Research note on gravity artifact reduction in IMU signals using Madgwick orientation estimation
Year: 2026
Type: article
Abstract: Objective Gravitational artifacts bias Inertial Measurement Unit (IMU) signals, complicating applications such as Seismocardiography (SCG). This study aimed to validate a gravity-artifact reduction algorithm using Madgwick orientation estimation in a controlled, physics-based simulation. Results A computational phantom was developed using the PyBullet physics engine to generate paired datasets of gravity-free acceleration and simulated IMU signals (with gravitational artifacts). The Madgwick Attitude and Heading Reference System (AHRS) filter was applied to estimate the sensor orientation, followed by a low-pass-filtered gravity projection to subtract artifacts. The gravity-removed acceleration closely matched the gravity-free reference across all axes. Absolute mean differences were consistently below 0.006 m/s 2 , and Pearson correlation coefficients exceeded 0.98. Cross-correlation analysis revealed zero temporal lag, while Bland-Altman analysis showed no proportional bias. The highest precision was observed along the gravitational z -axis. These simulation-only results represent an upper bound under idealized conditions. Experimental validation remains necessary before practical deployment.
Source: BMC Research Notes
Authors: Moritz Toppmöller, Urs-Vito Albrecht
Institution: Bielefeld University
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,690
OpenAlex ID: W7167340252