Sonar Scanner

• US 20080205194A1
• Filed: 05/05/2008
• Published: 08/28/2008
• Est. Priority Date: 08/03/2000
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Allard, James, Chiappetta, Mark
• Granted Patent: US 7,688,676 B2
• Time in Patent Office: Days
• US Class Current: 367/93
• CPC Class Codes: B25J 13/006 by means of a wireless system for controlling one or several manipulators
• CPC Class Codes: B60G 2300/45 Rolling frame vehicles
• CPC Class Codes: B62D 61/10 with more than four wheels tractors of the low ground pressure type B62D49/002
• CPC Class Codes: B62D 61/12 with variable number of ground engaging wheels, e.g. with some wheels arranged higher than others, or with retractable wheels for manoeuvring purposes only B60S
• CPC Class Codes: G01S 15/108 using more than one pulse per sonar period
• CPC Class Codes: G01S 15/88 Sonar systems specially adapted for specific applications seismic or acoustic prospecting or detecting G01V1/00
• CPC Class Codes: G01S 7/52004 Means for monitoring or calibrating short-range imaging G01S7/5205
• CPC Class Codes: G01S 7/527 Extracting wanted echo signals Doppler systems G01S15/50

Abstract

Detecting an object using sound waves includes outputting a sound wave from a transducer, receiving an echo after outputting the sound wave, obtaining a threshold value based on the echo and plural other echoes that are within a predetermined range of the echo, and determining if the echo is a result of the sound wave based on the threshold value.

Claims

1. A method of detecting an object using sound waves, the method comprising:

outputting a sound wave from a single transducer;

receiving an echo after outputting the sound wave;

obtaining a threshold value based on the echo and plural other echoes that are within a predetermined range of the echo; and

determining if the echo is a result of the sound wave based on the threshold value.

2. The method of claim 1, wherein obtaining the threshold value comprises:

obtaining an average that is based on the echo and the plural other echoes; and

modifying the average using a scaling factor.

3. The method of claim 1, wherein the plural other echoes are adjacent in time to the echo.

4. An apparatus for detecting an object using sound waves, the apparatus comprising:

a single transducer to output a sound wave and to receive an echo following output of the sound wave; and

a processor to obtain a threshold value based on the echo and plural other echoes that are within a predetermined range of the echo, and to determine if the echo is a result of the sound wave based on the threshold value.

5. The apparatus of claim 4, wherein obtaining the threshold value comprises:

obtaining an average that is based on the echo and the plural other echoes; and

modifying the average using a scaling factor.

6. The method of claim 4, wherein the plural other echoes are adjacent in time to the echo.

7. A method comprising:

receiving plural reflections of corresponding emissions;

determining a threshold value based on the plural reflections;

comparing a target reflection to the threshold value, the target reflection comprising one of the plural reflections; and

determining if the target reflection is a valid reflection based on comparison to the threshold value.

8. The method of claim 7, wherein determining comprises averaging magnitudes of the plural reflections.

9. The method of claim 8, wherein determining comprises applying a scaling factor to an average of the magnitudes of the plural reflections.

10. The method of claim 7, wherein:

the plural reflections comprise a first reflection, followed by a second reflection, followed by a third reflection; and

the target reflection comprises the second reflection;

wherein the first reflection, the second reflection, and the third reflection are adjacent in time.

11. The method of claim 7, wherein the emissions comprise sound waves and the plural reflections comprise echoes of the sound waves.

12. The method of claim 7, wherein the emissions comprise laser beams, and the reflections comprise reflections of the laser beams.

13. An apparatus comprising:

a transducer to receive plural reflections of corresponding emissions; and

a processor to determine a threshold value based on the plural reflections, to compare a target reflection to the threshold value, the target reflection comprising one of the plural reflections, and to determine if the target reflection is a valid reflection based on comparison to the threshold value.

14. The apparatus of claim 13, wherein determining comprises averaging magnitudes of the plural reflections.

15. The apparatus of claim 14, wherein determining comprises applying a scaling factor to an average of the magnitudes of the plural reflections.

16. The apparatus of claim 13, wherein:

the plural reflections comprise a first reflection, followed by a second reflection, followed by a third reflection; and

the target reflection comprises the second reflection;

wherein the first reflection, the second reflection, and the third reflection are adjacent in time.

17. The apparatus of claim 13, wherein the emissions comprise sound waves and the plural reflections comprise echoes of the sound waves.

18. The apparatus of claim 13, wherein the emissions comprise laser beams, and the reflections comprise reflections of the laser beams.