17 years of design. At first, there were many ideas, and many concessions were made due to restrictions such as cost and mass production requirements. The final mass production and the following design had an error of about 5%, but I was very grateful to the strong engineering team at that time, and finally restored many features that could not be realized at the beginning of the prediction. The biggest regret is that the interactive part of intelligence cannot be interfered too much because it is the definition of Mijia, and the software and hardware cannot be completely harmonious in the end.