They put a smartphone next to a keyboard, and they had people type, and then their goal was to use the vibrations that were created by typing to measure the change in the accelerometer reading to determine what the person had been typing.
他们把手机放在键盘旁边， 然後他们让人们去打字， 而他们的目标是 利用打字而产生的震动 去测量加速规的数据的变化 由此来判断这个人输入的是什么。