The Piezoshaker excitation systems are designed for vibration measurement and non-destructive testing and consist of a Piezoshaker, a Piezoamplifier, and a function generator. Optionally, the waves of the Piezoshaker, transmitted to the test object, can be monitored by isi-sys Shearography / ESPI systems. Our Shearography / ESPI systems enable us to monitor full field vibration such as e. g. natural object vibrations. Another application of the Piezoshaker-System is for excitation with acoustic and ultrasonic waves in the field of material processing and manufacturing technology. The Piezoshaker-System Setup is shown in the figure on the left.
The video on the right shows the lamb waves, generated by the Piezoshaker that is attached at the bottom of the specimen. The waves travel across the object’s surface and excite the five local subsurface defects on the top. The local defects vibrate differently, depending on their local mechanical properties (stiffness). Only very little power of the Piezoshaker is required, when the excitation frequency is close to the local defect resonance frequency. This principle is used in non-destructive testing, for example, especially to locate delaminations in sandwich structures. Here, usually, the Piezoshakers of the PS‑X series with vacuum adapter are used.
Piezoshaker:
NEW PS-W-02 for continuous operation in automated production lines
The PS W 02 Series is perfectly suitable for continuous operation due to its innovative cooling system with forced convection by compressed air. The Piezoshaker is intended to be mounted to a pneumatic cylinder, which is used to press the contact pin to the measuring object’s surface. This method allows the contact pressure to be controlled by the user. The contact pin is exchangeable and can be adapted to customer requirements. Due to its small contact area, it can be placed on small surfaces. With the PS-W-02 Series, dynamic excitation is possible in both stationary and moving modes, allowing material excitation in continuous manufacturing processes. This Piezoshaker-Series features an internal temperature sensor.
Applications: Dynamic Excitation for Welding Processes
NEW PS-X-04 for High Dynamic Operation
The PS-X-04 Series is designed lightweight and compact for mounting on the test object surface by vacuum. Using the sliding valve, the Piezoshaker can easily be attached or removed from the material surface. It contains an axial movable Suction Cup Adapter (Sealing), which allows the Piezoshaker to be easily attached to concave or convex surfaces with level differences up to 6mm. The PS-X-04 supports dynamic vibration excitation in a frequency range up to 100 kHz. Different pneumatic connecting elements are available.
PS-X-03 Series with Suction Cup adapter
The PS-X-03-Series is designed for non-destructive testing purposes in combination with ESPI/Shearography. It is fixed on the object’s surface by vacuum via a suction cup. The pressing force is adjustable by the vacuum level. Different actuator types are available for different frequency ranges and forces in combination with different counterweight mass.
Applications:
Dynamic loading on a large yacht hull
Dynamic loading on a wind turbine blade and resin bridges
Dynamic excitation on a spacecraft
Dynamic loading on a yacht mast
Dynamic loading on rudder blade
PS-AC‑X Series with active cooling
The Piezoshaker PS-AC‑X series is used for broadband vibration excitation, mainly in applications for non-destructive testing in combination with Shearography and Thermography systems. It is very compact and rigid as well as for quick set-up and easy handling. The design is based on the established Piezoshaker type PS-X-03, but in contrast to PS-X-03, our new series uses compressed air for active cooling as well as for generation of the vacuum for the suction cup. The active cooling allows longer continuous operation at higher power compared to the PS-X-03 versions or a longer lifetime at higher power output.
Use as suction-foot for tripod: Compared to the PS‑X series, the increased sealing diameter generates higher forces, which allows the usage of the standard suction-foots for the isi-sys suction tripods. For example, two PS-AC‑X can be placed left and right next to the field of view and therefore close to the area of interest.
Applications: A mobile nondestructive testing (NDT) system for fast detection of impact damage in fiber-reinforced plastics (FRP)
PS-L-02-Series with mounting table and forced cooling
The PS-L-02 Series is designed for vibrating small objects such as electronic devices at high frequencies. The adapter table is exchangeable and can be customized with threads for object mounting (M4). Mounting of load cell for force measurement is optional. The center of Mass of the object should be near the center. For continuous operation at high loads and frequencies forced air cooling is required. For this purpose, a DC centrifugal fan, which can be connected to the amplifier, is included in the package. It is available with different characteristics (frequency range, amplitudes, and forces).
PS-M-LC-Series with screw mount and load cell adapter
The PS-M-LC-Series is designed for screwing or gluing on the object surface and can be combined with load cells. The Piezoshaker is available with actuator types for different force and frequency ranges in combination with variation of the housing diameters defending the counterweight mass of the shaker body. A suitable and common load cell is for example the PCB model No. 201B02 (Force Sensor ICP® quartz force ring), in which the maximum Frequency is 90kHz.
Piezoamplifier
NEW HPDA‑0–180 for High Dynamics Operation of Piezo Actuators
The HPDA‑0–180-1C Piezoamplifier is specially designed to drive isi-sys Piezoshakers for a variety of applications where high power in combination with low weight and compact size is a great advantage for mobility and flexible handling, e.g. for mobile NDT applications. This supports highly dynamic excitation due to its wide bandwidth with frequencies up to 100 kHz. Large forces and acceleration have been generated in combination with the different isi-sys Piezoshaker modules. The output power can be inspected by the monitoring system. The HPDA‑0–180 has overtemperature protection for the Piezoshaker series with a temperature sensor. Different Versions with multiple channels are available.
Excitation power, force, and acceleration of a Piezoshaker system are functions of the frequency, and its amplitude and thus also depend on the amplifier output, characterized by its transfer function. You can request the transfer function of the amplifier from isi-sys. The frequency range for application of the Piezoshaker is limited depending on its electrical capacity. Adjustment of the excitation power is usually possible via the amplitude and frequency generated by the function generator and can be monitored via the voltage and current monitor outputs.
Function generator / DAQ unit
Different function generators are supported by the Software isi-Studio. It offers to run the required features for non-destructive testing such as automatic frequency sweeping. The standard function generator / DAQ unit also offers to measure the current and voltage output of the amplifier. This permits monitoring of the power applied to the surface.
Vacuum sources
The Piezoshaker can be attached by vacuum to the object’s surface. When pressurized air is not available, isi-sys offers small vacuum pump units. Two independent vacuum sources are recommended when also a tripod with suction cups is used. The vacuum level is adjustable via pump speed, which is recommended to prevent damage to the object’s surface by vacuum forces.
Application examples of the Piezoshaker system:
Dynamic Excitation for Welding Processes
Dynamic loading on a large yacht hull
Dynamic loading on a wind turbine blade and resin bridges
Dynamic excitation on a spacecraft
Dynamic loading on a yacht mast
Dynamic loading on rudder blade
Should you need more detailed information or have special questions, please contact us per email — info@isi-sys.com.
