1. FP7 LED
A.Jeremie, L.Brunetti, N.Geffroy

2. State of the art.
b) Current limitations that need to be addressed to achieve 1nm above 1Hz and 0.1nm above 5Hz.
c) Potential means to overcome these limitations.
d) A rough idea of a potential schedule. It would be useful to keep in mind that we would like to use the sensors in the project.
e) Resources needs and availability.
4) Potential programme to develop the software for the design of the module and to control the feedback. (Andrea)

3. Resonances of : -beam -support
Rejection de 6 résonances : (sans et avec asservissement) sur un petit prototype
Resonances of : -beam -support

4. Feedback output: Actuator at the fixed-part of the beam
State of the art inertial sensors
Feedback output: Actuator at the fixed-part of the beam
In nm conditions and “uncontrolled” ground motion excitation: peaks are large=> new feedback algorithm based on internal command

5. Simulation Dynamic response
with feedback
SAMCEF
External perturbation
Structure
Dynamic response
Dynamic equation
Sensors
Feedback loop
Actuators
MATLAB -Simulink

6. Current work to overcome SAMCEF/MATLAB interface difficulties
FE Model
(Super-Element)
SAMCEF
State model (A,B,C,D)
Perturbation
Mouvement
MATLAB Simulink
Control (Internal model control and/or State representation)
Sensors
Actuators
Difficulty: complexity and accuracy of mechanical model

7. - Enhance the perturbation around a given frequency fc
TMC Isolator
« Passive » rubber:
- Enhance the perturbation around a given frequency fc
- Damp perturbations above fc
Transfer function for passive material fc
« Active » :- Active isolation in the frequency range enhanced by the passive material
frequency
=>start building a prototype combining Passive and Active isolation=>develop specific feedback

8. Multisensor/multiactuator
The prototype :
Experimental results :
Actuator
Sensor
PZT0
PZTM
Optical VG G VB N
Very bad
No effect
Good
Very good
Girder behaviour changes with instrumental configuration

9. Resources needed
Human resources:
Automatics engineer : 36 months or whole 5 years?
Mechanical engineer (simulations): 12 months (50%?)
Machine shop: 6 months
Material resources:
Real-time equipment 10000euros
performing dedicated PC euros
Milestones: schedule?
Internal control under work
Multisensors/multiactuators
Feedback for mock-up
Go from small mock-up to larger one
Study passive material
Follow the FD support schedule?
the FD stability can go over the 5 years of the program.
=>construction of test stand until 2009 with specifications well understood
=>tests during 2009/2010