Control system for work vehicle, control method, and work vehicle

• US 10,563,374 B2
• Filed: 07/25/2017
• Issued: 02/18/2020
• Est. Priority Date: 08/02/2016
• Status: Active Grant

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Hashimoto, Kazuhiro, Shimada, Kenjiro
• Primary Examiner(s): Shaawat, Mussa A
• Application Number:
  US15/658,867
• Publication Number:
  US 20180038069A1
• Time in Patent Office: 938 Days
• CPC Class Codes: E02F 3/847 using electromagnetic, optical or acoustic beams to determine the blade position, e.g. laser beams
• CPC Class Codes: E02F 9/205 Remotely operated machines, e.g. unmanned vehicles E02F3/8866 takes precedence
• CPC Class Codes: E02F 9/262 with follow-up actions to control the work tool, e.g. controller
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• CPC Class Codes: G05D 3/12 using feedback

Abstract

A current terrain acquisition device acquires current terrain information indicating the current terrain to be worked. A controller is configured to decide a virtual design surface that is located below the current terrain and has an inclination angle. The controller is configured to generate a command signal to the work implement of the work vehicle to move the work implement along the virtual design surface. The controller is configured to update the current terrain information with the current terrain acquisition device as the movement proceeds, and change the inclination angle with the updated current terrain information.

Claims

1. A control system for a work vehicle, the system comprising:

a current terrain acquisition device that acquires current terrain information indicating a current terrain to be worked; and

a controller configured to

decide a virtual design surface located below the current terrain, the virtual design surface having an inclination angle,

generate a command signal to a work implement of the work vehicle to move the work implement along the virtual design surface,

update the current terrain information with the current terrain acquisition device as movement proceeds, and

modify the inclination angle according to the updated current terrain information.

2. The control system for a work vehicle according to claim 1, wherein

the controller is further configured to decide the virtual design surface to decrease the inclination angle gradually, by repeatedly updating the current terrain and deciding the virtual design surface.

3. The control system for a work vehicle according to claim 2, wherein

the controller is further configured to decide the inclination angle of the virtual design surface to be equal to or greater than a predetermined lower limit value.

4. The control system for a work vehicle according to claim 3, wherein

the current terrain information includes height of the current terrain from a current position of the work vehicle to a point that is a predetermined terrain recognition distance away, and

the controller is further configured to decide the lower limit value from the terrain recognition distance and the height of the current terrain.

5. The control system for a work vehicle according to claim 1, wherein

the virtual design surface extends at the inclination angle in a travel direction of the work vehicle from a current position of the work vehicle.

6. The control system for a work vehicle according to claim 1, wherein

the controller is further configured to

update the current terrain when a predetermined ending condition is satisfied, and

decide the virtual design surface that is inclined at the inclination angle that is smaller than the inclination angle of the updated current terrain.

7. The control system for a work vehicle according to claim 6, wherein

the ending condition includes that the work vehicle travels in reverse over a distance equal to or greater than a specific distance.

8. A method for controlling a work vehicle, the method comprising:

acquiring current terrain information indicating a current terrain to be worked;

deciding an inclined virtual design surface located below the current terrain; and

generating a command signal to a work implement of the work vehicle to move the work implement along the virtual design surface,

the virtual design surface being decided so that an inclination angle of the virtual design surface gradually decreases, by repeatedly updating the current terrain and deciding the virtual design surface.

9. A work vehicle comprising:

a work implement; and

a controller configured to

decide an inclined virtual design surface located below a current terrain to be worked,

move the work implement along the virtual design surface, and

decide the virtual design surface so that an inclination angle of the virtual design surface gradually decreases, by repeatedly updating the current terrain and deciding the virtual design surface.

10. The work vehicle according to claim 9, further comprising

a position sensing device that senses a position of the work vehicle and outputs position information for the work vehicle to the controller,

the updating of the current terrain being performed with the position information for the work vehicle.