Background

Having extensive experience designing products for the server and telecommunications market, we were excited at the opportunity to work with Stoke on the design of their next generation chassis.  Stoke finds new ways to solve new problems now emerging as a result of the unprecedented adoption of mobile broadband and the always-connected lifestyle.  Stoke Systems are carrier-class mobile broadband gateways specifically engineered for the complexity of tightly controlled, session-based mobile networks while providing throughput capacity of fixed-line network elements.

Stoke sought our expertise in Industrial Design for their new bezel as part of their mobile operator gateway which transfers mobile broadband traffic to WiFi when entering a building.  Stoke wanted to design a new chassis with a 14 slot, vertical board configuration in a 13 or 14 RU enclosure.  The boards needed to fit in the existing 5U horizontal card cage, or in the new vertical card cage of the 14U chassis, which had design details similar to the 5U chassis.

Challenge

One of the main challenges was creating boards that could run at 300 watts, for a total of 4200 watts that would need to be evenly distributed across the card cage.  Speck Design was involved in thermal testing to ensure that the chassis could handle power densities that exceed 4.0 cubic inches per watt.  Thermal design was a driving factor in the chassis development.  Therefore, we began with detailed thermal modeling, and testing and validation were performed early and often throughout the duration of the project.

Solution

In order to create a design language that was the same across all of their products, our ID team gained an understanding of Stoke’s messaging and how their products are used in the market place.  From early prototypes to 3D concept models, we incorporated design elements from Stoke’s existing chassis to maintain a consistent design language.  Through a series of brainstorms with Stoke, we presented concepts that reflected Stoke’s corporate identity.  The style boards that were created included potential materials, including glass, rivets, polished and uncoated metals, and concrete, for creating a realistic-looking bezel.  The team unanimously chose to use concrete.  Yes, that’s right, concrete. Stoke liked the choice of concrete because of its “gritty” look and feel that ultimately fit Stoke’s design language, which reflected durability and strength.  However, in order to incorporate concrete into the product, we had to create a tool to caste the concrete sample.  Following the first prototype, Stoke went directly into the pre-production phase with our existing design.

Speck Design created a solution for cable management that was both functional and true to the evolving form of the chassis through a series of ridged hooks with flexible retainers. The way we designed the chassis, 4 cables could exit each blade.  We could run the cables up from the blades and out either side, which added high ease of use plus flexibility.

Another element of the chassis was temperature testing and optimizing the cardguides for maximum airflow.  We conducted a series of tests and in the process discovered there was a "choked off" portion of the chassis.  Based on this discovery, we modified the design of the chassis to address the thermal problems.

Results

With over 50 chassis developments under our belt, Speck Design delivered a chassis like no other in the industry.  Using concrete, an urban inspired-vent treatment, and a clever cable management system, we delivered a product that the customer was excited about.  In addition, by addressing the thermal issues at the beginning of the project because of our ability to perform airflow simulations, Speck Design was able to make design changes early on that could positively affect the final thermal solution.  Speck Design’s chassis experience allowed us to deliver a refined product that saved Stoke time and gave them a peace of mind throughout the process.

PROJECT INFO

• Client:

  Stoke

• Project:

  WiFi Gateway Chassis

• Industry:

  Networking