Title | Description |
Velocity vs acceleration
|
An acceleration signal is compared with a velocity signal by measuring the
velocity of an accelerometer that is driven by a chirp.
|
PU versus
PP measurements
|
A PU and a PP measurement are compared. The mathematics is shown in small
steps.
|
Velocity vs intensity visualisation of a thin plate
|
For an experiment the differences between surface velocity and sound
intensity visualisation in a 33x43cm, 0.8mm thin plate are measured.
|
Scan and
listen method: vibration measurement
| For a lab experiment
the modes in a 33x43cm 0.8mm thin plate are found with a simple scan and
listen method. The method employs one PU-mini probe. The normal velocity of
the surface is scanned and the signal is amplified and made audible trough
headphones.
|
|
| |
| Leaflet Acoustic Camera | Leaflet about the acoustic camera.
|
| SI camera ATG |
ATG has developed software which can visualize real-time
sound intensity, with the use of a Microflown PU-mini array.
|
Microflown Based non Contact Measurements of Structural Velocity in the Very Near Fields (pdf)
| Microflown
acoustical particle velocity sensors are a viable alternative to both
laser vibrometers and mini-accelerometers, enabling truly new testing
opportunities whilst reducing often the overall system costs!
Close
to an object (in the so called very near field), and without the need
for advanced software, (an array of) Microflown acoustical particle
velocity sensors can be used for the non contact measurement of the
normal component of the structural velocity. For instance non contact
multi channel measurements on (in) stationary sources become feasible,
as well as capability of measuring airborne sound.
Due to the
miniaturized size and working principle of the Microflown, measurements
in confined spaces are possible now, at elevated temperatures up to 200
degrees Celsius and above and in situations with high levels of
background noise.
|
Particle Velocity Based P-U Sound Probes for Car Panel Noise Analysis (pdf)
| The
use of particle velocity based fully integrated p-u sound probes allows
the development of new sound power based measurement methods to
optimize the acoustical packages for car interiors. |
P-U Based in situ Characterization of Damping Materials (pdf)
| A
new universal tool to the acoustical world has become available to
characterise acoustical properties of materials under all sorts of real
world conditions. Uniformity, ease of use and productivity of
measurements are increased dramatically. Costs of infrastructure and
samples are reduced significantly.
Includes paper presented at the ISMA 2004 in Leuven, Belgium. |
Very Near Field Structural Dynamics (pdf)
| In
acoustics concepts like the ‘far field’ and ‘near field’ are well
known. The sound field at a position much closer to the source than the
size of the source itself, is introduced as the ‘very near field’ It
will be shown that in the very near field the particle velocity is
frequency independent and almost independent of place whereas the sound
pressure is almost independent of place but suppressed and frequency
dependent. |
In situ Impedance Measurements (pdf)
| Measuring
method of sound reflection and absorption characteristics based on the
particle velocity and its applications to measurements on such as
drainage pavement of road surface. |
Near Field and Very Near Field Source Localization (pdf)
| The
availability of dedicated Microflown particle velocity sensors offers
entirely new ways for solving numerical inverse methods for near field
source localization. Furthermore, in the proximity of an object, e.g.
in the so called very near field, uncomplicated direct measurements
methods without computational power are available now. |
In situ Impedance Measurements (pdf)
| The
availability of the p-u sound probe offers, amongst others, new
techniques to measure impedance of various materials in situ. The
traditional method of measuring samples in a calibration tube under
laboratory conditions is no longer required! |
Structural Vibration Measurements (pdf)
| Microflown
Scanning Probes offer the opportunity to measure 3D on a vibrating
surface, either by using a three dimensional probe or by repositioning
the single element Scanning Probe. |
Far Field Source Localization (pdf)
| The
combination of dedicated particle velocity sensors, a sound pressure
microphone and some advanced measuring techniques offers new
possibilities to localize sound sources in the far field. |
Representation of 3D Sound Fields on Loudspeakers (pdf)
| Until
recently, sound field and sound intensity measurements were scarcely
used, mainly due to various practical and technical limitations. Here a
representation method is given for the sound field of loudspeakers. |
Three Dimensional Impulse Response (pdf)
| The
3DP is a measurement system developed at Meyer Sound for architectural
acoustic measurements. It consists of one pressure microphone, three
Microflown velocity probes, and custom Meyer Sound hardware and
software. |
Low DC flow Measurement with a High Spatial Resolution (pdf)
| A
Scanning Microflown Probe is used to measure a spatial DC flow field
that was generated by a high number of (250µm in diameter) little holes
in line. The maximal air-velocity from the holes was in the order of
1mm/s. |
R&D 
