Publications
Categories
Testing of amplified piezoelectric actuator in a combined vibration and acceleration
19 June 2023
Sandia National Laboratories has previously tested a capability to impose a 7.5 g-rms (30 g peak) radial vibration load up to 2 kHz on a 25 lb object with superimposed 50 g acceleration at its centrifuge facility. This was accomplished by attaching a 3,000 lb Unholtz-Dickie mechanical shaker at the end of the centrifuge arm to create a “Vibrafuge”. However, the combination of non-radial vibration directions, and linear accelerations higher than 50g’s are currently not possible because of the load capabilities of the shaker and the stresses on the internal shaker components due to the combined centrifuge acceleration.
The design and qualification of the piezo actuated
19 June 2023
As part of the Lisa Technology Package (LTP) on board the LISA-PATHFINDER spacecraft, the LISAPATHFINDER interferometer is of the heterodyne Mach-Zehnder type. It requires as input two light beams derived from the same source but with a small frequency difference (a few kHz). These two optical beams are produced in the Laser Assembly (LA) via the “Laser Modulation Unit” (LMU). The LMU includes an optical bench, two Acousto-Optic Modulators and two Optical Delay Lines [1].
Thermal vacuum behaviour of a stepping piezo actuator
19 June 2023
The presented work illustrates the design of a new high force Stepping Piezoelectric Actuator (SPA) and describes its Thermal Vacuum testing as performed by ESTL, in order to investigate SPA compatibility with vacuum environment within a wide temperatures range; from +60°C down to -180°C. A dedicated test bench was designed, in order to check motor force and speed for all performed tests. Instrumentation, testing and observations about tribological behaviour of friction interface have been realized by ESTL, showing interesting perspectives.
Tool adaptor for active vibration control in turning operations
19 June 2023
A tool adaptor with built-in active vibration damping device to dynamically stabilize the turning process is presented in this paper. It can be used in standard CNC-lathes and allows the usage of off-the-shelf tool heads. The vibration compensation system is based on a multilayer piezoactuator that is in collocation with a piezoelectric force sensor. An analogue controller based on the integral force feedback method is used for active damping.
Tubular ultrasonic transducer: MUST with axial excitation versus conventional with radial excitation
19 June 2023
This paper presents comparison between two excitation solutions for tubular ultrasonic transducer. The axial excitation is widespread in conventional ultrasonic transducer. The radial excitation is proposed in order to have an uniform acoustic energy all along the tube. This excitation approach is also proposed to allow the modularity by adding several tubes.
Ultrasonic Piezo Drive UPD for direct drive motorization
19 June 2023
Existing piezo motors such as travelling wave motors present several technical limitations, they are not useable for linear drive, they cannot be easily adapted to specific rotational needs and the development of customised solution is expensive. The proposed Ultrasonic Piezo Drive (UPD) aims at overcoming these limitations. It is a shell-based stator using multilayered piezoceramics in d33 mode. Excited at only 1-10V, it produces an ultrasonic elliptical vibration large enough to direct drive any type of second body by friction. Tangential driving properties of UPD20 are typically in the range of 100-200mm/s max speed and 15-30N max force.
