to claim 15 or 16, wherein in the case of analog transmission the optical signals (20) are modulated by means of amplitude modulation and / or phase modulation and / or frequency modulation.

18. Method according to any one of claims 15 to 17, wherein in the case of digital transmission the optical signals (20) are encoded by means of on-off keying and / or using a phase and an amplitude of the optical signals (20).

19. Method according to any one of claims 15 to 18, wherein the optical signals (20) are encoded by means of quadrature amplitude modulation and / or multicolor and / or polarized encoding of the optical signals (20).

20. Method according to any one of claims 15 to 19, wherein optical signals (20) with at least two channels are used, at least one of which is normalized by the other channel of the at least two channels. DLR-4352WO 2025-11-10 21. Method according to one of claims 15 to 20, wherein the test object (10) has at least one sensor (14) which is coupled to the at least one light source (12), wherein information from the sensor (14) is encoded in the optical signals (20).

22. Method according to claim 21, wherein a data processing unit (16) is electrically coupled to the at least one sensor (14), which processes information from the at least one sensor (14) and controls the at least one light source (12).

23. Method according to any one of claims 15 to 22, wherein a further optical receiving unit (32) receives the optical signals (20) of the at least one light source (12), wherein an image (38) of at least one light-emitting area (37) of the at least one light source (12) is projected onto at least one mask unit (34), which is arranged between the further optical receiving unit (32) and the at least one light source (12), and which can be switched at least partially between an at least partially non-transmitting and at least partially transmitting state, and is transmitted to the further receiving unit (32) in the at least partially transmitting state of the at least one mask unit (34).

24. Method according to any one of claims 15 to 23, wherein the optical signals (20) are processed in real time in the further optical receiving unit (32), in particular where components are deactivated by means of an interlock. DLR-4352WO 2025-11-10

Images