Work vehicle and method for controlling work vehicle

1. A work vehicle comprising:

a work implement having a bucket;

a main body to which the work implement is attached, and having a cab; and

a bucket position detector configured to detect a position of the bucket;

a display device provided in the cab and configured to overlay and display work assistance information on an actual view of a work site; and

a display controller configured to cause the display device to display, on the actual view of the work site and adjacent to a right side and a left side of the bucket as seen from the cab, the overlaid work assistance information relevant to finishing excavation when a distance between the position of the bucket detected by the bucket position detector and design topography falls within a predetermined value, and display, on the actual view of the work site and adjacent to at least one of the right side and the left side of the bucket as seen from the cab, the overlaid work assistance information relevant to rough excavation when the distance does not fall within the predetermined value.

2. The work vehicle according to claim 1 , wherein the display controller changes displaying of the overlaid work assistance information on the display device when the distance between the position of the bucket and the design topography falls within the predetermined value.

3. The work vehicle according to claim 1 , wherein

the display controller further includes a following process unit configured to display the overlaid work assistance information such that the overlaid work assistance information moves following movement of the bucket, and

when the distance between the position of the bucket and the design topography falls within the predetermined value, the display controller increases in number the overlaid work assistance information displayed on the display device.

4. The work vehicle according to claim 1 , wherein the display controller causes the display device to display the overlaid work assistance information relevant to the finishing excavation including at least one of i) a facing angle compass and ii) a lateral cross section on the left side of the bucket as seen the cab and display the overlaid work assistance information relevant to the finishing excavation including a bar indicator showing the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab, and

wherein the display controller causes the display device to display the overlaid work assistance information relevant to the rough excavation including at least one of i) a direction of the design topography and ii) the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab.

5. The work vehicle according to claim 1 , wherein the overlaid work assistance information relevant to the finishing excavation further includes a bar indicator indicating distance between the design topography and teeth of the bucket.

6. The work vehicle according to claim 1 , wherein the overlaid work assistance information relevant to the rough excavation includes at least one of a distance between the design topography and teeth of the bucket and a bar showing a state of a progress of a work.

7. The work vehicle according to claim 1 , wherein the overlaid work assistance information relevant to the finishing excavation includes at least a facing angle compass and a lateral cross section.

8. The work vehicle according to claim 1 , wherein the display controller causes the display device to display the overlaid work assistance information relevant to the finishing excavation including i) a facing angle compass and ii) a lateral cross section on the left side of the bucket as the cab and display the overlaid work assistance information relevant to the finishing excavation including i) a bar indicator showing the distance between the position of the bucket and the design topography, ii) a direction of the design topography, and iii) the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab on the right side of the bucket as seen from the cab, and

wherein the display controller causes the display device to display the overlaid work assistance information relevant to the rough excavation including i) the direction of the design topography and ii) the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab.

9. A method for controlling a work vehicle comprising: a work implement having a bucket; and a display device provided in a cab and configured to overlay and display work assistance information on an actual view of a work site, the method comprising the steps of:

detecting a position of the bucket; and

displaying, on the actual view of the work site and adjacent to a right side and a left side of the bucket as seen from the cab, the overlaid work assistance information relevant to finishing excavation when a distance between the position of the bucket detected and design topography falls within a predetermined value, and displaying, on the actual view of the work site and adjacent to at least one of the right side and the left side of the bucket as seen from the cab, the overlaid work assistance information relevant to rough excavation when the distance does not fall within the predetermined value.

10. The method according to claim 9 , wherein the overlaid work assistance information relevant to the finishing excavation further includes a bar indicator indicating distance between the design topography and teeth of the bucket.

11. The method according to claim 9 , wherein the overlaid work assistance information relevant to the rough excavation includes at least one of a distance between the design topography and teeth of the bucket and a bar showing a state of a progress of a work.

12. The method according to claim 9 , wherein the overlaid work assistance information relevant to the finishing excavation includes at least a facing angle compass and a lateral cross section.

13. The method according to claim 9 , wherein displaying the overlaid work assistance information relevant to the finishing excavation includes displaying at least one of i) a facing angle compass and ii) a lateral cross section on the left side of the bucket as seen the cab and displaying a bar indicator showing the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab, and

wherein displaying the overlaid work assistance information relevant to the rough excavation including at least one of i) a direction of the design topography and ii) the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab.

14. The method according to claim 9 , wherein displaying the overlaid work assistance information relevant to the finishing excavation includes displaying i) a facing angle compass and ii) a lateral cross section on the left side of the bucket as seen the cab and displaying i) a bar indicator showing the distance between the position of the bucket and the design topography, ii) a direction of the design topography, and iii) the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab, and

wherein displaying the overlaid work assistance information relevant to the rough excavation including at least one of i) the direction of the design topography and ii) the distance between the position of the bucket and the design topography on the right side of the bucket as seen from the cab.