Chinese SONG progress and its design introduction Guomin Wang Nanjing Institute of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology SONG 4 th Workshop College of Charleston

Outline:  Progress introduction  Telescope design introduction

PROGRESS INTRODUCTION

August 13, 2010: Finished the PDR

December 25, 2010: Finished the CDR

Now, we are… Structure constructing

Now, we are… mirror fabrication Mirrors material test report from Russia LZOS Preparing

Large bearing manufacturing Azimuth bearing φ680 × φ880 × 80 Delivery time: 4 months

Large bearing manufacturing Altitude bearing φ240 × φ320 × 38 Delivery time: 4 months

Preparing contract for long-term elements, such as... Torque motors Encoders

Telescope schedule ItemScheduleStatus Preliminary Design ReviewAug., 2010Closed Critical Design ReviewDec., 2010Closed Factory AcceptanceNov., 2012On going Ready for ShipmentDec., On site AcceptanceApr.,

TELESCOPE DESIGN INTRODUCTION

General requirements Cassegrain system; M1: paraboloid, 1m clear aperture, Zeodur material, active support and close-loop controled through S-H; M2: hyperboloid, fused silica material, active positioned by 5- DOF unit; M3: flat mirror, Zeodur material, 180°turn to direct the light to different Nasmyth platform; System ratio: F/36.7;

General requirements Image quality: 80% energy encircled in lucky imaging focus ； Nasmyth focus: VIS camera ( nm), RED camera ( nm), Focus monitoring camera (< 450nm), auxiliary focus; Nasmyth: R32.52″ ； Coudé focus: spectrograph ( nm); Coudé: 10″ ； ADC: doublet prism; Optical derotator: three - mirror

General requirements Range of azimuth: 0 º ～ ±220º; Range of altitude: 10 º ～ 89º Max. acceleration: 2 º/sec 2 ; Max. pointing speed: 20 º/sec; Blind spot: 2 º (diameter); Tracking accuracy: RMS 0.3″, 90s, no guiding ； Pointing accuracy: RMS 5″, 70 º ≥ ZD ≥1 º; Repeat pointing accuracy: ≤ RMS 1″, 70 º ≥ ZD ≥1 º; First frequency: large than 8 Hz;

General view

F/36.7 layout

F/36.7 parameters ItemParameters M1ф1000 Primary ratioF2.3 System ratioF Primary focus length2300 System focus length （ λ=546.1nm ） FOVR32.52″ M1-M2 distance2100 mm M2–M3 distance1600 mm M3–focus distance mm Working wavelength VIS （ λ=450 ～ 650nm ） RED （ λ=650 ～ 1000nm ）

F/36.7 imaging quality after ADC Spot diagram of ZD = 5 °

F/36.7 imaging quality after ADC Spot diagram of ZD = 45 °

F/36.7 imaging quality after ADC Spot diagram of ZD = 75 °

F/36.7 imaging quality after ADC Spot diagram of ZD = 5 °

F/36.7 imaging quality after ADC Spot diagram of ZD = 45 °

F/36.7 imaging quality after ADC Spot diagram of ZD = 75 °

Nasmyth optical design From telescope To Coudé

Nasmyth structure

Coudé optical design From telescope

Coudé structure

Optical elements list Item Size （ mm ） MaterialCoatingAccuracyQty. M1φ1030x75ZeodurAL λ/50 1 M2φ96x25Fused silicaAL λ/60 1 M3φ76X15 ZeodurAL λ/60 1 M4φ30x5ZeodurAL λ/60 3 M5φ54x8ALZeodurλ/605 Wedge prism φ40x6, ∠ 5° H-LAK10/H- ZF nm antireflection λ/60 2 K mirror 160x44x10ZeodurAL λ/60 2 K mirror 236x30x8ZeodurAL λ/60 1 Dichroic mirror 1 φ30x3Fused silica nm (R) nm (T) λ/30 1 Dichroic mirror 2 φ30x3Fused silica nm Half-reflection λ/30 1

ItemSize （ mm ） CoatingMaterialAccuracyQty. Field lens 1φ20x4AntireflectiveH-K9LN=1, ΔN=0.11 Field lens 2φ20x5AntireflectiveH-K9LN=1, ΔN=0.11 Achromatic lense1φ20x7.5AntireflectiveH-K9L/H-ZF2N=1, ΔN=0.21 Achromatic lense2φ20x7.2AntireflectiveH-K9L/H-ZF2N=1, ΔN=0.21 Achromatic lense3φ38x7.5AntireflectiveH-K9L/H-ZF2N=1, ΔN=0.21 Achromatic lense4φ22x7AntireflectiveH-K9L/H-ZF2N=1, ΔN=0.21 Achromatic lense5φ24x9AntireflectiveH-K9L/H-ZF2N=1, ΔN=0.21 Achromatic lense6φ22x7.2AntireflectiveH-K9L/H-ZF2N=1, ΔN=0.22 Protect mirrorφ54x8AntireflectiveFused silicaλ/103 Dichroic prism32x32x3 2 AntireflectiveFused silica λ/10 ± 10″ 1 Dichroic mirror 4φ32x3Half-reflectiveFused silicaλ/101 Tilt mirrorφ32x5Al nmZeodurλ/201 Filterφ22x nmFused silicaλ/103

Basement Structure Constrained the 8 fixed anchor bolts; Applied 3.5 t on the bearing place to simulate the above weight; Apply 1g on the structure; Apply 700N on the place of 1373mm from the bearing to simulate the wind force at 15 m/s; Max. stress: MpaMax. deformation: mm

Levelness adjustment Rated load (N) Max. load (N) Unit torque (Nm/10 4 N) Adjustable height of adjusting bolt (mm) Adjustable height (mm) Unit weight (kg) Table 2-1 Parameeters of iron pad

Azimuth bearing Type Crossed roller bearing d680 mm D880 mm H80 mm Axial runout< 0.02 mm Radial runout< 0.02 mm Axial sitffness5000 N/m Radial stiffness10000 N/m Tilt stiffness Nm/mrad

Azimuth encoder

Azimuth motor  Friction torque: 67.5N.m ；  Inertial torque: 50N.m ；  Wind torque: 139N.m ； Swiss Etel Company: TMB ; Rated torque: 561Nm; Rated current: 11.3A;

Max. deformation: 0.042mm  Constrain nodes connecting to bearing;  Add 1180N on top surface of center section to simulate the above weight;  Add 5390N on the down surface to simulate the down weight;  Add 1g to the structure;  Apply 400N at the place of 149.5mm above center section to simulate the wind force; Max. stress: Mpa

M1 support ￠ 1010mm, thickness 45mm, center hole 65mm, flat bottom; Axial supporting: Fixed supporting: 3; Pneumatic active supporting: 33 (6+9+18); Lateral supporting: 10 counterweight level; R1 = mm, F1 = N ; R2 = 296.5mm, F2=31.183N; R3 = mm, F3=36.775N;

Mirror cell calculation Max. stress: 2.9 MPaMax. deformation: 0.58 um

Force actuator Diaphragm Air Cylinder(Bellofram)

Electro- pneumatic regulator SMC Regulator

Force sensor

M2 positioning unit Δx (ΔY)±7 μm ΔZ±3μm Δθx(Δθx)±20″

43 M1-M2 offset calculation θ° uy （ um ） uz （ um ） Rotx(″) Uz-altitute angleUy-altitute angle Rotx-altitute angle

Frequency calculation ModeFrequency (Hz)Mode shape 124.8Fork lateral 226.8Fork fore-and-aft 346.4Truss lateral 452.2Truss fore-and-aft 554.5Top ring torsion 673.7Center section

Control architecture

TCS configuration Master Computer (Advantech Industrial PC) Slave Computer(UMAC)

M2 control configuration

Communication

3-D Of SONG telescope

THANK YOU !!!