Apparatus and methods for ultrasonic sensor navigation

Patent metadata

Field	Value
Publication number	US-10184797-B2
Application number	US-201615005635-A
Country	US
Kind code	B2
Filing date	Jan 25, 2016
Priority date	Dec 18, 2015
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

An apparatus and methods are disclosed for determining a navigational constraint for a portable device using an ultrasonic sensor. The navigational constraint may be used to supplement other navigational solutions or may be used independently. The ultrasonic sensor may provide a plurality of samples to be processed to determine the constraint. Processing the ultrasonic samples may include performing a flow analysis regarding detected external objects. Determining the constraint may include any or all of determining a context for usage, distinguishing usage modes, estimating relative heading changes, and estimating misalignment angle between device and platform needed to determine direction of motion of the platform and determining a speed of the portable device from the samples.

First claim

What is claimed is:

1. A method for navigating with a device comprising:
processing a sequence of samples from an ultrasonic sensor of the device, wherein the processing comprises performing an ultrasonic flow analysis, wherein performing the ultrasonic flow analysis comprises determining change in relative location to an external object;
determining a navigational constraint for the device based at least in part on the processed sequence of samples, the determined navigational constraint consisting of at least one of:
a) a device angle;
b) a misalignment angle of the device with respect to a direction of motion;
c) relative heading changes obtained with respect to the external object;
d) a speed of the device, wherein processing the sequence of samples from the ultrasonic sensor further comprises determining a distance to the external object by ranging, wherein ranging is an ultrasonic ranging that measures the distance to the external object, and wherein the speed of the device is estimated based at least in part on the ultrasonic flow analysis and the determined distance to the external object; and
e) a context for the device, wherein the context is determined as consisting of at least one of:
i) being static;
ii) fidgeting motion; and
iii) device usage; and

providing a navigation solution for the device based at least in part on the determined navigational constraint.

2. The method of claim 1 , wherein determining the navigational constraint comprises estimating the device angle.

3. The method of claim 1 , wherein determining the navigational constraint comprises estimating the misalignment angle of the device with respect to a direction of motion.

4. The method of claim 3 , wherein the device further comprises inertial sensors, wherein the method further comprises a navigation routine using inertial sensors for providing the navigational solution and wherein the navigational constraint is applied to the navigational solution provided by the inertial navigation routine.

5. The method of claim 4 , further comprising processing the sequence of samples from the ultrasonic sensor using a Doppler analysis to determine a speed of the device, wherein the determined speed is applied to the navigational solution.

6. The method of claim 3 , wherein processing the sequence of samples from the ultrasonic sensor further comprises determining a distance to at least one of the external object and an additional external object by ranging, wherein ranging is an ultrasonic ranging that measures the distance to the external object, and wherein the device further comprises a gyroscope, further comprising estimating the speed of the device based at least in part on the ultrasonic flow analysis and the determined distance to at least one of the external object and the additional external object, and providing the navigational solution based at least in part on the estimated speed, the estimated misalignment angle and information from the gyroscope.

7. The method of claim 3 , wherein processing the sequence of samples from the ultrasonic sensor further comprises determining a distance to at least one of the external object and an additional external object by ranging, wherein ranging is an ultrasonic ranging that measures the distance to the external object, and wherein the device further comprises a magnetometer, further comprising estimating the speed of the device based at least in part on the ultrasonic flow analysis and the determined distance to at least one of the external object and the additional external object, and providing the navigational solution based at least in part on the estimated speed, the estimated misalignment angle and information from the magnetometer.

8. The method of claim 1 , wherein determining the navigational constraint comprises estimating relative heading changes obtained with respect to at least one of the external object and an additional external object.

9. The method of claim 8 , wherein the device further comprises inertial sensors, wherein the method further comprises a navigation routine using inertial sensors for providing the navigational solution and wherein the navigational constraint is applied to the navigational solution provided by the inertial navigation routine.

10. The method of claim 9 , further comprising processing the sequence of samples from the ultrasonic sensor using a Doppler analysis to determine a speed of the device, wherein the determined speed is applied to the navigational solution.

11. The method of claim 1 , further comprising processing the sequence of samples from the ultrasonic sensor using a Doppler analysis, wherein determining the navigational constraint comprises estimating relative heading changes obtained with respect to at least one of the external object and an additional external object based at least in part on the Doppler analysis.

12. The method of claim 11 , wherein the device further comprises inertial sensors, wherein the method further comprises a navigation routine using inertial sensors for providing the navigational solution and wherein the navigational constraint is applied to the navigational solution provided by the inertial navigation routine.

13. The method of claim 12 , further comprising processing the sequence of samples from the ultrasonic sensor using a Doppler analysis to determine a speed of the device, wherein the determined speed is applied to the navigational solution.

14. The method of claim 1 , wherein processing the sequence of samples from the ultrasonic sensor further comprises determining a distance to at least one of the external object and an additional external object by ranging, wherein ranging is an ultrasonic ranging that measures the distance to the external object.

15. The method of claim 14 , wherein determining the navigational constraint includes estimating the speed of the device based at least in part on the ultrasonic flow analysis and the determined distance to the external object.

16. The method of claim 15 , wherein the device further comprises inertial sensors, wherein the method further comprises a navigation routine using inertial sensors for providing the navigational solution and wherein the navigational constraint is applied to the navigational solution provided by the inertial navigation routine.

17. The method of claim 15 , wherein estimating the speed includes deriving a scale factor from the determined distance to the external object.

18. The method of claim 14 , wherein the device further comprises a supplemental sensor, further comprising processing a sequence of samples from the supplemental sensor to perform a flow analysis.

19. The method of claim 18 , further comprising determining an additional navigational constraint, wherein the additional constraint is a speed of the device, by estimating the speed of the device based at least in part on the flow analysis performed on the sequence of samples from the supplemental sensor and the determined distance to the external object from the ultrasonic sensor by ranging, wherein ranging is an ultrasonic ranging that measures the distance to the external object, wherein providing the navigational solution is based at least in part on the estimated speed from the supplemental sensor samples.

20. The method of claim 19 , wherein the device further comprises inertial sensors, wherein the method further comprises a navigation routine using inertial sensors for providing the navigational solution and wherein the navigational constraint from the flow analysis pe

Assignees

• Invensense Inc

Inventors

• Georgy Jacques
• Al-Hamad Amr
• Goodall Christopher

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title

• G01C21/20

  Instruments for performing navigational calculations (G01C21/24, G01C21/26 take precedence) · CPC title

• G01C21/165

  combined with non-inertial navigation instruments · CPC title

• H04W4/027

  using movement velocity, acceleration information · CPC title