Design Thinking – Thermal Solution for Alpha Edition
If you’ve read the project schedule update #2 we posted on Kickstarter and Indiegogo, I trust you’ve known the direction and status of Alpha and Delta series products. Via this update, we’d like to share something about LattePanda design thinking with a specific example, thermal design, to show you how our product team develops a key functional module and the story behind this process. Welcome for any suggestion from our backers or anyone, who is interested in our products after reading.
Get Straight to the point!
Let’s check the final design of Alpha and Delta series.
LattePanda Alpha and Delta edition product photo 1
LattePanda Alpha and Delta edition product photo 2
A beautiful product with subtle, unobtrusive thermal design is something we are going to deliver.
Though, appearance is always the first dimension to identify something. But the design is definitely not limited by one or two dimensions.
Let’s review the previous version and read the thinking behind it
LattePanda prototype thermal design v0.2
At the beginning, we want to develop a thermal solution, which is perfect for desktop development scenarios and embedded application both. It should be simple, stable! But we quickly realized a big problem. If a 7w TDP CPU runs applications with full load and you don’t want to lower the CPU speed, with standard fin heatsink, the size of heatsink should larger than 1,000 cm2, that’s the reason why the benchmark of some SBC products or laptops with passive cooling solution is lower than another product with the same CPU. However, the TDP of Alpha processor is about 15w.
So, if we want to unleash the real power of our processor, we must have different solutions for embedded and desktop usage. For Kickstarter backers and developers, we prefer to use the active cooling solution. And we kicked off another passive cooling design for commercial and embedded applications as a project branch.
Well then, next problem comes
Active cooling means noisy for most of people who don’t like it. If you do a simple search on google, you can easily find the definition of noise level.
|Noise Source||Decibel||Decibel Effect|
|Passenger car at 65 mph at 25 ft (77 dB);Living room music (76 dB); radio or TV-audio, vacuum cleaner (70 dB).||70||Arbitrary base of comparison. Upper 70s are annoyingly loud to some people.|
|Conversation in restaurant, office, background music, Air conditioning unit at 100 feet.||60||Half as loud as 70 dB. Fairly quiet.|
|Quiet suburb, conversation at home. Large electrical transformers at 100 feet.||50||One-fourth as loud as 70 dB.|
|Library, bird calls (44 dB); lowest limit of urban ambient sound||40||One-eighth as loud as 70 dB.|
|Quiet rural area.||30||One-sixteenth as loud as 70 dB. Very Quiet.|
|Whisper, rustling leaves||20|
Table source: www.industrialnoisecontrol.com
Basically, 20-30 dB is the nighttime ambient noise level, which is also our target noise control range. We tested more than 40-50 different fans and cooling solutions. The suitable design requires consideration from the following perspectives: fan blade shape, overall fan size (With the same air volume level, the bigger the fan, the smaller the noise), bearing rating, vent flow design, fins Design, motor speed matching. For these reasons, we did a lot of testing.
The size is the biggest challenge
No doubt, the size is the biggest challenge for our thermal solution and whole product design both. Meanwhile, we should keep the perfect performance. We don’t want the active cooling solution affect the expansibility and stackable hat design on the top of LattePanda products. So, the height of the complete thermal solution will be limited in 7mm (including the thickness of fin heatsink) to reach our target thermal efficiency. It is not that easy for this industry as we known. At least, rare teams do like what we do.
However, in terms of design and mechanical restrictions, the size of cooling module cannot exceed the range defined by our interface or the ideal product dimension we prefer. Means the width of the solution should be less than 58mm. In this way, user can read the silkscreen on the pin headers clearly. (Carefully checking the design picture attached above, you will see a small gap between the cooling module and pin headers.) So, we need delivery effective solution, considering how will you use the product at the same time and make sure the solution won’t affect the user experience.
So, eventually, the active thermal solution we designed is customized fin heatsink plus eddy fan. In this way, a complete solution balances the perfect cooling effect, unleashing the full power of CPU chosen and minimizing the noise with rigorously fan components and materials selection. That’s what we want and worth you to own.
Industry design is a kind of magic. Products have same features with different design, bringing completely different user experience for daily use. I think we are the first team, who is trying to combine a better and friendly industry design in this level and rich feature for products designed for developers.
So being the first is always not that easy, not to mention that industry design is a subject of lifelong learning.
We’ve taken a detour
Picture source: www.pinterest.com
We tried to incorporate some elements to the product design, this is our first design:
Heatsink for LattePanda Alpha and Delta beta design
But always feels like a kind of weird, hard to say. After a large numbers of attempts, we come to realize that as a board product design we need to focus on a design beauty of the component level. We found some inspiration.
Picture source: www.fugoo.com
The final design of customized thermal module
Thermal solution for LattePanda Alpha and Delta edition
To summary the thinking of this generation thermal solution, we will say it is “functional driven design with excellent material sense”. The final decision of materials and surface curvature is almost the only option we can see, considering about cooling effect, feature target, user experience, stronger visual hierarchy, assembling process and stability of structure.
So as we’ve changed the value and function positioning of the onboard thermal design, it’s necessary to do proper change on the Titan case at the same time. But the final product visual effect won’t be changed a lot as we shown. We will consider to adjust some details on Titan case design to adapt the air flow. Will keep the same design language on the case and update this part later.
Through thermal design is just a small piece of LattePanda Alpha and Delta products, which is just a part of necessary feature. But the thinking and development path are almost the same, like when we met with problems, how do we balance the design, testing, digging out the best solutions and insisting what’s we’d like to deliver. Lots of internal discussions and decisions are accompanied by the whole development process including functions, interface, layout, dimension, accessories, factory settings and so on.
We hope to make LattePanda the best product brand for developers, providing quality products and service to enjoy development process efficiently, inspiring ideas with great tools, and being a part of industry upgrading. We believe how we create our products bringing the biggest difference compared with our competitors, which is not easy to copy like design or code.
Thanks for your great support.