Facilitating vehicle driving and self-driving

Patent metadata

Field	Value
Publication number	US-9645577-B1
Application number	US-201615078143-A
Country	US
Kind code	B1
Filing date	Mar 23, 2016
Priority date	Mar 23, 2016
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

Among other things, an operation related to control of a vehicle is facilitated by actions that include the following. A finite set of candidate trajectories of the vehicle is generated that begin at a location of the vehicle as of a given time. The candidate trajectories are based on a state of the vehicle and on possible behaviors of the vehicle and of the environment as of the location of the vehicle and the given time. A putative optimal trajectory is selected from among the candidate trajectories based on costs associated with the candidate trajectories. The costs include costs associated with violations of rules of operation of the vehicle. The selected putative optimal trajectory is used to facilitate the operation related to control of the vehicle.

First claim

The invention claimed is:

1. A method comprising
autonomously driving a vehicle within an environment to a destination by actions that include:
generating a finite set of candidate trajectories of the vehicle that begin at a location of the vehicle as of a given time, the candidate trajectories each being based on a sequence of world states at successive times and on transitions between successive states of the sequence, each of the world states comprising a state of the vehicle and a state of the environment as of the location of the vehicle and the corresponding time, the state of the environment comprising states of at least one of another vehicle, a cyclist, a pedestrian, or another obstacle,
selecting a putative optimal trajectory from among the candidate trajectories based on costs associated with the candidate trajectories, including costs associated with violations of rules of operation of the vehicle, the costs associated with a given trajectory being evaluated based on costs associated with sequences of two or more of the transitions between successive states of the trajectory, and
based on the selected putative optimal trajectory, commanding actuators of the vehicle to engage in control actions to drive the vehicle autonomously within the environment toward the destination.

2. The method of claim 1 in which the facilitating of the operation related to control of the vehicle comprises applying a feedback control policy associated with the putative optimal trajectory to control elements of the vehicle the application of the feedback control policy being based on the states of the vehicle and of the environment.

3. The method of claim 1 comprising applying one or more constraints to the finite set of candidate trajectories, the constraints being applied based on the sequence of world states at the successive times.

4. The method of claim 3 in which applying one or more constraints comprises attributing labels to each of the candidate trajectories of the finite set, each of the labels comprising a logical predicate that represent a property of the vehicle based on the candidate trajectory.

5. The method of claim 1 in which the putative optimal trajectory is associated with both speed and direction of the vehicle and selecting the putative optimal trajectory comprises determining a minimum-cost path through a directed graph of which the candidate trajectories comprise edges, the cost of the minimum-cost path comprising a penalty associated with violation of a constraint.

6. The method of claim 1 in which generating a finite set of candidate trajectories of the vehicle comprises applying a model that represents the vehicle's expected response to a given control policy as of the location of the vehicle and the given time, the model representing responses of elements of the environment to the given control policy and the vehicle's expected response as of the location of elements of the environment vehicle.

7. The method of claim 1 in which the costs associated with a given trajectory are based on costs associated with interactions between the states of the vehicle and the states of the environment and the costs are expressed as cost rules in a formal language that enables expression of the cost rules that are interpreted over sequences of two or more world states of a trajectory over time.

8. A method comprising
evaluating driving performance for a vehicle being driven within an environment to a destination, by actions that include:
generating a finite set of candidate trajectories of the vehicle that begin at a location of the vehicle as of a given time, the candidate trajectories each being based on a sequence of world states at successive times and on transitions between successive states of the sequence, each of the world states comprising a state of the vehicle and a state of the environment as of the location of the vehicle and the corresponding time, the environment comprising at least one of another vehicle, pedestrians, cyclists, or other obstacle,
selecting a putative optimal trajectory from among the candidate trajectories based on costs associated with the candidate trajectories, including costs associated with violations of rules of operation of the vehicle, the candidate trajectories taking account of locations of elements of the environment,
monitoring an actual trajectory of the vehicle for a given time period, and
comparing the actual trajectory of the vehicle with the putative optimal trajectory as an indication of the driving performance.

9. The method of claim 8 in which the driving performance comprises a human driver's performance.

10. The method of claim 9 comprising evaluating the driver's performance based on one or more performance metrics.

11. The method of claim 9 comprising displaying information related to the driver's performance on an in-vehicle display.

12. The method of claim 9 comprising transmitting information related to the driver's performance wirelessly to a receiver remote from the vehicle.

13. The method of claim 1 in which the facilitating an operation related to control of a vehicle comprises autonomously driving the vehicle.

14. A method comprising
autonomously driving a vehicle within an environment to a destination by actions that include:
generating a finite set of candidate trajectories of the vehicle as of a given time, the finite set of candidate trajectories belonging to a trajectory space of all possible trajectories of the vehicle,
assessing costs of each of the candidate trajectories, the costs comprising one or more of the following: length, turning angle, or other geometry related costs; acceleration, jerk, control effort, or other dynamic costs; and rule or constraint violations or other logical costs, the costs comprising a total order, and the putative optimal trajectory is selected as one with minimum cost according to the total order,
selecting a putative optimal trajectory from among the candidate trajectories of the finite set based on costs associated with the candidate trajectories, the selected putative optimal trajectory is associated with both speed and direction of the vehicle,
the space of all possible trajectories of the vehicle being sufficiently covered by the generated finite set of candidate trajectories so that the putative optimal trajectory comprises an arbitrarily close approximation to an actual optimal trajectory, and
based on the selected putative optimal trajectory commanding actuators of the vehicle to engage in control actions to drive the vehicle within the environment toward the destination.

15. The method of claim 14 comprising applying one or more constraints to the finite set of candidate trajectories.

16. The method of claim 14 comprising representing the candidate trajectories as edges of a directed graph.

17. The method of claim 14 in which the environment comprises a vehicle.

18. The method of claim 14 in which generating a finite set of candidate trajectories of the vehicle comprises applying a model that represents the vehicle's and the environment's expected response to a given control policy as of the location of the vehicle and a given time.

19. The method of claim 18 in which the control policy comprises a feedback function that determines commands to control the vehicle.

20. A method comprising
evaluating driving performance for a vehicle being driven within an environment to a destination, by actions that include:
generating a finite set of candidate trajectories of the vehicle as of a given

Assignees

• Nutonomy Inc

Inventors

• Frazzoli Emilio
• Iagnemma Karl

Classifications

• B60W2554/4026

  Cycles · CPC title

• B60W2554/4029

  Pedestrians · CPC title

• B60W2552/00

  Input parameters relating to infrastructure · CPC title

• B60W60/0015

  specially adapted for safety · CPC title

• B60W60/0011

  involving control alternatives for a single driving scenario, e.g. planning several paths to avoid obstacles · CPC title