SYSTEMS AND METHODS OF WARNING APPROACHING VEHICLES OF AN AUTONOMOUS VEHICLE

1 . A method of warning approaching vehicles of an autonomous vehicle, the method comprising:

receiving one or more sensor signals from one or more vehicle sensors on the autonomous vehicle;

determining a stopped condition of the autonomous vehicle based on the one or more sensor signals; and

activating one or more warning indicators on a warning indicator device based on the stopped condition, the warning indicator device being mounted on the autonomous vehicle.

2 . The method of claim 1 , wherein the warning indicator device is mounted on the autonomous vehicle to display the one or more warning indicators rearward of the autonomous vehicle.

3 . The method of claim 2 , wherein the warning indicator device is mounted on a trailer of the autonomous vehicle.

4 . The method of claim 3 , wherein the warning indicator device is mounted to at least one of one or more vertical rear guardrails of the trailer or one or more horizontal rear guardrails of the trailer.

5 . The method of claim 1 , further comprising stopping the autonomous vehicle prior to activating the one or more warning indicators.

6 . The method of claim 5 , further comprising receiving an emergency signal prior to stopping the autonomous vehicle.

7 . The method of claim 1 , further comprising determining a location of the approaching vehicles with respect to the autonomous vehicle based on the one or more sensor signals.

8 . The method of claim 7 , further comprising selectively activating the one or more warning indicators based on the location of the approaching vehicles with respect to the autonomous vehicle.

9 . The method of claim 8 , further comprising selectively activating one or more first warning indicators of the one or more warning indicators including a first directional indicator if the approaching vehicles are on a first side of the autonomous vehicle.

10 . The method of claim 9 , wherein the one or more first warning indicators are right directional indicators.

11 . The method of claim 9 , further comprising selectively activating one or more second warning indicators of the one or more warning indicators including a second directional indicator if the approaching vehicles are on a second side of the autonomous vehicle.

12 . The method of claim 11 , further comprising selectively activating both the one or more first warning indicators and the one or more second warning indicators if the approaching vehicles are on both the first side and the second side of the autonomous vehicle.

13 . The method of claim 11 , wherein the one or more second warning indicators are left directional indicators.

14 . The method of claim 7 , further comprising activating a secondary warning indicator based on the location of the approaching vehicles with respect to the autonomous vehicle.

15 . The method of claim 14 , wherein the secondary warning indicator includes changing the one or more warning indicators from a first state to a second state.

16 . The method of claim 15 , wherein the second state includes at least one of a different pattern of the one or more warning indicators, a different color of the one or more warning indicators, a different size of the one or more warning indicators, a different frequency of the one or more warning indicators, or a different intensity of light emitted by the one or more warning indicators with respect to the first state.

17 . The method of claim 14 , wherein activating the secondary warning indicator comprises activating the second warning indicator based on a distance of the approaching vehicles to the autonomous vehicle.

18 . The method of claim 1 , wherein the warning indicator device includes a light bar, and the one or more warning indicators include one or more warning lights on the light bar.

19 . The method of claim 1 , further comprising deactivating the one or more warning indicators.

20 . The method of claim 1 , wherein activating the one or more warning indicators comprises causing the one or more warning indicators to progressively flash, to flash between on and off, to flash between different colors, to be constantly on, or any combination thereof.