1. Hawkeye Mechanical Design Snapshot
Compiled March 10th, 2016

2. Overall Mechanical Requirements
House the optics
Connect the instrument to rails and spacecraft
Fit within overall length of payload.
Position CCDs and get their heat out
Provide a shutter for dark frames
Support the Finder Scope assembly
Maintain a light tight package around sensors
Support the circuit boards
Implement materials and finish for thermal control
Distribute heat by creating thermal paths
Meet weight budget

3. Optical Design Concept – 8 Arrays

4. Mechanical Design Concept
Science Apertures
Finderscope
Aperture
Solenoids for shutter
Shutter Vane
Interface to
CubeSat
Circuit Cards
Debug Port

5. Payload Illustration
Within Rails Without Rails

6. Payload Length Payload length is at 4.200 inches or 106.68 mm
A protrusion of inches or 3.8 mm is needed for finderscope board. This protrusion will lie within the SIR bracket.

7. Payload to Platform Interface
16x Rail
Attachment (4 per rail)
4x End Plate attachment

8. Interface to Platform Endplate
Location of four attachment holes on Endplate.
We will provide four M2 threaded holes.
Holes not symmetric. Will need to know final orientation. 1 2 3 4

9. Interface to Platform Rails
Total of 16 attachment points to Platform rails.
We will provide 16 threaded M2 holes. Eight holes per each of two End Caps.

10. Payload to Platform Interface
Based on the configuration of the Payload it was determined that directly mounting to the Platform rails was the best option.
Mounting locations based on solid models provided by Clyde Space.
Areas requiring clearance such as protruding screw heads on the SIR mounting brackets have been noted.
Clyde Space requires a 1 mm clearance between Payload and Platform structure for vibration purposes.

11. Interference Clearance
Clearance of 3.5 mm for four stack termination screws will be provided to clear screw head height of 2.5mm. This screw is located on the Clyde Space mounting bracket.

12. Interface Issues to Address
Space and location of cable routing needs to be determined.
Due to the non symmetric mounting holes on the End Panel and SIR Mounting Bracket, orientation of those pieces will need to be communicated so we can place our attachment points.
The location of the sun sensor will have to be determined so we can design for it. It was mentioned that a smaller sensor might be used.

13. CCD Parts Stack, Top to Bottom
CCD Stack Assembly
CCD Parts Stack, Top to Bottom
Lightshield *
CCD
Pedestal
CCD Board
* Held in by two 2-56 flat head Phillips screws using two threaded swages.

14. “Finderscope” Assembly
Field Of
View
RG 830 Filter
Lens Elements
Micron 752x480 Pixel CMOS
Sensor

15. Circuit Card Configuration
Motherboard
Picozed
Board
CCD Board
Finderscope
sensor
Analog
Board
Interface
Board

16. Circuit Board Placement
Circuit boards will be attached directly to the housing or to each other by way of threaded stand offs and threaded swages
Board spacing was based on connector spacing and board proximity to mechanical components and payload edges. Space is very limited.

17. Thermal Considerations
Heat sinking rails will be used on the Analog and Mother board.
Heat sinking will be needed to dissipate heat from four CCDs.
Additional heat sinking will be required on the PicoZed board due to heat produced by Zynq processor. We plan to create a heat sinking surface on main housing that contacts processor.

18. Materials and Finish
The majority of parts will be made of standard Aluminum 6061-T6.
The optic barrels will be made of Stainless Steel due to the lower expansion properties.
Exterior surfaces will be gold plated to take advantage of the thermal properties. These include the end pieces and cover plates.

19. Payload Weight Breakdown
qty
lbs.
Total lbs
lbs Kg
Shutter
Solenoids 2
0.049
0.098
Solenoid Bracket 1
0.014
Vane
0.0118
Arm
0.0026
Brackets
0.0067
0.0134
Fasteners (ss) 8
0.0024
0.0192
0.159
Optics
Scrambler Wedge
0.0079
0.0632
Filter 2
0.0039
0.0312
Lens 1
Lens 2
0.0013
0.0104
Lens 3
Barrel (ss)
0.0156
0.1248
Adjustment sq
0.2724
CCD Assy
ccds 4
0.0119
0.0476
Pedestal
0.0073
0.0292
Lightshield
0.0057
0.0228
0.0996
Boards
Pico Zed
0.139
Board CCD
0.066
Board Analog
0.125
Board Interface
0.044
Board Mother
0.099
0.473
Enclosure
Side cover Long
0.038
0.076
Side cover Short
0.05
Sides ends
0.104
0.208
Top Baffle
0.03
Housing
0.41
Baffles
0.005
0.02
Filter Housing
0.08
0.874
Finderscope
ccd
0.0078
Board
0.0022
Lenses
0.0322
TOTALS:
1.910
0.866
Payload Weight Breakdown
Weight chart is divided into subassemblies and component groups.
Current total weight estimate is Kg
The majority of weight changes will occur in the Enclosure components.

20. Weight Budget Currently the estimated weight of payload is 0.866 kg.
Most of the weight is concentrated in the mechanical structures. Total payload weight will be controlled here.
Circuit Board weights will need to be revisited after prototype boards are made. Numbers not expected to change too much.
Weight of following should not change since design is determined.
Shutter Assembly
Optical Assembly
CCD array assembly (Includes lightshields and pedestals)
Finderscope

21. Instrument fits within CubeSat Envelope