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.

A robotic mapping and tracking system including a robot and boundary posts are disclosed. The robot includes an ultrasonic transmitter, a processor and a camera component. The boundary posts are configured to be placed adjacent to a boundary of a working region. Each boundary post of the plurality of boundary posts includes an ultrasonic receiver. Time-of-flights of the ultrasonic waves are measured to identify distances in between the robot and boundary posts. The camera component of the robot captures an image of an environment of the robot. The processor of the robot analyzes the image of the environment and identifies at least a portion of the working region in front of the robot from the image. The processor of the robot determines a moving route based on the identified portion of the working region in front of the robot and the distances in between the robot and the boundary posts.

A positioning system has an initiator device configured for emitting a high-speed wireless signal, at least one reference device configured for receiving the high-speed wireless signal and emitting a low-speed wireless signal after receiving the high-speed wireless signal, at least one target device each having one or more components for receiving the low-speed wireless signals, and at least one engine configured for determining the position of each of the at-least-one target device by calculating the distance between the target device and each of the at-least-one reference device based on at least the times-of-arrival of the low-speed wireless signals, each time-of-arrival being the time that the corresponding low-speed wireless signal being received by the target device, and determining the position of the target device based on the calculated distances.

An AR/VR input device include a processor(s), an internal measurement unit (IMU), and a plurality of sensors configured to detect emissions received from a plurality of remote emitters. The processor(s) can be configured to: determine a time-of-flight (TOF) of the detected emissions, determine a first estimate of a position and orientation of the input device based on the TOF of a subset of the detected emissions and the particular locations of each of the plurality of sensors on the input device that are detecting the detected emissions, determine a second estimate of the position and orientation of the input device based on the measured acceleration and velocity from the IMU, and continuously update a calculated position and orientation of the input device within the AR/VR environment in real-time based on a Beyesian estimation (e.g., Extended Kalman filter) that utilizes the first estimate and second estimate.

A three-dimensional space detection system, including: a locating base station, a label device to be located, and a computing device. The locating base station synchronizes a base time point to the label device to be located, sends an ultrasonic signal to the label device to be located, rotationally sends a first laser plane signal about a first rotation axis, and rotationally sends a second laser plane signal about a second rotation axis perpendicular to the first rotation axis. The label device to be located synchronizes a base time point from the locating base station, detects the ultrasonic signal, the first laser plane signal and the second laser plane signal. The computing device determines the three-dimensional space coordinates of the label device to be located according to the time point at which the label device to be located detects the ultrasonic signal, the time point at which the label device to be located detects the first laser plane signal and the time point at which the label device to be located detects the second laser plane signal. The locating system enables precise indoor locating based on ultrasound and laser signals.

A three-dimensional space detection system, including: a locating base station, a label device to be located, and a computing device. The locating base station synchronizes a base time point to the label device to be located, sends an ultrasonic signal to the label device to be located, rotationally sends a first laser plane signal about a first rotation axis, and rotationally sends a second laser plane signal about a second rotation axis perpendicular to the first rotation axis. The label device to be located synchronizes a base time point from the locating base station, detects the ultrasonic signal, the first laser plane signal and the second laser plane signal. The computing device determines the three-dimensional space coordinates of the label device to be located according to the time point at which the label device to be located detects the ultrasonic signal, the time point at which the label device to be located detects the first laser plane signal and the time point at which the label device to be located detects the second laser plane signal. The locating system enables precise indoor locating based on ultrasound and laser signals.

A positioning system according to an embodiment of the above description includes a transmitter including a first transmitting unit and a second transmitting unit for transmitting a first signal and a second signal having different velocities, respectively; and a receiver including: a first receiving unit and a second receiving unit for measuring each time of reception of the first signal and the second signal; and a position determining unit for measuring a location of the transmitter using a difference in reception time of the first signal and the second signal.

A positioning system according to an embodiment of the above description includes a transmitter including a first transmitting unit and a second transmitting unit for transmitting a first signal and a second signal having different velocities, respectively; and a receiver including: a first receiving unit and a second receiving unit for measuring each time of reception of the first signal and the second signal; and a position determining unit for measuring a location of the transmitter using a difference in reception time of the first signal and the second signal.

An ultrawide band two-way ranging based positioning system includes a number of active tags each having a position, and a number of beacons configured for location of a position of a tag of the plurality of active tags. The active tags and the beacons are synchronized continuously to a common time base.

An ultrawide band two-way ranging based positioning system includes a number of active tags each having a position, and a number of beacons configured for location of a position of a tag of the plurality of active tags. The active tags and the beacons are synchronized continuously to a common time base.