MCAO AO Module Electronics Mark Hunten

MCAO May 24-25, 2001MCAO Preliminary Design Review2 Adaptive Optics Module Electronics The Adaptive Optics Module (AOM) Electronics can be broken into 3 major subsystems: LGS CCD system Deformable Mirrors AOM control (everything else)

MCAO May 24-25, 2001MCAO Preliminary Design Review3 Adaptive Optics Module Electronics AOM control This covers the control system for most of the AOM. The system will control: Source Simulators Shutters Main Tip/Tilt Mirror Science Beamsplitter Science ADC NGS ADC LGS WFS Zoom LGS WFS positioning NGS WFS NGS WFS Positioning Diagnostic WFS

MCAO May 24-25, 2001MCAO Preliminary Design Review4 AOM Motor Listing (slides courtesy of Corinne Boyer) DeviceHardware LGS simulated source array illumination One output channel of a XVME244 output card. LGS simulated source array position A single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. LGS simulated source array focus A single DC servo motor: one axis of an OMS58 servo card. NGS peripheral simulated source array illumination One output channel of a XVME244 output card. NGS central simulated source array illumination One output channel of a XVME244 output card.

MCAO May 24-25, 2001MCAO Preliminary Design Review5 AOM Motor Listing, cont. DeviceHardware NGS simulated source array position A single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. LGS reference source array illumination One output channel of a XVME244 output card. LGS reference source array position A single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. DM0 maskA single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card.

MCAO May 24-25, 2001MCAO Preliminary Design Review6 AOM Motor Listing, cont. DeviceHardware Inlet shutterA single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. Output shutterA single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. Beam splitter wheel A single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card.

MCAO May 24-25, 2001MCAO Preliminary Design Review7 AOM Motor Listing, cont. DeviceHardware Science ADC position A single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. Science ADC rotation 2 DC servo motors: 2 channels of an OMS58 servo card. NGS ADC rotation2 DC servo motors: 2 channels of an OMS58 servo card. DWFS probe arm4 DC servo motors: 4 channels of an OMS58 servo card.

MCAO May 24-25, 2001MCAO Preliminary Design Review8 AOM Motor Listing, cont. DeviceHardware Diagnostic camera mirror A single DC motor with 2 limit switches: 2 outputs and 2 inputs of a XVME244 digital I/O card. LGS zoom corrector2 DC servo motors: 2 channels of an OMS58 servo card. NGS WFS probe arms 6 DC servo motors: 6 channels of an OMS58 servo card. Pupil alignment mirrors Piezzo-electric actuators: 10 output channels of a XYCOM 531 DAC. LGS active relay elements 15 DC servo motors: 15 channels of an OMS58 servo card.

MCAO May 24-25, 2001MCAO Preliminary Design Review9 Adaptive Optics Module Electronics AOM Motor Listing Summary Type of controlNumber of Channels Digital Output22 Digital Input38 DC Servo31 Number of Pins (includes encoders and limit switches) 400 Number of Pins for DM ~1200

MCAO May 24-25, 2001MCAO Preliminary Design Review10 AOM Component Controller (slide courtesy of Corinne Boyer) MVME MHz, 64 MB CPU Bancom 635 time board OMS58 motor controller XYCOM 244 Digital I/O Control LAN Time bus To servo motor electronics To switches, relays, DC motors To slow TT mirrors XYCOM531 D/A board OMS58 motor controller AOM VME

MCAO May 24-25, 2001MCAO Preliminary Design Review11 5 CCDs Adaptive Optics Module Electronics RTC System Interface The High Voltage Amplifier (HVA) part of the system is controlled by RTC which reads the 5 CCDs, computes the corrections and then sends the corrections to the digital interface on HVA for the DMs. That interface takes the digital information and converts into analog which is then scaled to the high voltage needed to drive the DMs –> 40 to 100VDC. RTC HVADMs Servo Amp T/T3 x4 APDs

MCAO May 24-25, 2001MCAO Preliminary Design Review12 Adaptive Optics Module Electronics Block diagram of NGS APD WFS system. Photons are gathered here and sent down the fibers. The APD modules register the photons and put out TTL pulses. We count the events with a gated counter so we can gather counts per unit time Then we read the counters with a digital input card to the VME computer. This is used to compensate for NGS tip tilt errors

MCAO May 24-25, 2001MCAO Preliminary Design Review13 Adaptive Optics Module Electronics LGS CCD system Study was done by HIA on low noise rapid readout CCD systems. Conclusions are presented in Appendix O. The system presented today has 5 80 x 80 CCDs read out at frame times of less than 1 ms. (2 CCDs not shown for clarity)

MCAO May 24-25, 2001MCAO Preliminary Design Review14 Adaptive Optics Module Electronics LGS CCD system Proposed system uses SDSU second generation controllers with the new high speed fiber optic links to transfer data at 12.5MPix/s. This system would require one interface card to reach the desired 7.5 Mpix/s rate for the 5 80x80 CCDs with <1ms readout rate. SDSU is presently working on a PCI version of the high speed interface card, with the desired PMC version due out soon after. The controller would have 10 dual video cards to read the 5 CCDs but using only one timing card to lockstep the readout. There would also be one utility card.

MCAO May 24-25, 2001MCAO Preliminary Design Review15 Adaptive Optics Module Electronics Deformable Mirror Electronics Two designs have been evaluated as possible approaches so far. Others are available. - Xinetics high voltage amplifiers. - University of Durham high voltage amplifiers. The approach from the University of Durham has lower power dissipation.

MCAO May 24-25, 2001MCAO Preliminary Design Review16 Adaptive Optics Module Electronics AOM Power dissipation The DMs have a drive system that is different than what we are used to. There is a quiescent power dissipation which depends on the I q of the high voltage amps. Example: -Xinetics uses an amplifier that has 25 mA I q. This, times the number of channels (1058) gives us just over 2kW of power while it is sitting there. This goes up when we move at higher frequencies. If we reduce this to 2.5 mA, the power goes down by a factor of 10. This is the main heat source for MCAO. The rest of the electronics is estimated to dissipate 1kW. The worst case total would be over 3kW.

MCAO May 24-25, 2001MCAO Preliminary Design Review17 Adaptive Optics Module Electronics AOM Space Usage The volume of the DM system is 5 9U racks. Two each for the larger DMs and one for the smaller. Power supplies are in addition to this. The 2 VME racks take 9U each. A network interface takes 2U The rest of the system is made mostly of 3U racks. 1 - APD Interface rack2 - Piezo servo racks 2 - DC Servo racks1 - DC control rack - The total space available is 111U. - We are using 100U(1U = 1.75” – don’t ask)

MCAO May 24-25, 2001MCAO Preliminary Design Review18 AOM Electronics Mass Estimate

MCAO Design Proposal for Gemini South Adaptive Optics PaulClark Paul Clark

MCAO May 24-25, 2001MCAO Preliminary Design Review20 System Overview Compact, scalable design Based on existing, proven equipment Incorporates DAC interface, DAC and HV amplifier cards Total volume 45U 19” rack space (excluding power supplies and ventilation) Heat load 820W (approx)

MCAO May 24-25, 2001MCAO Preliminary Design Review21 Drive System Architectural Overview

MCAO May 24-25, 2001MCAO Preliminary Design Review22 DAC Interface DAC Card HV Amplifier HV PSU Existing 97 actuator drive system

MCAO May 24-25, 2001MCAO Preliminary Design Review23 Existing 25 channel HV amplifier card (one channel populated)

MCAO May 24-25, 2001MCAO Preliminary Design Review24 PDR Agenda Thursday, 5/ Welcome 0805 Project overview 0830 Science case 0930 Break 0945 System overview 1015 System modeling 1100 AO Module optics 1145 Lunch 1245 AO Module mechanics 1340 AO Module electronics 1400 Break 1415 Beam Transfer Optics 1510 Laser Launch Telescope 1545 Closed committee session 1800 Adjourn

MCAO May 24-25, 2001MCAO Preliminary Design Review25 Adaptive Optics Module Electronics ADCs and Diagnostic WFS position servo control block diagram.

MCAO May 24-25, 2001MCAO Preliminary Design Review26 Adaptive Optics Module Electronics Block diagram of DC Motor control

MCAO May 24-25, 2001MCAO Preliminary Design Review27 Beam Transfer Optics Electronics Overview of the BTO diagram. BS Pointing Array (PA) Top-End Ring Mirror KM LLT Center Section Top End Relay BDS Centering mirror (CM) Fast Steering Array Pointing mirror (PM) Centering Array (CA) X-Shaping Mirrors

MCAO May 24-25, 2001MCAO Preliminary Design Review28 Beam Transfer Optics Electronics The Beam Transfer Optics control consists of items that are on the main part of the telescope. These would include: Pointing Mirror Centering Mirror K Mirror Quarter Wave Plate Corner Cube Shutter Top End Ring Mirror Pointing Mirror Array Centering Mirror Array Fast Steering Mirror Array Near Field Chopper Wheel Near and Far Field Cameras Polarization Sensor

MCAO May 24-25, 2001MCAO Preliminary Design Review29 Beam Transfer Optics Electronics The Beam Transfer Optics also has some items that are not in the main control loop. These are under user control and mostly for monitoring purposes: Beam Dump Mirror Power Meter (part of Beam Dump Mirror) Alignment Camera selector (for 3 cameras)

MCAO May 24-25, 2001MCAO Preliminary Design Review30 Beam Transfer Optics Electronics Some general notes: The Beam Transfer Optics control electronics would be located on the main part of the telescope, probably on the Center Section. These would be located in a thermal enclosure to keep the radiated heat to a minimum. Items in the enclosure would be the VME control computer, servo control electronics, mechanism control electronics, monitoring electronics and camera interfaces.

MCAO May 24-25, 2001MCAO Preliminary Design Review31 Beam Transfer Optics Electronics More notes: System is distributed on the telescope from the center section to the top end. This will require substantial coordination with the telescope operations groups for the installation period.

MCAO May 24-25, 2001MCAO Preliminary Design Review32 LGS Readout, Zoom Correction and DM control block diagram. Fiber optic

MCAO May 24-25, 2001MCAO Preliminary Design Review33 Adaptive Optics Module Electronics AOM Motor Listing

MCAO May 24-25, 2001MCAO Preliminary Design Review34 Adaptive Optics Module Electronics AOM Motor Listing

MCAO May 24-25, 2001MCAO Preliminary Design Review35 Notes on APD interface – parallel w/counters? Notes on sdsu card complement Hva interface? T/T mirror interface Include only APD block diagram VME backplane slides from Corinne?