Road signal systems and methods for controlling road signals include a piezoelectric layer integrated with a surface that undergoes stresses with traffic passing over the surface. A power collection circuit is configured to collect and store power from the piezoelectric layer. One or more devices receive electrical power from the power collection circuit responsive to traffic passing over the surface.

Road signal systems and methods for controlling road signals include a piezoelectric layer integrated with a surface that undergoes stresses with traffic passing over the surface. A power collection circuit is configured to collect and store power from the piezoelectric layer. One or more devices receive electrical power from the power collection circuit responsive to traffic passing over the surface.

Retroreflective sheeting having a structured layer of cube corner elements and an at least one optically variable mark therein, and methods of making same.

Retroreflective sheeting having a structured layer of cube corner elements and an at least one optically variable mark therein, and methods of making same.

A safety trailer is shown including first and second platforms, at least one of said first and second platforms having an axle and wheels attached thereto; a plurality of interconnected wall sections positioned between and connected to the first and second platforms, the plurality of wall sections defining a protected work area on a side of the trailer; and wherein the trailer supports a ballast member, the ballast member being positioned near a first side of the trailer and the wall sections near a second, opposing side of the trailer, the ballast member offsetting, at least partially, a weight of the plurality of wall sections.

A portable, self-illuminating traffic sign having a sign head with two opposite sides. One side indicates a first traffic signal, and the other side indicates a second traffic signal. Light assemblies are attached to each side of the sign head. The light assemblies emit light that may match the predominant color of one of the sides of the sign head. A battery may be disposed in a pole that connects to the sign head. A handlegrip allows for the sign to be held and provides a switch to allow for the lights to be selectively turned on and off.

A portable, self-illuminating traffic sign having a sign head with two opposite sides. One side indicates a first traffic signal, and the other side indicates a second traffic signal. Light assemblies are attached to each side of the sign head. The light assemblies emit light that may match the predominant color of one of the sides of the sign head. A battery may be disposed in a pole that connects to the sign head. A handlegrip allows for the sign to be held and provides a switch to allow for the lights to be selectively turned on and off.

Retroreflective sheeting having a structured layer of cube corner elements and an at least one optically variable mark therein, and methods of making same.

Retroreflective sheeting having a structured layer of cube corner elements and an at least one optically variable mark therein, and methods of making same.

Retroreflective articles comprise a substrate and a bar code provided on the substrate. The bar code comprises at least one human-readable information which provides framing information and a machine-readable information which provides variable information. The human-readable information is visible under a first condition and invisible under a second condition, and the machine-readable information is invisible under the first condition and visible under the second condition.