日韩亚洲网,中文字字幕在线中文乱码电影,亚洲最大久久,91九色福利,久久婷婷国产精品,六月综合网,成人精品免费在线观看

The first is brewing pedometer by Italy's Leonard Da Vinci, but the earliest pedometer is in Da Vinci 150 years after the 1667 production. In the middle ages and modern times, not a pedometer is widely used, because people do not know its purpose. This shows that the invention of the machine is not as important as finding it for the use of human beings. The pedometer is mainly used for sports and walking pace analysis record. usually as a step by step pendulum principle, the use of mechanical switch detection pace increase, and with a simple counter. If the sloshing of these devices, you can hear a metal ball slide back and forth, or a pendulum swinging ring when the block. This mechanical pedometer has faded out of history, it is replaced by the electronic pedometer pedometer was first brewed by Italy's Leonard Da Vinci, but the earliest pedometer is in Da Vinci 150 years after the 1667 production. In the middle ages and modern times, not a pedometer is widely used, because people do not know its purpose. This shows that the invention of the machine is not as important as finding it for the use of human beings.The pedometer is mainly used for sports and walking pace analysis record. Usually as a step by step pendulum principle, the use of mechanical switch detection pace increase, and with a simple counter. If the sloshing of these devices, you can hear a metal ball slide back and forth, or a pendulum swinging ring when the block. This mechanical pedometer has faded out of history, it is replaced by the electronic pedometer