System delay estimation method for autonomous vehicle control

• US 10,227,075 B2
• Filed: 09/28/2016
• Issued: 03/12/2019
• Est. Priority Date: 09/28/2016
• Status: Active Grant

• Current Assignee: Baidu USA LLC (Baidu Incorporated)
• Original Assignee: Baidu USA LLC (Baidu Incorporated)
• Inventors: Zhu, Fan, Kong, Qi, Yang, Guang, Wang, Jingao
• Primary Examiner(s): Brushaber, Frederick M
• Application Number:
  US15/278,439
• Publication Number:
  US 20180086351A1
• Time in Patent Office: 895 Days
• CPC Class Codes: B60W 2050/0002 Automatic control, details of type of controller or control system architecture
• CPC Class Codes: B60W 2050/0022 Gains, weighting coefficients or weighting functions
• CPC Class Codes: B60W 2050/0075 Automatic parameter input, automatic initialising or calibrating means
• CPC Class Codes: B60W 30/10 Path keeping cruise control for automatically following a preceding vehicle B60W30/165
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle
• CPC Class Codes: B60W 50/06 Improving the dynamic response of the control system, e.g. improving the speed of regulation or avoiding hunting or overshoot
• CPC Class Codes: G05D 1/0212 with means for defining a desired trajectory involving a plurality of land vehicles G05D1/0287

Abstract

In one embodiment, a steering control delay is measured, where the steering delay represents the delay between the time of issuing a steering control command and the time of a response from one or more wheels of an autonomous vehicle. A speed control delay is measured between the time of issuing a speed control command and the time of a response from one or more wheels of the autonomous vehicle or the time of supplying pressure to the gas pedal or brake pedal. In response to a given route subsequently, an overall system delay is determined based on the steering control delay and the speed control delay using a predetermined algorithm. Planning and control data is generated in view of the system delay for operating the autonomous vehicle.

Claims

1. A computer-implemented method for operating an autonomous vehicle, the method comprising:

measuring a steering control delay between time of issuing a steering control command and time of a first response from one or more wheels of an autonomous vehicle;

measuring a speed control delay between time of issuing a speed control command and time of a second response from one or more wheels of the autonomous vehicle;

estimating an overall system delay based on the steering control delay and the speed control delay using a predetermined algorithm;

perceiving a driving environment surrounding the autonomous vehicle based on sensor data obtained from a plurality of sensors mounted on the autonomous vehicle at a given point in time;

planning a route to drive the autonomous vehicle along the route based on perception data of the driving environment;

generating planning and control data for the route, the planning and control data including information specifying a plurality of control commands to be issued at different points in time along the route;

modifying the planning and control data in view of the system delay, including modifying timing of at least one of the control commands; and

controlling the autonomous vehicle based on the modified planning and control data.

2. The method of claim 1, wherein the steering control delay is measured based on time between issuing the steering control command and positioning the one or more wheels in an angle specified by the steering control command.

3. The method of claim 1, wherein the speed control delay comprises an acceleration delay representing a difference between time of issuing an acceleration command and time the autonomous vehicle starts accelerating.

4. The method of claim 1, wherein the speed control delay comprises a deceleration delay representing a difference between time of issuing a braking command and time the autonomous vehicle starts decelerating.

5. The method of claim 1, wherein the predetermined algorithm is a weighted algorithm, and wherein each of the steering control delay and the speed control delay is assigned with a specific weight coefficient for a specific driving scenario.

6. The method of claim 5, wherein when the autonomous vehicle is to turn, a weight coefficient for the steering control delay is adjusted higher.

7. The method of claim 5, wherein when a difference between a current speed and a target speed of the autonomous vehicle becomes larger, a weight coefficient for the speed control delay is adjusted higher.

8. The method of claim 1, further comprising:

determining a computational delay representing time a control system of the autonomous vehicle takes to generate and issue a control command; and

determining a communication delay representing a time delay of transmitting a control command over a communication bus of the autonomous vehicle, wherein the system delay is estimated further based on the computational delay and the communication delay.

9. A non-transitory machine-readable medium having instructions stored therein, which when executed by a processor, cause the processor to perform operations of determining a system delay of an autonomous vehicle, the operations comprising:

measuring a steering control delay between time of issuing a steering control command and time of a first response from one or more wheels of an autonomous vehicle;

measuring a speed control delay between time of issuing a speed control command and time of a second response from one or more wheels of the autonomous vehicle;

estimating an overall system delay based on the steering control delay and the speed control delay using a predetermined algorithm;

perceiving a driving environment surrounding the autonomous vehicle based on sensor data obtained from a plurality of sensors mounted on the autonomous vehicle at a given point in time;

planning a route to drive the autonomous vehicle along the route based on perception data of the driving environment;

generating planning and control data for the route, the planning and control data including information specifying a plurality of control commands to be issued at different points in time along the route;

modifying the planning and control data in view of the system delay, including modifying timing of at least one of the control commands; and

controlling the autonomous vehicle based on the modified planning and control data.

10. The machine-readable medium of claim 9, wherein the steering control delay is measured based on time between issuing the steering control command and positioning the one or more wheels in an angle specified by the steering control command.

11. The machine-readable medium of claim 9, wherein the speed control delay comprises an acceleration delay representing a difference between time of issuing an acceleration command and time the autonomous vehicle starts accelerating.

12. The machine-readable medium of claim 9, wherein the speed control delay comprises a deceleration delay representing a difference between time of issuing a braking command and time the autonomous vehicle starts decelerating.

13. The machine-readable medium of claim 9, wherein the predetermined algorithm is a weighted algorithm, and wherein each of the steering control delay and the speed control delay is assigned with a specific weight coefficient for a specific driving scenario.

14. The machine-readable medium of claim 13, wherein when the autonomous vehicle is to turn, a weight coefficient for the steering control delay is adjusted higher.

15. The machine-readable medium of claim 13, wherein when a difference between a current speed and a target speed of the autonomous vehicle becomes larger, a weight coefficient for the speed control delay is adjusted higher.

16. The machine-readable medium of claim 9, wherein the operations further comprise:

determining a computational delay representing time a control system of the autonomous vehicle takes to generate and issue a control command; and

determining a communication delay representing a time delay of transmitting a control command over a communication bus of the autonomous vehicle, wherein the system delay is estimated further based on the computational delay and the communication delay.

17. 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 of determining a system delay of an autonomous vehicle, the operations including

measuring a steering control delay between time of issuing a steering control command and time of a first response from one or more wheels of an autonomous vehicle,

measuring a speed control delay between time of issuing a speed control command and time of a second response from one or more wheels of the autonomous vehicle,

estimating an overall system delay based on the steering control delay and the speed control delay using a predetermined algorithm,

perceiving a driving environment surrounding the autonomous vehicle based on sensor data obtained from a plurality of sensors mounted on the autonomous vehicle at a given point in time,

planning a route to drive the autonomous vehicle along the route based on perception data of the driving environment,

generating planning and control data for the route, the planning and control data including information specifying a plurality of control commands to be issued at different points in time along the route,

modifying the planning and control data in view of the system delay, including modifying timing of at least one of the control commands; and

controlling the autonomous vehicle based on the modified planning and control data.

18. The system of claim 17, wherein the steering control delay is measured based on time between issuing the steering control command and positioning the one or more wheels in an angle specified by the steering control command.

19. The system of claim 17, wherein the speed control delay comprises an acceleration delay representing a difference between time of issuing an acceleration command and time the autonomous vehicle starts accelerating.

20. The system of claim 17, wherein the speed control delay comprises a deceleration delay representing a difference between time of issuing a braking command and time the autonomous vehicle starts decelerating.

21. The system of claim 17, wherein the predetermined algorithm is a weighted algorithm, and wherein each of the steering control delay and the speed control delay is assigned with a specific weight coefficient for a specific driving scenario.

22. The system of claim 21, wherein when the autonomous vehicle is to turn, a weight coefficient for the steering control delay is adjusted higher.

23. The system of claim 21, wherein when a difference between a current speed and a target speed of the autonomous vehicle becomes larger, a weight coefficient for the speed control delay is adjusted higher.

24. The system of claim 17, wherein the operations further comprise:

determining a computational delay representing time a control system of the autonomous vehicle takes to generate and issue a control command; and

determining a communication delay representing a time delay of transmitting a control command over a communication bus of the autonomous vehicle, wherein the system delay is estimated further based on the computational delay and the communication delay.