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Automatic Steering System And Automatic Steering Method
Abstract: This automatic steering system for a work vehicle is provided with: a steering/travel device which makes a left turn on the basis of a leftward steering amount in reference to the straight-ahead direction and which makes a right turn on the basis of a rightward steering amount in reference to a neutral position; a host-vehicle position calculation unit 55 which calculates the position of the host vehicle; a positional displacement calculation unit 57 which calculates the positional displacement on the basis of a travel route and the position of the host-vehicle; a vehicle body orientation calculation unit 56 which calculates the vehicle body orientation indicating the orientation of the vehicle body; an orientational displacement calculation unit 58 which calculates the orientational displacement on the basis of the travel route and the vehicle body orientation; a steering amount calculation unit 41 which calculates, on the basis of the positional displacement and the orientational displacement, a first steering amount that is a steering amount for resolving the positional displacement and the orientational displacement; and a steering amount restriction unit 42 which restricts the first steering amount on the basis of a second steering amount which represents the current steering amount.
Notices, Deadlines & Correspondence
Patent Information
Applicants
KUBOTA CORPORATION
Inventors
1. SAKAGUCHI, Kazuo
2. SANO, Tomohiko
3. YOSHIDA, Osamu
4. MARUO, Satoshi
5. NAKABAYASHI ,Takashi
6. NAKAJIMA, Tetsuya
Claims
1. An automatic steering system for a work vehicle that automatically travels along a predetermined travel route on a work site, comprising: 5 a steering travel apparatus for performing leftward turning based on a leftward steering amount with respect to a straight-forward direction and performing rightward turning based on a rightward steering amount with respect to the straight-forward direction; a subject vehicle location calculator for calculating a location of a 10 subject vehicle; a locational shifting calculator for calculating locational shifting from the travel route and the location of the subject vehicle; a vehicle body direction calculator for calculating a vehicle body direction that indicates a direction of a vehicle body; 15 a directional shifting calculator for calculating directional shifting from the travel route and the vehicle body direction; a steering amount calculator for calculating a first steering amount, which is the steering amount for correcting the locational shifting and the directional shifting, based on the locational shifting and the directional 20 shifting; and a steering amount limiter for limiting the first steering amount based on a second steering amount, which is the steering amount at present.
2. The automatic steering system according to claim 1, wherein the 25 steering amount limiter prohibits the steering amount calculator from calculating a steering amount causing a change from one side of left and right sides to the other side of the left and right sides over the straight-forward direction. 30 3. The automatic steering system according to claim 1 or 2, wherein the first steering amount is limited by the steering amount limiter when the travel route is a turning travel route.
4. The automatic steering system according to claim 3, wherein the first 35 steering amount is limited by the steering amount limiter when the location of the subject vehicle is present inside a turning route of the turning travel 29 route, and the first steering amount is not limited by the steering amount limiter when the location of the subject vehicle is present outside the turning route of the turning travel route. 5 5. The automatic steering system according to any one of claims 1 to 4, comprising a limitation remover for removing a limitation applied to the first steering amount by the steering amount limiter, wherein the limitation remover removes the limitation on the first steering amount and outputs a vehicle speed reduction instruction at the 10 same time.
6. The automatic steering system according to any one of claims 1 to 5, wherein the steering travel apparatus includes a left travel unit and a right travel unit whose speeds can be independently adjusted, and the steering 15 amount is a difference in speed between the left travel unit and the right travel unit.
7. An automatic steering system for allowing a work vehicle to automatically travel along a predetermined turning circle, comprising: 20 a reference point calculator for calculating a location of a reference point of the work vehicle; a reference straight line calculator for calculating, as a reference straight line, a straight line that passes through the center of the turning circle and the reference point; 25 a locational shifting amount calculator for calculating, as a locational shifting amount, a distance between the reference point and an intersection point at which the reference straight line and the turning circle intersect each other; a vehicle body direction calculator for calculating a vehicle body 30 direction that indicates a direction of the vehicle body of the work vehicle; a directional shifting amount calculator for calculating, as a directional shifting amount, an intersection angle between the vehicle body direction and a line that passes through the reference point and is orthogonal to the reference straight line; and 35 a steering controller for outputting a first steering amount that reduces the locational shifting amount and the directional shifting amount. 30
8. The automatic steering system according to claim 7, wherein the locational shifting amount calculator calculates the distance by subtracting the radius of the turning circle from a length of a portion of the reference 5 straight line between the center of the turning circle and the reference point. 9 The automatic steering system according to claim 7 or 8, wherein the steering controller computes the first steering amount through a PID control method or PI control method using a second steering amount, which is a 10 current steering amount, the locational shifting amount, and the directional shifting amount as input parameters, and outputs the first steering amount.
10. The automatic steering system according to any one of claims 7 to 9, wherein the turning circle is set such that an arc connects a pre-turning 15 travel route and a post-turning travel route that extend in different directions, and a turning circle for quick turning and a turning circle for slow turning are prepared so as to be capable of being selected as the turning circle. 20 11. The automatic steering system according to any one of claims 7 to 10, wherein the radius of a turning circle set in a subsequent instance of turning travel is adjusted based on a turning travel error in a previous instance of turning travel. 25 12. An automatic steering method for a work vehicle that automatically travels along a predetermined travel route on a work site, comprising: a step of calculating a location of a subject vehicle; a step of calculating locational shifting from the travel route and the location of the subject vehicle; 30 a step of calculating a vehicle body direction that indicates a direction of a vehicle body; a step of calculating directional shifting from the travel route and the vehicle body direction; a step of calculating a first steering amount, which is a steering 35 amount for correcting the locational shifting and the directional shifting, based on the locational shifting and the directional shifting; 31 a step of limiting the first steering amount based on a second steering amount, which is the steering amount at present; and a step of steering the work vehicle in accordance with the limited first steering amount. 5
13. The automatic steering method according to claim 12, wherein, when the first steering amount is limited, a steering amount causing a change from one side of left and right sides to the other side of the left and right sides over the straight-forward direction is prohibited. 10
14. The automatic steering method according to claim 12 or 13, wherein the step of limiting the first steering amount is performed when the travel route is a turning travel route. 15 15. The automatic steering method according to claim 14, wherein the first steering amount is limited when the location of the subject vehicle is present inside a turning route of the turning travel route, and the first steering amount is not limited when the location of the subject vehicle is present outside the turning route of the turning travel route. 20
16. The automatic steering method according to any one of claims 12 to
15. wherein removing a limitation on the first steering amount and outputting a vehicle speed reduction instruction are performed at the same time. 25
17. An automatic steering method for allowing a work vehicle to automatically travel along a predetermined turning circle, comprising: a step of calculating a location of a reference point of the work vehicle; a step of calculating, as a reference straight line, a straight line that 30 passes through the center of the turning circle and the reference point; a step of calculating, as a locational shifting amount, a distance between the reference point and an intersection point at which the reference straight line and the turning circle intersect each other; a step of calculating a vehicle body direction that indicates a direction 35 of the vehicle body of the work vehicle; a step of calculating, as a directional shifting amount, an intersection 32 angle between the vehicle body direction and a line that passes through the reference point and is orthogonal to the reference straight line; a step of outputting a first steering amount that reduces the locational shifting amount and the directional shifting amount; and 5 a step of steering the work vehicle in accordance with the first steering amount.
18. The automatic steering method according to claim 17, wherein, when the locational shifting amount is calculated, the distance is calculated by 10 subtracting the radius of the turning circle from a length of a portion of the reference straight line between the center of the turning circle and the reference point.
19. The automatic steering method according to claim 17 or 18, wherein, 15 when the first steering amount is output, the first steering amount is computed through a PID control method or PI control method using a second steering amount, which is a current steering amount, the locational shifting amount, and the directional shifting amount as input parameters, and output. 20
20. The automatic steering method according to any one of claims 17 to 19, wherein the turning circle is set such that an arc connects a pre-turning travel route and a post-turning travel route that extend in different directions, and a turning circle for quick turning and a turning circle for slow 25 turning are prepared so as to be capable of being selected as the turning circle.
21. The automatic steering method according to any one of claims 17 to 20, wherein the radius of a turning circle set in a subsequent instance of 30 turning travel is adjusted based on a turning travel error in a previous instance of turning travel. 33
Specification
WE CLAIM:
1. An automatic steering system for a work vehicle that automatically
travels along a predetermined travel route on a work site, comprising:
5 a steering travel apparatus for performing leftward turning based on
a leftward steering amount with respect to a straight-forward direction and performing rightward turning based on a rightward steering amount with respect to the straight-forward direction;
a subject vehicle location calculator for calculating a location of a 10 subject vehicle;
a locational shifting calculator for calculating locational shifting from the travel route and the location of the subject vehicle;
a vehicle body direction calculator for calculating a vehicle body
direction that indicates a direction of a vehicle body;
15 a directional shifting calculator for calculating directional shifting
from the travel route and the vehicle body direction;
a steering amount calculator for calculating a first steering amount, which is the steering amount for correcting the locational shifting and the directional shifting, based on the locational shifting and the directional 20 shifting; and
a steering amount limiter for limiting the first steering amount based on a second steering amount, which is the steering amount at present.
2. The automatic steering system according to claim 1, wherein the
25 steering amount limiter prohibits the steering amount calculator from
calculating a steering amount causing a change from one side of left and right sides to the other side of the left and right sides over the straight-forward direction.
30 3. The automatic steering system according to claim 1 or 2, wherein the
first steering amount is limited by the steering amount limiter when the travel route is a turning travel route.
4. The automatic steering system according to claim 3, wherein the first
35 steering amount is limited by the steering amount limiter when the location of the subject vehicle is present inside a turning route of the turning travel
29
route, and the first steering amount is not limited by the steering amount limiter when the location of the subject vehicle is present outside the turning route of the turning travel route.
5 5. The automatic steering system according to any one of claims 1 to 4,
comprising a limitation remover for removing a limitation applied to the first steering amount by the steering amount limiter,
wherein the limitation remover removes the limitation on the first steering amount and outputs a vehicle speed reduction instruction at the 10 same time.
6. The automatic steering system according to any one of claims 1 to 5,
wherein the steering travel apparatus includes a left travel unit and a right
travel unit whose speeds can be independently adjusted, and the steering
15 amount is a difference in speed between the left travel unit and the right travel unit.
7. An automatic steering system for allowing a work vehicle to
automatically travel along a predetermined turning circle, comprising:
20 a reference point calculator for calculating a location of a reference
point of the work vehicle;
a reference straight line calculator for calculating, as a reference
straight line, a straight line that passes through the center of the turning
circle and the reference point;
25 a locational shifting amount calculator for calculating, as a locational
shifting amount, a distance between the reference point and an intersection
point at which the reference straight line and the turning circle intersect each
other;
a vehicle body direction calculator for calculating a vehicle body 30 direction that indicates a direction of the vehicle body of the work vehicle; a directional shifting amount calculator for calculating, as a
directional shifting amount, an intersection angle between the vehicle body
direction and a line that passes through the reference point and is orthogonal
to the reference straight line; and
35 a steering controller for outputting a first steering amount that
reduces the locational shifting amount and the directional shifting amount.
30
8. The automatic steering system according to claim 7, wherein the
locational shifting amount calculator calculates the distance by subtracting the radius of the turning circle from a length of a portion of the reference 5 straight line between the center of the turning circle and the reference point.
9 The automatic steering system according to claim 7 or 8, wherein the
steering controller computes the first steering amount through a PID control method or PI control method using a second steering amount, which is a 10 current steering amount, the locational shifting amount, and the directional shifting amount as input parameters, and outputs the first steering amount.
10. The automatic steering system according to any one of claims 7 to 9, wherein the turning circle is set such that an arc connects a pre-turning 15 travel route and a post-turning travel route that extend in different
directions, and a turning circle for quick turning and a turning circle for slow turning are prepared so as to be capable of being selected as the turning circle.
20 11. The automatic steering system according to any one of claims 7 to 10, wherein the radius of a turning circle set in a subsequent instance of turning travel is adjusted based on a turning travel error in a previous instance of turning travel.
25 12. An automatic steering method for a work vehicle that automatically
travels along a predetermined travel route on a work site, comprising:
a step of calculating a location of a subject vehicle;
a step of calculating locational shifting from the travel route and the
location of the subject vehicle;
30 a step of calculating a vehicle body direction that indicates a direction
of a vehicle body;
a step of calculating directional shifting from the travel route and the vehicle body direction;
a step of calculating a first steering amount, which is a steering 35 amount for correcting the locational shifting and the directional shifting, based on the locational shifting and the directional shifting;
31
a step of limiting the first steering amount based on a second steering amount, which is the steering amount at present; and
a step of steering the work vehicle in accordance with the limited first steering amount. 5
13. The automatic steering method according to claim 12, wherein, when
the first steering amount is limited, a steering amount causing a change from
one side of left and right sides to the other side of the left and right sides over
the straight-forward direction is prohibited.
10
14. The automatic steering method according to claim 12 or 13, wherein
the step of limiting the first steering amount is performed when the travel
route is a turning travel route.
15 15. The automatic steering method according to claim 14, wherein the first steering amount is limited when the location of the subject vehicle is present inside a turning route of the turning travel route, and the first steering amount is not limited when the location of the subject vehicle is present outside the turning route of the turning travel route.
20
16. The automatic steering method according to any one of claims 12 to
15. wherein removing a limitation on the first steering amount and
outputting a vehicle speed reduction instruction are performed at the same
time.
25
17. An automatic steering method for allowing a work vehicle to
automatically travel along a predetermined turning circle, comprising:
a step of calculating a location of a reference point of the work vehicle; a step of calculating, as a reference straight line, a straight line that 30 passes through the center of the turning circle and the reference point; a step of calculating, as a locational shifting amount, a distance between the reference point and an intersection point at which the reference straight line and the turning circle intersect each other;
a step of calculating a vehicle body direction that indicates a direction 35 of the vehicle body of the work vehicle;
a step of calculating, as a directional shifting amount, an intersection
32
angle between the vehicle body direction and a line that passes through the reference point and is orthogonal to the reference straight line;
a step of outputting a first steering amount that reduces the
locational shifting amount and the directional shifting amount; and
5 a step of steering the work vehicle in accordance with the first
steering amount.
18. The automatic steering method according to claim 17, wherein, when
the locational shifting amount is calculated, the distance is calculated by
10 subtracting the radius of the turning circle from a length of a portion of the reference straight line between the center of the turning circle and the reference point.
19. The automatic steering method according to claim 17 or 18, wherein,
15 when the first steering amount is output, the first steering amount is
computed through a PID control method or PI control method using a second steering amount, which is a current steering amount, the locational shifting amount, and the directional shifting amount as input parameters, and output. 20
20. The automatic steering method according to any one of claims 17 to
19, wherein the turning circle is set such that an arc connects a pre-turning
travel route and a post-turning travel route that extend in different
directions, and a turning circle for quick turning and a turning circle for slow
25 turning are prepared so as to be capable of being selected as the turning circle.
21. The automatic steering method according to any one of claims 17 to
20, wherein the radius of a turning circle set in a subsequent instance of
30 turning travel is adjusted based on a turning travel error in a previous
instance of turning travel.
33
Documents
Application Documents
| # | Name | Date |
|---|---|---|
| 1 | 202047020178.pdf | 2020-05-13 |
| 2 | 202047020178-TRANSLATIOIN OF PRIOIRTY DOCUMENTS ETC. [13-05-2020(online)].pdf | 2020-05-13 |
| 3 | 202047020178-STATEMENT OF UNDERTAKING (FORM 3) [13-05-2020(online)].pdf | 2020-05-13 |
| 4 | 202047020178-REQUEST FOR EXAMINATION (FORM-18) [13-05-2020(online)].pdf | 2020-05-13 |
| 5 | 202047020178-PRIORITY DOCUMENTS [13-05-2020(online)].pdf | 2020-05-13 |
| 6 | 202047020178-POWER OF AUTHORITY [13-05-2020(online)].pdf | 2020-05-13 |
| 7 | 202047020178-FORM 18 [13-05-2020(online)].pdf | 2020-05-13 |
| 8 | 202047020178-FORM 1 [13-05-2020(online)].pdf | 2020-05-13 |
| 9 | 202047020178-DRAWINGS [13-05-2020(online)].pdf | 2020-05-13 |
| 10 | 202047020178-DECLARATION OF INVENTORSHIP (FORM 5) [13-05-2020(online)].pdf | 2020-05-13 |
| 11 | 202047020178-COMPLETE SPECIFICATION [13-05-2020(online)].pdf | 2020-05-13 |
| 12 | 202047020178-CLAIMS UNDER RULE 1 (PROVISIO) OF RULE 20 [13-05-2020(online)].pdf | 2020-05-13 |
| 13 | 202047020178-Proof of Right [13-08-2020(online)].pdf | 2020-08-13 |
| 14 | 202047020178-FORM 3 [11-11-2020(online)].pdf | 2020-11-11 |
| 15 | 202047020178-Correspondence_Form1_17-03-2021.pdf | 2021-03-17 |
| 16 | 202047020178-certified copy of translation [11-10-2021(online)].pdf | 2021-10-11 |
| 17 | 202047020178-FER.pdf | 2021-10-18 |
| 18 | 202047020178-FORM 3 [03-11-2021(online)].pdf | 2021-11-03 |
| 19 | 202047020178-OTHERS [26-11-2021(online)].pdf | 2021-11-26 |
| 20 | 202047020178-FORM-26 [26-11-2021(online)].pdf | 2021-11-26 |
| 21 | 202047020178-FER_SER_REPLY [26-11-2021(online)].pdf | 2021-11-26 |
| 22 | 202047020178-DRAWING [26-11-2021(online)].pdf | 2021-11-26 |
| 23 | 202047020178-COMPLETE SPECIFICATION [26-11-2021(online)].pdf | 2021-11-26 |
| 24 | 202047020178-CLAIMS [26-11-2021(online)].pdf | 2021-11-26 |
| 25 | 202047020178-ABSTRACT [26-11-2021(online)].pdf | 2021-11-26 |
| 26 | 202047020178-FORM 3 [24-12-2021(online)].pdf | 2021-12-24 |
| 27 | 202047020178-FORM 3 [10-03-2022(online)].pdf | 2022-03-10 |
| 28 | 202047020178-FORM 3 [25-08-2022(online)].pdf | 2022-08-25 |
| 29 | 202047020178-PatentCertificate31-08-2023.pdf | 2023-08-31 |
| 30 | 202047020178-IntimationOfGrant31-08-2023.pdf | 2023-08-31 |
Search Strategy
| 1 | SearchStrategy202047020178E_13-03-2021.pdf |