Integrated Type-A control meeting

To Do

Model

• Mechanical model : SUMCOM
  • Integrated model exists
  • Tuning of the model parameters for individual suspension is necessary
• Electronics model and control loop model can be implemented in the Noise Budget tool

• Existing suspension NB model

• Implement a standalone NB model for Type-A first
• Then integrate it into the IFO NB model

Sensor / actuator diagonalization

• Tower part is on going (a fair bit done already)
• CRY part will start from now
• VIS experts should join the work to expedite it

TF measurements

• Check the mechanical status of the suspension
• Base for the control
• Comparison against the model predictions

Damping control

• Except for ITMY, inertial damping is going to be completed
• Integrated work with CRY and VIS is necessary
• Modal damping for GAS (later ?)

Hierarchical control

• Procedure
  • Measure TFs from various stages to TM
  • Design blending filters to combine them
  • Iteration
  • Establishing a good suspension model is necessary in the filter design process
    • Inject seismic noise to make sure that no actuator saturate

Automatic operation

• Guardian
  • Currently fairly incomplete
  • We can get help from the Type-B team (Mark and Terrence)
• Automatic health check
• Status monitor

Desired status before Y-arm lock

• All the sensors diagonalized
• All the actuators diagonalized
• All the TFs reasonably agree with the model
• Damping control satisfies the requirements
  • Length RMS requirement
    • Since ALS will be used, there is no dynamical requirement for L
    • Saturation of the actuator while keeping the lock sets the requirement
  • Angular RMS requirement

    • Less than 880nrad JGW-T1808343

• Hierarchical control is ready
  • Maximum actuation range

    • X um: f < 0.5Hz

    • YYY nm: 0.5Hz < f < 1Hz

    • ZZ nm: 1Hz< f < 10Hz

  • Response to the feedback input is similar to a single pendulum

Schedule

• 4/1 - 4/26: ITMY suspension commissioning
• 5/7-5/10: Y-arm lock with feedback to ITMY mass

People

• Fujii
• Lucia
• Okutomi
• Ushiba
• ???