Granted Patent B2

US 10,140,862 · App. 15/993,417 · Granted Nov 27, 2018

Abstract

Claims (66)

1. A system comprising:

a processor operable in a vehicle, the processor including or coupled to a memory to execute non-transient, machine-readable instructions stored in the memory to implement a traffic signal state prediction process;

a first interface coupled to the processor for wireless data communications with a roadside controller;

a second interface coupled to the processor to communicate prediction data to an on-board network in the vehicle;

the roadside controller programmed to:

acquire call data and traffic signal state data from a target traffic signal controller over a time period to form historical data;

calculate and store short-term statistical data associated with the target traffic signal controller based on the historical data; and

calculate and store long-term statistical data associated with the target traffic signal controller based on the historical data;

and wherein the in-vehicle processor is programmed to:

send a message to the roadside controller when the vehicle is near or approaching the target traffic signal;

receive the short-term and long-term statistical data from the roadside controller in response to the message;

input the received short-term and long-term statistical data to the traffic signal state prediction process;

executing the traffic signal state prediction process utilizing the short-term and long-term statistical data;

while the traffic signal state prediction process is executing, determining a current state of the target traffic signal by at least one of receiving a short-range broadcast message via the first interface, or receiving image data from a camera in the vehicle and determining the current state of the target traffic signal based on the received image data; and

in the traffic signal state prediction process:

updating a state of the traffic signal state prediction process to match the current state of the target traffic signal;

fast forwarding the traffic signal state prediction process from a current time state, based on the received statistical data, and terminate the traffic signal state prediction process at a future time state;

generate a prediction of future signal state of the target traffic signal at the future time state; and

transmit the prediction over the second interface to the on-board network in the vehicle for display in the vehicle or input to engine control units or other on-board computers for controlling operation of the vehicle.

2. The system of claim 1 including an electronic display in the vehicle, wherein the electronic display is coupled to the on-board network to display information based on the prediction.

3. The system of claim 1 wherein the short-range broadcast message comprises a Dedicated Short-Range Communications system (DSRC) compliant message.

4. The system of claim 1 wherein the camera is built into the vehicle.

5. A vehicle comprising:

a processor coupled to a memory to execute non-transient, machine-readable instructions stored in the memory, the stored instructions including instructions to implement a signal state prediction process;

a first interface coupled to the processor for wireless data communications;

a camera coupled to the processor for capturing image data including an image of a target traffic signal located in front of the vehicle;

the stored instructions configured to cause the processor to;

when the vehicle is approaching or near a traffic signal, send a request message including information to identify the traffic signal as a target traffic signal;

receive a reply message, the reply message including statistical data based on historical operation of the target traffic signal;

input the statistical data to the signal state prediction process;

begin executing the signal state prediction process, starting at a last sync point for the target traffic signal, and informed by the statistical data, advance the signal state prediction process to catch up to a current real-world time by clocking it at a clock rate faster than real-world time, so that at the current time a field traffic signal controller (FSC) associated with the target traffic signal and the signal state prediction process running in the vehicle are synchronized to the same state;

process image data captured by the camera to determine a current state of the target traffic signal;

input the current state of the target traffic signal to the signal state prediction process;

in the signal state prediction process, update a state of the target traffic signal to match the current state of the target traffic signal;

in the signal state prediction process, generate a prediction of a next state change of the target traffic signal in the future, by:

fast forwarding the signal state prediction process from the current state to a selected future time state, by clocking the signal state prediction process at a clock rate faster than real-world time,

generate prediction data comprising a prediction of a future state of the target traffic signal based on the future time state of the signal state prediction process; and

transmit the prediction data to an on-board network for display in the vehicle or input to engine control units or other on-board computers for controlling operation of the vehicle.

6. The vehicle of claim 5 wherein the stored instructions are further configured to cause the processor to:

generate a warning message based on the prediction data; and

transmit the warning message for display in the vehicle.

7. The vehicle of claim 5 wherein the stored instructions are further configured to cause the processor to:

generate an audio warning message based on the prediction data; and

transmit the audio warning message to be played over an audio output in the vehicle.

8. The vehicle of claim 5 wherein the stored instructions are further configured to cause the processor to store the prediction data in a data store.

9. The vehicle of claim 5 wherein the statistical data includes:

an observed maximum green signal duration, MAX_g_obs; and

for each second in a set [0, MAX_g_obs] in each phase, an empirical probability p for vehicle arrival/presence.

10. A method in a roadside traffic node comprising:

acquiring and storing call data and traffic signal state data from a target traffic signal controller over a time period to form historical data;

calculating and storing short-term statistical data associated with the target traffic signal controller based on the historical data; and

calculating and storing long-term statistical data associated with the target traffic signal controller based on the historical data;

receiving a message from a processor disposed in a vehicle when the vehicle is near or approaching the target traffic signal;

transmitting the short-term and long-term statistical data from the roadside traffic node in response to the message;

in the vehicle processor, receiving the short-term and long-term statistical data transmitted from the roadside traffic node and inputting the received short-term and long-term statistical data to a signal state prediction process;

in the vehicle processor, executing the signal state prediction process utilizing the short-term and long-term statistical data;

while the signal state prediction process is executing in the vehicle processor, determining a current state of the target traffic signal by at least one of receiving real-time state information from the roadside traffic node or receiving image data from a camera in the vehicle and determining the current state of the target traffic signal based on the received image data;

and

in the signal state prediction process:

updating a state of the signal state prediction process to match the current state of the target traffic signal; and

fast forwarding the signal state prediction process from a current time state to a future time state, based on the received statistical data;

in the vehicle processor, generating a prediction of a future signal state of the target traffic signal based on the future time state of the signal state prediction process; and

transmitting the prediction to an on-board network in the vehicle for display in the vehicle or input to engine control units or other on-board computers for use in controlling operation of the vehicle.

11. The method of claim 10 wherein the prediction includes an indication of the predicted signal status and a predicted time interval remaining until the target traffic signal controller changes state to the predicted signal status.

12. The method of claim 10 wherein receiving real-time state information from the roadside traffic node comprises receiving a short-range broadcast message from the roadside traffic node.

13. The method of claim 12 wherein the short-range broadcast message comprises a Dedicated Short-Range Communications system (DSRC) compliant message.

Assignments (8)