Wireless communication for small floor pads to detect personnel activity

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Our laboratory has designed data acquisition systems to detect personnel activity using floor-based sensors, which we call the smart carpet. Therefore, we use a signal-scavenging technique, where the carpet sensor has two states: active or non active. Active state can occur when someone steps on a sensor otherwise it is non active. To improve the wireless communication between data acquisition boards, we implemented a Wi-Fi connectivity. We used two Wi-Fi boards, the Murata SN8200 and the Spark Core. The Murata SN8200 receives the sensors data from the data acquisition board and wirelessly displays it on an embedded webpage, unfortunately it was limited. The second board we used, the Spark Core board, sends the sensor data from the data acquisition board to the Internet then to the cloud. We developed carpet pads with four sensors as a source of the sensors data to the data acquisition board. We saved the sensor data with the timestamp on a local PC by using the Node JS code. Next, we sent TCP request to Google, received the request, and displayed it on the TCP Client using the command line interface. We also implemented a TCP Client/Server environment to exchange the sensor data between two Spark Core boards. Moreover, we tested the ability of powering the Spark Core from a 9 Volts battery. Later, we embedded the Spark Core with the data acquisition board in a one PCB board. In addition, we did an experiment to test our system. We activated the carpet pads by walking, used four carpet pads with four PCB boards, and placed them in four different locations. An HTML page displayed the sensor data from the four PCB boards. Finally, we set up a notification system to alert the caregiver for the new sensor data by sending an Email or SMS message.