Heliosaur — Origami Solar Sail
A folded photovoltaic solar sail that deploys from a 3U CubeSat into a 25 m² flower of thin-film cells. It both catches sunlight as power and as gentle thrust, letting tiny student spacecraft change orbit without fuel.
Snapshot
Feasibility at a glance
PT localization
6/10
Partial
Most steps can be localised in Portugal.
Per unit
€18,000–€28,000 per unit
at 8-unit volume
Starter batch
8units
minimum viable run
To first batch
20weeks
6 phases, design to ship
Budget
€144K–€314K
all-in estimate
Bottom line
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Picked based on the localization score (6/10) plus the dominant process (cnc machining). For an early build at this batch size, this gives you the best balance of cost, risk, and speed of iteration.
What it does
4 capabilities
Stores compactly inside a CubeSat slot during launch.
Unfurls in vacuum into four overlapping petals using shape-memory hinges.
Catches photons as electricity AND as gentle thrust at the same time.
Folds back on command for a controlled de-orbit when the mission ends.
How it's made
4 stations · build route
- 1
Coat the film
Vacuum-deposit GaAs photovoltaic onto rolls of aluminised mylar.
- 2
Crease the origami
CNC-cut creases, folded by hand on a temperature-controlled jig.
- 3
Wind the booms
Filament-wound carbon composite — they roll up like a tape measure.
- 4
Vacuum deploy
Final qual is a full deployment in a thermal-vacuum chamber, twice.
Coat the film
Vacuum-deposit GaAs photovoltaic onto rolls of aluminised mylar.
Crease the origami
CNC-cut creases, folded by hand on a temperature-controlled jig.
Wind the booms
Filament-wound carbon composite — they roll up like a tape measure.
Vacuum deploy
Final qual is a full deployment in a thermal-vacuum chamber, twice.
Risks to watch
3 identified · 2 blocking
Critical
Deployment mechanism fails in vacuum
Vacuum deployments are unforgiving — one stuck hinge ends the mission.
Mitigation — Vacuum-cycle the hinge mechanism 50× before sign-off; redundant release path.
High
Material delamination after thermal cycling
Bonded composite + film stacks crack at ~50 cycles unless the bond is qualified.
Mitigation — Run 100 thermal-vacuum cycles on a witness panel before flight build.
Medium
Random-vibe load shears connectors
Launcher-induced vibe finds the weakest connector, every time.
Mitigation — Stake every connector and qualify on a vibe table to 12g RMS.
Production timeline
20 weeks to first batch
CNC machining
wk 1–2Composite lay-up
wk 3Laser cutting
wk 4Filament winding
wk 5Final assembly
wk 6Functional QA & batch sign-off
wk 7CNC machining
Composite lay-up
Laser cutting
Filament winding
Final assembly
Functional QA & batch sign-off
wk 1–2 is the longest stretch — CNC machining takes 2 weeks of the 7 weeks on this build.
What goes into it
5 materials · 6 processes
Materials
Processes
Design philosophy and best practices
5 principles
An origami solar sail must fold into a small volume and open reliably in space. The thin film, booms and hinges must work after launch and stay flat in sunlight.
1
Fold to avoid tearing
Fold patterns must avoid sharp creases that crack the film coating.
2
Make deployment repeatable
Booms and hinges need ground tests in vacuum and cold to prove they open every time.
3
Manage film tension
The sail must stay flat without tearing; tension paths and rip-stop help.
4
Plan for thermal and UV effects
Sunlight heats and ages the film. Choose coatings and materials tested for space.
5
Follow space test standards
Vibration, thermal vacuum and outgassing tests (for example ECSS standards) apply to every part.
Common pitfalls
Avoid
Shape-memory hinges that behave differently in vacuum and cold.
Avoid
Booms that buckle under uneven load.
Avoid
Static charge and dust during folding.
Avoid
Underestimating how long ground testing takes.
10-year evolution forecast (2026-2036)
4 phases
Solar sails have flown on several demonstration missions. The points below are trends.
2026–2028
Small demonstrations
Trend: CubeSat-sized sails test deployment.
2028–2031
Better booms
Trend: lighter composite booms that roll up.
2031–2034
Larger sails
Trend: bigger sails for science and deorbit.
2034–2036
Deorbit uses
Trend: drag sails help remove old satellites.
Outlook
Expect solar sails to stay specialist products for demos, science and deorbit.
Materials intelligence
5 materials
Aluminised polyester film
Medium supply risk
Sail film
Sourced from: Made by a few film producers in the US, Japan and Europe.
Thin-film GaAs cells
High supply risk
Power
Sourced from: Made by a few specialist makers in Europe, the US and China.
Carbon fibre
Medium supply risk
Booms
Sourced from: Carbon fibre is made mainly in Japan, the US and China.
Dyneema fibre
Medium supply risk
Retraction lines
Sourced from: Made mainly in the Netherlands and the US.
Nickel-titanium alloy
Medium supply risk
Shape-memory hinges
Sourced from: Made by a few specialist producers in the US, Europe and Asia.
Prototyping and rapid manufacturing in Portugal
4 companies from the atlas
Taveiro
Space PCB fabrication and soldering
Control electronics for deployment.
Vila Nova de Famalicão
Laser cutting
Thin metal fittings and templates.
Marinha Grande
Laser cutting and assembly
Fold test rigs and templates.
Marinha Grande
CNC machining
Boom end fittings and hinge blocks.
567 Portuguese manufacturers matched
None cover the whole build — it splits across steps.
Shortlist
567 matched · 8 shown, ranked by coverage
Services each manufacturer can handle for this build.
Manufacturer
Location
Covers
Certifications
People
Nouvelle-Aquitaine
—
—
Registry coverage
Portuguese producers per required step
Final Assembly
369
CNC Machining
212
Testing & Inspection
178
Composite Layup
15
Laser Cutting
13
Filament Winding
2
Depth
How many cover more than one step
The gap
Picked based on the localization score (6/10) plus the dominant process (cnc machining). For an early build at this batch size, this gives you the best balance of cost, risk, and speed of iteration.
Send one RFQ to the top 4
DIB4T, Epsilon Composite, Almadesign, REROM — same package, one click.
The plan
9 tasks · 30 weeks to first batch
Week 1
2 tasks
Lock the pilot scope to one variant
One material set, one feature set, one user persona. Anything else is roadmap, not pilot.
Shortlist three vendors per critical step
Use GETMILK Match to pull a ranked list across the top three processes — cnc_machining, composite_layup, laser_cutting. Send the same RFQ to all three; do not customise per vendor yet.
Weeks 2–3
2 tasks
Freeze the design for the first 10 units
Move the active CAD set to a tagged release; any change after the freeze gets logged in the change-board.
Place first-article orders with two of the three vendors
waits on Vendor shortlist signed off
Order one of each critical part at full spec. Do not buy 100 — buy 1, inspect, learn, then buy 100.
Weeks 4–7
2 tasks
Run the integration pilot
waits on First articles delivered
Ten complete units assembled in-house. Track yield, defect modes, and cycle time on a shared dashboard.
Kick off compliance + certification
Engage a notified body for the relevant standards. Booking a slot now beats discovering a 12-week wait later.
Weeks 8–16
2 tasks
Put 25 units in the hands of lighthouse users
waits on Integration pilot complete
These users help refine the product, but they also become your first paid customers. Charge a symbolic price so the data is real.
Scale-readiness review with the chosen primary vendor
waits on Lighthouse trial telemetry
Before you tool up for 1000 units, walk the line together and agree on capacity, payment terms, and the failure-mode plan.
Ongoing
1 task
Stand up a customer support loop
Every defect that reaches a user becomes a ticket, a root cause, a fix, and a regression test on the line.
Who you need
3 roles to fill before month one
Mission qualification partner
ESA Φ-lab
Free flight-heritage advice for student-led missions.
PT aerospace prime
Tekever
Has the supply chain we want to plug into.
Vacuum / thermal test lab
CTAE
Books fastest in the EU for academic partners.
Watch-outs
3 things to avoid in this plan
cost
Founder time leaks into vendor management instead of customer development
certification
Compliance booked too late and blocks shipping for 8+ weeks
quality
Demand exceeds the chosen vendor's small-batch capacity right when momentum matters
2 tasks in week 1
Lock the pilot scope to one variant