As unmanned aerial vehicles (Uavs) evolve, every gram impacts flight time, and every signal determines flight safety. Traditional rigid PCBs cannot fit into compact, folded drone frames, while flexible PCBs alone lack structural support. UGPCB solves this challenge with the unmanned aerial vehicle rigid-flex PCB—a specialized circuit board designed for high-vibration, space-constrained aerospace applications.
This article explains the design, Materialien, and manufacturing standards behind this advanced Starrflex-Leiterplatte. You will learn why it is the preferred interconnect solution for modern drone electronics.

1. Product Overview and Definition
A UAV rigid-flex PCB combines rigid circuit board sections with flexible circuit board sections into a single, unified structure. The rigid areas (made of FR-4) support heavy components like processors and connectors. The flexible areas (made of polyimide, or PI) allow bending and folding. This design removes the need for connectors and wiring harnesses.
Dieses UGPCB, we define a high-quality rigid-flex printed circuit board as one that maintains signal integrity under drone-specific stresses, including high vibration, tight folding, and wide temperature variation. Our model is tailored for flight control systems, video transmission modules, and gimbal assemblies.
2. Key Specifications and Structure
The table below lists the core specifications for this UGPCB model.
| Parameter | Spezifikation |
|---|---|
| Modell | UAV Rigid-Flex PCB |
| Material | FR-4 (starr) + PI (flex) |
| Layer -Stackup | Starr: 4 Schichten / Flex: 2 Schichten |
| Fertige Dicke | Rigid area: 1.0mm / Flex area: 0.15mm |
| Kupferdicke | 1 oz (internal and external layers) |
| Oberflächenbeschaffung | Immersionsgold (ZUSTIMMEN) |
| Min. Verfolgen / Raum | 4 Mil / 4 Mil |
| Farbe der Lötmaske | Grün (starr) / White coverlay (flex) |
3. How It Works and Key Design Considerations
Wie es funktioniert
Das Starrflex-Leiterplatte acts as the central nervous system of a drone. The 4-layer rigid section provides a stable platform for soldering core components such as the main processor, Gyroskop, and power management ICs. The 2-layer flexible section connects moving parts—like motors and gimbal cameras—without mechanical connectors. This allows free movement and folding without breaking the electrical path.
Konstruktionsüberlegungen
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Transition Zone Protection: The junction between rigid and flexible areas is the most stress-prone point. UGPCB reinforces this area using teardrop pads and tapered trace widths. This prevents circuit breaks caused by continuous drone vibration.
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Impedanzkontrolle: For high-frequency video transmission signals (typically 50Ω or 100Ω differential), we use the 4 mil trace width and spacing to maintain consistent impedance across both rigid and flex sections.
4. Materialauswahl: FR-4 and PI
Why does UGPCB use FR-4 and PI for this unmanned aerial vehicle rigid-flex PCB?
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Strenge Bereiche (FR-4): We select high-Tg (glass transition temperature) FR-4. This ensures the board does not soften or warp during high-power drone flights, preventing solder joint failure.
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Flex Areas (PI – Polyimid): The flexible sections use high-grade polyimide. This material withstands repeated bending and extreme temperatures ranging from -40°C to +150°C. The asymmetric thickness (1.0mm rigid vs. 0.15mm flex) balances mechanical strength with the thinness required for tight folding.
5. Performance Features
The combination of 1 Oz Kupfer, Eintauchen Gold, Und 4 mil Trace/Raum delivers measurable performance benefits.
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Hohe Zuverlässigkeit: Immersionsgold (ZUSTIMMEN) creates a flat, oxidation-resistant surface. This supports fine-pitch BGA soldering and eliminates the risk of solder balls common with HASL finishes.
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Signalintegrität: Der 4 mil trace width allows designers to route differential pairs in tight spaces. This reduces electromagnetic interference (EMI), which is critical for sensitive GPS and video signals.
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Weight Reduction: Replacing a “rigid board + Stecker + cable” assembly with a single rigid-flex board can reduce total interconnect weight by up to 40%. This weight saving extends drone flight time.
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Wärmeleistung: The white coverlay on the flexible section reflects more heat than traditional yellow coverlay. This helps manage temperatures during prolonged drone hovering.
6. Industry Classification
Based on IPC and industry standards, this product falls under:
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Primary Category: Flexible and Rigid-Flex Printed Boards
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Secondary Category: Multi-layer Rigid-Flex with Asymmetric Construction
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Application Class: Aerospace and Unmanned Aerial Vehicle Electronics
7. Herstellungsprozess (IPC-6013 & UL Compliance)
UGPCB follows a controlled process to meet IPC-6013 (Flexible/Rigid-Flex Board Qualification) and UL 94 V-0 flammability standards. The key steps for this 4-layer rigid + 2-layer flex design are:
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Materialvorbereitung: FR-4 and PI base materials are cleaned and prepared.
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Coverlay and Lamination: The flexible areas receive precision coverlay openings. Der 4 rigid layers and 2 flex layers are then laminated together under high temperature and vacuum. This step requires precise adhesive flow control to prevent voids at the rigid-flex boundary.
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Bohren und Plattieren: Laser drilling is used for microvias in the flexible areas. Copper is then plated to achieve 1 oz thickness in all vias.
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Outer Layer Imaging and Plating: The outer layer circuits are formed, and final copper plating completes the 1 oz specification.
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Oberflächenbeschaffung (Immersionsgold): ENIG is applied to all exposed copper pads.
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Profiling and Electrical Test: The board is routed to final shape. Every board undergoes 100% Flying-Probe-Tests to verify electrical integrity.
8. Typische Anwendungen
Das unmanned aerial vehicle rigid-flex PCB is suitable for the following applications:
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Foldable Consumer Drones: Used in hinge areas that require thousands of folds over the product lifespan.
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FPV (First-Person View) Racing Drones: Eliminates connectors to reduce weight and improve thrust-to-weight ratio.
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Camera Gimbals: Connects motors to the main board with fine flexible circuits that ensure zero signal lag during rapid movement.
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Tethered Drones: Der 1 oz copper in rigid sections handles high current and dissipates heat effectively during long-duration operations.

9. Warum wählen Sie UGPCB??
UGPCB ist spezialisiert auf Starr-Flex-gedruckte Leiterplatten with complex stackups. We have proven experience manufacturing fine-line designs (4 mil/4 mil) and asymmetric structures (1.0mm rigid + 0.15mm flex). Our commitment includes:
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Exact Specification Match: We build strictly to your Gerber files and stackup requirements.
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Fast Prototyping: Wir bieten an 5- to 7-day expedited service for drone developers who need rapid iteration.
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Entwurfsunterstützung: Our engineering team reviews your files to optimize rigid-flex transitions and minimize manufacturing risks.
10. Fordern Sie ein Angebot an
Are you developing a drone and need a UAV rigid-flex PCB that balances weight, Haltbarkeit, und Signalintegrität? UGPCB supports projects from prototype to mass production. Contact our sales team for a competitive quote based on your 4-layer rigid, 2-layer flex requirements.
Click “Inquire Now” to let UGPCB support your next-generation drone design.
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