By: Aviv Shoval, Pixel Watch Engineering Director
Jonah Becker, Pixel Watch Industrial Design Director
Repairable design is an essential part of a device’s longevity. It enables a product to be enjoyed longer and gives its first user, or a second one, more utility. We embedded this intention in the design for Pixel Watch 4. We recognized that a repair experience is also a product experience where ease of use matters and breakthrough solutions are possible.
In designing Pixel Watch 4, we discovered that repairability is indeed the ultimate complication for a smartwatch. Designing a small but easily repairable product is a challenge; but challenges lead to inspiration. The first generation Pixel Watch was widely praised, but also received a few critical reviews relating to our internal design, and we took that feedback to heart. Our teams collaborated to define a repairability “North Star,” and everyone who touched the opportunity shared a commitment to that outcome. The team didn't just write specs; they sat shoulder to shoulder, taking devices apart to understand their shortcomings and then getting to work—creating renderings and prototypes to make a high-quality repairable watch tangible. At a pivotal workshop, a conceptual render of the Pixel Watch 4 internal design was on display as a poster. Following the workshop, the engineering team took this artifact back to their workspace, pointing to it as a blueprint of the goal we were collectively pursuing.
Our teams even practiced drafting "headlines from the future," envisioning the public response we hoped for and questioning what "would have to be true" to earn that recognition. Some of the tech reviews for the Pixel Watch 4 have been remarkably close to our aspiration, a testament to the power of a shared vision and empowering those closest to the work. The partnership we created among our industrial design, engineering, operations, sourcing and sustainability teams was rewarding, and we are delighted by what we achieved for our customers. In all aspects of sustainability, we want to enable industry progress and hope that sharing some of the insights from our work here will inspire more ideas in repairable design and lead to longer and better product experiences.
Saving space for repair
Adhesives are a common choice for sealing product enclosures where thinness is a priority. However, removing adhesives and reapplying them during a repair is often tedious and imprecise. A premium product repair experience demanded a better solution. We designed a dual-gasket architecture to achieve 5ATM and IP68 dust/water ingress protection ratings, before and after a repair, without any adhesive in critical-to-repair interfaces. This approach would normally add thickness; however, we also redesigned the internal electromechanical stack, focusing on deep miniaturization to create more space.
We developed a tiny, but powerful printed circuit board (PCB) which was populated precisely to minimize the product’s profile. This PCB also utilizes "hot bar connectors" or specialized conductive joints between components to further reduce thickness. We also designed a novel linear resonant actuator (LRA), for haptic functionality that is not only 10% smaller in volume but delivers 15% more strength at the same power. The result is that Pixel Watch 4 maintains the same sleek profile as Pixel Watch 3 but delivers an even more beautiful design with its larger dome-shaped display.
A well-rounded battery
We didn’t cut corners on the battery (despite its shape) to make it easier to remove. In fact, by adopting a stacked cell battery with a custom shape, we better utilized internal space and achieved a 50% increase in volumetric energy density compared with the “traditional” roll stackup we used in previous years. This delivered more battery capacity without adding thickness. The new electromechanical architecture also enabled direct battery access without disconnecting the biosensor hub, reducing repair complexity. We went even further with the charging architecture to reclaim internal space. We moved the charging contact points from the bottom to the side of the watch in a new design featuring stronger magnets for a more intuitive connection and delivering 25% faster charging times than Pixel Watch 3. These improvements along with a new curved display reduced overall volume by 4%. All together, Pixel Watch 4 feels slimmer than its predecessor but is also a joy to disassemble on the workbench.
Precision and post-repair quality
The shift from adhesive to robust gasket seals presented a major design challenge in creating optimal retention. This is the precise mechanical force required to compress the seals, and thereby achieve critical durability metrics. Traditional screws were too large for the bottom module and would negatively impact RF performance and aesthetics. Our solution was to devise an entirely new system consisting of a sliding wedge mechanism concealed within the band attachment ports that creates two crucial retention points. Ensuring uniform pressure across the internal gaskets was critical and maintaining the radial seal with only two retention points required extreme precision. To achieve this, we conducted extensive tolerance analysis starting with the o-ring seals to account for manufacturing variations in every component. This ensured that even with minuscule dimensional part variances, the product would still meet our quality and reliability standards and preserve water seal integrity—even after a repair.
We developed all of these solutions to eliminate the repair frustration that adhesive-based designs often bring and we surprised even ourselves with the results. We’ve even published a publicly accessible repair manual to support customers and technicians alike. Beyond that, we are deeply moved by iFixit’s recent teardown declaring that “Pixel Watch 4 Is the Most Repairable Smartwatch on the Market” with a 9/10 score and appreciate their partnership in making genuine parts available for it and other Google products.
Creating a highly repairable smartwatch wasn’t easy and required deep thinking and collaboration across many teams. We’ve learned that each product category poses different constraints. As we explore future product categories, each will require a unique combination of design architecture, technology, specialized components, and materials, and it takes time to develop those solutions. When they are ready, putting those solutions together in a product that is better in every way is always the best path to delight customers.
We hope Pixel Watch 4 empowers our customers to embrace product longevity and delights every user and technician who embarks on a repair. It’s been a rewarding journey for us, and we hope what we’ve created inspires designers and engineers everywhere to pursue even further innovation in repairable design.
