Autonomous Mobile System

• US 20140309841A1
• Filed: 11/22/2011
• Published: 10/16/2014
• Est. Priority Date: 11/22/2011
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hara, Yoshitaka, Oshima, Akira, Ichinose, Ryoko, Yamamoto, Kenjiro
• Granted Patent: US 9,062,980 B2
• Time in Patent Office: Days
• US Class Current: 701/26
• CPC Class Codes: G01C 21/28 with correlation of data from several navigational instruments
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• CPC Class Codes: G01C 21/3848 Data obtained from both position sensors and additional sensors
• CPC Class Codes: G01C 21/3867 Geometry of map features, e.g. shape points, polygons or for simplified maps
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4808 Evaluating distance, position or velocity data
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0248 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0251 extracting 3D information from a plurality of images taken from different locations, e.g. stereo vision stereoscopic image analysis H04N13/00; depth recovery from images G06T7/593
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

The invention includes a shape detector and travel distance detector for measuring whether objects are present in set regions determined by dividing a three-dimensional space into a plurality of segments, a storage device into which map data is stored that indicates a region of the set regions that has been set as having a stationary object in the region, a determining section that determines, from frequency of the object detection by the shape detector during a predetermined time for each of the set regions, whether the object that has been detected in each set region is a stationary object or a moving object, and a localizer that localizes a vehicle “v” by matching the region that the determining section has determined to have a stationary object in the region, and the map data. Thus, highly accurate detection of positions can be realized, even in an environment with moving objects.

Claims

1. An autonomous mobile system for a mobile body which moves while localizing itself in a space, the system comprising:

measuring means for measuring whether objects are present or absent in each of regions determined by dividing the space into a plurality of segments according to a predetermined rule;

storage means into which map data is stored that indicates a region of the determined regions that has been set as having a stationary object in the region;

means for determining, from frequency of the object detection by the measuring means during a predetermined time for each of the determined regions, whether the object that has been detected in the region is a stationary object or a moving object; and

means for localizing the mobile body by matching the region having therein the stationary object which the determining means has determined to be present, and the region that was set in the map data as having a stationary object in the region.

2. The autonomous mobile system according to claim 1, wherein:

the storage means stores therein measurement count data and detection count data, the measurement count data denoting, for each of the regions, the number of times the measuring means has measured the presence/absence of an object at the different time of day during the predetermined time, the detection count data denoting, for each of the regions, the number of times the measuring means has detected an object at the different time of day during the predetermined time; and

the determining means calculates the frequency of the object detection, based upon the measurement count data and the detection count data for each of the determined regions.

3. The autonomous mobile system according to claim 1, further comprising:

map updating means that updates, in accordance with a result of the determination by the determining means, the region set in the map data as having a stationary object in the region.

4. The autonomous mobile system according to claim 1, wherein:

the measuring means, the determining means, and the localizing means are mounted on the mobile body;

the storage means is mounted in the storage means; and

the mobile body exchanges data with a management terminal through wireless communication.

5. The autonomous mobile system according to claim 1, wherein:

the measuring means is mounted on a plurality of mobile bodies including the mobile body; and

the storage means stores therein measurement count data and detection count data, the measurement count data denoting, for each of the regions, the number of times the measuring means has measured the presence/absence of an object at the different time of day during the predetermined time, the detection count data denoting, for each of the regions, the number of times the measuring means has detected an object at the different time of day during the predetermined time.

6. The autonomous mobile system according to claim 1, further comprising:

means for displaying a position of the mobile body which has been localized by the localizing means, and the map data.

7. The autonomous mobile system according to claim 1, wherein:

each of the regions is a region determined by dividing the space into a plurality of parallelepipeds.

9. The autonomous mobile system according to claim 2, wherein:

the determining means determines whether the objects detected in the regions are stationary objects or moving objects, depending upon a magnitude of a rate of the detection count for each of the regions to the measurement count.

10. The autonomous mobile system according to claim 9, wherein:

the determining means determines that if the magnitude of the rate is equal to or greater than a threshold β

, the object present in the region is a stationary object, and that if the magnitude of the rate is less than a threshold β

, the object present in the region is a moving object.

8. The autonomous mobile system according to claim, wherein:

the measuring means includes means that detects shape data of objects present around the mobile body, and means that detects a travel distance of the mobile body; and

the measuring means measures presence/absence of objects in each of the regions in accordance with the shape data and the travel distance.