Mobile Robot System

Patent metadata

Field	Value
Publication number	US-2016299509-A1
Application number	US-201315036270-A
Country	US
Kind code	A1
Filing date	Nov 15, 2013
Priority date	Nov 15, 2013
Publication date	Oct 13, 2016
Grant date	—

Abstract

The present invention provides a mobile robot system which predicts, in an environment in which mobile objects such as people come and go, a place at which the possibility that a mobile object may appear is high and a potential mobile object and can efficiently avoid collision with a mobile object. The mobile robot system includes an outside world sensor that measures a position of an object in a surrounding environment, a traveling unit that displaces an own position, and a control unit that controls the traveling unit. The mobile robot system is configured such that: history map data in which positions (object movement positions) at each of which an object has moved and velocity information of the object within a predetermined period are provided on map data indicative of a movement space of the robot; based on environment information obtained from the outside world sensor, a mobile object appearance point at which no mobile body exists at present but there is the possibility that a mobile body may appear in the future is recognized; the velocity information of an object which moved over a position in the neighborhood of the appearance point in the past is read out from the map data; a shape of a collision risk area which is an area in which the possibility that a mobile object may appear and collide with the robot in the future in response to the velocity information is high is determined; and the control unit controls at least one of an advancing direction and a velocity of the robot in response to a positional relationship between the collision risk area and the robot.

First claim

1 . A mobile robot system, comprising:
an outside world sensor configured to measure a position of an object in a surrounding environment; a traveling unit configured to displace an own position; and a control unit configured to control the traveling unit, wherein: history map data in which positions at each of which an object has moved and velocity information of the object within a predetermined period are provided on map data indicative of a movement space of the robot; based on environment information obtained from the outside world sensor, a mobile object appearance point at which no mobile body exists at present but there is the possibility that a mobile body may appear in the future is recognized; the velocity information of an object which moved over a position in the neighborhood of the appearance point in the past is read out from the map data; a shape of a collision risk area which is an area in which the possibility that a mobile object may appear and collide with the robot in the future in response to the velocity information is high is determined; and the control unit controls at least one of an advancing direction and a velocity of the robot in response to a positional relationship between the collision risk area and the robot.

2 . The mobile robot system according to claim 1 , wherein:
when velocity information of a mobile object is to be recorded into a velocity history map, a plurality of representative directions are provided by dividing an overall circumference at fixed angular intervals around an object movement position; one of the representative directions which is nearest to the direction of a velocity vector of the mobile object and a norm of the velocity vector are recorded at the position; and when a mobile object moves over the position by a plural number of times, a maximum value of the norm of mobile object velocity vectors measured till then is recorded.

3 . The mobile robot system according to claim 1 , wherein
the mobile object appearance point is at least one of a door, the back of a shield and a stationary object having a width/height equal to or smaller than a predetermined width/height set in advance.

4 . The mobile robot system according to claim 1 , wherein
in recognizing a door as a mobile object appearance point, if part of an object being obtained from the outside world sensor and having a width equal to or greater than a predetermined width set in advance belongs to an object movement position recorded in the velocity history map, then the part is recognized as a door.

5 . The mobile robot system according to claim 1 , wherein,
in recognizing a stationary object having a width/height equal to or smaller than a predetermined width/height as an appearance point, if at least part of the object belongs to an object movement position recorded in the velocity history map, then the position is decided as a mobile object appearance point.

Assignees

• Hitachi Ltd

Inventors

• UEDA Taishi
• Nakamura Ryosuke
• Amino Azusa

Classifications

• Y10S901/01

  Mobile robot · CPC title

• G05D1/024

  in combination with a laser (lasers per se H01S) · CPC title

• B25J9/1676

  Avoiding collision or forbidden zones · CPC title

• G05D1/0274 Primary

  using mapping information stored in a memory device (navigation using map-matching G01C21/30) · CPC title