How to read motion sensor (accelerometer) data?

Low cost motion sensors usually deploy 3-dimensional (3D) accelerometers to track the motion and activities of the user. The sensor monitors the acceleration (including gravity), so it can detect real motions (with significant acceleration) as well as change in orientations (or postures). The motion sensor is usually attached to head, body trunk, or on limbs.  Running, jogging, walking are easily tracked to provide pedometer or equivalent functionality. It's also very effective in detection of "dozing off" when the subject is drowsy and goes into micro-sleep episodes. Because micro-sleep relaxes many muscles, the head and body in a upright position can lose balance momentarily, and subsequent arousal (awareness of losing bodily balance) will break the micro-sleep back into awake state and to re-balance the head and body posture. This can be useful tool to determine how tired a person is, and how effective the user's meditation session had been.

Posture and Activity

  • Good health: good posture, adequate activity

Our spine routes and protects our nervous system from head to the rest of the body, while bearing the full weight of our head, body, upper limbs through all the activities we do throughout our life. Prolonged poor postures tend to degrade, damage and deform our spine and associated muscles and ligaments, create pressure points to nervous pathways, and cause long term problems to all our internal organs regulated by the nervous system.

Humans in modern society tend to have too little exercises and movements already. Furthermore, the advent of technology and its addicted usage, generally creates the exact "prolonged poor posture" condition that's detrimental to our spine. For example, working in front of computer monitor, typing on the keyboard, watching tiny characters, graphics and videos on tablet or smart phone screens, we all tend to stretch our head forward and down, putting lot of stress on our neck and the rest of our spine. We hump our body forward, further bending and stressing our spine. To minimize injury and accumulated damage, we need to keep our head straight up and our spine straight up most of the time, or at least more of the time, whether in motion or in static posture.

Integrated accelerometer (or G sensor) provides low cost, accurate and convenient tool to track our head and body's activities and postures, when attached to the best locations, such as center top of forehead or at center of chest for monitoring throughout the day and during sleep. With awareness aided by bio-sensor tool, determined practice and patience, everyone can improve one's posture and have adequate movements and activities for better health and quality of life.