inertial orientation tracker having automatic drift compensation using an at rest sensor for tracking parts of a human body
US6786877B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 18, 2001 |
| Grant date | Sep 7, 2004 |
| Priority date | — |
| Expiry date | Apr 20, 2022 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2562/0219
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A self contained sensor apparatus generates a signal that corresponds to at least two of the three orientational aspects of yaw, pitch and roll of a human-scale body, relative to an external reference frame. A sensor generates first sensor signals that correspond to rotational accelerations or rates of the body about certain body axes. The sensor may be mounted to the body. Coupled to the sensor is a signal processor for generating orientation signals relative to the external reference frame that correspond to the angular rate or acceleration signals. The first sensor signals are impervious to interference from electromagnetic, acoustic, optical and mechanical sources. The sensors may be rate sensors. An integrator may integrate the rate signal over time. A drift compensator is coupled to the rate sensors and the integrator. The drift compensator may include a gravitational tilt sensor or a magnetic field sensor or both. A verifier periodically measures the orientation of the body by a means different from the drift sensitive sate sensors. The verifier may take into account characteristic features of human motion, such as stillness periods. The drift compensator may be, in part, a …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.