An Experimental Investigation of Power Scavenging from Human Walking

Energy harvesting or energy scavenging is the process of extracting energy of the surrounding environment, through various methods. No need to replace worn-out batteries and reducing maintenance costs and the use of medical devices within the body, are the important reasons for using energy harvesters. Piezoelectric materials are a class of smart materials that convert mechanical strain into electrical voltage and produce higher power density compared with other materials. Thus piezoelectric materials, are the main options in energy harvesting from vibration and mechanical movements. For energy harvesting and storage, shoe heels are suitable sources of mechanical stress, deformation and vibration during human walking. The purpose of this paper is to examine the possibility of using piezoelectric materials in footwear as a power source for charging the battery. The results of the tests, show that the use of piezo-ceramic converter for energy harvesting from the pressure of feet walking, can produce maximum power of 55mW. It will takes 19 hours to charge a rechargeable battery with a voltage of 2.1 volts and a current of 900 mA.