How Structural Electronics Is Reshaping Electrical Engineering

In the ever-evolving landscape of electrical engineering, a revolutionary approach is gaining momentum: structural electronics.

Unlike traditional electronics that are housed within protective casings, structural electronics integrate electrical functionality directly into the materials that form the structure of a device.

This paradigm shift represents a fundamental reimagining of how we design, manufacture, and implement electronic systems.

Breaking Down Traditional Boundaries

For decades, electronic design has followed a consistent pattern: electrical components are mounted on rigid circuit boards, which are then housed within a protective structure. This approach creates a clear division between the electronics that provide functionality and the structures that provide physical form and protection. Structural electronics dissolve this boundary, embedding circuits, sensors, and other electronic components directly into the structural materials themselves.

This integration enables a host of new possibilities. Devices become lighter as redundant casings are eliminated. Forms become more flexible and adaptable, freed from the constraints of accommodating separate circuit boards. And perhaps most importantly, new functionalities emerge as electronics can now be distributed throughout an entire structure rather than concentrated in specific areas.

Key Technologies Driving the Revolution

Several technological advances have converged to make structural electronics viable.

3D-MIDs (3-Dimensional Mechatronic Integrated Devices)

3D-MIDs represent one of the most promising approaches to structural electronics. These devices are essentially plastic molded substrates with traces running along any surface, including at right angles and running vertically. The manufacturing process, known as Laser Direct Structuring (LDS), uses a laser to etch the circuit pattern directly onto the surface of a 3D substrate, which then undergoes metalization treatment to build up conductive pathways.

HARTING, the industry's leading supplier of MID products, has developed innovative component carrier MID substrates that act as vertical adapters for devices with standard footprints. These carriers allow designers to vertically mount an SMD part with a standard footprint, and the carrier is soldered to the board just like any other SMD component.

Printed Electronics

Printed electronics uses conductive, resistive, and dielectric inks to create circuits directly on or within structural materials. Unlike traditional PCB manufacturing, which is a reductive process (etching away copper from a continuous sheet), printed electronics is an additive process where signal pathways are printed directly onto a substrate.

When a design requires pathways to cross over each other, a small patch of dielectric material is printed in that location, sufficiently expanded beyond the crossover to achieve the required level of isolation between different signals. This approach eliminates the need for multiple layers separated by dielectric materials, as in traditional PCBs.

Flexible and Stretchable Electronics

The development of flexible substrates and stretchable conductive inks has liberated electronics from the rigidity of traditional PCBs. These materials can bend, twist, and stretch while maintaining electrical functionality, making them ideal for integration into dynamic structural components.

Specialized materials can achieve 100-1000% elongation while maintaining conductivity, typically through geometric designs (serpentine or fractal patterns), composite materials (conductive particles in elastic matrices), or liquid metal alloys in elastomeric channels.

In-Mold Electronics (IME)

IME technology allows electronic circuits to be printed onto a flat film, which is then thermoformed and injection molded, creating a three-dimensional part with embedded electronics. This process eliminates assembly steps, reduces weight, and creates more durable products by protecting electronic components within the structure itself.

Industry Applications Transforming Engineering Practice

Structural electronics is already making significant inroads across multiple industries.

Automotive Engineering

Modern vehicles are increasingly incorporating structural electronics into their design. Touch-sensitive control surfaces are being integrated directly into dashboards and door panels, eliminating the need for separate buttons and switches. Heating elements are being embedded into structural components rather than added as separate systems. And sensors for everything from occupant detection to structural health monitoring are being built directly into the vehicle's frame and body panels.

Tesla has pioneered the integration of electronics into structural components. Their vehicles feature center console touch panels with haptic feedback created using in-mold electronics, steering column controls printed directly onto 3D surfaces, and door panels with integrated lighting, controls, and electronic functions. The result is a 30% reduction in dashboard assembly complexity, 15% weight reduction, and higher reliability due to the elimination of mechanical buttons and connections.

Aerospace and Defense

Weight reduction is a critical concern in aerospace applications, making structural electronics particularly valuable. Aircraft manufacturers are exploring ways to integrate antennas directly into wing structures, embed health monitoring systems into critical components, and create multifunctional materials that can serve both structural and electronic purposes simultaneously.

Airbus has implemented structural electronics in several aircraft systems, including lightning strike protection integrated with wing structure electronics, fuselage panels with embedded strain gauges for structural health monitoring, and embedded antenna systems that eliminate aerodynamic drag. Their A350 XWB incorporates over 1,000 sensors embedded in structural components, reducing weight by 200kg compared to conventional approaches while providing significantly enhanced monitoring capabilities.

Consumer Electronics

Perhaps the most visible application of structural electronics is in consumer devices. Through IME, TactoTek, a lead company in this domain is revolutionizing product design through innovative headphone solutions. Modern headphones utilizing structural electronics integrate components directly into curved structural elements, allowing designers to optimize physical curvature for intuitive interaction while maintaining a sleek aesthetic with transparent materials and subtle metallic finishes. These designs incorporate LED indicators embedded within the structure to communicate device status, touch-sensitive controls without separate button assemblies, and curved form factors that would be challenging to achieve using conventional manufacturing—all while reducing weight and improving durability. This approach represents a significant departure from traditional electronics, which would require separate circuit boards and mechanical assemblies, resulting in bulkier products with more potential failure points.

Medical Devices

The medical field is benefiting from structural electronics through the development of conformable diagnostic equipment, smart prosthetics with embedded sensing and actuation, and implantable devices that can better match the contours of the human body.

Ultra-thin conformal sensors that adhere directly to the skin, integrated accelerometers, ECG, and EMG in a single flexible substrate, and stretchable circuits that move naturally with the body are revolutionizing patient monitoring. Clinical studies have shown these systems provide medical-grade data quality while being significantly more comfortable for patients than traditional monitoring equipment, increasing compliance rates by over 60%.

Engineering Challenges and Solutions

While the potential of structural electronics is immense, significant engineering challenges must be addressed.

Thermal Management

When electronic components are embedded within structural materials, traditional cooling approaches like heat sinks and fans may be impossible to implement. Engineers are developing innovative solutions including phase-change materials, micro-fluidic cooling channels integrated into the structure, and thermally conductive structural materials.

Reliability and Maintenance

Traditional electronics can be repaired by replacing discrete components or entire circuit boards. Structural electronics presents challenges for maintenance and repair, as electronic functions are integrated into the structure itself. This is driving the development of self-healing materials and modular approaches that allow for targeted replacement of failed sections.

Design Methodologies

Structural electronics requires engineers to think differently about design. Rather than designing the electronics and structure separately, they must be considered as a unified system from the earliest stages. This is driving the development of new CAD tools that can simultaneously model mechanical, thermal, and electrical properties, as well as advances in multi-physics simulation.

Altium Designer: Leading the Structural Electronics Revolution

Altium Designer has positioned itself at the forefront of structural electronics design with capabilities that extend beyond traditional PCB design.

3D Electronics Design

Altium Designer's 3D PCB design capabilities allow engineers to visualize and design electronic circuits that conform to non-planar surfaces and integrate with mechanical structures. The new 3D-MID tool brings true 3D circuit design to Altium Designer for the first time, allowing you to combine electrical and mechanical functionality into a single part.

A 3D-MID document integrates into your Altium Designer project in the same way as a standard PCB - its components and connectivity are driven by your schematic design, and it incorporates standard SMT footprints from your usual component library.

MCAD-ECAD Co-Design

Native integration with mechanical CAD systems enables seamless collaboration between electrical and mechanical engineers, essential for structural electronics design. When designing the substrate in MCAD, 3D curves can be placed on the surface of the part and included in the exported IGES file. These "curves" can then be displayed in Altium Designer and used as a guide for placing components and regions, and during routing.

Printed Electronics Support

Altium Designer also supports printed electronics design, where the circuit is printed directly onto a substrate. The layer stack can be configured for printed electronics, with conductive and non-conductive layers defined according to the manufacturing process. Dielectric shapes can be manually created or automatically generated to isolate crossovers between different nets.

Manufacturing Output

Altium Designer can generate the manufacturing data required for production of structural electronics. For 3D-MIDs, the design can be exported in formats compatible with Laser Direct Structuring (LDS) machines. For printed electronics, outputs include files for each conductive printing pass and each dielectric printing pass, typically in Gerber format.

The Future of Electrical Engineering

As structural electronics continues to mature, we can expect to see a shift in how electrical engineers approach their work.

Interdisciplinary Collaboration

The line between electrical engineering and other disciplines like mechanical, materials, and chemical engineering will continue to blur. Successful implementation of structural electronics requires expertise across these domains, driving more collaborative approaches to design and development.

New Educational Paradigms

Engineering education will need to evolve to prepare students for this interdisciplinary future. Curricula that have traditionally separated electrical and mechanical engineering will need to create crossover courses that teach integrated design principles.

Evolving Standards and Practices

Industry standards and best practices will need to adapt to this new paradigm. From design validation to testing methodologies to end-of-life considerations, the structural electronics revolution will necessitate a rethinking of established norms.

Conclusion

Structural electronics represents not only a new technology, but a new philosophy in electrical engineering. By breaking down the artificial boundary between structure and function, it opens the door to designs that are more efficient, more capable, and more integrated than ever before.

As this field continues to mature, electrical engineers have an unprecedented opportunity to reimagine their role and their creations, designing truly integrated systems where every element serves both structural and electronic purposes. Tools like Altium Designer are paving the way, providing the capabilities needed to turn the promise of structural electronics into reality.

For engineers accustomed to traditional approaches, structural electronics may initially seem challenging. However, those who embrace this paradigm shift will find themselves at the forefront of a revolution that promises to reshape both electrical engineering and the very nature of the products and systems we create.

Explore how Altium Designer supports printed electronics and enables the integration of electrical circuits with three-dimensional mechanical parts.