dino peer review 13 november 2015 mechanisms shilling, tim martinez, michael

DINO Peer Review April 21, 2023

Mechanisms

Shilling, Tim

Martinez, Michael

Colorado Space Grant Consortium 2


IntroductionIntroduction

• Mechanisms includes restraints and release for:– COMM Antennas– Aerofins– FITS thin film solar arraysThe mechanisms will release the deployables in a predetermined

order– Tip mass– Antennas– FITS– Aerofins

• The restraint mechanisms are based around Planetary Systems’ Lightband, Starsys’ HOP (High Output Paraffin Actuator) and TiNi Aerospace’s Frangibolt



Requirements Imposed on Mechanisms

• Must retain mechanisms in a failsafe manner• Must release the deployables in a reliable

fashion• Must release the deployables in the order

discussed on the previous slide • Must meet power and thermal requirements



Requirements Imposed on Others• 6 Hi/Low lines to signal different stages of deployment

– Aerofins Released: 2– FITS Released: 2– Boom Released: 1– Antenna Released: 1

• 1 HOP requiring 18W at 28V for 1.5-2 minutes– Antenna Release

• Lightband separator requiring 10W @ 12V for 1 minute (May Change) – Tip Mass Release

• 4 Frangibolts 25W @ 28V for 30 Sec– FITS and Aerofins

• 4 composite hinges requiring 10W @ 28V for 1 minute– Two per Aerofin– Two Aerofins

• Thermal control of composite hinges (maintain hinge temperature between 88 and 92 deg. Celsius by cycling power to hinges)

– Minimum of two controls, one per aerofin– Requires data lines for two thermal couple (Sampling once per second)



Lightband

• 15 inch motorized separation system

• Delta V = 2 ft/s• m ≈ 6.5 lbm• Tip-off rate < 1º/s• Flight proven

– Deployed Starshine-3 satellite from Athena launch vehicle in 2001



Thin Film Solar Array (FITS)Thin Film Solar Array (FITS)

Responsibility

Microsat

• FITS

• Restraint Panel

• Deployment Hinges

CSGC

• Restraint/release system hardware

General

• Provided by Microsat

• Released with the in-house release system (IRS)

• Preloaded to 100lb

• Upon Release deployment is almost instantaneous



Flow Chart - FITS

Input and Control

Frangibolt 125 watts @ 28V

High/Low output(Switch signaling final

released position)



released position)



FITS System - Stowed Stowed Solar Array Envelope

(0.318 x 0.184 x 0.033 m)Volume = 0.0019 m3 / Wing

(0.067 ft3) / Wing

Deployment Hinge

Restraint Panel

Separation Device



Deployed driving requirements - Power - 13 Vdc and 60 Watts @EOL

Deployed Solar Array1.10 m2 / Wing Fold Integrated Thin Film Stiffener (FITS) Stainless Steel CIGS Array

85 Watts BOL - AMODeployed Solar Array Meets All Requirements

1.257 m

0.439 m0.439 m

1.636 m

FITS System - DeployedFITS System - Deployed



Frangibolt



Specifications



AerofinsAerofinsGeneral

•2 Composite panels

•Solar Arrays mounted to Panels

•Deployed with 4 composite hinges from CTD

•Held down by Frangibolts

•Deployed separately

Responsibility

CTD

• Composite aerofins

• Composite Hinges

(With Mounts)

• Ability to interface with Restraint/release system hardware

CSGC

• Restraint/release system hardware



Flow Chart - Aerofins

Input and Control

Aerofins


Composite Hinges10 watts @ 28V per Hinge for 1 minute

2-4 Hinges required


deployed position)

High/Low output(Switch signaling final released position) and

turns off Frangibolt



Composite Hinges

• Provided by Composite Technology Development (CTD)• Rigid in cooled State• When Heated returns to Original Shape• 4 composite hinges requiring 10W @ 28V for 1 minute



Aerofin Deployment / Stabilization

Major Cone

Major Cup

Aerofin

Minor ConeMinor Cup

Side Panel

Frangibolt Housing



Iso~Grid Mounting

•Minimal reduction in Iso~Grid strength.

•Central Cup spreads load stress over wider area, reducing flex on Aero~Fin.

•“Four Point” minor cones provides horizontal & vertical stabilization.



Cup Cones



Central Cup & Actuator Housing

•Frangi~Bolt Actuator captive in housing.

•Two Disc Springs to absorb energy of Frangi~Bolt Release.

• All Materials 6061 AL



Central Cone

•Two Piece Mount (6061 Al) w/ one Disk Spring to absorb energy of Frangi~Bolt Release

•Disk Spring transmits energy to rear plate, which spreads force over wider area, reducing shock to Aero~Fins.

•Cone material:Delrin 500



Disk Spring Data

Size & deflection are two Major advantages vs. conventional Spring.

Three Spring Disk @ 0.240in vs. Two standard springs @ 2.000in



Antenna Release System - HOP

• Pin Puller• Less then 120g• 50 lbs of force• One HOP releases

Antennas• Total travel of HOP release

Pin: .3in• Activated with 28V at 18 watts for 2 minutes,

which heats up the wax inside the piston, expanding

it and causing the pin puller to move



Testing Plan - Aerofins

Aerofin Structure

Sled Air table

CTD Hinge

StructureAir table

Sled



Testing Plan - Release System

• Fit test

•Composite hinges

•Structural

•Fangibolt

• Hanging Weight test

• Preloading

• Shock absorption

• Damage to Hinges?

• Environment

• Warm hinge release system deployment

AerofinStructure

SledAir table

CTD Hinge

Structure

Air table



Parts ListIn-House

•Testing equipment

•FITS

•Aerofins

•Release system

•Outsourced springs

•Aluminum parts

Outsourced

•Aerofins: Free

•HOP: Free

•FITS: Free

•Arrays

•Hinges

•3 Fringebolt: Free

•Actuator

•6 bolts: $100 each

•Reset Tool: TBD

•Tip mass

•Lightband

•Tether



Issues and Concerns (Things to be done)

• To get to CDR– Complete Prototyping

• How did the Release systems perform

– Testing to insure functionality, at least in std atmospheric conditions

– Antenna release design– Documentation– Fits release system, How does Microsat want to deal

with the Frangibot?


Structures

Shilling, TimMcArthur, GraysonSchumacher, Ted

Ko, PaulJones, Robert



IntroductionIntroduction

• Structures is to interface and house all components onto a common chasse.

• Structures will protect components from the space and launch environment, including but not limited to vibration, impact and radiation hazards.

• Structures is to interface to the ICU via Lightband as well as provide interface for the Tip mass.

• Structures will provide casing and structural connection for all components (Electronics, batteries, solar arrays, ect.)



Requirements Imposed on Structures

• Entire Structure with mechanisms will be less then 9.19 Kg

• Fixed base Natural Frequency > 100Hz at the Shuttle interface plane (SIP).

• Center of mass is to be no more then .25in from centerline and 12in from the SIP.

• Structural Ground will be isolated from Electrical Ground

• Structure must be electrically continuous (less then 1 ohm resistance)

• Structure will be coated to ensure against electrical shorting

• The completed satellite must fit within ICU envelope

• Structures must provide enclosures (As necessitated) and structural support to all electrical components.

• Structures must provide mounting for surface mounted solar arrays, aerofins, FITS and antennas (As necessitated)

• Meet all Safety concerns applicable to shuttle flight



Requirements Imposed on Others

• All systems will meet allocated size and mass budgets

• No component may have a width > 8.5in or a height > 11in

• Components may not be greater then 2in deep without prior approval from Structures and Systems



ICU Envelope



Exploded View

FITS Aerofins Power Panel

COMM

Cameras

C&DH + ADCS

Antenna Release



Main Structure

• Mass: 3.52kg• Height:12.25in • Diameter: 17.32in• Material: Al 6061• Similar design to Three

Corner Satellite



Nadir Plate

• Iso-Grid Design• Mounting plate for

Lightband systems



Side Panels



Finite Element Analysis

• Analyze the Isogrid structure to get an idea of its performance before building a test specimen.

• Examine the trade off between total mass and stiffness

• Requirements– Stiffness: Fundamental frequency > 100 Hz.– Withstand a 20 G force in each direction



Model Details

• Global size = 3.0328 mm• Tolerance = 0.15164 mm• Touching faces bonded• Material: Al 6061 linear elastic isotropic• Jacobian 4pt check• Restraints set as immovable (no translation)• Restraints located at each of the 8 mounting wholes• 20 G force acting through the center of gravity



General Drawings

Isogrid side

Back of panel

Isogrid with Outer PlateIsogrid



Design Options• Option 1

- 0.25 in. thick panel with no outer plate- mass = 0.339 kg- Stiffness = 278.16 Hz.

• Option 2- 0.125 in. thick panel with no outer plate- mass = 0.170 kg- Stiffness = 147.59 Hz.

• Option 3- 0.20 in. thick panel with 0.05 in. thick outer plate- mass = panel + outer plate = 0.272 + 0.223 = 0.495 kg - Stiffness = 295.71 Hz.

• Option 4- 0.075 in. thick panel with 0.05 in thick outer plate- mass = panel + outer plate = 0.102 + 0.223 = 0.325 kg- Stiffness = 139.95 Hz.



Chosen Design

• Option 1

- 0.25 in. thick panel with no outer plate

- mass = 0.339 kg

- Stiffness = 278.16 Hz.

• Offered the best trade off between mass and stiffness.

• Easy to manufacture because one does not have to worry about leaving an outer wall.



Analysis

• Stress calculated for a 20 G force acting solely in one of the three axis

• Stress calculated in von Mises stress (N/m^2)• Design check plot generated for FOS of 2 based

on stress• The stress plots also resemble the scaled

deformed shape



Plots for Y DirectionStress Design Check

Red < FOS = 2 < Blue



Plots for X DirectionStress Design Check




Plots for Z DirectionStress Design Check




Plot Interpretation

• All of the design check plots show the entire panel in blue, meaning that all areas equal or exceed a factor of safety equal to 2

• These two types of plots prove the side panel will withstand the 20 G forces



Issues and Concerns

• Meshing the structure as a whole, including all side panels, top and bottom plates. Several attempts have been made with multiple problems.

• How to simulate the boxes attached to the structure.– Point mass or Sheet mass



Drawing Package



ADCS + C&DH Box Design



Camera Box Pieces

Outer Box-Holds camera at ? deg angle -Allows access to USB port and power supply-Protects circuit board-- 1/8 in. thick walls

Camera Bracket

-Secures camera in box

-Supports circuit board

*** Revision A, Awaiting

Final Camera Selection



Complete Camera Box

Full assembly of camera box

Complete Assembly-Encloses camera

-Mounts to earth facing plate

-Holds camera at 30deg angle

-Manufacturing done as a short component



Comm Box

• Use already designed and

tested box• Mounting plate allows

connection to Satellite isogrid.• Constructed of Al6061

and anodized• TNC?



Environmental Analysis



The Harsh Environment

• Protection Against: – Atomic Oxygen (AO)– High Energy Protons and

Electrons– Debris and Micrometeors– Radiation

• The Toughest Opponent at ISS orbit



Atomic Oxygen

• Increases with the angle of incidence with Earth• Decays material in direct contact

– The rate of decay is negligible– AO is only a design factor to account for when the mission

duration is over a couple years



High Energy Protons and Electrons

• Only affects the outer region of the satellite

• A thin layer of material stops the damage

• The inflicted amount of decay is negligible over the 6 month mission



Debris and Micrometeors• Material travels at high velocity• The impacts are on the scale of a few centimeters• These impacts would not infringe upon the satellites

operation



Radiation Factors

• Solar Activity Cycle• Trapped Protons• Galactic Cosmic

Radiation• Solar Flare Protons• Solar Flare Heavy

Ions• Inner Zone Electrons



Solar Activity Cycle

• The Sun has a 22 year cycle• The cycle was at the 50 year Mauder Minimum in the year

2000• The mission will be launched in 2005• The Solar Cycle reaches a minimum in 2006

• The Sunspot Cycle will be low



Unimportant Factors

• Solar Flare Protons • Solar Flare Heavy

Ions– Only occur during

Solar Maximum



ISS orbit Protection

• Inner Zone Electrons • Trapped Protons

– Not a design factor • Altitude of mission

is much lower than where these two factors cause damage



Galactic Cosmic Radiation

• High velocities strip the atoms of their nucleus• Varies with the solar cycle• At a maximum during the Solar Minimum

– At a maximum during the missions duration



Galactic Cosmic Radiation

• Not a factor due to the low ISS orbit of 4000km

• Mainly attacks DNA– Very harmful to

manned missions



Recommendations

• To stop radiation

– Use the .25 in thick aluminum

• To guard against Micrometeors, AO, Debris, high and low temperatures and High Energy Protons and Electrons

• Use the MLI blanket



Conclusion

• The damaging effects of the environment are suppressed with the MLI blanket

• The Radiation is suppressed by the aluminum wall

• The satellite will function properly



Early Testing

• FEA– Based on CAPE requirements– Guidance provided in UN-SPEC-12311, Stress Analysis Guidelines.

• Envelope Verification• Mass Properties• Center of Gravity• Design checks and manufacturing checks• Check fits of every component as it is manufactured and returned

from outsourced processing • Pre mechanical Integration testing of all components• Electrical grounding path

– Late in assembly.– Perform after anodizing, but before components are integrated – If it is not right what should we do?

• Structural tests.



Testing Plans



Assembly Procedure

• Design Check with Designer, Maker, Team Lead and Systems

• Manufacture part• Tap all holes (Do Not Helecoil)• Check fit with hardware and structure• Part Check with Designer, Maker and Team Lead• Clean with Alcohol• Coat / Anodize

– Approve with Team Lead – All Taps plugged – Check part upon return

• Helecoil• Check Fit



Parts List

Outsourced Estimated• Fasteners: 2000 @ $.75 =

$1500• Anodizing: $500 • 6 Side panels. 9 x 12.5 x .25in

Al6061 plates:

$67 NIST• 1 Nadir Plates. 17.5 x 17

x .75in Al6061 plates:

$100 NIST• Aluminum for all casings,

boxes, ect (Look at budget for constraints)

In House• Entire structure, boxes,

mechanical interfaces and structural ground support



Budgeted

Component QuantityUnit Price

Total Price

Side Panels 15 $18.57 $278.55

Bulkheads 4 $130.00 $520.00

Boxes 30 $80.00 $2,400.00

Fastners 2000 $0.75 $1,500.00

Anodizing 1 $500.00 $500.00

Total: $5,198.55



Issues and Concerns (Things to be done)

• To get to CDR– Complete FEA

• How is the composite top panel going to effect things?

– Boxes• Design

– Need more concrete info, maybe I should have a 1 on 1 meeting with each team

• Position– Design decisions on placement to ensure box design

corresponds

– Documentation– What kind of testing should be done?


Mechanical Ground Support Equipment

The support for assembly.



Purpose

• Assist assembly of satellite.

• Allow easy integration of hardware, wiring, mechanisms, side panels.

• Allow easy transportation.• Allow easy accessibility.



Requirements

• Must be able to move through doors.

• Must allow side panels to lay out in a “flower” pattern-easy accessibility.

• Must allow rotation about one axis of at least 45 degrees.

• Must not endanger the integrity of the satellite or any of its components at any time.



Requirements Met:

• Axis enables 57 degree rotation in every direction.

• Satellite or base will each have at least five screw points and will stay attached during rotation.

• MGSE allows “flowering” of side panels.



MGSE Measurements



Parts List & Pricing



Issues and Concerns:

• Cost• Stability

dino peer review 13 november 2015 mechanisms shilling, tim martinez, michael

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