Study regarding the optimal sensors placement on the body for human activity recognition

In this work we have proposed to make a study of the optimal number of sensors, and their optimal placement on the human body for proper recognition of certain body positions. In our experiment we used three-axis accelerometer sensor built into the intelligent watch Chronos eZ430 product of Texas Instruments. Studying a large part of the published work addressing this issue [1-11], we placed the three sensors as follows: the first on the right hand, the second on the right thigh and the third one, on the chest. The Chronos devices transmit the data collected, wireless, to three access points connected to an Arduino ChipKIT MAX32 microcontroller module. Data are transmitted either to a PC through a serial port, or can be stored on the SD-card. WiFi Shield module provides the ability to connect and communicate through wireless IEEE 802.11 networks with portable equipment (e.g. smart phones, tablets, etc.). The data were imported into Matlab and after processing and analysis, we can draw conclusions on how the three sensors can be used in the activity recognition. To recognize the type of activity we used an artificial neural network modeled in Matlab. This network has been configured according to the number of sensors that acquired data and the number of activities that we want to recognize.