SkyMapper 1.3m Telescope: Critical Design Review, November 23 /24, 2005 © 2005 Copyright EOS Technologies, Inc. SkyMapper 1.3 Meter Telescope Critical

Welcome to the SkyMapper 1.3m Telescope Critical Design Review

EOS Space Systems Canberra 8:00 am Nov 24,

2005

EOS Technology Tucson 2:00 pm Nov 23,

2005

3SkyMapper 1.3m Telescope: Critical Design Review, November 23 /24, 2005 © 2005 Copyright EOS Technologies , Inc.

Critical Design Review Agenda

• Introduction– Teams– CDR Folder

(Documentation)

• Project Management – Program Schedule– Work in Progress

• Review of Mount Design– Overview– Base– Yoke– OSS

– Drive sizing

• Optics– Optical Tolerancing– Optical Alignment– Baffling– Optics Production

Update

• Finite Element Analysis– Eigen Frequency– M1 Support– M2 Assembly– Line of Sight

• Controls – Control Cabinet Layout

• Software– Software Architecture– Firmware– Server Applications– Client API– User Interface


Teams

Australian National University Team:

Prof Brian Schmidt Science Lead (RSAA Astronomer)

Mike Petkovic Project Manager (Auspace)

Andrew Granlund Mechanical Engineer (RSAA)

Annino Vacarella Scientific Programmer (RSAA)

Peter Conroy Designer (RSAA)

Liam Waldron Technical Programme Manager (RSAA)


Teams

EOS Space Systems Team:

Craig Smith CEO

Mark Blundell Project Manager

Andrew Rakich Optical Designer

Adam Seedsman Observatory Group Manager

Michael Forman Senior Software Engineer

Ali Avci Optical Designer


Teams

EOS Technology Team:

Rob Brunswick Program Manager

Bruce Cook Chief Technology Officer (Systems Engineering)

Ken Clarke Lead Mechanical Designer

Jim Waltho Mechanical Engineer (Finite Element Analysis)

Carlos Vanegas Mechanical Engineer (FEA and Line of Sight Analysis)

Adrian Loeff Senior Software Engineer

Aaron Evers Software Engineer

Mark Croft Electronics Associate (Controls)

Harry Fagg Project Planning and Control

Paul Sherman Senior Opto-Mechanical Engineer

Vince Blair Assembly and Test Supervisor (Assy, test, shipping,

installation)


Agenda

Project Management

• Program Schedule

• Work in Progress


Program Schedule Critical Path – CDR to Site

Milestones depend on successful completion of M1 (accelerated polishing schedule)

M1 ready to install Sept 1, 2006FAT complete Oct 31, 2006 Telescope on Site Dec 19, 2006 SAT / Final AcceptanceJan 23, 2007


Program Status

Major Milestones: Contract vs. Plan

Milestones depend on successful execution of the M1 contract with LZOS for M1 by December 5th 2005.


DocumentationSECTION 1

Critical Design Review Presentation

SECTION 2TR-9150-1 Technical and Interface Resolution ReportFEA-9267-1 Finite Element AnalysisDC-6597-2 Drive Sizing Calculation

SECTION 3SSD-8747-3 Software System Design

SECTION 4

ICD-8984-2 Telescope to Enclosure (Interface Control Document)ICD-8137-2 Telescope to Instrument/CLA (Interface Control Document)

SECTION 5OPT-10044-2 Optical ToleranceDN-500790-01 Alignment ProcedureDN-07591-02 Alignment Maintenance TargetsMRS-7790-2 Recommended Spare Parts List


Mount Design

• Overview• Base• Yoke• Optical Support Structure (OSS)

– Truss– M1 Support– M2 Support


Overview

Upper Truss

Instrument

Base

Cable ladder

Yoke

Lower Truss

Center Section

Mirror Covers


Mount Design: Base

Azimuth Slewing Ring

End of Travel Switch

Door

External Cabling Strain Relief

Center of Rotation Switch

Connector Panel


Mount Design: YokeEncoders

Fiberglass Covers

Mirror & Instrument removal rails

Elevation Stop Pin


Mount Design

M2 Baffle

Hexapod

M2 Vanes

Optical Support Structure (OSS)

Corrector Lens Assembly


Mount Design: M1 Support

Tangent Flexure ( replaced with tangential noodle flexures )

Load Spreader

Lateral Support

Lateral Support Counterweight

Lateral Support Flexure

Mirror Puck18 Point M1 Support


Mount Design: M2 Support

Lateral Support

Flexure Assembly

Load Spreader

Tangent Flexure

Mirror Puck

18 Point M2 Support


Analysis

Jim Waltho and Carlos Vanegas, Mechanical Analysts

• Drive Sizing• Eigen Frequency• M1 Support• M2 Support• Line of Sight


Drive Sizing

• Refer DC-6597-2

• Draft: PDR February 2005

• Final: CDR November 2005

• Azimuth Motor requirement: 478 Nm

• Elevation Motor requirement: 178 Nm

Continuous stall torque 1.5 times calculated torque required to produce the specified telescope accelerations, under worst case loading


Drive Sizing

Azimuth Motor:

Requirement: 478 Nm

Kollmorgan QT-23502

Continuous torque 950 Nm


Drive SizingElevation Motor:

Requirement: 178 Nm

Kollmorgan QT-12502

Continuous torque 271 Nm


Complete Telescope FEA

• Purpose of model– Create a structural representation of the telescope to

evaluate its stiffness.– Find the resonant frequencies and vibration modes.

• Model creation – Built from software model.– Shell, solid and beam elements– Weights, CG’s and inertias within 5% from software

model.• Requirements

– Structural Resonance > 8Hz.


Complete Telescope FEA

Fixed base

Yoke

Azimuth bearing

Elevation bearings

Instrument rotator

Upper truss(modeled as point mass )


1st Telescope Mode @ 8 Hz

8 Hz 24 Hz

Telescope mode Upper truss mode


M1 Support Structure FEA

• Purpose of model– Create a structural representation of the M1 Support

to evaluate its stiffness.– Find the impact of temperature change and gravity

direction over the WFE.• Model creation

– Built from SW model.– Solid, shell and beam elements.– Weights, CG’s and inertias within 5% from SW model.

• Simulation Approach– Tmin= -20°C, Tmax= 40°C, Tassy= 20°C, Δ Tmax=40°C

– Zenith and 70° orientation.



Counterweight system provides lateral support

Tangential flexures

3 count

Whiffletree vertical support

18 puck support

Lateral counterweights

6 count

Kinematic support at 3

points


M1 Wavefront ErrorZenith, ΔT=0 WFE=19.2nm

Budget Allocation55 nm





M1 Wavefront Error 70°, ΔT=0 WFE=26.2nm



M1 Wavefront Error 60°, ΔT=40 WFE=53.9 nm




• Purpose of model– Create a structural representation of the M2 Support

to evaluate its stiffness.– Find the impact of temperature change and gravity

direction over the WFE.• Model creation

– Built from software model.– Solid, shell and beam elements.– Weights, CG’s and inertias within 5% from software

model.• Simulation approach

– Tmin= -20°, Tmax= 40°C, Tassy= 20°C, ΔTmax=40°C– Zenith and 70° orientation.



CAD model FEA model





M2 Wavefront Error 70°, ΔT=40 WFE=52.3 nm



Line Of Sight Analysis

@70° Worst operation case

M1

M2

X

ZY

* Rotation in arcsec, positive out of the page while G load is down

Ux(µm) Uy(µm) Rx (arcsec) Ry (arcsec)M1 -19.8 0.48 0.01 -1.35M2 -330.2 0.20 0.01 20.17

All perturbations are within design limits except for M2 Ux, which will be corrected with the hexapod


Mirror Covers

• Stiffer mirror cover design than used on previous 1m telescopes


Controls

• Control Cabinet Layout

• Typical Rack Construction

• PMAC Channel Allocation


Control Cabinet Layout

Fans

GPSEncoder Planar 0

Blank (4U)

Panel indicators,Keyboard, et cetera

Telescope Control Computer

Digital I/O Planarand power supplies

Hexapod (4U)

Blank (4U)

Blank (6U)


Control Cabinet

FrontRepresentative Only

RearRepresentative Only


PMAC Channel Allocation

AXIS PMAC AXIS MOTOR AMPLIFIER ENCODERS LIMIT SWITCHES

Name Quantity Type Voltage Rating Quantity Type Inside COR Failsafe

Azimuth 1 DC 56 30 2 Linear Tape 2 2 2

Elevation 1 DC 56 30 2 Linear Tape 2 1 2

Instrument Rotator 1 DC 24 5 2Motor(1)

Linear Tape(1)2 1 2

Time 1 N/A N/A N/A 1 10MHz N/A N/A N/A

The Physik Instrumente hexapod has a dedicated controller and cable interface separate from the PMAC.


Software Architecture• Firmware• Server Applications• Client API• User Interface

Aaron Evers, Software EngineerAdrian Loeff, Senior Software Engineer

Software


SoftwareArchitecture

Telescope Control Computer

Customer Computer/s

DIOServer

Control System Framework

TelescopeServer

GPS TimeServer

UserInterface

CustomerSoftware

Client API

DIOBoard

PMAC

PMACFirmware

Encoder Planar 0ENCP0

Firmware

Digital I/O PlanarDIOP

Firmware

DIO

Sig

nals

Ser

voC

hann

els

GPSReceiver

Key:

Software Hardware ComputerCustomer Supplied

Product

Key:

Software Hardware ComputerCustomer Supplied

Product

TemperatureSensor Server

TemperatureSensors

Temperature Sensor Controller

…

EthernetSerial

HexapodServer

HexapodComputer

Hexapod

Serial

Ethernet


Software Architecture

– PMAC Firmware– DIOP Firmware– ENCP0 Firmware– DIO Server– Telescope Server– Hexapod Server

– GPS Time Server– Temperature Sensor Server– Control System Framework– Client API– User Interface

Based on current software architecture

Reuses these modules with minimal changes:


• No user interface; starts automatically• Monitors/controls the following servo motors:

– Azimuth– Elevation– Cassegrain instrument rotator

• Interface to TCC through Dual-Port RAM• Accepts commands from Telescope Server• Reports status to Telescope Server

PMAC Firmware

Embedded software installed on the PMAC motion control card, responsible for controlling servo motors


• No user interface; starts automatically• Interface to Encoder Planar 0• Implements safety-critical logic• Monitors/controls: mirror covers, E-stop, failsafe limits,

servo amplifier power, ancillary power, onboard fuses, and others

• Accepts commands from DIO server• Reports status to DIO server

DIOP Firmware

Embedded firmware installed on the FPGA in the Digital I/O Planar that routes and combines digital signals controlling ancillary telescope devices


Embedded firmware installed on the FPGA in Encoder Planar 0 that routes and combines digital signals relating to the control of PMAC servo channels 1 through 8

ENCP0 Firmware

• No user interface; starts automatically• Interfaces to DIOP, PMAC• Monitors/controls:

– PMAC servo channels 1 through 8: limit switches, home flags, amplifier power, faults

– digital timing signals– others

• Reports status to DIOP


Windows embedded software application which processes various digital signals in the telescope control system, many related to ancillary devices

DIO Server

• Minimal user interface; starts automatically• Interface to DIOP through DIO board• Monitors/controls: mirror covers, E-stop, failsafe limits,

servo amplifier power, encoder fault signals, and others• Accepts commands from clients to operate devices• Reports status of devices to clients• Some autonomous activities (e.g., turning off mirror

cover motors when mirror cover reaches position)


Windows embedded application, responsible for control of the telescope axes

Telescope Server - 1

• Minimal user interface; starts automatically• Interface to PMAC firmware through PMAC Dual-Port

RAM• Interface to hexapod through Hexapod Server• Interface to UTC through GPS Time Server• Provides high-level control over: azimuth, elevation,

secondary position, Cassegrain instrument rotator


Correction models for accurate positioning• Mount model• Atmospheric refraction• Thermal expansion/contraction of truss• Truss sag due to gravity• Adjust telescope pointing for M2 position

Safety features• Axis stability monitoring• Variable-height operating skyline• Sun avoidance

Telescope Server - 2


Windows embedded application that controls the position of the secondary mirror via the hexapod

Hexapod Server

• Minimal user interface; starts automatically

• Provides high-level control over the hexapod

• Accepts commands from clients to operate hexapod

• Reports status of hexapod and hexapod computer


Windows embedded application that reads the current time from the GPS receiver and synchronizes the other modules

GPS Time Server

• Minimal user interface; starts automatically• Maintains UTC time through serial connection to the

GPS receiver• Provides access to UTC time to clients• Reports status of GPS receiver to clients


Windows embedded application that reads temperature from sensors attached to the telescope structure and primary mirror

Temperature Sensor Server

• Minimal user interface; starts automatically• Interface to Temperature Sensor Controller over

Ethernet• Provides access to the temperature sensors in

the telescope structure and optics• Reports temperature, location, and status of

sensors to clients


• Module provides common services and functionality for all server applications and monitors their operation

• Consists of several different utilities that run on the control computer as well as code libraries used by the servers

• Monitors health of server applications and TCC

• Collects, caches, and distributes system performance data and server state information

• Controls configuration of the system

• Provides access to the message interface to all servers for engineering purposes

Control System Framework


• Interface between the telescope control system and the outside world

• Consists of library modules that can be imported into customer software to control the telescope

• Defines the format/structure of the messaging system

• Implements the transport layer

• Defines behavior of clients and servers

• Implemented using Device Meta Language (DML)

Client API


• Messages are sent using the Client API• Starts up on demand• Accepts commands from the user to operate the

entire telescope control system• Reports status of the entire telescope control

system to the user• Provides access to the Client API low-level and

high-level messages• Runs on Linux and Windows• Configurable

Graphical User Interface

Provides an operator with the ability to monitor and control the entire telescope system


Agenda

Next Session:

Optical Design – Andrew Rakich

• Optical Tolerancing

• Optical Alignment

• Baffling

• Optics Production Update

Documents

SkyMapper 1.3m Telescope: Critical Design Review, November 23 /24, 2005 © 2005 Copyright EOS Technologies, Inc. SkyMapper 1.3 Meter Telescope Critical