Three dimensional object-localization and tracking using ultrasonic pulses
US11016167B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 2017 |
| Grant date | May 25, 2021 |
| Priority date | — |
| Expiry date | Feb 5, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W56/0015
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A tracking method includes displaying visual content on a screen of a head mounted display (HMD). One or more base stations may be stationary with respect to the screen while the visual content is being displayed. In contrast, one or more objects may move with respect to the screen while the visual content is being displayed. Time-difference-of-arrival (TDoA) and/or time-of-flight (ToF) may be measured for one or more ultrasonic pulses transmitted from the base station, one or more objects, or HMD. Position and orientation of the objects and HMD may be calculated based on the TDoA and ToF. Different frequencies of pulses may be used to locate the HMD and the objects. An electromagnetic synchronization signal from the HMD and/or base station may be used to measure TDoA. Position and orientation measurements may be fused with outputs from IMUS (inertial measurement units) to reduce jitter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.