Test system with acoustic noise reproduction through hybrid simulation

Abstract

A system and method for use with a testing machine 10 having an actuator 22 for applying a load or displacement to a test specimen 13. The system and method includes sensors 18, 24 operatively coupled to the test specimen 13 to sense motion or force and provide sensor output signals 48A, 48B. A signal conversion processing circuit 54 coupled to receive the sensor output signals and configured to provide an output signal 56 related to the audible and / or inaudible acoustic range of the test specimen 13 and virtual components coupled to the test specimen 13. Output devices 62, 64 coupled to receive the output signals related to the audible and / or inaudible acoustic range and to render information related to vibrations generated by the test specimen 13 and virtual components coupled to the test specimen 13.

Description

[Background technology]

[0001] The following discussion is provided for general background information only and is not intended to be used as an aid in determining the scope of the claimed subject matter.

[0002] Within the field of vehicle testing, there is a subfield called noise, vibration, and harshness (NVH). NVH is the study of undesirable disturbances to vehicle occupants in the form of mechanical vibrations, acoustic noise, and harsh impacts. These noises can be generated from the road, ambient airflow, engine, motor mounts, shock absorbers, and other sources. For example, in the case of shock absorbers (also known as dampers), acoustic noise can be subdivided into acoustic noise directly derived from the shock, such as friction-induced squeals, and noise often referred to as "swish," which often originates from oil flow within the damper. Another damper-derived noise phenomenon is structure-born noise, which arises as mechanical vibrations from within the shock body itself. Structural vibrations are then radiated from the damper body into the damper rod and further toward the upper shock absorber mount. Near (or sometimes at some distance from) the connection between the damper rod and the chassis structure, this mechanical vibration then transforms into acoustic noise.

[0003] For example, in the field of damper NVH testing, the airborne noise emitted directly from a shock absorber is well understood and easily reproduced and identified on a damper load frame through laboratory component testing. This testing consists of measuring the acoustic noise with a microphone and moving the damper body with a batch of displacement waveforms known to accentuate the acoustic noise emission. However, in the field of NVH damper testing, the structure-borne sound path, often referred to as the "chuckle," is much more difficult to reproduce and identify on a component test load frame in the laboratory. There are many reasons why this is the case. Some of the main reasons are that the load frame introduces disturbances that perturb the measurements. Also, typical damper test measurements are low-frequency measurements (<50 Hz), whereas for specialized NVH testing, high-frequency measurements are required due to the high frequency of the chuckle frequency component (>100 Hz). Yet another reason is that the true impedance of the surrounding structure coupled to the damper rod is not adequately reproduced in a load frame mockup. Also, for example, measurement data (accelerations and forces) from vibration tests aimed at fatigue testing of dampers do not directly represent the desired acoustic phenomenon. More specifically, it is desirable to identify the source and presence of acoustic noises that are normally audible, but which may be inaudible in some circumstances, but fatigue tests and measurements do not address this phenomenon.

[0004] It is desirable to have a testing machine that can reproduce this phenomenon of acoustic noise from a test specimen and components coupled to the specimen for purposes of subjective investigation and / or quantitative analysis. The acoustic noise may include, but is not limited to, "chuckle." This noise may be audible and / or inaudible. Summary of the Invention

[0005] This summary is provided to introduce some concepts in a simplified form. These concepts are further described below in the detailed description. This summary is not intended to identify key features, essential features, or all features of the invention. Moreover, the description and claimed subject matter provided herein should not be construed as intended to address any of the shortcomings discussed in the background.

[0006] One or more computerized systems can be configured to perform particular operations or actions by installing software, firmware, hardware, or a combination thereof on the system that causes the system to perform the actions during operation. One or more computer programs can be configured to perform particular operations or actions by containing instructions that, when executed by a data processing device, cause the device to perform the actions.

[0007] A system and method for use with a testing machine having an actuator for applying a load or displacement to a test specimen, the system and method including a sensor operatively coupled to the test specimen to sense motion or force and provide a sensor output signal, a signal conversion processing circuit coupled to receive the sensor output signal and configured to provide an output signal related to an audible acoustic range and / or an inaudible acoustic range of the test specimen and a virtual component coupled to the test specimen, and an output device coupled to receive the output signal related to the audible acoustic range and / or the inaudible acoustic range and to render information related to vibrations generated by the test specimen and the virtual component coupled to the test specimen.

[0008] Another aspect is a method in which obtaining the signal transformation processing relationship can include obtaining a finite element analysis model of the test specimen and the component coupled to the test specimen, and performing harmonic analysis on the finite element analysis model to obtain the signal transformation processing relationship. Obtaining the signal transformation processing relationship can include obtaining a finite element analysis model of the test specimen and the component coupled to the test specimen, and performing a virtual transfer path analysis on the finite element analysis model to obtain the signal transformation processing relationship. Obtaining the signal transformation processing relationship can also include constructing the test specimen and the component coupled to the test specimen, moving and / or applying a force to the test specimen, measuring vibrations in the test specimen and / or the component coupled to the test specimen, and performing a transfer path analysis using the measured vibrations to obtain the signal transformation processing relationship. Implementations of the described techniques can include hardware, methods or processes, or computer software on a computer-accessible medium.

[0009] Another aspect is a testing system including a base, at least one pair of struts connected to the base, and a crosshead connected to the struts at a location spaced from the base. At least one pair of specimen holders is provided, including a first specimen holder supported by the crosshead and facing the base, and a second specimen holder supported by the base, the base being connected to each of the struts closest to the crosshead. An actuator is connected in series between one of the specimen holders and the corresponding base or crosshead. The system also includes a sensor operably coupled to the specimen for sensing movement or force and providing a sensor output signal. A signal conversion and processing circuit is coupled to receive the sensor output signal and configured to provide an output signal related to the audible and / or inaudible acoustic ranges of the specimen and a virtual component coupled to the specimen. An output device is coupled to receive the output signals related to the audible acoustic region and / or the inaudible acoustic region and to render information related to the vibrations generated by the test specimen and the virtual component coupled to the test specimen. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the above methods.

[0010] Implementations of the above-described aspects may include one or more of the following features: The output device may include a speaker to provide a generally subjective noise to the user, and additionally or alternatively, the output device may include a module for visually rendering the output signal. As will be appreciated by those skilled in the art, the signal conversion and processing circuitry may include analog circuitry and / or a processor coupled to a memory configured to store values ​​indicative of the sensor output signal and to store instructions configured to process the stored values ​​to generate the output signal related to the acoustic field of a test strip and a virtual component coupled to the test strip. The processor and instructions may include a digital filter. The output signal may be generated substantially in real time relative to the sensor output signal or may be generated non-real time relative to receipt of the sensor output signal. Implementations of the described techniques may include hardware, methods or processes, or computer software on a computer-accessible medium. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 2 is a side view of the testing machine.

[0012] [Figure 2] FIG. 1 is a schematic illustration of a process control loop that controls the operation of a test machine.

[0013] [Figure 3] FIG. 2 is a block diagram illustrating certain components of a computing device.

[0014] [Figure 4] FIG. 1 is a block diagram illustrating the processing of sensor signal(s) from a test machine. DETAILED DESCRIPTION OF THE INVENTION

[0015] A schematic diagram of an exemplary testing machine 10 for applying force or motion to a test specimen 13 (such as, but not limited to, a damper, shock, motor mount, etc.) is shown in FIG. 1. The testing machine includes a frame 11 having a base 12, a pair of columns 14 extending upwardly from the base 12, and a crosshead 16 joined to two of the columns 14 at spaced locations from the base 12. At least one pair of specimen holders 20A, 20B is provided. A first specimen holder 20A is supported by the crosshead 16 and extends toward the base 12. A second specimen holder 20B is supported by the base 12 and extends toward the crosshead 16. It should be noted that the base 12 is the portion of the testing machine 10 joined to each of the columns 14 closest to the crosshead 16.

[0016] An actuator 22 is connected in series between one of these specimen holders 20A, 20B and the corresponding base 12 or crosshead 16. In the embodiment shown in FIG. 1, the first specimen holder 20A is attached to a force transducer 24 supported by the crosshead 16, while the second specimen holder 20B is coupled to an actuator 22 in the base 12. It should be noted that in another embodiment shown in FIG. 2, the actuator 22 is located on the crosshead 16, while the force transducer 24 is then attached to the base 12.

[0017] A control system, described below, controls the operation of actuator 22 based on a desired test profile to be applied to test specimen 13. While a desired force and / or motion is applied to test specimen 13, feedback can be provided from appropriate sensors, such as force transducer 24 and / or motion sensors, such as displacement sensors, velocity sensors, or accelerometer 28 shown herein. As will be appreciated by those skilled in the art, any of the motion sensors described above can be used with appropriate processing to obtain a desired parameter indicative of motion. This parameter is typically acceleration, although this should not be considered limiting. In the illustrated embodiment, accelerometer 28 is typically coupled to the end of test specimen 13 for convenience, although such placement or location should not be considered limiting.

[0018] The actuator 22 is typically an electromagnetic linear actuator in that it should be capable of achieving high fidelity in motion and applied force. One suitable actuator is described in U.S. Patent Application Publication No. 20210108998, U.S. Patent Application No. 17 / 069,498, filed October 13, 2020, entitled "ELECTRIC ACUATOR," which is incorporated herein by reference in its entirety. However, no specific configuration should be considered required for all applications. While electric actuators are well suited for the tests described herein, servohydraulic actuators may be suitable depending on the specimen being tested and the acoustic information desired, and therefore, servohydraulic actuators can also be used if desired.

[0019] It is further desirable that the load frame 11 should be sufficiently rigid so as not to impede the acoustic information being acquired and, therefore, not to affect or attenuate the desired acoustic information being acquired. U.S. Patent Application Publication No. 20210215587, U.S. Patent Application No. 17 / 148,267, filed January 13, 2021, entitled "TESTING SYSTEM WITH COLUMN BRACE," describes bracing that can be added to a testing machine to improve stiffness, and can be used if desired. This U.S. patent application is incorporated herein by reference in its entirety.

[0020] 3 illustrates a control system for the testing machine 10, generally including a computing device 21, a system controller 23, and a servo controller 26. The computing device 21 allows a user to interact with and / or control the testing machine 10, while the system controller 23 controls the servo controller 26 based on the test being performed. The servo controller 26 provides actuator command signals 19 to controlled devices 25 (e.g., servo valves, servo drives, power controllers) to operate actuators 22 (located in this embodiment on the crosshead 16), which in turn stimulate the test specimen 13. It should be noted that the controller 26 and controlled devices 25 are of a design appropriate for controlling the type of actuator being used. Appropriate feedback 15A can be provided to the controller 26 from the actuators 22 or other sensors. One or more remote transducers, such as displacement sensors, strain gauges, accelerometers, load cells, thermometers, microphones, cameras, etc., on specimen 13, and / or actuator 22, and / or specimen supports 20A, 20B, and / or support frame 11, provide measured or actual response 21B. In an exemplary embodiment, load cell 24 also provides response 21A. System controller 23 may also receive actual response 21B as feedback in response to drive 17 as an input to servo controller 26. In the illustration of FIG. 2, signal 17 is the reference signal, signal 19 is the manipulated variable (command to the device being actuated), and signal 15A is the feedback variable. While a single-channel case is shown in FIG. 2, a multi-channel embodiment having signal 15A with N feedback components and signal 19 with M manipulated variable components may also exist and be considered an alternative embodiment of the present invention. Typically, the types of loads that can be applied or exerted on the test specimen 13 include tension, compression, and / or torsion in one or more degrees of freedom, applied separately or simultaneously, typically through separate actuators.Additionally or alternatively, the test specimen 13 may be subjected to controlled displacement in one or more degrees of freedom, applied separately or simultaneously.

[0021] The computing device 21, the system controller 23, and the controller 26 can each be implemented in digital and / or analog computers or circuitry. FIG. 3 and the associated discussion provide a brief, general description of a suitable computing environment in which the computing device 21, the system controller 23, and the controller 26, respectively, can be implemented. The computing device 21, the system controller 23, and the controller 26 can be implemented, at least in part, in the general context of computer-executable instructions, such as program modules, being executed by the computer 31. Generally, program modules include routine programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Those skilled in the art can implement the following description and / or block diagrams in computer-executable instructions storable on a computer-readable medium. Moreover, those skilled in the art will appreciate that the invention can be practiced with other computer system configurations, including multiprocessor systems, networked personal computers, minicomputers, mainframe computers, etc. Aspects of the invention can also be practiced in distributed computing environments where tasks are performed by remote processing devices linked through a communications network. In a distributed computing environment, program modules can be located in both local and remote memory storage devices.

[0022] The computer 31 shown in FIG. 3 comprises a conventional computer having a central processing unit (CPU) 27, memory 33, and a system bus 35. The system bus 35 couples various system components, including the memory 33, to the CPU 27. The system bus 35 can be any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. The memory 33 includes read-only memory (ROM) and random access memory (RAM). The central processing unit or processor 27 is coupled to memory configured to store values ​​indicative of sensor output signals and to store instructions configured to process the stored values ​​to generate output signals related to the acoustic fields of the test specimen and virtual components coupled to the test specimen. A basic input / output system (BIOS), containing basic routines that help transfer information between elements within the computer 31, such as during start-up, is stored in the ROM. A storage device 37, such as a hard disk, floppy disk drive, or optical disk drive, is coupled to the system bus 35 and is used for storing programs and data. It will be understood by those skilled in the art that other types of computer-readable media accessible by a computer may also be used as storage devices, such as magnetic cassettes, flash memory cards, digital video disks, random access memory, read-only memory, etc. Typically, programs are loaded into memory 33 from at least one of storage devices 37, with or without accompanying data.

[0023] Input devices such as a keyboard 41 and a pointing device (mouse) 43 allow a user to provide commands to the computer 31. A monitor 45 or other type of output device is further connected to the system bus 35 via an appropriate interface to provide feedback to the user. If the monitor 45 is a touch screen, the pointing device 43 may be integrated with the monitor 45. The monitor 45 and input pointing device 43, typically a mouse, together with a corresponding software driver, form a graphical user interface (GUI) 47 for the computer 31, which is particularly useful for the embodiments described below.

[0024] An interface 49 in each of the computing device 9 and the system controller 23 enables communication between the computing device 9 and the system controller 23. Similarly, an interface 49 in each of the system controller 23 and the controller 26 enables communication between the system controller 23 and the controller 26. In addition to transmitting signals 19 or receiving signals 15 as described above, the interface 49 also represents circuitry used to transmit or receive other parameters of the physical system, such as the status of locks, doors, indicators, whether power is applied, etc. Typically, such circuitry includes digital-to-analog (D / A) converters and analog-to-digital (A / D) converters as are well known in the art. The controller 26 can also include an analog controller with or without digital supervision, as is well known. The functions of the computing device 21, the system controller 23, and the controller 26 can be combined into a single computer system. In another computing environment, the controller 26 is a single-board computer operable on the network bus of another computer. This other computer can be the controller 23 or another supervisory computer. The schematic diagram of FIG. 3 is intended to generally represent a computer for these and other suitable computing environments.

[0025] 4 is a block diagram illustrating the processing of sensor signal(s) 48A, 48B from a testing machine 10 applying a load or displacement to a test specimen 13 to render audible and / or inaudible acoustic fields and information related to vibrations generated by the test specimen 13 and virtual components (not shown) coupled to the test specimen 13. Typically, a sensor, such as a load cell 24 or an accelerometer 18 shown herein as an example (although, as noted above, other forms of sensors, such as velocity, displacement, etc., can also be used), provides a sensor output signal indicative of a force 48A or a movement 48B. As shown, the sensed force 48A can be used as a process signal. Alternatively, if movement 48B is provided, as sensed by the accelerometer 18, the movement 48B can be processed directly or converted to a corresponding force via an acceleration-to-force conversion module 50, which uses, for example, a model based on an equation between force and acceleration or an empirical lookup table. Since the higher frequency components are generally most desirable, a suitable high pass filter 52 can be used to remove any undesired low frequency components from signals 48A and / or 48B.

[0026] The signal(s) 48A, 48B from the sensors are provided to a signal conversion processing circuit or module 54 configured to provide an output signal 56 related to the audible and / or inaudible acoustic ranges of the test specimen and virtual components coupled to the test specimen but not present in the testing machine 10. For example, in a damper used in a vehicle, a flexible component present near the upper shock mount can act like an acoustic speaker driven by a damper rod forcing function. One aspect of the present invention is to address the mechanical impedance mismatch between the test specimen 13 and its virtual components, such as the upper shock mount and surrounding flexible members, and directly convert these vibrations into the resulting acoustic noise (sound pressure) expected in a real vehicle body. Although the mechanical vibration response of the upper shock mount and surrounding structure can be very complex in its mechanical impedance characteristics, these coupled components, which can significantly contribute to the generated acoustic noise, can be modeled using current techniques in FEA (Finite Element Analysis), as shown at 58. In one embodiment, the impedance can be modeled and characterized using, for example, signal transformation processing circuitry or module 54, which generates convolved information embodied, for example, as a frequency response function. This can be done using FEA harmonic response analysis 60 of FEA model 58, which can then be represented by a reduced order state space model between finite input locations and finite output locations used by signal transformation processing circuitry or module 54.

[0027] Two exemplary methods are presented for converting the response of the test specimen 13 (e.g., damper rod response or a physical damper rod with a physical elastomeric upper shock mount included in the physical specimen setup) into the resulting noise emission from a virtual speaker (a coupled virtual component). One uses the force measured on the test specimen 13 (e.g., the damper rod or a physical damper rod with a physical elastomeric upper shock mount included in the physical specimen setup) as the input stimulus to the virtual component. The other uses the measured damper rod acceleration or a physical damper rod with a physical elastomeric upper shock mount included in the physical specimen setup as the input stimulus to the virtual component. The first case (force input) may be more direct and straightforward. In the case of a damper, although it may exist with the rest of the specimen, the upper shock mount region typically includes an elastic isolator attached to the metal body structure (this elastomeric isolator can be represented as part of the virtual representation or included as part of the physical specimen). Through FEA analysis, the mechanical motion of this upper mount region resulting from the input forcing function can be generated through harmonic modal analysis.

[0028] As far as inputs to the FEA model are concerned, force stimuli are generally introduced at actuator locations in the FEA model. Output displacements, accelerations, and forces are then measured at various locations to help determine transmissibility. Often, the dynamic stiffness of a "standard" or actual specimen is measured. Sometimes, acceleration compensation may be required. This can all be modeled using harmonic FEA analysis. Typically, harmonic analysis is used to predict the response to different discrete sinusoidal input stimuli, but this frequency-by-frequency response can be used more generally to study the system's response to any input, sinusoidal or non-sinusoidal. This sinusoidal discrete frequency data is the information needed to create a frequency-domain transfer function, or alternatively, perhaps some other form of transformation as shown herein.

[0029] This harmonic modal analysis can generate a frequency response function of the motion (displacement or acceleration) output to the force input. This frequency response function can be approximated using fitting techniques to a low-dimensional continuous transfer function of reasonable size for the frequencies of interest. This continuous transfer function can be converted to an equivalent discrete transfer function and then implemented as a digital filter that can be applied to the signal in real time, i.e., as the test specimen is actuated by the actuator 22. This digital filter then represents the forced response (dynamic response) of the virtual component acting as a virtual speaker.

[0030] The measured forces 48B from the high-bandwidth force transducers 24 in the physical load frame 11 can be transmitted to this model of the virtual loudspeaker in a signal conversion processing circuit or module 54 (through convolution with a digital filter), and the resulting output signal 56 can then be transmitted to a physical speaker 64, if desired, so that a human hears the simulated noise emanating from the vehicle body in real time. Preferably, the physical speaker 64 should have high fidelity so as not to introduce its own dynamics into the simulation. This provides a real-time subjective assessment of the acoustic behavior of the physical test specimen 13 in the load frame 11 coupled with any selection of virtual components, such as an upper shock mount assembly from any particular vehicle platform, used in the FEA model 58. Thus, the test machine 10 with the signal processing described herein can assist in identifying which particular load or displacement profiles, such as from a road, generate unwanted noise, as well as identifying the underlying source of the noise from within the physical and / or virtual components of the test specimen.

[0031] In the case of a damper, for example, the impedance of the upper shock mount and the body structure can significantly affect the presence or absence of acoustic noise, i.e., "chuckle" noise. For example, a physical test specimen, i.e., a damper or a damper and upper mount, cannot determine the presence of chuckle noise by itself. Only a test specimen, such as the coupled system, i.e., the impedance of the damper and upper shock mount and body structure, virtually modeled herein, can accurately reproduce the chuckle. Thus, using this approach using virtual representations, different upper coupling assemblies and / or virtual coupling components with different physical or material properties can be very quickly evaluated using real test specimens, such as the damper described by way of example.

[0032] It should be noted that the forces transmitted through the test specimen 13, e.g., the damper rod, may be affected to some extent by coupling with the (virtual or physical) upper shock mount and the surrounding (virtual) body structure. Note that some portions of the body structure may also be included in the physical test specimen if practically feasible. Much of the coupling behavior depends on the most elastic member in the coupled system, typically an elastomeric component. For some test specimens, such as dampers, the majority of the acoustic signature is expected to come from the surrounding virtual metallic, coupled flexible member. Therefore, it may be advantageous for the actual elastomeric component in the test specimen, or the virtual elastomeric component if modeled, to match relatively closely the modeled actual elastic dynamic stiffness components present in the system. Meanwhile, a virtual component acting as a speaker will still reproduce noise even if the dynamic stiffness is off by, say, a factor of two.

[0033] Alternatively or in addition to transmitting the resulting output signal 56 from the signal conversion processing circuit or module 54 to a speaker 64, the output signal 56 can be provided to a sound processing module 62 to calculate the resulting pressure fluctuations (and therefore sound pressure levels) related to the output signal 56. This estimated sound pressure level can then be used as a more objective test for acceptable noise emissions, and the resulting data from this test can be rendered to the user in any convenient data format on a hard copy or computer-readable medium, such as a spreadsheet or table, and / or rendered to the user on a suitable monitor. For example, these estimated sound pressure levels can be filtered using conventional weighting and converted to 1 / 3 octave bands. Optionally, the user can configure pass / fail criteria that can be used, for example, by assigning an overall dBA acceptable level or acceptable dBA levels for one or more selected octave bands, which can be processed by the sound processing module 62 and then rendered to the user. This description shows 1 / 3 octave bands as examples since these are most often used by audio engineers, but time domain traces or power spectra or other frequency domain representations can also be used.

[0034] It should be noted that in yet another method of converting measured acceleration into acoustic noise, the inverse forced response of the test specimen is used in the simulation chain. In this method, the measured acceleration is first filtered by the signal conversion processing module 54 as a digital filter representing the inverse forced response, and then multiplied by the force response of a virtual speaker. The resulting signal is then sent to a physical speaker 64 for playback or provided to the sound processing module 62.

[0035] At this point, it should be noted that embodiments of the present invention are not limited to real-time processing, i.e., generating output signal 56 substantially in real time in response to the load and / or displacement of test specimen 13 provided by signals 48A and / or 48B. In other words, processing by signal conversion processing circuitry or module 54 may not be performed in real time, but rather may be performed based on stored data indicative of signals 48A and / or 48B after the force and displacement on test specimen 13 has been completed, for example. Similarly, signal conversion processing circuitry or module 54 need not process data to generate output signal 56 that may produce acoustic noise in a manner perceptible by humans, but rather may process data to generate additional information that is not necessarily perceptible to humans.

[0036] Finally, the concepts presented herein should not be limited to FEA modeling and subsequent harmonic analysis. In particular, modeling and analysis can take other forms, such as, but not limited to, transfer path analysis. The transfer path analysis can be based on virtually modeled components or on measurements obtained experimentally from the actual components, with this measurement data being used to assist in the creation of the virtually modeled system or to obtain convolution information or relationships, such as FRFs (Frequency Response Functions), used by signal conversion processing circuitry or module 54 or, as the case may be, some other transformation. In FIG. 4 , processing module 60 can include transfer path analysis of the FEA model. Alternatively, actual test specimens and coupled components, here, vehicle components as examples, are used at 70 and are instrumented for testing to obtain vibration measurements. If desired, a vibrator or the like can be attached to the actual components and activated to obtain vibration measurements, typically forces and / or accelerations, or such measurements can be obtained from actual field data of the test specimens and coupled components. The vibration measurements are then experimentally analyzed at 72 to obtain a transfer function (or some other transformation) that is used in the signal conversion processing circuit or module 54. Transfer path analysis is well known and is described in the 2018 Siemens Product Lifecycle Management Software Inc. white paper, "Transfer Path Analysis," which is incorporated herein by reference.

[0037] Although the subject matter has been described in terms of specific environments, structural features, and / or methodological acts, it should be understood that the subject matter defined in the appended claims is not limited to the above-described environments, specific features, or acts, as determined by a court. Rather, the above-described environments, specific features, and acts are disclosed as example forms of implementing the claims.

Claims

1. 1. A system for use with a testing machine having an actuator for applying a load or displacement to a test specimen, comprising: a sensor operably coupled to the test specimen to sense motion or force and provide a sensor output signal; a signal conversion processing circuit coupled to receive the sensor output signal and configured to provide an output signal related to the audible and / or inaudible acoustic ranges of the test specimen and a virtual component coupled to the test specimen; an output device coupled to receive the output signals related to the audible sound field and / or the inaudible sound field and to render information related to vibrations generated by the test piece and the virtual component coupled to the test piece; A system comprising:

2. The system of claim 1 , wherein the output device comprises a speaker.

3. The system of claim 1 , wherein the output device comprises a module for visually rendering the output signal.

4. The system of claim 3 , wherein the output device comprises a speaker.

5. The system of claim 1 , wherein the signal conversion and processing circuitry comprises analog circuitry.

6. 2. The system of claim 1, wherein the signal conversion processing circuitry comprises a processor coupled to a memory configured to store values ​​indicative of the sensor output signal and to store instructions configured to process the stored values ​​to generate the output signal related to the acoustic field of a test specimen and a virtual component coupled to the test specimen.

7. The system of claim 6 , wherein the processor and the instructions include a digital filter.

8. The system of claim 7 , wherein the output signal is generated substantially in real time with the sensor output signal.

9. The system of claim 6 , wherein the output signal is generated non-real-time based upon receipt of the sensor output signal.

10. 1. A method for generating audible and inaudible information in an acoustic field related to a test piece and a virtual component coupled to the test piece, comprising: obtaining a signal transduction processing relationship of a test specimen and a component coupled to the test specimen, the signal transduction processing relationship relating the motion or force of the test specimen to audible and / or inaudible vibrations generated by the test specimen and a virtual component coupled to the test specimen due to the motion of the test specimen and / or the force applied to the test specimen; mounting the test specimen in a testing machine having an actuator configured to move and / or apply a force to the test specimen; sensing at least one of movement of the test specimen and / or force applied to the test specimen to obtain a sensor output signal; applying the sensor output signal to the signal conversion processing relationship of the test strip and a component coupled to the test strip; obtaining output signals from the signal transformation processing related signals related to the acoustic region of a test specimen and a virtual component coupled to the test specimen; applying the output signal to an output device to render information related to the audible and / or inaudible vibrations generated by the test specimen and the virtual component coupled to the test specimen; and A method comprising:

11. The obtaining of the signal conversion processing relationship includes: obtaining a finite element analysis model of the test specimen and the component coupled to the test specimen; performing harmonic analysis on the finite element analysis model to obtain the signal transformation processing relationship; The method of claim 10, comprising:

12. The obtaining of the signal conversion processing relationship includes: obtaining a finite element analysis model of the test specimen and the component coupled to the test specimen; performing a virtual transfer path analysis on the finite element analysis model to obtain the signal transformation processing relationship; The method of claim 10, comprising:

13. The obtaining of the signal conversion processing relationship includes: constructing the test specimen and the component coupled to the test specimen; moving and / or applying a force to the test specimen; measuring vibrations in the test specimen and / or the component coupled to the test specimen; performing a transfer path analysis using the measured vibration to obtain the signal transformation processing relationship; The method of claim 10, comprising:

14. A base and At least one pair of posts joined to the base; a crosshead joined to the strut at a location spaced from the base; at least one pair of test strip holders, a first test strip holder supported by the crosshead and facing the base, and a second test strip holder supported by the base, the base being the portion coupled to each of the struts closest to the crosshead; an actuator connected in series between one of the test specimen holders and the corresponding base or crosshead; a sensor operably coupled to the test specimen to sense motion or force and provide a sensor output signal; a signal conversion processing circuit coupled to receive the sensor output signal and configured to provide an output signal related to the audible and / or inaudible acoustic ranges of the test specimen and a virtual component coupled to the test specimen; an output device coupled to receive the output signals related to the audible sound field and / or the inaudible sound field and to render information related to vibrations generated by the test piece and the virtual component coupled to the test piece; A test system comprising:

15. The system of claim 14 , wherein the output device comprises a speaker.

16. The system of claim 14 , wherein the output device comprises a module for visually rendering the output signal.

17. The system of claim 16 , wherein the output device comprises a speaker.

18. 15. The system of claim 14, wherein the signal conversion and processing circuitry comprises analog circuitry.

19. 15. The system of claim 14, wherein the signal conversion processing circuitry comprises a processor coupled to a memory configured to store values ​​indicative of the sensor output signal and to store instructions configured to process the stored values ​​to generate the output signal related to the acoustic field of a test specimen and a virtual component coupled to the test specimen.

20. 20. The system of claim 19, wherein the output signal is generated substantially in real time with the sensor output signal.

Images