Speed control and steering control assistant based on pitch status and roll status of autonomous driving vehicle

Patent metadata

Field	Value
Publication number	US-10569651-B2
Application number	US-201715595529-A
Country	US
Kind code	B2
Filing date	May 15, 2017
Priority date	May 15, 2017
Publication date	Feb 25, 2020
Grant date	Feb 25, 2020

Abstract

When generating a control command of an autonomous driving vehicle (ADV), a pitch status and/or a roll status of the road is determined. The control command is adjusted based on the pitch status and the roll status. For example, when an ADV is driving on an uphill or downhill road, a pitch status of the road is determined and a speed control command will be generated based on the pitch status of the road, such that the ADV have a similar acceleration rate as of driving on a flat road. Similarly, when the ADV is driving on a road that is tilted or rolled left or right, a roll status of the road is determined and a steering control command will be generated in view of the roll status of the road, such that the ADV have a similar heading direction as of driving on a flat road.

First claim

What is claimed is:

1. A computer-implemented method for operating an autonomous driving vehicle (ADV), the method comprising:
in response to detecting that an ADV is driving on a sloped road, determining a slope status of the road;
performing a lookup operation in a slope status to command (slope/command) mapping table based on a speed of the ADV;
in response to the lookup operation, locating a first mapping entry in the slope/command table and obtaining a first driving parameter from the first mapping entry, wherein the first mapping entry matches the speed of the ADV and includes a zero slope status representing a flat road;
deriving a first control command from a second mapping entry of the slope/command mapping table, wherein the second mapping entry matches the speed of the ADV, the slope status of the road, and the first driving parameter obtained from the first mapping entry, wherein deriving the first control command from the second mapping entry of the slope/command mapping table comprises:
locating a third mapping entry having a speed matching the speed of the ADV, a slope status matching the slope status of the road, and a second driving parameter equal to or less than the first driving parameter of the first mapping entry;
locating a fourth mapping entry having a speed matching the speed of the ADV, a slope status matching the slope status of the road, and a third driving parameter equal to or greater than the first driving parameter of the first mapping entry; and
deriving the first control command based on a second control command obtained from the third mapping entry and a third control command obtained from the fourth mapping entry; and

controlling the ADV using the first derived control command such that the ADV is driving on the sloped road as if driving on the flat road.

2. The method of claim 1 , wherein the slope/command mapping table comprises a plurality of mapping entries, wherein each mapping entry maps a particular speed and a particular slope status to a particular control command and a particular driving parameter.

3. The method of claim 1 , wherein deriving the first control command based on the second control command and the third control command comprises deriving the first control command using a linear regression algorithm based on a plurality of control commands associated with a plurality of mapping entries that match the speed of the ADV and the slope status and have a weighted driving parameter derived from both the second driving parameter and the third driving parameter that approximates the first driving parameter.

4. The method of claim 1 , wherein the slope/command mapping table is created based on driving statistics of a plurality of vehicles, which are captured while the vehicles are driving on different sloped and flat roads, including capturing speeds, slope statuses, control commands issued, and acceleration or heading directions at different points in time.

5. The method of claim 1 , wherein the slope status comprises a pitch status of the road, wherein the first driving parameter comprises a first acceleration, and wherein the derived first control command comprises a speed control command such that the ADV is to drive with comparable acceleration as if driving on the flat road.

6. The method of claim 1 , wherein the slope status comprises a roll angle of the road, wherein the first driving parameter comprises a first heading direction, and wherein the derived first control command comprises a steering command such that the ADV is to drive with comparable heading direction as if driving on the flat road.

7. A non-transitory machine-readable medium having instructions stored therein, which when executed by a processor, cause the processor to perform operations, the operations comprising:
in response to detecting that an autonomous driving vehicle (ADV) is driving on a sloped road, determining a slope status of the road;
performing a lookup operation in a slope status to command (slope/command) mapping table based on a speed of the ADV;
in response to the lookup operation, locating a first mapping entry in the slope/command table and obtaining a first driving parameter from the first mapping entry, wherein the first mapping entry matches the speed of the ADV and includes a zero slope status representing a flat road;
deriving a first control command from a second mapping entry of the slope/command mapping table, wherein the second mapping entry matches the speed of the ADV, the slope status of the road, and the first driving parameter obtained from the first mapping entry, wherein deriving the first control command from the second mapping entry of the slope/command mapping table comprises:
locating a third mapping entry having a speed matching the speed of the ADV, a slope status matching the slope status of the road, and a second driving parameter equal to or less than the first driving parameter of the first mapping entry;
locating a fourth mapping entry having a speed matching the speed of the ADV, a slope status matching the slope status of the road, and a third driving parameter equal to or greater than the first driving parameter of the first mapping entry; and
deriving the first control command based on a second control command obtained from the third mapping entry and a third control command obtained from the fourth mapping entry; and

controlling the ADV using the first derived control command such that the ADV is driving on the sloped road as if driving on the flat road.

8. The machine-readable medium of claim 7 , wherein the slope/command mapping table comprises a plurality of mapping entries, wherein each mapping entry maps a particular speed and a particular slope status to a particular control command and a particular driving parameter.

9. The machine-readable medium of claim 7 , wherein deriving the first control command based on the second control command and the third control command comprises deriving the first control command using a linear regression algorithm based on a plurality of control commands associated with a plurality of mapping entries that match the speed of the ADV and the slope status and have a weighted driving parameter derived from both the second driving parameter and the third driving parameter that approximates the first driving parameter.

10. The machine-readable medium of claim 7 , wherein the slope/command mapping table is created based on driving statistics of a plurality of vehicles, which are captured while the vehicles are driving on different sloped and flat roads, including capturing speeds, slope statuses, control commands issued, and acceleration or heading directions at different points in time.

11. The machine-readable medium of claim 7 , wherein the slope status comprises a pitch status of the road, wherein the first driving parameter comprises a first acceleration, and wherein the derived first control command comprises a speed control command such that the ADV is to drive with comparable acceleration as if driving on the flat road.

12. The machine-readable medium of claim 7 , wherein the slope status comprises a roll angle of the road, wherein the first driving parameter comprises a first heading direction, and wherein the derived first control command comprises a steering command such that the ADV is to drive with comparable heading direction as if driving on the flat road.

13. A data processing system, comprising:
a processor; and
a memory coupled to the processor to store instructions, which when executed by the processor, cause the processor to perform operations, the operations including:
in response to detecting that an autonomous driving vehic

Assignees

• Baidu Usa Llc

Inventors

• Zhu Fan
• Kong Qi
• Luo Qi
• Yu Xiang
• Hu Sen
• Zhuang Li
• Zhang Liangliang
• Zhu Weicheng
• Fan Haoyang
• Zhang Yajia
• Yang Guang
• Wang Jingao

Classifications

• B60W2050/006

  Interpolation; Extrapolation · CPC title

• B60W2710/18

  Braking system · CPC title

• B60W2552/15

  Road slope, i.e. the inclination of a road segment in the longitudinal direction · CPC title

• B60W10/20

  including control of steering systems · CPC title

• B60W10/06 Primary

  including control of combustion engines · CPC title