Micropositioning
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Contactless Torque Sensors based on shaft torsion measurement, compatible with existing shafts
19 June 2023
The torque measurement usually comes from strain gauges bonded on a shatf. the main concern in this measurement is due to the fact that these gauges are also rotating and the integration of electronic on rotating parts is definitely a blocking point.
Advanced Landing Gears for Improved Impact Absorption
6 January 2008
The presented project ADLAND (AST3-CT-2004-502793) dealt with evaluating the options for adaptive shock absorbers to be applied in aircraft landing gears. Analytical design procedures were developed to simulate different potential design options and a best practice solution determined. The different hardware components regarding adaptive shock absorbers were then developed and tested with regard to adaptive landing gear model. The objectives of the project were: to develop a concept of adaptive shock-absorbers, to develop new numerical tools for design of adaptive absorbers and for simulation of the adaptive structural response to an impact scenario, to develop technology for actively controlled shock-absorbers applicable in landing gears, to design, produce and perform repetitive impact tests of the adaptive landing gear model with high impact energy
dissipation effect, to design, produce and test in flight the chosen full-scale model of the adaptive landing gear.
Aero India 2003 Piezo actuators air & space
19 June 2023
Several classes of Piezo Actuators based on low voltages piezo ceramics have been developed by CEDRAT TECHNOLOGIES in order to cover needs for long stroke, precise and/or fast positioning in the fields of air & space applications. A specific class of Amplified Piezo Actuators, so called APA has been patented, developed and qualified. Their applications concern subjects as various as Scientific Instruments for Space payloads (Telescopes, Microscopes), Micro-Satellites Propulsion Valves or Active flaps of Helicopter Blades.
Control of magnetic actuators in electric contactors by current shapping
19 June 2023
Most of present electric contactors use magnetic actuators of reluctant type (so called electromagnets) that are supplied with a simple voltage source. The use of a reluctant actuator in this condition leads to a considerable force increase when the magnetic circuit is closing, which creates damaging rebounds of the electrical contacts. To have a better control of the closing dynamics, we develop an electric drive method to reduce impact speed and to improve the closing dynamics. In this method, the reluctant actuator structure is unchanged. The appropriate current shape to be injected into the actuator is determined using a calculation method.
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].
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.