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NASA Challenge: Ultralight Starshade Structural Design

NASA is seeking to challenge the GrabCAD Community to design an ultralightstarshade structure to support the proposed NASA Advanced Innovative Concepts (NIAC) study called the Hybrid Observatory for Earth-like Exoplanets (HOEE). The HOEE study team seeks ultralightweight structural concepts for a starshade that could help determine if there is life on planets around other stars.

Observing reflected light from Earth-like planets orbiting Sun-like stars is a top priority for astronomers and for NASA. An orbiting starshade (170,000 km away) could cast a shadow of the central star without blocking the reflected light from its planets. So that it can be used with the largest ground-based telescopes, the starshade needs to be 100 m in diameter. This large structure must be tightly packaged so that it can fit inside the fairing of a large rocket (e.g., Falcon Heavy or Starship). It must also have the lowest possible mass so that chemical thrusters can keep it aligned during observations and solar electric propulsion system can change its orbit to observe many targets. NASA seeks breakthrough mechanical/structural concepts for a deployable, low mass, high stability, and high stiffness starshade structure.

Technical Background
Starshades can cast deep shadows of the target star if they are properly shaped to manage diffraction. The optimal shape has a central dark region surrounded by tapered petals. Originally it was thought that only telescope/starshade combinations in outer space could achieve adequate performance. But with the 30 m class telescopes (GMT, TMT, and ELT) currently under construction on Earth and high-performance single conjugate adaptive optics (SCAO) at visible wavelengths, it will be feasible to make these observations from the ground. These large telescopes enable the Hybrid Observatory concept, with a starshade orbiting in space and a telescope on the ground. The starshade must maneuver to be precisely on the line from target star to the telescope, matching both position and velocity, and must accelerate to stay on this line as the Earth (and observatory)rotates,. If such a system could be built, it could image a solar system in 1 minute at a distance of 5 parsecs and obtain planetary spectra with oxygen and water in 1 hour. A spectrum like the Earth’s would provide a strong indication that life is present on the planet being observed. Such a hybrid observatory could have an observing speed 1000x greater than a 6 m space telescope, as well as produce images with 6x better angular resolution. The orbit choice is a solved problem: a high ellipse with an apogee of at least 170,000 km, so the starshade can match velocity with the observatory as the Earth rotates.

The complete starshade is a spacecraft with all the systems a typical spacecraft requires. A key challenge for a cost-effective starshade system is caused by the rocket equation which governs two things: how long the starshade spacecraft can match the acceleration of the observatory and how many times its orbit can be adjusted to enable observations of different target stars. The first is managed with chemical propulsion. The second is managed with high Isp (specific impulse) solar electric propulsion. In both cases the scientific yield is roughly proportional to the achievable velocity changes. The upshot is that a low starshade structural mass is critical for a cost-effective mission. NASA hopes that the GrabCAD community can help develop innovative structural concepts to reduce the overall mass of the starshade structure.

Starshade designs were developed at JPL for space-based telescopes like the Nancy Grace Roman Space Telescope and the proposed HabEx mission. Details on the design can be found on the websites listed later in the challenge description.

NASA

There is little doubt that the 50 m diameter starshade required for a space telescope could be built and launched for a 6 m class space telescope. However, extrapolating the current 50 m diameter starshade design to a 100 m scale for use with a 30 m ground telescope showed that the mass and volume were too high for even a Falcon Heavy rocket if adequate propellant for maneuvering was added. We therefore seek alternate concepts. Such concepts include radical light weighting of the JPL concept; a deployable umbrella with petals; a rigidizable inflatable structure; and an ultralight truss, perhaps assembled in space by robots or astronauts. We are inspired by the Eiffel Tower, which is a third-order hierarchical structure, in which truss elements are themselves trusses, etc. Much work has been done on in-space assembly as well, and indeed there is a new National Strategy for it that could lead to implementation.

The goal of this challenge is to develop an innovative low-mass starshade structure that could meet the mass, shape, strength, and stiffness requirements. Solvers can consider one of these categories or a hybrid design.
1. Ultralight version of the current JPL HabEx concept
2. Umbrella with petals
3. Rigidizable inflated structure
4. Truss-based structures

In addition to being very lightweight, the ideal starshade design should be self-deployable (although we are interested in other options), and allow for compact packaging. NASA is looking for innovative packaging and deployment methods that can reliably deploy the starshade system after being placed in Earth orbit. We seek ideas to complement our studies currently in progress, hence the challenge. Our highest priority is lower mass.

Below are example designs from the HabEx final report

NASA

NASA

Requirements
Key physical requirements are:
1. The starshade structural mass including opaque membranes shall be less than 1000 kg. (Since the estimated mission cost is roughly proportional to this mass.) This mass target does not include the central hub, spacecraft bus, propulsion system, solar arrays, and power supply.

2. The starshade casts a shadow of the star based on the shape of a flat surface. In order to detect light from extrasolar planets, it is critical that reflected sunlight does not saturate the detectors. Reinforcing structures may project above or below this flat surface, with some restrictions. In use, the starshade plane may be tilted up to 30 degrees from being perpendicular to the line of sight to the telescope. The line perpendicular to the starshade plane may also be oriented at angles from the Sun ranging from 40 to 80 degrees, so the Sun is only 10 degrees above the starshade plane. In all these cases, during observations, no sunlight may strike any part that is visible to the telescope, except the sharp edges. (This is to ensure the widest range of useful angles between the Sun and the target star.). See the illustrative figure below. To construct the excluded volume above the starshade, construct a cone with a vertex on the boundary, open upwards, and half-angle of 30 degrees, and move it around the boundary of the starshade. To construct the excluded volume below the starshade, do the same but open downwards, with a vertex half angle of 80 degrees.

3. To minimize sunlight scattered towards the telescope, the starshade petal edges must be sharp, thinner than paper. Therefore the packaging and deployment or assembly process must protect all parts from damage.

4. When fully deployed, the starshade shall withstand accelerations of 0.03 g’s in the axial (out of plane) and lateral (in plane) directions. Starshade must recover its zero-g shape within tolerances within 10 seconds or less. This is to match the observatory acceleration of up to 0.003 g, using pulses from the rocket. The rocket thrust to maintain alignment during observation will be pulsed with a roughly 1-minute period and a duty cycle <10%, because the jets themselves are bright enough to interfere with observations. Hence, rapid recovery from transient acceleration is required. Note that this requirement also implies that the starshade could be constructed or assembled in low Earth orbit if desired, and could withstand the force of a small booster to reach the high orbit needed for observations.

5. The deployed starshade shall accommodate an empty cylinder 2 m in diameter in the center, open on both ends (This is reserved for the spacecraft bus and propellant tanks.) The rocket jets should be assumed to be on both ends of this tube and oriented to avoid direct impingement on the starshade itself. Normally they will be fired in balanced pairs to avoid undesired torques, but they can also be used to produce any necessary torques to re-orient the starshade. Protecting the starshade material from the jets is outside the scope of this study. See graphic below.

6. The starshade structure shall support a mission duration of 3 years (prime mission) with a preferred goal of 4 x 3 years with 3 refueling visits. This requirement means that an inflatable system must be rigidized or have a very
good leak control, given the expected number of micrometeoroid impacts based on statistical analysis.

7. The starshade shall have a central disk of 25 m radius

8. The starshade shall have at least 24 petals, each being 25 m long. (See basic HabEx design.)

9. In zero gravity during observations, the starshade shall have an edge shape tolerance of 5 mm with petal position tolerance / in plane deflection of 5 cm (This is looser than for smaller telescopes and smaller starshades.) Petals are
allowed to move out of plane by 1 meter as long as the shadow has the right shape within tolerances, and the sun does not illuminate parts seen by the telescope.

10. The packaged starshade (including central cylinder) should fit into a cylindrical package that is 14 m long by 4.5 m in diameter. (This is approximate and is based on the extended fairing static envelope specified in figure 12-10 of the Falcon Payload Users Guide. If targeting a different Launch Vehicle or performing in-space assembly, provide your assumptions.)

11. When in a packaged configuration, the Starshade must be capable of surviving launch loads. (High levels of vibration/acoustics could damage some brittle materials.)

12. Analysis:
a. Performing Structural analysis as part of your design process using hand calculations is highly recommended.  Show Free Body diagram with forces involved and use formulas from Roark & Young, Timoshenko, Shigley, and other structural analysis references to show how you solve for loads, stiffness, buckling, stresses and fundamental frequencies of the components of your Starshade concept as needed, to show compliance with the requirements.  A full Finite Element Model exceeds the scope of this competition and is not required, but if you
have the time and want you may create one.    
b.  International system of units (kg, m, sec, K) shall be used in analysis calculations.  Angles shall be reported in degrees.  
c. The following coordinate system shall be used when performing analysis and calculations

NASA

d. Use Load factors of 0.03 in the X, Y (lateral) and Z axial directions (corresponding to the 0.03 g’s axial and lateral acceleration case).
e. Minimum deployed frequency/stiffness:  design the Starshade with axial, lateral, bending, and torsional stiffnesses such that during observations, the maximum in-plane petal deflection is +/- 5 cm and the maximum allowed out-of-plane petal deflection is +/- 1 m.   After any disturbances, Starshade shall recover its zero-g shape within tolerances in 10 seconds or less.
f. Factors of safety of 1.25 (yield) and 1.4 (ultimate) for metallic structures and 1.4 (ultimate) for composite/bonded structures shall be applied to the limit loads to determine the yield and ultimate design loads and show positive margins of safety on strength.

Example: 
1. Axial limit load factor nz = 0.03
2. Limit load (axial) = 1000 kg * 0.03g’s = 294.2 N
3. Design ultimate Load (axial) = 1.4* 294.2 = 411.9 N
4. Margin of Safety on ultimate axial loads= Allowable Load
(or stress) / Design Load (or stress)  - 1   > 0  to satisfy
design criteria.

g. For kinematic deployments consider showing your kinematic analysis as well as forces involved during the deployment.

It is recognized that there are many more requirements for a flight system, such as shape accuracy for the shadow, thermal stability, opacity of the starshade after micrometeoroid impacts, and sun glints from the edges. Here we concentrate primarily on the mechanical concept and emphasize its mass.

A successful outcome of this contest will include 3D models and graphics, and/or animations of an ultra-lightweight starshade structure. These may be used to communicate the different concepts in the NIAC study report and may be considered for further development in future studies. It is understood that meeting all requirements at once is very challenging and partial success is still valuable.

Starshade design challenge submissions must include:
1. CAD models of a deployed starshade structure (Submissions to be provided in STEP or IGES file formats).
2. Proof that the Sun does not illuminate structures visible to the telescope, except for the sharp edges.
3. Include a concept for packaging the starshade system that shows a feasible method of deployment from a packaged state. This may be provided in 2D drawings or as 3D animations.
4. Provide an estimate of the starshade structural subsystem mass and packaged (stowed)/deployed dimensions.
5. Discussion of why and how the concept meets the stiffness and strength requirements. A structural analysis based on the CAD design will be very valuable. Any supplemental documents such as structural analysis shall be in PDF format.

Concept submissions should discuss scaling laws that describe the mass, stiffness, and strength as a function of major design parameters and choice of materials. In
particular, what materials or design changes should be used in a smaller-scale (1, 3, 10, or 30 m) physical model, to emulate the performance of the 100 m system?
We want to hear your ideas! The solver should discuss the feasibility of a self- deploying system versus in-space assembly in an attached description of the concept.
For this contest, a graphic showing the HabEx starshade design has been provided as a starting point. When scaled up to a 100 m diameter, the HabEx design will not meet the mass requirements for the Hybrid mission concept so an alternate design must be considered.
Ideas that should be excluded:
1. Avoid concepts that require extensive human or robotic support for assembly and/or deployment since this would greatly increase the cost of the mission, at
least in today’s environment.
2. Avoid concepts that are extremely complex as this adversely impacts fabrication, reliability, and increases mission risk.
3. Avoid concepts that require technologies that have a very low technology readiness level since this greatly increases development risks.

Design Notes from the challenge owner:
It is common to assume that to make something stronger and stiffer, we should increase its mass. But this intuition fails when the item being strengthened is its own
mass load. We expect that ingenuity is required in suitable geometric shapes that are naturally strong and stiff, and not subject to Euler buckling. It is hoped that a winning concept will be sufficiently robust that deployment on the ground does not require perfect g-negation (gravity compensation) systems.

We note that ultralight space structures are rarely stiff enough to meet our requirements, and our structure needs substantial thickness. The lowest mode frequency of an unsupported flat bar is about f = c(T/L 2 ) where c is the speed of sound, equal to (E/ρ) 1/2 , where E is the Young’s modulus and ρ is the density. T is the thickness, and L is the length. If c = 5000 m/s (e.g. aluminum) and T is 0.3 m and L is 71 m, then f is about 0.3 Hz. We need a way to remove most of the material, while maintaining a high specific stiffness, and increase the damping, so that vibrations die out quickly. Hence, the GrabCAD challenge! Also, deformation under acceleration scales as a(m/k) where a is the acceleration, m is a mass, and k is the stiffness. A mode frequency for a mass on a spring is (1/2π)(k/m) 1/2 so the deformation under acceleration is of order a/(2π f) 2 . If a = 0.03 g, f = 0.3 Hz, then the deformation is only 8 cm. Our structure must be very stiff, more like a bridge than a solar sail. Note that 0.3 Hz is not a requirement, only an example.

One design category is an improvement of the HabEx design, which already includes concepts for packaging and deployment, and edge protection.

Re-use of existing inventions is highly desirable. Extensive work has already been done on hierarchical materials, inflatable structures, coilable booms, artificial intelligence, and genetic algorithms to remove unnecessary mass. Many studies have been done on in-space assembly and construction, but few structures have been required to tolerate significant acceleration after completion.

Similarly, the natural world has remarkable examples of ultralight structures, ranging from hollow bird and dinosaur bones, dragonfly wings, to feathers, to composite materials like wood and bamboo. Engineered ultralight systems have been developed for human-powered aircraft, for radio antennas, and for racing yacht masts. Self-erecting cranes are segmented trusses engineered for high strength and low mass.

A year in the laboratory can save a week on the Internet. ; )
For information on starshades and the hybrid mission concepts see:

 HabEx Final report: https://www.jpl.nasa.gov/habex/pdf/HabEx-Final-Report-Public-Release-LINKED-0924.pdf
 NIAC summary:
https://www.nasa.gov/directorates/spacetech/niac/2022/Hybrid_Observatory_for_Earth_like_Exoplanets/
 Starshade tutorial – Doug Lisman:
https://www.jpl.nasa.gov/habex/documents/Aug2016/Lisman-Starshade.pdf
 Starshade tutorial – Steve Warwick:
https://www.jpl.nasa.gov/habex/documents/Aug2016/Warwick-NG-design-briefing-to-HabExSTDT.pptx
 In-space assembly strategy: https://www.whitehouse.gov/wp-content/uploads/2022/04/04-2022-ISAM-National-Strategy-Final.pdf
 Falcon Users Guide: https://www.spacex.com/media/falcon-users-guide-2021-09.pdf
 ExEP web site https://exoplanets.nasa.gov/exep/starshade documents
https://exoplanets.nasa.gov/exep/technology/starshade/
 Exoplanet Strategy report https://www.nap.edu/read/25187
 SPIE JATIS special issue: https://www.spiedigitallibrary.org/journals/Journal-of-Astronomical-Telescopes-Instruments-and-Systems/volume-7/issue-02/021201/Special-Section-on-Starshades-Overview-and-Dialogue/10.1117/1.JATIS.7.2.021201.full?SSO=1
 ORCAS report on adaptive optics:
https://asd.gsfc.nasa.gov/orcas/docs/ORCAS_AS3_Study_HQ_Report_Origin_Public_Version.pdf
 Many books and papers are published on metamaterials materials. For example
this article by Roderic Lakes, at U Wisc:
http://silver.neep.wisc.edu/~lakes/home.html, and his book “Composites and Metamaterials, July (2020)”.
https://ui.adsabs.harvard.edu/ is an interface to articles relevant to astrophysics and includes SPIE journals.

Eligibility
In order to be eligible for a prize, solutions must originate from either the U.S. or a designated country (see definition of designated country at https://www.acquisition.gov/far/part-25#FAR_25_003), OR have been substantially transformed in the US or designated country prior to delivery pursuant to FAR 25.403(c).

Intellectual Property
The Government is seeking a full government purpose usage license for further development of a starshade design to support the HOEE mission concept. It is hoped that the winning concepts can be included in the HOEE study presentation at the NIAC Symposium, September 20-22, 2022. The symposium will be livestreamed HERE

Requirements

  • Judging Factors

    1. Low mass with high structural stiffness as specified in the requirements
    2. Meets physical constraints on reflected sunlight
    3. Feasibility of deploying from a packaged state
    4. Feasibility of packaging inside a launch vehicle
    5. Feasibility of manufacturing and fabrication
    6. Quality and fidelity of the 3D models
    7. Validity and soundness of structural analysis

  • Requirements needed for Submission

    1. Model File Formats shall be delivered in STEP or IGES.
    2. Renderings: Two separate viewing angles and a packaged/Pre-deployed view (.jpg or .png formats)
    3. Any supplemental description and structural analysis documents shall be in PDF format
    4. If zipped, the file compression shall be compatible with Windows 10 and not require any special software to unzip.

Rules

  • ENTERING THE COMPETITION:


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    By entering the Challenge you:

      1) Accept the official GrabCAD Challenges Terms & Conditions.
      2) Agree to be bound by the decisions of the judges (Jury).
      3) Warrant that you are eligible to participate.
      4) Warrant that the submission is your original work. Warrant, to the best of your knowledge, your work is not, and has not been in production or otherwise previously published or exhibited.
      5) Warrant neither the work nor its use infringes the intellectual property rights (whether a patent, utility model, functional design right, aesthetic design right, trademark, copyright or any other intellectual property right) of any other person.
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  • Submitting an Entry


    Only entries uploaded to GrabCAD through the "Submit entry" button on this Challenge page will be considered an entry. Only public entries are eligible. We encourage teams to use GrabCAD Workbench for developing their entries. Entries are automatically given the tag "NASAULTRALIGHTSHADE"; when uploading to GrabCAD. Please do not edit or delete this tag. Only entries with valid tag will participate in the Challenge.

  • AWARDING THE WINNERS

    The sum of the Awards is the total gross amount of the reward. The awarded participant is solely liable for the payment of all taxes, duties, and other similar measures if imposed on the reward pursuant to the legislation of the country of his/her residence, domicile, citizenship, workplace, or any other criterion of similar nature. Only 1 award per person. Prizes may not be transferred or exchanged. All winners will be contacted by the GrabCAD staff to get their contact information and any other information needed to get the prize to them. Payment of cash awards is made through Checks mailed to the Winners. All team awards will be transferred to the member who entered the Challenge. Vouchers will be provided in the form of Stratasys Direct Manufacturing promo codes.

    We will release the finalists before the announcement of the winners to give the Community an opportunity to share their favorites in the comments, discuss concerns, and allow time for any testing or analysis by the Jury. The Jury will take the feedback into consideration when picking the winners.

    Winning designs will be chosen based on the Rules and Requirements schedule.

  • In order to be eligible for a prize solutions must originate from either the U.S. or a designated country (see definition of designated country at https://www.acquisition.gov/far/part-25#FAR_25_003), OR have been substantially transformed in the US or designated country prior to delivery pursuant to FAR 25.403(c).

  • Schedule

    This Challenge ends on August 22, 2022 (23:59 EST.) Finalists will be announced on August 29th, 2022 and Winners will be announced on September 5th, 2022

Prizes

$7000 in Total Prizes

$7000 in Total Prizes

First Place

$3000

Second Place

$2000

Third Place

$1000

Fourth Place

$750

Fifth Place

$250

About NASA Advanced Innovative Concepts

This contest supports the NASA Advanced Innovative Concepts (NIAC) study for a Hybrid Observatory for Earth-Like Exoplanets (HOEE). This study is sponsored by the
NASA’s Prizes, Challenges, and Crowdsourcing Program and was selected through the competitive Crowdsourcing Contenders Call for challenge ideas. The study will help inform NASA on the feasibility of the Hybrid Observatory for Earth-like Exoplanets mission concept and will be considered along with the HOEE team conceptual studies.

24 comments

  • Konstantin Kostsov

    Konstantin Kostsov about 1 month ago

    I have a couple of questions.
    1. Is the shield enough to unfold once and is it not supposed to be folded again?
    2. For what part of the shield is it supposed to be attached to the equipment? Does it have to be a tube from the center or is it possible to attach to the edge?
    3. About the petals poorly understood. Should they be necessarily required?

    Konstantin Kostsov has uploaded 21 CAD models & has left 23 comments.
  • TD ZEROFIVE

    TD ZEROFIVE about 1 month ago

    According to this document : https://www.nasa.gov/sites/default/files/atoms/files/designated_country_list_8-16-2019_tagged_0.pdf

    This NASA list of “Designated Countries” is a compilation of countries with which the United States:
    I) Has no diplomatic relations.
    II) Countries determined by the Department of State to be “State Sponsors
    of Terrorism” or identified by the Department of Commerce as “Terrorist
    Supporting Countries,”
    III) Countries under Sanction or Embargo by the United States.
    IV) Countries of Missile Technology Concern.

    I have a few questions.

    1. Why change the definition now?

    2. Why is the rule only implemented here? Why do the nasa challenges
    hosted on other platforms have no mention of it?

    https://www.nasa.gov/science-action-comic-strip-contest
    https://www.nasa.gov/solve/break_the_ice_lunar_challenge_phase_2
    https://www.nasa.gov/marsxr-challenge

    3. If you really don't want people from non-designated country to engage
    with grabcad.why not block access of your website in these country?

    TD ZEROFIVE has uploaded 0 CAD models & has left 1 comments.
  • Lucas Martin Dublanc

    Lucas Martin Dublanc 28 days ago

    Can people from Argentin participate?

    Lucas Martin Dublanc has uploaded 4 CAD models & has left 195 comments.
  • fabio pedrosa

    fabio pedrosa 26 days ago

    Portugal can participate?

    fabio pedrosa has uploaded 0 CAD models & has left 1 comments.
  • estinamir

    estinamir 26 days ago

    Can graphene enhanced clothing material be used? Such as this extra durable t-shirt? It has to be the size of the football field but can be compressed into tight container since graphene layer is thin but has memory. It should expand automatically in space when released, with little wrinkling. Expensive but lightweight, which works given price is not a factor.
    https://www.amazon.com/MK-MTKISS-Athletic-Lightweight-Polyester/dp/B093L88KQG

    estinamir has uploaded 0 CAD models & has left 4 comments.
  • estinamir

    estinamir 26 days ago

    Many international challenges on herox.com, new ones constantly added https://www.herox.com/a2agrophotovoltaics/register

    estinamir has uploaded 0 CAD models & has left 4 comments.
  • Plural Defense, Inc.

    Plural Defense, Inc. 25 days ago

    NASA seeks a structural mechanical solution, are other solutions acceptable? A gaseous particulate that creates timed windows of observation prior to critical dissipation would reduce costs and create a potentially better, longer lasting and renewable solution. A mechanical structure of the kind specified, with paper thin ribbing, is likely to be prohibitively delicate and beyond the scope of current manufacturing processes.

    Plural Defense, Inc. has uploaded 2 CAD models & has left 9 comments.
  • Sam Saifi

    Sam Saifi 24 days ago

    Make a layer of crystal and diamond, I will not tell anything further

    Sam Saifi has uploaded 0 CAD models & has left 1 comments.
  • Himanshu Deshbhratar

    Himanshu Deshbhratar 23 days ago

    Install a sonar machine and make a 360 degree scope that can see behind our planet

    Himanshu Deshbhratar has uploaded 0 CAD models & has left 1 comments.
  • Razaul Shoaib

    Razaul Shoaib 23 days ago

    Can people from india participate?

    Razaul Shoaib has uploaded 0 CAD models & has left 1 comments.
  • Sumit Kumar

    Sumit Kumar 23 days ago

    I have a suggestion; if you set a largest mirror in this progect then possibly we can see other planets and it's things clearly. And second mirror set on space where our stronots teen. Thanku

    Sumit Kumar has uploaded 0 CAD models & has left 1 comments.
  • RAJU PAL

    RAJU PAL 23 days ago

    I have Best suggestion:- Please dont wast your money to SEARCH life in other planets. There is no life in other planet. We can survive only in Earth. if you want to know universal, first you Know Earth. Earth will disclose all secret of universal. Thanks, 🕉

    RAJU PAL has uploaded 0 CAD models & has left 1 comments.
  • Bagoes Prawira N

    Bagoes Prawira N 21 days ago

    Bagoes Prawira N has uploaded 39 CAD models & has left 20 comments.
  • AN 816

    AN 816 21 days ago

    Copying the previous comment : " If you really don't want people from non-designated country to engage with grabcad. why not block access of your website in these country? "

    AN 816 has uploaded 0 CAD models & has left 1 comments.
  • estinamir

    estinamir 17 days ago

    For petals, you could probably use existing Webb sun shield design, it seems the right size and composition. You could lunch multiple petals at a time, linked up in a straight line like decorations on wire, later forming a circle. Closing petals is like closing iris on the camera to block light. https://webb.nasa.gov/content/observatory/sunshield.html

    estinamir has uploaded 0 CAD models & has left 4 comments.
  • mohammed  alfaz

    mohammed alfaz 16 days ago

    In this eligibility list for award ,Does India or United Arab Emirates are there or not ?

    mohammed alfaz has uploaded 1 CAD models & has left 1 comments.
  • Woodayan David

    Woodayan David 12 days ago

    I am from South Sudan. Can I be able submit my work?

    Woodayan David has uploaded 0 CAD models & has left 1 comments.
  • Ravi Kumar

    Ravi Kumar 9 days ago

    Folks, someone said NASA is wasting time in searching for life beyond earth. Let me tell you, NASA is visionary and there is nothing called waste. If our scientists would have thought in this way, we would not have invented rocket technology and would not have put our satellites in space. In fact, we would not have been communicating in the way we are doing today. So nothing is wasted.
    But sometimes I feel that we may not be able to identify life beyond earth not because of our efforts but because of 'Time Lapse' theory.
    I have mentioned some theories in my sci-fi books listed on Amazon.
    BALA The Immortal Indian Scientist
    BALA The Mystery of Naga Shankara

    Ravi Kumar has uploaded 0 CAD models & has left 1 comments.
  • Anh Nguyen

    Anh Nguyen 6 days ago

    It should take time, let wait.

    Anh Nguyen has uploaded 1 CAD models & has left 3 comments.
  • US D

    US D 3 days ago

    The challenge is likes "using 7000 USD reward to invest and take 1 million profit USD in 30 days". Only 24 x 25m long petals with minimum reinforce has already more than 1 ton mass.

    US D has uploaded 0 CAD models & has left 1 comments.
  • Anh Nguyen

    Anh Nguyen 2 days ago

    Finally, I completed the ~700KG design, has a lot of mass margin, now making the report, will upload soon.

    Anh Nguyen has uploaded 1 CAD models & has left 3 comments.
  • estinamir

    estinamir 2 days ago

    I think deploying via Space Shuttle would be good because of robotic arm and ability to manure around like when they repaired Hubble telescope. Chinese have one now. We may need to wait for StarShip to deploy it and may be unfold by 20 astronauts 1 per petal.

    estinamir has uploaded 0 CAD models & has left 4 comments.
  • TD ZEROONE

    TD ZEROONE about 22 hours ago

    As in the previous challenge(https://grabcad.com/challenges/nasa-challenge-new-transonic-wind-tunnel-test-section),the eligibility is updated from:

    "In order to be eligible for a prize solutions must originate from either the U.S. or a designated country (see definition of designated country at https://www.acquisition.gov/far/part-25#FAR_25_003), OR have been substantially transformed in the US or designated country prior to delivery pursuant to FAR 25.403(c)."

    To

    "“Submissions from countries listed as Type 2 and Type 3 on the NASA Designated Countries List (https://www.nasa.gov/sites/default/files/atoms/files/designated_country_list_8-16-2019_tagged_0.pdf) are not eligible for monetary awards."

    Is it possible to apply the same definition here?

    TD ZEROONE has uploaded 0 CAD models & has left 1 comments.
  • Anh Nguyen

    Anh Nguyen about 17 hours ago

    I am Vietnamese but also currently is Japan resident.

    Anh Nguyen has uploaded 1 CAD models & has left 3 comments.
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