Method and apparatus for facilitating map data processing for industrial vehicle navigation

• US 8,589,012 B2
• Filed: 06/14/2011
• Issued: 11/19/2013
• Est. Priority Date: 06/14/2011
• Status: Active Grant

• Current Assignee: Crown Equipment Corporation
• Original Assignee: Crown Equipment Corporation
• Inventors: Wong, Lisa, Graham, Andrew Evan, Goode, Christopher W.
• Primary Examiner(s): Cheung, Mary
• Assistant Examiner(s): BERNS, MICHAEL ANDREW
• Application Number:
  US13/159,501
• Publication Number:
  US 20120323432A1
• Time in Patent Office: 889 Days
• Field of Search: 701/25, 701/23, 701/26
• US Class Current: 701/25
• CPC Class Codes: B66F 9/063 Automatically guided
• CPC Class Codes: G01C 21/206 specially adapted for indoor navigation
• CPC Class Codes: G01C 21/3841 Data obtained from two or more sources, e.g. probe vehicles
• CPC Class Codes: G01C 21/3848 Data obtained from both position sensors and additional sensors
• CPC Class Codes: G01C 21/3889 Transmission of selected map data, e.g. depending on route
• CPC Class Codes: G01C 21/3896 Transmission of map data from central databases
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• CPC Class Codes: G05D 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30
• CPC Class Codes: G05D 1/0297 by controlling means in a control room
• CPC Class Codes: G09B 29/006 Representation of non-cartographic information on maps, e.g. population distribution, wind direction, radiation levels, air and sea routes

Abstract

A method and apparatus for facilitating map data processing for industrial vehicle navigation is described. In one embodiment, the method of partitioning map data for industrial vehicle navigation includes segmenting map data associated with a physical environment into a plurality of sub-area maps, identifying a sub-area map that corresponds with a current vehicle location and navigating an industrial vehicle using the identified sub-area map.

Claims

1. A method of partitioning map data for industrial vehicle navigation in a physical environment, wherein:

the physical environment comprises static features representing objects that do not change within the physical environment and dynamic features representing objects that change within the physical environment;

the industrial vehicle comprises a mobile computer and a sensor array communicably coupled to the mobile computer;

the mobile computer comprises a central processing unit and a memory comprising an environment based navigation module, a feature selection module, map data representing static features within the physical environment, and a plurality of sub-area maps;

the sensor array comprises a plurality of devices mounted to the industrial vehicle for monitoring the physical environment and producing sensor data representing the physical environment; and

the method comprises

segmenting the physical environment, as represented by the map data, into a plurality of sub-areas with corresponding map data stored in the plurality of sub-area maps,

utilizing the environment based navigation module and environmental features extracted from the sensor data to determine a location of the industrial vehicle relative to a particular sub-area,

utilizing the environment based navigation module to derive respective pose uncertainties associated with the dynamic features based upon data comprising noise in the sensor data and uncertainty in the determined location of the industrial vehicle;

selecting a sub-area map for use by the environment based navigation module based on the determined location of the industrial vehicle,

updating the selected sub-area map to include dynamic features within the particular sub-area corresponding to the selected sub-area map based on environmental features in the sensor data produced by the sensor array and the respective pose uncertainties associated with the dynamic features within the particular sub-area,

utilizing the feature selection module to manage the addition of dynamic features to the sub-area map based on the respective pose uncertainties associated with the dynamic features,

utilizing the environment based navigation module, the sensor data, and the updated sub-area map to determine an updated location of the industrial vehicle, and

navigating the industrial vehicle using the updated sub-area map and the updated location of the industrial vehicle.

2. A method as claimed in claim 1 wherein the selected sub-area map is updated by using the feature selection module to eliminate features that are not currently visible within the sensor data.

3. A method as claimed in claim 1 wherein the selected sub-area map is updated by using the feature selection module to include only those features that are visible within the sensor data.

4. A method as claimed in claim 1 wherein the particular sub-area corresponds to an area of the physical environment within a field of view of the sensor array of the industrial vehicle.

5. A method as claimed in claim 1 wherein the method further comprises triggering an alarm when the uncertainty in the determined location of the industrial vehicle exceeds a defined degree of uncertainty.

6. A method as claimed in claim 1 wherein the dynamic features are used to update the selected sub-area map by superimposing vehicle centric measurements from the sensor array devices onto an estimated pose of the industrial vehicle with respect to a global coordinate system.

7. A method as claimed in claim 6 wherein the estimated pose of the industrial vehicle refers to a current vehicle state and comprises position data, orientation data, and velocity data.

8. A method as claimed in claim 1 wherein the sensor array comprises a camera.

9. A method as claimed in claim 1 wherein the sub-area map is selected by requesting the sub-area map from the mobile computer.

10. A method as claimed in claim 1 wherein the sub-area map is selected automatically when the industrial vehicle approaches the edge of a prior sub-area map.

11. A method as claimed in claim 1 wherein the mobile computer is in communication with a second industrial vehicle and the selected sub-area map is updated to include feature information that is communicated by the second industrial vehicle.

12. A method as claimed in claim 1 wherein:

the physical environment comprises a dynamic shared use area in which pallets are expected to be placed on a floor of the physical environment; and

the dynamic features of the physical environment represent pallets placed on the floor of the physical environment.

13. A method as claimed in claim 12 wherein the feature selection module is further utilized to update map data to indicate areas recently occupied by or cleared of placed or picked items.

14. A method of partitioning map data for industrial vehicle navigation in a physical environment, wherein:

the physical environment comprises a dynamic shared use area in which pallets are expected to be placed on a floor of the physical environment and comprises static features representing objects that do not change within the physical environment and dynamic features representing pallets placed on the floor of the physical environment;

the industrial vehicle comprises a mobile computer and a sensor array communicably coupled to the mobile computer;

the mobile computer comprises a central processing unit and a memory comprising an environment based navigation module, a feature selection module, map data representing static features within the physical environment, and a plurality of sub-area maps;

the sensor array comprises a plurality of devices mounted to the industrial vehicle for monitoring the physical environment and producing sensor data representing the physical environment;

the method comprises

segmenting the physical environment, as represented by the map data, into a plurality of sub-areas with corresponding map data stored in the plurality of sub-area maps;

utilizing the environment based navigation module and environmental features extracted from the sensor data to determine a location of the industrial vehicle relative to a particular sub-area;

utilizing the environment based navigation module to derive respective pose uncertainties associated with the dynamic features based upon data comprising noise in the sensor data and uncertainty in the determined location of the industrial vehicle;

selecting a sub-area map for use by the environment based navigation module based on the determined location of the industrial vehicle;

updating the selected sub-area map to include dynamic features within the particular sub-area corresponding to the selected sub-area map based on environmental features in the sensor data produced by the sensor array and the respective pose uncertainties associated with the dynamic features within the particular sub-area, and by using the feature selection module to eliminate dynamic features that are not currently visible within the sensor data;

utilizing the feature selection module to manage the addition of dynamic features to the sub-area map based on the respective pose uncertainties associated with the dynamic features and to update map data to indicate areas recently occupied by or cleared of placed or picked items;

utilizing the environment based navigation module, the sensor data, and the updated sub-area map to determine an updated location of the industrial vehicle; and

navigating the industrial vehicle using the updated sub-area map and the updated location of the industrial vehicle.