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For almost 5 years, James Olander worked as Senior Systems Engineer for Lockheed Martin, a large aerospace company, leveraging his degrees in Aerospace and Space Systems Engineering to develop innovative satellite technology and launch vehicles.
But to be a small piece of a massive organization like Lockheed Martin, no matter how great the company or the work, has certain limitations. So eventually, James found himself working at TechShop in the Bay Area, surrounded by people who were quite literally building their own dreams.
经过多年的工作捕获一台笔记本电脑，詹姆斯被启发到开始建立一个人，他一直在设想，并知道可以解决一个广泛的问题：一种创新和符合人体工程学的笔记本电脑立场Roost。
The moment that shifted Roost from hobby to career? Showing a prototype to Pebble CEO Eric Migicovsky with Eric’s response, “You’ve拿到把这件事放在Kickstarter上。“
A few months laterRoost was up on Kickstarter，$ 189,983承诺2,448名支持者，从那时起，他售出超过10,000个单位。
Now James isworking on V2 of Roost。第二个版本的发展的最大变化是引入注射模具以增加产量。通过第一个栖息地，原型和生产单元都采用激光切割机和相同的材料加工，因此两者之间没有差异;如果原型破坏，那么生产单位会破裂。
通过注塑成型，这是一个完全不同的过程。您需要了解原型的结构元素，采用不同的材料和工具，然后通过测试和分析预测最终注塑部件的结构特征。
This is where James’ aerospace background goes to work. Using very intentional and detailed analysis, he’s able to assess the structural elements of his prototypes created with plastics, and then extrapolate those results to understand how an injection molded part will perform.
在这个硬件聚焦中，詹姆斯分享了他的过程的元素，利用了他的航空航天工程背景，使他能够设计具有高耐用性的产品，无需猜测。
了解您设计的关键组件
Before you do anything else, you have to understand the most critical components of your part design. As in, which structural elements are most important to the mechanical integrity of your product? “In aerospace if you launch a vehicle, you can’t go fix it,” James says. “It’s 10,000 miles in the air by the time you realize something’s wrong! So you better know, at least on paper, and have tested to an understood level the strength of it.”
For Roost, the most critical design components are strength and stiffness. The Roost stand is designed to be extremely strong and stable, for a lifetime of heavy usage. So that’s where James placed his focus.
我不知道如何在不知道我正在使用的材料的机械性质的情况下正确建立任何东西
了解他需要分析的物理性质，詹姆斯利用了他的背景。“在航空航天工程中，您以两种方式设计：优化刚度或优化力量，”詹姆斯说。““所以有两个物理属性来分析。有一种称为模量的刚度的衡量标准，并且当物质将破裂时，称为拉伸强度的量度。然后你每单位重量看这些属性 - 所以你看起来特定模量你看起来specific strength。Optimize these with material geometry to get the best part at lowest weight.”
Once you know the most critical components of your design and what you’re optimizing for in regards to structural integrity, you need to find the materials that maximize those properties.
Know Your Materials
In order to find the right materials, you need to understand the mechanical properties of the materials available. “I often ask for material property sheets from various manufacturers and they usually respond with, ‘why do you need that?” James shares. “That always leaves me confounded! Because to me, I don’t know how I could properly build anything without knowing the mechanical properties of the materials I’m working with.”
For the final production material, James is using glass-filled nylon, which replaces the carbon fiber used for the first Roost product and has very high stiffness. “Stiffness is really the most important component to optimize for since you don’t want your laptop to wobble at all on the stand,” James says. “So I chose a glass-filled material, which is used in car parts and will provide that critical stiffness.”
当然玻璃填充尼龙材料James used to iterate with for all his prototypes. So the main challenge for James in finding the right material to work with for his prototypes was to find something that would compare in stiffness to the glass-filled material. “I finally found a 3D printing material called Bluestone that’s actually very brittle,” James shares. “It doesn’t have very high strength, but it does have very high stiffness. Since the stiffness compares with that of the injection molded material and it doesn’t break under an un-abusive load, then with production material of the same stiffness and four times the strength, the structure will work in final production.”
通过栖息地，我实际上可以建立它并打破它，所以我知道它肯定会在哪里休息而不是理论上
Another new material James uses in this second version of Roost is silicone on the pivoting grip mechanism that latches to the laptop. “Silicon is interesting because it’s an A and a B component where you mix it together and a chemical reaction happens such that the final shape is permanent,” James notes. “Plastic, on the other hand, is in a constant, albeit slow, state of deforming.”
This is the kind of detailed analysis James uses in his process. He understands the properties of the material he’s working with, optimizing for one of the two critical elements in his design: strength and stiffness. This allows him to predict, through rigorous comparison and testing, what the final injection molded unit will be like before it’s produced.
验证您的机械设计
The advantage James had in designing Roost versus a satellite is he could understand the mechanical theory behind the design, but also physically test it before sending it off into the universe.
“With Roost, I can actually build it and break it so I know for sure where it will break instead of just theorizing,” James says. “Understanding your mechanical structure on paper and in CAD is one thing, but it’s just as critical, if you can, to test your theories with physical prototypes.”
Never assume you’re going to have it designed right on the computer
That said, James is a CAD wizard and he recognizes it’s a great tool to reduce the manual labor of your development process. “With this second version of Roost, I’ve been able to leverage the parametric model I’d already made to create tweaks in the geometry for me,” James shares. “Before it was really manual; I was going in and making all the little changes myself. Now I can just change one number and it recreates the whole thing.”
But translating that theoretical geometry into a real product is still another thing entirely. “Never assume you’re going to have it designed right on the computer, no way,” James emphasizes. “For a long time I was 3D printing different shapes out of different materials and judging, ‘well, if the injection molding material is going to be four times stronger but the same stiffness, and this one broke at 10 pounds that means it should hold up to about 40 pounds when molded.’ There were tons of these comparisons.”
因此，虽然纸张似乎如何优化刚度，然后比较3D印刷材料与注塑材料的相对强度，但詹姆斯的过程涉及大量的测试。他在不同的重量下测试了多种性质和价格点的多种材料，以利用最佳材料的信心。
然后来支撑他的国际泳联的预测分析l production parts, James plans to use a statistical analysis of fits on the first 25 injection molded units to validate the tolerances. “I’ll build a few parts with tolerances above and beyond what you would usually want for an injection mold because you get shrinkage,” James say. This will help to understand, for example, the tolerances needed for one of the components which is a perfect circle. “Perfect circles are not a good idea in injection molds, but it can be done,” James adds. “You just have to spend a lot of time tweaking the tool.”
利用材料数据表，CAD和工程理论，但不要低估物理测试这些材料，设计和理论的重要性。
The process James used to develop Roost is part theory and part hands-on engineering. He is absolutely detail-oriented when it comes to assessing the properties of his materials and the most important components of his design, but he’s also very hands-on when it comes to validating the mechanics of those designs.
因为有时理论失败了。例如，用于创建Roost V2的多个迭代的第一材料james不是在后敏感中最好的材料。他忽略了一些关键特征，进行了一些计算错误，并且属性与所需的最终生产强度无关。
The point is, be detailed in your theory and just as detailed in your validation of that theory; preparation is critical but mistakes are inevitable. Even for aerospace engineers.
