Body Position Sensor Basics

This article explains the basics, features, and manufacturers of body position sensors. A 3-axis digital accelerometer IC can be used as a body position sensor.

Introduction

Monitoring the positions of elderly and disabled individuals is crucial. Accelerometer sensors serve this purpose effectively. A body position sensor monitors five different positions: standing, sitting, supine (lying face upwards), inclined, left, and right.

Patients with conditions like sleep disorders and restless leg syndrome also require position monitoring during treatment. Analyzing movements during sleep can help identify sleep quality and irregular sleeping patterns. These sensors can also prevent falls or fainting by monitoring a patient’s position when they’re alone.

What is a Body Position Sensor?

Definition: A sensor, such as a 3-axis accelerometer, used to determine a patient’s position (standing, sitting, supine, inclined, left, and right).

These accelerometer-based sensors can be easily interfaced with microcontroller boards like Arduino Uno or Arduino Mega.

Features of a Body Position Sensor

The features/specifications of a 3-axis accelerometer (e.g., ADXL345 manufactured by Analog Devices) include:

• Functions as a 3-axis digital accelerometer
• Selectable range: ±2g / ±4g / ±8g / ±16g
• Up to 13-bit resolution (resolution increases with the “g” range)
• I2C and SPI serial interfacing
• Ultra-low power consumption (23 µA in measurement mode and 0.1 µA in standby mode at 2.5V)
• 32-level FIFO storage

Body Position Sensor Manufacturers

The following table lists features and part numbers from different body position sensor manufacturers: