Calibration of a system for tracking a writing instrument with multiple sensors
US6492981B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 2000 |
| Grant date | Dec 10, 2002 |
| Priority date | — |
| Expiry date | Nov 21, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0383
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
One embodiment of the writing instrument described herein comprises a pen-like device containing three accelerometers and three gyroscopes. Data from these sensors are processed via an Euler transform. Prior to using the writing instrument, the user holds the writing instrument in multiple predefined positions and sensor readings are taken. The sensor readings are mapped to the corresponding predefined positions. In addition, the sensor readings are compared to expected sensor readings to compensate for environmental variations such as altitude or temperature as well as for the possible tilt of a writing surface. The sensor readings are interpolated to map sensor readings other than those at the predefined positions to other writing instrument positions. When the user writes with the writing instrument, sensor outputs are used to track the writing instrument to define strokes made by the user. The data describing the strokes may be stored or processed to accomplish a variety of tasks including faxing a message, recording information, etc.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.