Joint Axis Estimation for Fast and Slow Movements Using Weighted Gyroscope and Acceleration Constraints
Olsson F, Seel T, Lehmann D, Halvorsen K (2019)
Publication Type: Conference contribution
Publication year: 2019
Publisher: Institute of Electrical and Electronics Engineers Inc.
Conference Proceedings Title: FUSION 2019 - 22nd International Conference on Information Fusion
Event location: Ottawa, ON
ISBN: 9780996452786
Abstract
Sensor-to-segment calibration is a crucial step in inertial motion tracking. When two segments are connected by a hinge joint, for example in human knee and finger joints as well as in many robotic limbs, then the joint axis vector must be identified in the intrinsic sensor coordinate systems. There exist methods that identify these coordinates by solving an optimization problem that is based on kinematic joint constraints, which involve either the measured accelerations or the measured angular rates. In the current paper we demonstrate that using only one of these constraints leads to inaccurate estimates at either fast or slow motions. We propose a novel method based on a cost function that combines both constraints. The restrictive assumption of a homogeneous magnetic field is avoided by using only accelerometer and gyroscope readings. To combine the advantages of both sensor types, the residual weights are adjusted automatically based on the estimated signal variances and a nonlinear weighting of the acceleration norm difference. The method is evaluated using real data from nine different motions of an upper limb exoskeleton. Results show that, unlike previous approaches, the proposed method yields accurate joint axis estimation after only five seconds for all fast and slow motions.
Authors with CRIS profile
Involved external institutions
Uppsala University
Sweden (SE)
Technische Universität Berlin
Germany (DE)
Tecnológico de Monterrey (ITESM)
Mexico (MX)
Sweden (SE)
Technische Universität Berlin
Germany (DE)
Tecnológico de Monterrey (ITESM)
Mexico (MX)
How to cite
APA:
Olsson, F., Seel, T., Lehmann, D., & Halvorsen, K. (2019). Joint Axis Estimation for Fast and Slow Movements Using Weighted Gyroscope and Acceleration Constraints. In FUSION 2019 - 22nd International Conference on Information Fusion. Ottawa, ON, CA: Institute of Electrical and Electronics Engineers Inc..
MLA:
Olsson, Fredrik, et al. "Joint Axis Estimation for Fast and Slow Movements Using Weighted Gyroscope and Acceleration Constraints." Proceedings of the 22nd International Conference on Information Fusion, FUSION 2019, Ottawa, ON Institute of Electrical and Electronics Engineers Inc., 2019.
BibTeX: Download