Adidas Adds Automated Weaving Robot to Shoe 3D Printing Tech

The Evolution of 3D Printed Footwear

3D printing has been making significant headway in the footwear industry, with numerous brands experimenting with 3D printed orthotics and midsoles. According to SmarTech Analysis, the 3D printing in footwear market is projected to generate over $4.2 billion in annual revenues by 2025. This explosive growth reflects both consumer demand for customized performance footwear and manufacturers’ drive for more efficient production methods.

Breaking the Midsole Barrier

Initially, 3D printing in footwear focused almost exclusively on midsoles—the cushioned layer between the foot and the outsole. Companies like Carbon and Formlabs developed specialized photopolymer resins that could be 3D printed into lattice structures providing optimal energy return and support. Adidas’s Futurecraft line has been at the forefront, releasing multiple 3D printed midsole models over the past several years.

However, this focus on midsoles revealed a critical limitation: the soft uppers—the fabric portion that wraps around the foot—remained difficult to produce with 3D printing technology. Additive manufacturing (AM) is inherently better suited for hard materials rather than soft, flexible textiles. This technical constraint meant that while midsoles could be customized and optimized, the upper portion still required traditional manufacturing methods, limiting the full potential of 3D printing in footwear.

The Soft Materials Challenge

For the most part, additive manufacturing has found its way into fashion in an awkward manner, mostly via high-concept plastic pieces that would struggle to make it into consumer wares. The challenge lies in creating soft, breathable, flexible materials that can match the comfort and performance expectations of modern athletic footwear.

Several approaches have been attempted: – Thermoplastic elastomers (TPEs): These materials offer flexibility but often lack breathability and can feel rubbery against the skin – TPU mesh structures: While providing good airflow, these can be time-consuming to print and may not offer the precise control needed for performance tuning – Hybrid approaches: Combining 3D printed components with traditional textiles, though this reintroduces manual assembly steps

Adidas’s solution to this challenge represents a significant departure from these previous attempts, leveraging a different form of automation that bridges the gap between traditional manufacturing and 3D printing.

Enter the Autonomous Weaving Robot

The FUTURECRAFT.STRUNG is a proof-of-concept sneaker that represents Adidas’s most ambitious attempt to solve the upper problem. Rather than trying to 3D print soft materials, Adidas developed a custom-built weaving robot that autonomously threads color-coded yarn across a 3D-printed midsole. This approach combines the precision and customization of 3D printing with the comfort and flexibility of traditional textile manufacturing.

How the Technology Works

The STRUNG system operates on principles similar to 3D printing but uses yarn instead of filament or resin. The robot places each thread exactly where it’s designed to go, building up the upper layer by layer. What makes this approach revolutionary is the use of different yarn types for different functions:

• Red strings: These are stiffer and stronger, designed to hold the wearer’s heel in place while providing a durable toe-box and midfoot structure
• Yellow strings: These are softer and more flexible, adding comfort and mobility to the forefoot of the shoe

This color-coded system allows the robot to optimize each area of the shoe for its specific performance requirements, something that’s difficult to achieve with traditional manufacturing methods where materials are typically uniform throughout the upper.

Performance-Driven Design

One of the most significant advantages of the STRUNG approach is its ability to incorporate real performance data into the design process. The pairs made so far were designed using performance data from professional runners, allowing Adidas to optimize the upper structure based on actual biomechanical requirements rather than generalized assumptions.

The uppers were then robotically weaved so that only the necessary material was used, reducing the weight of the shoes and waste. This targeted material placement is a key advantage over traditional cut-and-sew methods, where excess material is trimmed away and discarded.

Weight Reduction Results

The impact of this precision manufacturing is immediately apparent in the numbers: the STRUNG prototype weighs 220 grams (7.7 oz), a significant drop in weight compared to the 4D Run 1.0, a shoe whose heavy 3D printed midsole contributed to its 366-gram (12.9 oz) mass. This 40% weight reduction can translate to significant performance improvements for competitive runners.

Market Positioning and Competition

Adidas aims to have the STRUNG product in the market by late 2021 or early 2022, targeted toward road runners with speeds of five meters per second—essentially competitive to elite amateur athletes. If the company is able to deliver on this timeline, it will have made important strides toward a number of important goals, namely reducing the waste and labor associated with footwear consumption.

The Competitive Landscape

Adidas may be winning the race in 3D printed footwear, potentially ramping up its Speed Factories that use Carbon’s 3D printing technology to manufacture midsoles. However, the competition is steep across the athletic footwear industry:

• New Balance: Partnered with Formlabs to launch the TRIPLECELL platform and Rebound Resin, enabling midsole customization and limited production runs
• Under Armour: Released the Architech Futurist, featuring a 3D printed midsole produced in collaboration with EOS
• Nike: Experimented with 3D printing through various initiatives including the Flyprint technology for uppers
• Voxel8: Developed a method for producing shoe uppers directly with 3D printing, though this approach has seen limited commercial adoption

Sustainability and Ethical Considerations

The push toward automated manufacturing in footwear isn’t just about performance—it’s also about addressing the significant sustainability and ethical challenges inherent in the traditional footwear industry.

Environmental Impact

With roughly 300 million pairs of shoes ending up in landfills per year, the amount of waste from the footwear industry is substantial. Traditional shoe manufacturing generates waste at multiple stages: – Material waste: Cut-and-sew methods for uppers generate significant textile scrap – Overproduction: Batch manufacturing leads to unsold inventory that may be destroyed – Transportation emissions: Global supply chains with multiple manufacturing steps – End-of-life issues: Mixed-material shoes are difficult to recycle

Adidas has made commitments to sustainability and received recognition from some environmental groups in response. The company has set ambitious goals including using only recycled polyester by 2024 and achieving climate neutrality by 2050.

Labor and Supply Chain Ethics

Adidas claims to be taking efforts to ensure the fair treatment of the workers in its supplier factories and it is considered one of the more transparent of the athletic wear manufacturers when it comes to its supply chain. The company publishes annual sustainability reports and has implemented various supplier monitoring programs.

However, significant challenges remain, particularly when it comes to ensuring a fair wage for garment producers in developing countries. Reports have documented ongoing issues with working conditions and wage levels in various supplier factories, highlighting the gap between corporate commitments and on-the-ground reality.

Automation as a Solution?

Automating the production of shoe manufacturing via 3D printing and robotic stitching could impact these issues by reducing the industry’s dependence on underpaid labor in developing countries. This shift could potentially: – Reduce labor exploitation by moving production closer to end markets with stronger labor protections – Increase transparency through automated, trackable manufacturing processes – Reduce material waste through precision manufacturing that uses only what’s needed

However, this transition also raises questions about job displacement in developing economies that currently depend on footwear manufacturing. Some argue that the solution to labor exploitation should be improved wages and working conditions rather than automation that eliminates jobs entirely. Critics note that companies like Adidas could address fair wage concerns by spending fewer funds on athlete contracts and executive compensation.

The Bigger Picture: Beyond Individual Products

While innovations like the STRUNG technology represent important steps forward, it’s essential to consider them within the broader context of consumer culture and economic systems.

Cultural and Systemic Challenges

As 3DPrint.com Executive Editor Joris Peels has pointed out in his Brittle Spear series, much of the waste associated with consumerism has become ingrained in our culture. Breaking the cycles associated with unethical consumption may require more than slow-moving initiatives from manufacturers but might also necessitate a fundamental change to our culture and consumption patterns.

What Peels doesn’t address is the fact that economic growth is also built into our existing system, which naturally drives companies to seek greater profits from the release of an unending series of products that then contribute to issues such as ecological destruction and human rights abuses. This growth imperative creates tension between genuine sustainability efforts and the business models that drive continuous product development.

The Race Within the Race

Adidas may be winning the race in 3D printed footwear technology, but as the article notes, “none of us are winning the race against the larger problems of social and economic inequality and ecological collapse.” This recognition is crucial—technological innovations, no matter how impressive, cannot solve systemic issues without broader cultural and economic changes.

The footwear industry, for all its innovation, remains part of a larger economic system that prioritizes growth and profit over ecological stability and human wellbeing. Addressing these fundamental challenges will require more than just better manufacturing technology—it will require rethinking our relationship with consumption, products, and the natural world.

Future Outlook

The development of technologies like STRUNG suggests that the footwear industry is moving toward more personalized, automated, and potentially sustainable manufacturing methods. However, the full impact of these technologies will depend on how they’re implemented within the broader context of corporate priorities, consumer behavior, and regulatory frameworks.

Key questions for the future include: – Accessibility: Will these technologies remain limited to high-end performance shoes or will they scale to mainstream products? – Cost implications: Will automated manufacturing reduce costs for consumers or primarily benefit corporate margins? – Transition strategies: How will companies and communities manage the shift away from traditional manufacturing employment? – Regulatory oversight: Will there be adequate safeguards to ensure that automation benefits workers rather than just eliminating jobs?

Frequently Asked Questions

[Image courtesy of adidas.]

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