Publications
Categories
Contactless Position sensors for space mechanisms based on eddy current sensing
19 June 2023
For more than 20 years, CTEC has been involved in various space missions, delivering products designed for severe environment conditions (vibrations, shocks, vacuum, humidity, wide thermal range including cryogenic). Eddy current sensor (ECS) technology, using printed circuit board (PCB) for printed coils, provides both a good resolution/accuracy and a good robustness against temperature variations.These sensors are available commercially off the shelf (COTS).
Amélioration des performances des actionneurs APA®
19 June 2023
Increase the dynamic mass energy density and reduce the effects of inertia by playing on materials and geometry.
Amplified Piezoelectric Actuators:Static & Dynamic Applications
19 June 2023
Piezo actuators can be classified in three main categories: stack-type actuators, external/internal leveraged actuators and frequency-leveraged actuators (such as stepping motors and ultrasonic motors) [1]. Although Cedrat Technologies has developed several solutions using multilayered piezo ceramics and shell-based structures [2, 3], Amplified Piezo Actuators have today received the largest market interest.
An improved accurate Beam Steering piezoelectric Mechanism for ATlid instrument
19 June 2023
A new tip tilt mechanism based on low voltage piezoelectric actuators has been designed by Cedrat Technologies to answer the high level of stability required for the Earthcare satellite. The Beam Steering Assembly aims to deviate a pulsed high energy UV laser beam to compensate for misalignment between the emission and reception paths of ATLID [1] with a very high stability and resolution. In this paper, the authors points out the BSM development with the main mechanism design issues including performances, mechanical and thermal stability; low power consumption; high integration level; high reliability and safety; cleanliness requirements and give the results of the qualification campaign done at Cedrat Technologies’ to establish the final functional performances in preparation of the Flight Models deliveries for the BSM.
Analysis of Needle–Tissue Friction during Vibration-Assisted Needle Insertion
19 June 2023
In this paper, a vibration-assisted needle insertion technique has been proposed in order to reduce needle–tissue friction. The LuGre friction model was employed as a basis for the current study and the model was extended and analyzed to include the impact of high-frequency vibration on translational friction. Experiments were conducted to evaluate the role of insertion speed as well as vibration frequency on frictional effects. In the experiments conducted, an 18 GA brachytherapy needle was vibrated and inserted into an ex-vivo soft tissue sample using a pair of amplified piezoelectric actuators. Analysis demonstrates that the translational friction can be reduced by introducing a vibratory low-amplitude motion onto a regular insertion profile, which is usually performed at a constant rate.
ATLID Beam Steering Mechanism and derived new piezoelectric based devices for optical applications
19 June 2023
In Space & Defence (as well as in many others fields), there is a trend for miniaturisation in active optics requiring new actuators. Applications also often require the ability to withstand high vibrations and shocks levels, as well as vacuum
compatibility for space applications. A new generation of small and smart actuators such as piezoelectric (piezo) actuators, are resolving this trend, thanks to their capacity to offer high energy density and to support both extreme and various requirements. This paper first presents the BSM mechanism and its requirements, the technologies involved in
the design and the validation campaign results. Secondly, a derived XY piezoelectric positioning stage based on the same APA® and associated Strain Gage sensing technology is presented with its associated performances. Finally, a new piezoelectric motor based on the APA® technology, which allows the combination of long stroke while maintaining high
resolution positioning of optical elements, is presented with experimental performances.
