Sumitomo Electric Industries, Ltd. has successfully spearheaded the development and publication of an international standard for automotive optical harnesses, marking a significant milestone in the automotive communication sector. This achievement was part of the International Standardization of Automotive Ethernet System Integrity Project (spanning FY2020 to FY2022), a program commissioned by Japan’s Ministry of Economy, Trade and Industry (METI) under the broader initiative to acquire and promote international standards related to energy conservation. As a result of this initiative, ISO 24581:2024 (hereafter referred to as ISO 24581) was officially published on September 24, 2024.
A Paradigm Shift in Automotive Communication
The automotive industry is currently undergoing a transformative period of unprecedented scale, driven by advancements in CASE technologies (Connected, Autonomous, Shared, Electric). Additionally, the influx of new players from diverse industries has further accelerated this transformation. Among the many challenges emerging from these advancements is the need for high-capacity, reliable communication systems to support automated driving technologies. With automated vehicles relying on data transmission from high-precision sensors, communication capacity requirements are surging both inside and outside the vehicle.
Traditional electrical harnesses using copper or aluminum materials have long been the backbone of in-vehicle communication systems. However, these conventional materials are now struggling to keep pace with the rapid increases in transmission speeds demanded by advanced automotive systems. To address this issue, optical fiber harnesses are emerging as a game-changing solution, capable of achieving ultra-high-speed data communication while maintaining stability in harsh automotive environments.
The Role of ISO 24581
The newly published ISO 24581 standard specifies the general requirements and test methods for automotive optical harnesses, including components such as multimode glass optical fiber cables and optical connectors. The standard incorporates a range of rigorous test methods, including:
- Vibration tests
- Bending tests
- High/low temperature tests
These tests ensure that optical harnesses can withstand the challenging operating conditions typical of the automotive environment, maintaining stable and high-speed data communication over the vehicle’s lifecycle.
By introducing ISO 24581, the adoption of optical harnesses enables the design of next-generation automotive communication systems independent of existing communication protocols such as automotive Ethernet and image transmission systems essential for automated driving. This expanded design flexibility accelerates the development of new automotive components, streamlining innovation across the industry.
Advantages of Optical Harnesses in Vehicles
The adoption of optical harnesses introduces several key advantages over conventional electrical systems:
- Ultra-High-Speed Communication: Optical harnesses enable data transmission rates of up to 100 Gb/s, which is critical for supporting autonomous driving systems and next-generation vehicle networks.
- Extended Communication Range: With low signal loss and high noise resistance, optical harnesses can support communication over long distances, making them ideal for larger or articulated vehicles like buses and trailers.
- Lightweight and Flexible Design: Optical fibers are thinner and lighter than traditional copper cables, contributing to reduced vehicle weight and improved energy efficiency. Additionally, their flexible structure allows for easier cable routing and system construction without constraints on electronic control unit (ECU) placement.
- Reliability in Harsh Environments: Optical harnesses exhibit high resistance to environmental factors, including extreme temperatures and vibrations, ensuring consistent performance under challenging conditions.
Supporting Future CASE Societies
As vehicles become more complex and interconnected, electronic control units (ECUs) play an increasingly central role in managing various in-vehicle systems. The adoption of optical harnesses facilitates seamless communication between ECUs, even in complex networks requiring both uni-directional and bi-directional data exchanges. Coupled with switching units (SWs) that optimize network efficiency, optical harnesses enable robust and flexible communication systems essential for modern vehicles.
Sumitomo Electric’s Contribution and Vision
Sumitomo Electric Industries is a global leader in the automotive wire harness industry, with a strong legacy of innovation in both automotive technologies and information and communication infrastructure. The successful development of ISO 24581 reflects the company’s ability to leverage synergies between these two business sectors.
The standardization effort required close collaboration across Sumitomo Electric’s automotive and communications divisions, combining decades of expertise in optical fiber and cable technologies with deep industry knowledge of automotive systems. This cross-sector innovation was instrumental in achieving the robust, reliable performance specifications defined in ISO 24581.
Moving forward, Sumitomo Electric is committed to advancing the development and application of automotive optical harnesses based on the newly established ISO 24581 standard. By promoting the adoption of optical communication systems in vehicles, the company aims to contribute to the realization of next-generation mobility solutions and the broader CASE society.
The publication of ISO 24581 represents a major leap forward for the automotive industry, providing a unified international framework for the development and testing of optical harness components. With their superior speed, reliability, and flexibility, optical harnesses are poised to address the growing demands of modern vehicles, particularly as automated driving technologies continue to evolve.
Sumitomo Electric’s leadership in this initiative underscores its ongoing dedication to innovation and global standardization. By fostering the development of cutting-edge optical communication technologies, the company is helping to drive the automotive industry into a smarter, more connected future.
