Development of a Self-Powered Hydraulic Sensing Node

Abstract

In modern industrial settings, a significant amount of energy is wasted in the form of sound, physical vibrations, and pressure variations in gases and liquids. Given the recent advances in low power processing and communication devices, there is now an opportunity to capture this energy and use it to power sensing and communication components. A device that is able to power itself using ambient energy would be an innovative replacement to wired or battery-powered sensors which can be costly and difficult to maintain. Past efforts in this area have been stymied by the low energy densities that are present in ambient sources such as light and vibrations, but pressure fluctuations in hydraulic systems offer a much denser energy source. Previous work developing a piezoelectric energy harvesting device has generated 2.6mW of power from a hydraulic test rig operating at a static pressure of 5.5 MPa with a 9-piston pump operating at 1500 RPM. This Hydraulic Pressure Energy Harvester (HPEH) device has the potential to generate power which could be used for remote sensing and communication purposes in a variety of hydraulic systems. This paper presents an implementation of a HPEH device connected to a communications system that allows it to store energy and communicate sensor readings via Bluetooth Low Energy. The levels of power that are produced by the energy harvester and consumed by the communication components are analyzed, with special attention paid to the power consumption of a connected microcontroller during different operations. Additionally, an evaluation of the wireless data transmission rates that can be supported by the power output of a HPEH device is included.