https://www.perplexity.ai/search/hi-perplexity-i-wanted-to-do-a-Bqu90Td.Rji.... <img src="https://r2cdn.perplexity.ai/pplx-full-logo-primary-dark%402x.png" style="height:64px;margin-right:32px"/> # hi perplexity .... i wanted to do a task but i need a self photo and no camera so i guess that task is later ... maybe spam with you a bit ... ummmmmmmmmm we had started an idea of a huge autodeployable solar absorber to make solar cars workable so long as there is space for a giant reflector (and mostly if they are parked to make the idea/project/design/prototype space easier) one of the ideas is to use a lightweight reflector rather than many solar panels. i don't always remember why to do this but tend to settle on it. for example, it is much easier to start prototyping with only 1 panel, can be made more compact for cheaper possibly -- but mostly if i buy a parking lot full of panels and then abandon the project i have too many panels to handle. but one cooled panel is still useful. i was trying to figure out how to do the deployableness and one of the suggestions was to unroll mylar in modules. an idea to make it work was to use sticks and guylines, the sticks could unfold and the guylines could hold the reflective material in the right shape. but basically we want it dirt cheap, compacts to a reasonable roof size, and unfolds large enough to charge a vehicle. sound reasonable? i was thinking of seeing if we could sort out a more specific design for the modules. it would be cool to make it specific enough that i would know how to actually make a couple modules and attach them to a panel. and it doesn't have to be modules that was just one idea an ai had. Yes, it sounds reasonable, and it’s very compatible with the stuff we already scoped (cheap optics, tiny receiver, big but featherweight “sail”).[^1_1] ## Why “one cooled panel + big reflector” still makes sense - You only need to baby one **receiver**: thermal management, wiring, MPPT, etc. stay concentrated in one spot instead of spread over a parking-lot.[^1_2] - Mylar or metallized film is absurdly cheap per square meter versus PV, so growing “collector size” is mostly geometry, poles, and string.[^1_1] - Our earlier back-of-envelope said ~2.4 m² of reflector is enough for ~10 kWh/day neighborhood if you accept moderate concentration and tracking; scaling that up for a car isn’t crazy at all.[^1_1] ## Concrete module concept Let’s pick one concrete geometry you could actually build: a “ribbed wing” that unrolls mylar between fold-out tent-pole ribs, tensioned by guylines. - Base: a single rigid rectangle (say 1 m by 0.4 m) that bolts to the PV panel’s frame or to a little “spine” rail next to it.[^1_1] - Ribs: four or five collapsible tent poles (shock-corded) that hinge at the base and swing out like fingers on a hand to form a shallow trough, maybe 1 m long each.[^1_3] - Skin: one strip of mylar pre-taped to the ribs’ outer edges so that when ribs swing out and guylines pull, the film naturally forms a smooth, slightly curved surface.[^1_4] In stow: - Ribs fold flat along the base (like a folding fan). - Mylar rolls or pleats between them; guylines coil on cleats. - The whole module is maybe snowboard-sized and a few inches thick, so you can lash several around the main panel. ## Sticks + guylines details We can steal everything from tarp/tent systems. - Use fiberglass or aluminum tent poles: cheap, pack small, pre-curved if you want a quasi-parabola instead of flat.[^1_3] - Guy material: 1.5–2.5 mm Dyneema or similar, because it stretches very little but is crazy strong; you can run it pre-cut so each rib locks to a fixed angle automatically.[^1_5][^1_6] - Tensioners: sliding aluminum line tensioners instead of knots, so setup is “pull and lock” per rib, not “tie 6 fiddly hitches.”[^1_7][^1_8] One practical pattern you can build: - Each rib has a tip eyelet. - One guyline goes from tip down to a stake or to a lower edge of the base, cut so that at full tension the rib is at your desired angle (e.g., 40°). - A second, shorter line or webbing strap between adjacent ribs sets spacing and controls curvature of the membrane. ## Making it actually buildable (for you-now) To get to “I can build two and bolt them to a panel” level: - Fix a size: e.g., each module is 1.2 m wide by 1.5 m deep deployed, so two modules plus the panel give ~3–4 m² of reflector around a single “hero” PV.[^1_1] - Materials you can literally buy today: - 4–6 cheap two- or three-section tent poles (or fiberglass driveway markers cut and sleeved). - One roll of metallized mylar emergency blanket to cut to width. - 20–30 m of Dyneema or decent guyline + a handful of line tensioners.[^1_5][^1_7] - Small stainless hinges and bolts to attach poles to a plywood or aluminum base. Build steps for one module: 1. Cut and hinge ribs to the base at 10–20 cm spacing. 2. Stand ribs up, temporarily mock the curve you like (eyeball your “parabola”) with tape and string. 3. Drape mylar, tape or clamp to each rib in that mocked-up shape. 4. Add final guylines cut so that when fully tensioned the ribs naturally land in that shape without your help. 5. Fold everything back down and confirm that deployment is “flip ribs, pull four cords, done.” ## How this scales and attaches - Each module is self-contained: base, ribs, film, guylines. You can clamp to roof rails or to the PV frame with U-bolts or hose clamps. - You can start with just one or two modules feeding one panel, then later build more and daisy-chain bases along the car or parking spot edge. - The same geometry is future-proof for motorization: where a guyline attaches, you can later pin in a cheap 12 V linear actuator or tiny winch to auto-tension and track.[^1_9] If you want, next pass I can sketch explicit dimensions and rib spacing (e.g., “5 ribs, 30 cm apart, curvature approximating a 1.2 m focal length”) so you could cut wood or aluminum this week and know your cut lengths. <span style="display:none">[^1_10][^1_11][^1_12][^1_13][^1_14][^1_15][^1_16][^1_17][^1_18]</span> <div align="center">⁂</div> [^1_1]: https://www.perplexity.ai/search/79373b08-9a6d-4405-9faf-c56f75a74d30 [^1_2]: https://www.perplexity.ai/search/ab6cddeb-de69-46f6-8431-82ff473917b4 [^1_3]: https://www.sixmoondesigns.com/pages/ultimate-guide-to-ultralight-shelters [^1_4]: https://www.instructables.com/Make-a-quotcompoundquot-parabolic-solar-cooker... [^1_5]: https://www.pariaoutdoorproducts.com/products/ultralight-dyneema-tarp-tent-g... [^1_6]: https://andrewskurka.com/guyline-tension-system-backpacking-tents-tarps-hamm... [^1_7]: https://www.gearaid.com/products/guyline-kit-reflective [^1_8]: https://cascadedesigns.com/products/tent-guy-lines [^1_9]: https://www.perplexity.ai/search/70c65d56-de57-4e56-a44a-cc93765aba3b [^1_10]: https://www.youtube.com/watch?v=RNZ-y1iIe7U [^1_11]: https://mountainlaureldesigns.com/product/2-7-mm-pro-guyline/ [^1_12]: https://www.youtube.com/watch?v=3L3IRUE8Y98 [^1_13]: https://newatlas.com/automotive/gosun-roofop-soilar-ev-charger/ [^1_14]: https://www.youtube.com/watch?v=r_vgdKqoODA [^1_15]: https://www.facebook.com/CyberGuyOfficial/posts/the-dartsolar-project-integr... [^1_16]: https://news.engineering.asu.edu/2025/11/self-healing-solar-in-space/ [^1_17]: https://www.facebook.com/groups/solarcookingdoityourself/posts/1015857456712... [^1_18]: https://www.facebook.com/StartupSelfieOfficial/posts/this-compact-rooftop-so... --- # i like the easy visualization of the lines of poles unfolding (first you said like fingers (vertically) then you said like a fan (horizontally) either could work) but by two modules what i'm actually thinking about is, what different ways might farther modules work that are not directly adjacent to the solar panel but only to other modules? it would be nice if the _whole setup_ could collapse together into one bundle, and automatically deploy itself with motors or tension relief or such Good, I've got strong research on all the key ideas. Let me compose a focused answer. This is a great design question — the key insight is that **farther-out modules don't need to attach to the panel, just to each other**, and a chain or matrix of hinged connections can make the whole thing collapse into one bundle and deploy in a single motion. ## The Core Structural Idea: Daisy-Chain Hinges Think of each module as a panel that folds flat against its neighbor. The whole stack is one collapsed book — hinges alternate fold direction (like an accordion/fan-fold), and tension on two outer edges unfolds every module simultaneously. The solar panel itself is just the "first page" of that book.[^2_1][^2_2] This is exactly how the **Miura-ori** fold works: one pull on a corner unfolds the entire surface, because all the crease angles are geometrically coupled. For your design it's even simpler — you don't need the internal Miura geometry, just a row or grid of rectangular modules with accordion hinges between them.[^2_3][^2_4] ## How "Remote" Modules Differ From the First One The first module (adjacent to the panel) needs to aim reflected light *at* the panel's receiver, so its angle matters a lot. Farther modules can be at progressively shallower angles — or even flat — because they're bouncing light inward toward closer modules, which re-reflect it toward the panel. This is called a **compound reflector** geometry. Each remote module is mechanically dumber but still useful.[^2_5] Practically: - Module 1 (adjacent): aimed ~40° tilt, needs guylines to hold precise angle - Module 2 (one step out): ~20–25° tilt, slightly shallower - Module 3+: nearly flat, acting more like a "scoop" that redirects grazing sunlight inward Each module only needs to attach to its neighbors via hinges — no direct connection back to the panel frame. ## Passive Self-Deploy: The Key Mechanism You can ditch motors entirely for deployment. **Tape-spring hinges** are the magic ingredient — a strip of spring steel (like a cut-from-a-tape-measure) pre-curved so that it *snaps open* to a flat deployed state and holds there rigidly, with no latch or power needed. NASA uses these on satellite solar arrays for exactly this reason.[^2_6][^2_7][^2_8] For your build this is concretely just: - Cut short strips from a cheap metal measuring tape (already a tape spring) - Rivet or bolt them across each inter-module hinge line - In stow, they're forced flexed and held by a simple pin, Velcro, or a pull-cord loop - Release the cord → every hinge snaps open in sequence, pushing each module to its set angle The angle each module lands at is determined by how you pre-set the bend in the tape spring — one strip, bent to 40°, always deploys to 40°. No tuning needed after fabrication.[^2_6] ## Making It One Bundle To get everything to collapse into one roof-rack-sized package: - All modules fold flat like an accordion, ribs nested against each other - Mylar folds between the ribs in pleats (like a bellows), so there's no loose film to tangle - Guylines are pre-attached and coiled in small cleats on each module's edge — they auto-tension as the modules snap open and pull the film taut - The solar panel sits at one end as the "anchor page"; the whole stack is lashed to a roof rail or a simple tube backbone One practical trigger mechanism: a single cord that runs through all the retaining pins like a zipper pull. Yank it → all pins release → everything snaps open. You could motorize just this one cord with a tiny winch if you want powered deploy.[^2_3] ## Module-to-Module Connection Options | Method | How it connects | Self-deploys? | Adjustable angle? | | :-- | :-- | :-- | :-- | | Tape-spring strip hinge | Riveted to rib edges | Yes, passively | Fixed at fab time | | Torsion spring + hard stop | Pinned hinge + preset stop | Yes, passively | Swappable stops | | Piano hinge + gas strut | Standard hinge + small gas spring | Yes, passively | Adjustable stop bolt | | Living hinge (thick plastic) | Molded flex zone in rib material | Yes, passively | Fixed at molding | | Rope and cam cleat | Guyline through frame rings | No (manual pull) | Any angle | The **tape spring** approach is cheapest and lightest for a first prototype — measuring tape is maybe \$3 and you already understand it. The **torsion spring + hard stop** is slightly more robust if you want to swap angles later.[^2_7][^2_6] ## A Concrete 3-Module Chain Let's say your panel is 1 m × 0.5 m: - **Module 0 (the panel):** fixed, faces the sun baseline - **Module 1 (adjacent):** 1 m × 0.8 m mylar wing, hinged to panel's long edge, tape spring sets it at 40° tilt, guylines lock the mylar flat between 5 ribs - **Module 2 (one out):** 1 m × 0.8 m, hinged to Module 1's far edge, tape spring sets 22°, same rib/mylar/guyline construction - **Module 3 (outermost):** 1 m × 0.6 m, nearly flat (10°), mostly just scooping in low-angle light Stowed, this is four flat things stacked together, roughly 1 m × 0.8 m footprint, maybe 10–15 cm thick. Deployed, you have ~1 m × 3 m of reflector area flanking your panel, all from one pull-cord release. Adding symmetrically on both sides doubles it. The next design decision worth nailing down is the **rib spacing and count per module** — that determines how much the mylar sags between ribs (more ribs = better parabolic approximation, less sag) and how heavy/complex each module gets. Five ribs at 20 cm spacing is a reasonable starting point to prototype. <span style="display:none">[^2_10][^2_11][^2_12][^2_13][^2_14][^2_15][^2_16][^2_17][^2_18][^2_19][^2_20][^2_21][^2_22][^2_23][^2_24][^2_25][^2_26][^2_27][^2_28][^2_29][^2_30][^2_31][^2_9]</span> <div align="center">⁂</div> [^2_1]: https://patents.google.com/patent/US9559232B1/en [^2_2]: https://electrek.co/2024/06/03/accordion-style-modular-solar-array-5b-maveri... [^2_3]: https://www.jpl.nasa.gov/news/solar-power-origami-style/ [^2_4]: https://www.youtube.com/watch?v=2tbUr-n_PQA [^2_5]: https://www.instructables.com/Make-a-quotcompoundquot-parabolic-solar-cooker... [^2_6]: http://www.its.caltech.edu/~sslab/PUBLICATIONS/Rigid Deployable Solar Array 2004.pdf [^2_7]: https://www.scribd.com/document/784927992/Solar-array-deployment-analysis-co... [^2_8]: https://elib.dlr.de/120793/1/183_mier.pdf [^2_9]: https://pmc.ncbi.nlm.nih.gov/articles/PMC11459150/ [^2_10]: https://www.esmats.eu/amspapers/pastpapers/pdfs/2024/gendell.pdf [^2_11]: https://www.frontiersin.org/journals/built-environment/articles/10.3389/fbui... [^2_12]: https://ntrs.nasa.gov/api/citations/20150004083/downloads/20150004083.pdf [^2_13]: https://hanspeterschaub.info/PapersPrivate/Fulton2022.pdf [^2_14]: https://pmc.ncbi.nlm.nih.gov/articles/PMC10955954/ [^2_15]: https://www.irbnet.de/daten/iconda/CIB10900.pdf [^2_16]: https://www.academia.edu/15994241/An_Active_Deployable_Tensegrity_Structure [^2_17]: https://www.mech.kth.se/thesis/2002/phd/phd_2002_gunnar_tibert.pdf [^2_18]: https://bigidea.nianet.org/wp-content/uploads/2018/03/2018-BIG-Idea-Final-Pa... [^2_19]: https://www.sciencedirect.com/science/article/abs/pii/S0141029616316741 [^2_20]: https://www.diva-portal.org/smash/get/diva2:9104/FULLTEXT01.pdf [^2_21]: https://www.frontiersin.org/journals/space-technologies/articles/10.3389/frs... [^2_22]: https://advanced.onlinelibrary.wiley.com/doi/10.1002/advs.202408617 [^2_23]: https://arc.aiaa.org/doi/abs/10.2514/6.2024-2256 [^2_24]: https://colab.ws/articles/10.1016%2Fj.ieri.2012.06.035 [^2_25]: https://patents.google.com/patent/US9450131B1/en [^2_26]: https://www.youtube.com/watch?v=l7fht0hchiM [^2_27]: https://www.thecooldown.com/green-tech/5b-solar-panel-array-puerto-rico/ [^2_28]: https://arc.aiaa.org/doi/10.2514/1.J064488 [^2_29]: https://ntrs.nasa.gov/api/citations/19950020846/downloads/19950020846.pdf [^2_30]: https://www.sciencedirect.com/science/article/abs/pii/S1270963821004363 [^2_31]: https://www.sciencefriday.com/educational-resources/tessellation-and-miura-f...