MCAO
AO Module Electronics
Mark Hunten
MCAO
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)
May 24-25, 2001
MCAO Preliminary Design Review
2
MCAO
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
May 24-25, 2001
•LGS WFS Zoom
•LGS WFS positioning
•NGS WFS
•NGS WFS Positioning
•Diagnostic WFS
MCAO Preliminary Design Review
3
AOM Motor Listing
MCAO
(slides courtesy of Corinne Boyer)
Device
Hardware
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.
May 24-25, 2001
MCAO Preliminary Design Review
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AOM Motor Listing, cont.
Device
Hardware
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 mask
A single DC motor with 2 limit
switches: 2 outputs and 2 inputs of a
XVME244 digital I/O card.
May 24-25, 2001
MCAO Preliminary Design Review
MCAO
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AOM Motor Listing, cont.
Device
Hardware
Inlet shutter
A single DC motor with 2 limit switches: 2
outputs and 2 inputs of a XVME244 digital
I/O card.
Output shutter
A 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.
May 24-25, 2001
MCAO Preliminary Design Review
MCAO
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AOM Motor Listing, cont.
MCAO
Device
Hardware
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 rotation
2 DC servo motors: 2 channels of an
OMS58 servo card.
DWFS probe arm
4 DC servo motors: 4 channels of an
OMS58 servo card.
May 24-25, 2001
MCAO Preliminary Design Review
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AOM Motor Listing, cont.
MCAO
Device
Hardware
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 corrector
2 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.
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
Adaptive Optics Module Electronics
AOM Motor Listing Summary
Type of control Number of
Channels
22
Number of Pins
(includes encoders
and limit switches)
400
Digital Input
38
Number of Pins for
DM
~1200
DC Servo
31
Digital Output
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
AOM Component Controller
(slide courtesy of Corinne Boyer)
Time bus
To servo motor
electronics
May 24-25, 2001
XYCOM531 D/A board
XYCOM 244 Digital I/O
OMS58 motor controller
OMS58 motor controller
OMS58 motor controller
OMS58 motor controller
Bancom 635 time board
MVME 2700 366MHz, 64 MB CPU
Control LAN
AOM VME
To switches,
relays, DC
motors
MCAO Preliminary Design Review
To slow TT
mirrors
10
MCAO
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.
5 CCDs
HVA
DMs
Servo Amp
T/T
RTC
3 x4 APDs
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
Adaptive Optics Module Electronics
Block diagram of NGS
APD WFS system.
Field Lenses
APD Modules
Gated Counters
Then we read the counters with a
Photons
are gathered
here
and sent
digital
input
card to the
VME
down the fibers.
computer.
This is used to compensate
for
NGS
tipmodules
tilt errors
The
APD
register the photons
and put out TTL pulses.
VME Rack
DC Servo Amp Modules
Fast
Tip/Tilt
Mirror
Main Tip/Tilt Mirror
Control
Input of APD counts
DC Servo Amp Modules
3 NGS XY Stage
Control
We count the events with a
gated counter so we can gather
counts per unit time
May 24-25, 2001
MCAO Preliminary Design Review
NGS WFS Stages
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MCAO
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)
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
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.
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
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.
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
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 Iq of the high voltage amps.
Example:
-Xinetics uses an amplifier that has 25 mA Iq. 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.
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
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 rack
2 - Piezo servo racks
2 - DC Servo racks
1 - DC control rack
- The total space available is 111U.
- We are using 100U
May 24-25, 2001
(1U = 1.75” – don’t ask)
MCAO Preliminary Design Review
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AOM Electronics Mass Estimate
Item
Qty
APD Modules
APD Power supply +12V\+5V\-12V 15A@+5V
DC Servo Amp
Piezo Amp
DC Servo Amp P/S ?A@+24VDC/AC
Piezo Amp P/S 20A@24VDC
3U racks for amps
SDSU Power Supplies
SDSU Shoeboxes
DM Racks
VME Rack
Network Hub and annex
DM LVPS + racks
DM HVPS + racks
12
1
26
10
2
1
3
3
3
5
1
1
3
3
Mass ea in kg Total mass in kg
0.25
3
5
5
0.35
9.1
0.35
3.5
2
4
2
2
0.5
1.5
2
6
6
18
25
125
10
10
2
2
4
12
2
6
0
0
0
Total Mass:
May 24-25, 2001
MCAO
207.1
MCAO Preliminary Design Review
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MCAO
Design Proposal for
Gemini South Adaptive Optics
Paul Clark
System Overview
MCAO
• 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)
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
Drive System Architectural Overview
May 24-25, 2001
MCAO Preliminary Design Review
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Existing 97 actuator drive system
MCAO
DAC Interface
DAC Card
HV Amplifier
May 24-25, 2001
HV PSU
MCAO Preliminary Design Review
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MCAO
Existing 25 channel HV amplifier card
(one channel populated)
May 24-25, 2001
MCAO Preliminary Design Review
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MCAO
PDR Agenda
Thursday, 5/24
0800 Welcome
0805 Project overview
0830 Science case
0930 Break
0945 System overview
1015 System modeling
1100 AO Module optics
1145 Lunch
May 24-25, 2001
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 Preliminary Design Review
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