Mechanisms
Categories
Rosetta Midas successful launching
19 June 2023
Successful commissioning of the first flight application for C. T. in ESA / ROSETTA mission. The ROSETTA satellite has been successfully launched the 2nd of March 2004 from Kourou, French Guyana, using an Ariane-5 G+ launcher. The rendezvous with the new targeted comet “Churyumov – Gerasimenko” is expected in November 2014.
A bistable piezoelectric harvester for wideband mechanical frequency excitation
19 June 2023
The developments of autonomous systems such as for self health monitoring, embedded systems are increasingly used in industrial applications. The energy supply is a key point for the development of such systems. Solutions based on battery have limited life time and the power supplies through wires aren’t always appropriate and easy to install. Furthermore, the battery recycling is complex and an expensive process. The researches on power supply through harvesting systems are increasing in the same way the autonomous systems.
Cardiolock: an Active Cardiac Stabilizer
19 June 2023
Off-pump Coronary Artery Bypass Grafting (CABG) is still today a technically difficult procedure. In fact, the mechanical stabilizers used to locally suppress the heart excursion have been demonstrated to exhibit significant residual motion. We therefore propose a novel active stabilizer which is able to compensate for this residual motion. The interaction between the heart and a mechanical stabilizer is first assessed in vivo on an animal model. Then, the principle of active stabilization, based on the high speed vision-based control of a compliant mechanism, is presented. In vivo experimental results are given using a prototype which structure is compatible with a minimally invasive approach.
A new Rotating Voice Coil Motor for Meteosat Third Generation satellites
19 June 2023
In the frame of the Meteosat Third Generation project (MTG), the future European Operational Geostationary Meteorological Satellites system, Cedrat Technologies has developed a dedicated actuator for the Scan Assembly mechanism (SCA) made by SENER. Such motors are needed to actuate the SCA on the north/south (N/S) and east/west (E/W) axes. The requirement of precise pointing of the SCA induces very specific characteristics for the motorisation. The motor needed characteristics are: to be free from any cogging, high constant motor [N.m/vW] to have a constant torque over full stroke range, to have a very low hysteresis and to have redundant coils. To meet these stringent requirements, the choice was made to develop a specific Rotating Voice Coil Motor.
Large Stroke Fast Steering Mirror for Space Free-Space Optical communication
2 March 2020
Free-Space Optics and Deep Space Optical Communication request new compact low-power high-stroke high-bandwidth Fast Steering Mirrors. To address this need, CEDRAT TECHNOLOGIES has developed a Magnetically-actuated Fast Steering Mirror called M-FSM, taking heritage of its MICA™ technology. This mechanism offers Rx Ry strokes larger than +/-2° with a 250Hz bandwidth when tilting a 10mm-diameter mirror. Closed loop control is achieved using integrated eddy current sensors. Requested power is reduced leading to low heating and allowing high duty cycle. Vibration tests allow to define first limits and conditions for the M-FSM to bear external vibrations.
Actuators for Space Applications: State of the Art and New Technologies
19 June 2023
Actuators in space are broadly used to operate satellites’ platform and payload devices. Despite their common utilisation, actuators still represent critical subsystems as their failure might often lead to severe, when not catastrophic, effects on the spacecraft operations. Environmental conditions to which actuators are exposed in space are generally not favourable: operating temperature ranges and deep vacuum are certainly the most critical ones.
