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Design and tests of a demonstrator for filet compensation mechanism
5 January 2016
Future matrix sensors will acquire an area on ground and are then susceptible to image shift due to satellite movement during acquisition. Design, Build and Test a breadboard mechanism that could shift telescope line of sight and freeze observed area during image acquisition.
FSPA and BSMA Nanometric positioning actuators for ground and space applications
19 June 2023
Many applications and more specifically space projects show need for a stable sub-micrometre positioning actuator. In order to meet this need, Cedrat Technologies has designed the new FSPA brand. This linear stepping actuator offers sub-micrometric positioning resolution along 5mm stroke combined with high actuation force (>100N) and the ability to hold its position without power.
The IASI-NG instrument is one of the key payload on-board METOP-SG which is a new meteorological satellite for Europe. The instrument is based on a Mertz interferometer and requires a very precise positioning of an optical blade used to separate the interferometer’s branches. A dedicated version of the FSPA, the Beam Splitter Mechanisms Actuator (BSMA) is then developed to achieve this nanometric positioning which is a key parameter for the overall instrument performance.
This paper firsts present the internals of both FSPA and BSMA actuators. Major design differences and their respective impact on the resulting performances are detailed. Results from the acceptance and qualification test campaigns are also presented.
Design of a dynamic tribometer applied to piezo inertia drive motors
7 November 2019
In Inertia Drive Motors, generated motion is based on stick-slip principle. Current analytical models are predictive enough to calculate qualitatively their optimal performances, such as maximal step size and speed, with relatively few input parameters. Butn they do not take into account the contact life and temporal evolution of parameters as friction factor all along lifetime of IDM. So analytical models reach their limitswhen precise predictions are necessary.
Design of a dynamic tribometer applied to piezoelectric Inertia Drive Motors – In situ exploration of stick-slip principle
19 June 2023
In Inertia Drive Motors, generated motion is based on stick-slip principle. Current analytical models are predictive enough to calculate qualitatively their optimal performances, such as maximal step size and speed, with relatively few input parameters. But, they do not take into account the contact life and temporal evolution of parameters as friction factor all along lifetime of IDM. So, analytical models reach their limits when precise predictions are necessary. This investigation aims at understand wear mechanisms to model temporal evolution of friction. Such an understanding requires the reconstitution of the contact life through the evaluation of 1st and 3rd body flows. To do so, a new IDM-representative tribometer is designed. First bodies – coated TA6V and polymer – are not see-through. They are replaced alternatively by an intermediate transparent first body to observe the contact dynamically and in-situ. Friction factor, step size and mean speed are also measured. Preliminary results shows that wear profiles from real IDM and tribometer are similar. Direct observations bring out particles of TA6V coating are firstly snatched, then moves in contact and finally trigs others particle detachments.
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.
Development of magnetic fast steering mirror prototype for optical pointing applications
7 June 2018
Fast Steering Mirrors are core products continuously developed by Cedrat Technologies (CTEC) for optical pointing applications, for Space, and Optronic domains. During the last decade, main development efforts where focused on piezoelectric mechanisms technology, in order to achieve ultra-high frequency bandwidth control performance over small angle strokes. New applications under maturation in Europe, such as laser optical communication, require much higher angle strokes compared to the existing state of the art, which cannot be easily achieved by piezoelectric technology. Therefore CTEC is focusing on the development of a new Fast Steering Mirror family based on high angle stroke magnetic actuators. This paper presents this new steering mechanism concept, and the prototype performance results expected.
