https://qooah.com/2014/05/12/sennheiser-%e5%ae%a3%e4%bd%88%e5%8a%a0%e5%85%a5-google-%e7%9a%84-project-ara-%e6%a8%a1%e5%a1%8a%e6%89%8b%e6%a9%9f%e9%ab%94%e7%b3%bb/