An open source inertial sensor network with Bluetooth Smart

In this paper, an open source inertial sensor network is presented. The network has multiple sensor nodes connecting to a consumer electronic device with Bluetooth Smart. Each sensor node contains the following components: (a) an inertial sensor measuring acceleration, angular velocity, and magnetic field with good accuracy; (b) a microcontroller with capacity to handle real-time floating number calculations; (c) a Bluetooth Smart module broadcasting the data with low power consumption. The sensor nodes are designed to be small, allowing the users to wear them conveniently. For demonstration, a basic Personal Navigation System is developed using 4 of these sensor nodes and an Android smartphone. The experiments show that the sensor nodes could output accurate results with small noises when at rest or in slow motion. The example Personal Navigation System could measure total distance walked by a pedestrian with less than 10% error.