Elevation change detection method with only accelerometer and gyroscope data
Publication Date: 2018-Mar-16
The IP.com Prior Art Database
Elevation Change Detection Method with Only Accelerometer and Gyroscope Data
A system that utilises only a gyroscope and an accelerometer to detect an elevation change, for a pedometer-based application. It relies upon the device making measurements to be placed within the user's hip trouser pocket, and makes use of the idea that said device will move in a rough parabolic arc as the leg swings per step.
This system first makes use of the accelerometer to monitor the user’s step swing; this is achieved by utilising existing research, and associated data, to ascertain where apexes of a step occur from raw accelerometer input. It is assumed the device containing the accelerometer will be placed in the user’s trouser pocket.
At each peak and trough of a user’s step, the device’s centre point can be approximated to have been swinging in a parabolic arc through 3D space, due to its location on the user. Thus, at each step apex ascertained from the raw accelerometer data, the gyroscope is utilised to take a tangent on this arc with respect to the ground.
This produces an angle, between roughly 0º to 90º for a step on a flat surface. The difference between the angles measured at a peak and trough per step can dictate the size and direction of said step – for example, an acute angle placing the foot down with roughly a 90º angle when starting a step would approximate walking up a stair. If the user takes a step when walking on a steeper incline, it would produce a more a...