TRACKING DYNAMIC ON-STAGE OBJECTS

• US 20150330778A1
• Filed: 05/19/2014
• Published: 11/19/2015
• Est. Priority Date: 05/19/2014
• Status: Active Grant

• Current Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Original Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Inventors: Sinha, Vikas Kumar, Omar, Nishant
• Granted Patent: US 9,921,058 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01B 21/00 Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
• CPC Class Codes: G06V 40/25 Recognition of walking or running movements, e.g. gait recognition
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources

Abstract

Methods and systems for dynamic tracking of on-stage objects using microelectromechanical systems (MEMS) presented herein do not require illumination to track a randomly moving object and are easily configurable for various stage sizes and for stages movable relative to the ground. In some instances, a tracking method includes determining an initial state of an MEMS motion tracker carried on a dynamic object, such as a performer. Acceleration and orientation information gathered by the motion tracker is monitored. A change of state in response to the monitored acceleration and orientation information is then determined. An instant state is calculated using the change of state and the initial state. Actuation signals based on the calculated instant state are generated for actuating a gimbal. The gimbal faces a device supported thereby toward the dynamic object.

Claims

1. A method, comprising:

determining an initial state of a motion tracker carried on a dynamic object;

monitoring acceleration and orientation information gathered by the motion tracker;

determining a change of state in response to the monitored acceleration and orientation information;

calculating an instant state using the change of state and the initial state; and

generating actuation signals based on the calculated instant state for actuating a gimbal supporting a device to face the device toward the dynamic object.

2. The method of claim 1, further comprising calibrating the motion tracker and the driving controller and setting known parameters corresponding to the initial state in the motion tracker when the dynamic object is at an initial reference location.

3. The method of claim 2, wherein the dynamic object is moving in a two dimensional plane including the initial reference location.

4. The method of claim 3, wherein the two dimensional plane is quantifiable in terms of a motion unit predefined by the dynamic object, wherein the motion unit is used in the calibration of the motion tracker and the driving controller.

5. The method of claim 4, wherein the motion unit is a walking step length of a stage performer.

6. The method of claim 1, wherein determining the initial state of the motion tracker further comprises calculating the initial state using data collected from one of an accelerometer, a gyroscope and a magnetometer within the motion tracker.

7. The method of claim 1, wherein determining the initial state of the motion tracker further comprises calculating the initial state using data collected from a combination of an accelerometer, a gyroscope and a magnetometer within the motion tracker.

8. The method of claim 1, wherein calculating the instant state further comprises determining a present velocity and a present acceleration of the dynamic object.

9. The method of claim 8, further comprising generating data regarding quaternions, heading, pitch, roll, yaw, linear acceleration, and gravity.

10. The method of claim 1, wherein determining the change of state further comprises sampling data about acceleration and orientation of the motion tracker at a constant frequency.

11. The method of claim 1, wherein calculating the instant state comprises superpositioning the change of state to the initial state wherein the superpositioning includes accumulating the change of state in a period of time onto the initial state for determining a change of location relative to a known location.

12. The method of claim 1, wherein the motion tracker is wearable by a human.

13. The method of claim 1, wherein the motion tracker is a microelectromechanical system including one of an accelerometer, a gyroscope and a magnetometer.

14. The method of claim 1, wherein the device comprises one of a photon emitter, a photon receiver, and a sound wave emitter.

15. The method of claim 1, further comprising transmitting signals about the calculated instant state via a wireless transceiver to a driving controller of the gimbal.

16. A system for tracking a moving dynamic object, the system comprising:

a motion tracker carried on a dynamic object, the motion tracker being set at an initial state and operable to gather data of acceleration and orientation for calculation of an instant state, the instant state being determined from a change of state;

a wireless transceiver transmitting signals to a driving controller, the signals representing the gathered data or the instant state;

a gimbal controlled by the driving controller generating driving signals from the instant state; and

a device supported by the gimbal, wherein the gimbal operable to orient the device to face the dynamic object based on the driving signals sent from the driving controller.

17. The system of claim 16, wherein the motion tracker and the driving controller are calibrated by setting known parameters corresponding to the initial state when the dynamic object is at an initial reference location.

18. The system of claim 16, wherein the motion tracker comprises one of an accelerometer, a gyroscope, and a magnetometer for gathering the data of acceleration and orientation.

19. The system of claim 16, further comprising a microcontroller operable using the gathered data to calculate the instant state by superpositioning the change of state to the initial state to determine a present velocity and a present acceleration of the dynamic object, wherein the change of state is sampled about acceleration and orientation of the motion tracker at a constant frequency.

20. The system of claim 16, wherein the driving controller is configured to process the gathered data to calculate the instant state by superpositioning the change of state to the initial state to determine a present velocity and a present acceleration of the dynamic object, wherein the change of state is sampled about acceleration and orientation of the motion tracker at a constant frequency.

21. The system of claim 16, wherein the dynamic object is a human performer and the motion tracker is wearable by the human performer moving in a two dimensional plane in a non-predicted pattern.

22. A stage tracking system comprising:

a wearable motion tracker carried by a human performer moving on a stage platform of a finite size, the wearable motion tracker including a microelectromechanical system for gathering data to calculate an instant state of the wearable motion tracker; and

a driving controller configured to receive motion signals from the wearable motion tracker and generate control signals, the motion signals representing the gathered data or the instant state.

23. The stage tracking system of claim 22, further comprising a directional device supported by a gimbal, the gimbal receiving the control signals generated by the driving controller and operable to direct the directional device toward the performer.

24. The stage tracking system of claim 22, wherein the microelectromechanical system further comprises:

an accelerometer, a gyroscope, and a magnetometer for sampling data to calculate the instant state, wherein calculation of the instant state is based on an initial state and a change of state regarding acceleration and orientation; and

a transceiver for transmitting the gathered data to the driving controller via a wireless connection to actuate the directional device to follow the moving performer using projection or reception.