A portable speed bump disc which can be easily deployed and removed from the roadway to control the speed of traffic. The disc preferably does not require mechanical and or chemical attachment to the pavement, and a plurality of discs, when placed in a staggered array on the roadway, can improve the safety of crews working in flagging operations, traffic work zones, or other situations where daily installation and removal of roadway warning devices may be required. Each disc is relatively small and light in weight as compared to conventional elongated rumble strips or speed bumps, and can be handled and deployed by a single worker.

This invention relates to a selective tire-impairment device attachable to a roadway surface. The device can include a lateral surface having a piercing element. The piercing element can be oriented downward to selectively impair a sidewall of a tire traveling laterally without affecting a tire traveling in a typical forward direction. The piercing element can severely damage a tire of a vehicle performing a stunt, commonly referred to as a doughnut, due to the lateral direction of travel of a tire during the stunt.

A driveway reflector holder and installation tool assembly includes a reflector holder and an installation tool removably receivable in the reflector holder. The reflector holder includes a hollow sleeve body, a washer disposed on an upper end of the hollow sleeve body, and at least one retention feature disposed on the hollow sleeve body. The installation tool includes an elongated body, a head, and a tapered tip. The installation tool is configured to extend through the hollow sleeve body of the reflector holder with the head being positioned above the upper end of the hollow sleeve body and the tapered tip being positioned below the lower end of the hollow sleeve body. The installation tool is configured to be driven to insert the at least one reflector holder into a ground surface and then be removed from the at least one reflector holder.

A driveway reflector holder and installation tool assembly includes a reflector holder and an installation tool removably receivable in the reflector holder. The reflector holder includes a hollow sleeve body, a washer disposed on an upper end of the hollow sleeve body, and at least one retention feature disposed on the hollow sleeve body. The installation tool includes an elongated body, a head, and a tapered tip. The installation tool is configured to extend through the hollow sleeve body of the reflector holder with the head being positioned above the upper end of the hollow sleeve body and the tapered tip being positioned below the lower end of the hollow sleeve body. The installation tool is configured to be driven to insert the at least one reflector holder into a ground surface and then be removed from the at least one reflector holder.

A road marker disclosed herein includes a single piece of material having a width of approximately three inches or less. The piece includes a top surface, a bottom surface, and a sloped face disposed between the top surface and the bottom surface. The bottom surface is configured to enable the bottom surface to be connected directly to a floor of a channel of a roadway. The road marker further includes a reflector disposed on the sloped face. Another road marker disclosed herein includes a reflecting member including a reflective surface. The road marker also includes a housing configured to support at least a portion of the reflecting member below a surface of a roadway.

A road marker disclosed herein includes a single piece of material having a width of approximately three inches or less. The piece includes a top surface, a bottom surface, and a sloped face disposed between the top surface and the bottom surface. The bottom surface is configured to enable the bottom surface to be connected directly to a floor of a channel of a roadway. The road marker further includes a reflector disposed on the sloped face. Another road marker disclosed herein includes a reflecting member including a reflective surface. The road marker also includes a housing configured to support at least a portion of the reflecting member below a surface of a roadway.

A road marker includes a single piece of material having a width of approximately three inches or less. The piece includes a top surface, a bottom surface, and a sloped face disposed between the top surface and the bottom surface. The bottom surface is configured to enable the bottom surface to be connected directly to a floor of a channel of a roadway. The road marker further includes a reflector disposed on the sloped face. Another road marker disclosed herein includes a reflecting member including a reflective surface. The road marker also includes a housing configured to support at least a portion of the reflecting member below a surface of a roadway.

A road marker includes a single piece of material having a width of approximately three inches or less. The piece includes a top surface, a bottom surface, and a sloped face disposed between the top surface and the bottom surface. The bottom surface is configured to enable the bottom surface to be connected directly to a floor of a channel of a roadway. The road marker further includes a reflector disposed on the sloped face. Another road marker disclosed herein includes a reflecting member including a reflective surface. The road marker also includes a housing configured to support at least a portion of the reflecting member below a surface of a roadway.

In an example, a method may read, at a first timestamp using a first reader device and a second reader device of a first vehicle, a first marker position from a first marker device located on a road segment at the first marker position and a second marker position from a second marker device located on the road segment at the second marker position that is different from the first marker position. The method may determine a vehicle position of the first vehicle on the road segment at the first timestamp based on the first marker position of the first marker device and the second marker position of the second marker device.

A road marker may include a housing with a cavity and at least one perimeter surface oriented perpendicular to the direction of traffic. Each of the at least two perimeter surfaces containing an opening may be substantially covered with a mesh. Further, each of the openings may form either an air input or an air output, and the air input and air output openings may be located substantially opposite to each other to generate a flow of air through the cavity. In addition, the cavity may include passive electrical components for heating the flow of air.