Non-selfish traffic lights passing advisory systems
Methods, vehicles and systems for managing vehicle velocity along routes having traffic lights. The behavior of an individual vehicle is adjusted to account for surrounding vehicles to avoid inefficient outcomes across a group of vehicles. A vehicle is configured to determine the presence of other vehicles in a defined following distance, and uses the presence of such other vehicles to adjust its own travel strategy, with or without communication or coordination with, or control over, the other vehicles.
1. A vehicle controller for a first vehicle, comprising one or more sensors for sensing conditions outside of the first vehicle and a transceiver for communicating with an off-board communication system, the vehicle controller configured to:
determine whether a second vehicle that shares a planned travel path with the first vehicle and is trailing the first vehicle is within a following distance of the first vehicle;
if the second vehicle is within the following distance:
adopt a first traffic-light approach method;
model a second vehicle trajectory for the second vehicle relative to at least one upcoming traffic light in the planned travel path shared by the first vehicle and the second vehicle; and
calculate a first vehicle trajectory to allow the first vehicle and the second vehicle to pass the at least one upcoming traffic light using a same go-period of the at least one upcoming traffic light; and
if the second vehicle is not within the following distance, adopt a second traffic-light approach method; wherein the vehicle controller is configured to adopt the first traffic-light approach by performing the following:
the vehicle controller determines a first velocity profile for passing the at least one upcoming traffic light, the upcoming traffic light having go-periods and no-go periods, such that the upcoming traffic light is passed by the first vehicle during a first go-period;
the vehicle controller determines whether the first velocity profile would enable the second vehicle to pass the upcoming traffic light during the first go-period and, if so, the vehicle controller implements the first velocity profile to control velocity of the first vehicle to pass the upcoming traffic light during the first go-period; otherwise,
the vehicle controller determines whether a second velocity profile would enable the second vehicle to pass the upcoming traffic light during the first go-period and either:
if so, implementing the second velocity profile to control velocity of the first vehicle through the upcoming traffic light;
if not, implementing the first velocity profile to control the first vehicle through the upcoming traffic light.
2. The vehicle controller of claim 1 , wherein:
the vehicle controller determines the first velocity profile by performing a cost function minimizing routine for the first vehicle itself without considering the second vehicle; and
the vehicle controller determines the second velocity profile by performing a cost function minimizing routine for the first and second vehicles as a group.
3. The vehicle controller of claim 1 , wherein:
the transceiver is configured for obtaining data indicating when go periods and no-go periods are to occur;
if the second vehicle is within the following distance, the vehicle controller is configured to communicate with the second vehicle to obtain one or more second vehicle travel parameters; and
the first traffic-light approach method includes analyzing the second vehicle travel parameters to determine whether the first vehicle and second vehicle can pass the upcoming traffic light during the same go-period of the upcoming traffic light.
4. A vehicle control method operable by a vehicle controller comprising:
identifying, in a first vehicle controller for a first vehicle, presence of at least one following vehicle that shares as planned travel path with the first vehicle and is trailing the first vehicle within a following distance of the first vehicle;
modeling, in the first vehicle controller, a following vehicle trajectory for the at least one following vehicle relative to at least one upcoming traffic light in the planned travel path shared by the first vehicle and the at least one following vehicle;
assessing, in the first vehicle controller, a prediction horizon for the first vehicle and identifying a traffic light having go and no-go periods in the prediction horizon; and
selecting, by the first vehicle controller, a speed control strategy for the first vehicle relative to the identified traffic light in the prediction horizon to limit degradation of a travel metric of the at least one following vehicle without violating a constraint of the first vehicle; and
implementing the selected speed control strategy in the first vehicle controller and the second vehicle to pass the identified traffic light using the same first go-period of the at least one upcoming traffic light in the planned travel path shared by the first vehicle and the at least one following vehicle.
5. The vehicle control method of claim 4 wherein the method further comprises communicating the speed control strategy from the first vehicle to the at least one following vehicle.
6. The vehicle control method of claim 5 wherein the step of selecting a speed control strategy for the first vehicle is performed as follows:
the first vehicle controller calculating a first velocity profile for the first vehicle to pass the identified traffic light in the prediction horizon, the first velocity profile being calculated to minimize energy consumption of the first vehicle;
the first vehicle controller determining that the first velocity profile for the first vehicle would not allow the at least one following vehicle to pass the identified traffic light in the first go period;
the first vehicle controller calculating a second velocity profile which allows the at least one following vehicle to pass the identified traffic light in the first go period; and
the first vehicle controller applying control parameters associated with the second velocity profile as the selected speed control strategy.
7. The vehicle control method of claim 5 wherein the step of selecting a speed control strategy for the first vehicle is performed as follows:
the first vehicle controller calculating a first velocity profile for the first vehicle to pass the identified traffic light in the prediction horizon, the first velocity profile being calculated to minimize wear on one or more of brakes and tires of the first vehicle;
the first vehicle controller determining that the first velocity profile for the first vehicle would not allow the at least one following vehicle to pass the identified light in the first go period;
the first vehicle controller calculating a second velocity profile which allows the at least one following vehicle to pass the identified traffic light in the first go period; and
the first vehicle controller applying control parameters associated with the second velocity profile as the selected speed control strategy.
8. The vehicle control method of claim 4 , further comprising:
the first vehicle communicating a first velocity plan for the first vehicle to a first following vehicle;
the first vehicle receiving, responsive to the communicated first velocity plan, a requested modification to the first velocity plan from the first following vehicle;
the first vehicle controller determining the requested modification can be accommodated without degrading an optimized metric of the first vehicle that would result from use of the first velocity plan beyond a predetermined degradation threshold;
the first vehicle communicating acceptance of the requested modification to the first following vehicle; and
the first vehicle controller calculating and implementing a second velocity plan that accommodates the requested modification.
9. The vehicle control method of claim 4 , further comprising:
the first vehicle communicating a first velocity plan for the first vehicle to a first following vehicle;
the first vehicle receiving, responsive to the communicated first velocity plan, a requested modification to the first velocity plan from the first following vehicle;
the first vehicle controller determining the requested modification would violate the constraint of the first vehicle;
the first vehicle communicating rejection of the requested modification to the first following vehicle; and
the first vehicle controller implementing the first velocity plan.
10. A vehicle controller for a first vehicle, the first vehicle including a communication transceiver for communicating with at least one other vehicle, the vehicle controller configured to:
receive velocity profile data from a second vehicle which is ahead of the first vehicle in a shared planned path of the first vehicle and the second vehicle;
determine whether the received velocity profile data will negatively affect a travel metric of the first vehicle relative to at least one traffic light in the shared planned path;
communicate a request to the second vehicle to adjust the received velocity profile data to accommodate the first vehicle passing the at least one traffic light;
receive a response either accepting or rejecting the request to the second vehicle;
calculate and implement a first velocity profile for the first vehicle if the request is accepted to thereby control velocity of the first vehicle through the at least one traffic light, wherein the first velocity profile is configured to allow the first vehicle and the second vehicle to pass the at least one traffic light in the first go period; and
calculate and implement a second velocity profile for the first vehicle if the request is rejected to thereby control velocity of the first vehicle through the at least one traffic light.
11. The vehicle controller of claim 10 wherein the second velocity profile is configured to allow the first vehicle to pass the at least one traffic light in a second go period after the first go period.
12. The vehicle controller of claim 10 wherein the first and second velocity profiles are calculated to minimize energy consumption by the first vehicle.
13. The vehicle controller of claim 10 wherein the first and second velocity profiles are calculated to achieve an earliest time of arrival at a destination for the first vehicle.
14. The vehicle controller of claim 10 wherein the first and second velocity profiles are calculated to minimize wear of one or more subsystems or components of the first vehicle.