Model of Piezoelectric Power Harvesting Beam

Piezoelectric materials can be used as mechanisms to transfer mechanical energy, usually ambient vibration into electrical energy that can be stored and used to power other devices. With the recent advances in wireless and MEMS technology, sensors can be placed almost anywhere necessary. Since these devices are wireless it becomes necessary that they have their own power supply. This power supply in most cases is the conventional battery, however problems can occur when using batteries because of their finite life span. When the battery is extinguished of all its power, the sensor must be retrieved and the battery changed. Because wireless sensors are developed so that they can be placed in remote locations such as structural sensors on a bridge or GPS tracking devices on animals in the wild, obtaining the sensor simply to replace the battery can become a very expensive task. Therefore, if a method of obtaining the untapped energy surrounding these sensors was implemented, significant life could be added to the power supply. One method is to use piezoelectric materials to obtain energy lost due to vibrations of the test specimen. This captured energy could then be used to prolong the life of the power supply or in the ideal case provide endless energy for the sensors lifespan. The goal of this study is to develop a model of the piezoelectric power harvesting device. This model would simplify the design procedure necessary for determining the appropriate size and vibration levels necessary for sufficient energy to be produced and supplied to the electronic devices. An experimental verification of the model is also performed to ensure its accuracy.