Abstract: A train equipped with an onboard system for determining its position and a track database for determining the positions of upcoming grade crossings sends activate after expiration messages to control wayside warning systems at the crossings to achieve a constant warning time while maintaining a safety margin that ensures the train can be stopped if the wayside systems do not respond correctly to the activate after expiration messages. The system may be used in place of existing track-based crossing warning system control circuits. Communications between the train may be radio-based, and may be direct between the train and wayside devices or may be routed through a central station, which may act as a relay or maintain a database. The train may control multiple crossings at one time, thereby eliminating the need for downstream adjacent crossing control.

Abstract: A flashing beacon may include a signal unit, a control unit associated with the signal unit, a solar panel or collector, and an activation device that may all be mounted or otherwise positioned on a post of a roadway sign. Light units associated with the signal unit may be programmed to flash on and off in a unique wig-wag pattern. Further, a light bar may also be used with the beacon to generate an intense flash of light soon after activation of the beacon as an additional means of grabbing the attention of the operator of a vehicle.

Abstract: A method and an apparatus control railway safety systems, in particular train routing systems and railway crossing systems. In order to simplify the railway line infrastructure while increasing the safety level at the same time, it is provided that the vehicle emits an RFID—radio frequency identification—signal which contains vehicle data and is read and evaluated by a device on the railway line in order to generate control input variables.

Abstract: There is provided a track current suppression device. An exemplary device includes an input coupled between rails of a railway track and configured to receive an input voltage corresponding to a track current. The exemplary device also includes an amplifier configured to receive the input voltage and generate a cancellation current. The exemplary device also includes an output coupled between the rails of the railway track and configured to deliver the cancellation current to the rails with reversed polarity compared to the track current.

Abstract: A flashing beacon may include a signal unit, a control unit associated with the signal unit, a solar panel or collector, and an activation device that may all be mounted or otherwise positioned on a post of a roadway sign. Light units associated with the signal unit may be programmed to flash on and off in a unique wig-wag pattern. Further, a light bar may also be used with the beacon to generate an intense flash of light soon after activation of the beacon as an additional means of grabbing the attention of the operator of a vehicle.

Abstract: A monitoring system and method is provided for monitoring the lighting and the gate arm position at a railroad crossing.

Abstract: An apparatus that indicates the speed of oncoming trains at train crossings comprises a large digital display attached to a drop gate or alternately on a side gate crossing sign for those crossings without a gate. The digital display is surrounded by a large sign indicating the speed of an oncoming train. A speed detection device aimed in either direction on the track to determine train speed. An interface converts the detected speed into a digital display. It is envisioned that motorists knowing the speed of an oncoming train will be less likely to try to beat the train through the crossing.

Abstract: A railroad crossing gate flasher assembly has a sealed, rodent-proof connection for electrical cables that pass from the foundation to a junction box. A clearance between the bottom of the junction box and the top of the foundation is sealed with a plate to prevent rodents from accessing the cables. The seal plate is mounted to the bolts that extend from the foundation and is leveled after it is inserted onto the bolts. The junction box is lowered onto the seal plate and attached to the same bolts so that the junction box also is level. The seal plate has an opening, coupling and conduit for protecting the cables.

Abstract: A system and method that enables trains to rapidly accelerate through grade crossings from station stops or civil speed restrictions is disclosed. In some embodiments, equipped trains and grade-crossing controllers communicate wirelessly to address operational limitations pertaining to the grade crossings. In conjunction with the train's equipment, conventional crossing controllers are augmented with a communications capability and logic to accept commands to operate in a “Prediction” mode or a “Motion-Sensing” mode. The Prediction mode is the default operating mode for conventional constant-warning grade-crossing prediction controllers. The Motion-Sensing mode is an operating mode whereby the crossing is actuated as soon as an approach circuit detects train motion.

Abstract: An autonomous vehicle collision/crossing warning system provides for simple, inexpensive and decentralized installation, operation and maintenance of a reliable vehicle collision/crossing warning system. The autonomous warning system preferably utilizes a single frequency TDM radio communication network with GPS clock synchronization, time slot arbitration and connectionless UDP protocol to broadcast messages among vehicles and components in the warning system. Adaptive localized mapping of components of interest within the warning system eliminates the need for centralized databases or coordination and control systems and enables new vehicles and warning systems to be easily added to the system in a decentralized manner. Preferably, stationary warning systems are deployed as multiple self-powered units each equipped to receive broadcast messages and to communicate with the other units by a low power RF channel in a redundant Master-Slave configuration.

Abstract: In a railroad crossing warning system having an electronic transmitter located on a first side of a road crossing connected across both railway rails, a first electronic receiver on the first side of the road crossing connected across both railway rails, a second electronic receiver on the second side of the road crossing connected across both railway rails, a method for determining direction a vehicle is traveling, the method including monitoring a voltage profile from at least one of the first receiver and the second receiver, as a vehicle moves along the railway rails towards the road crossing, and determining a direction the vehicle is moving based on the voltage profile.

Abstract: Apparatus, methods and a communication system for providing relatively constant warning time at a rail grade crossing for trains with prediction of the approach of a train from a remote controller via rail-based communications to a crossing controller. A first communication signal is generated when a prediction occurs and a second communication signal is generated for slower moving trains, with the second signal temporarily overriding the first signal to provide relatively constant warning time at the crossing. Cancellation timers with timing intervals are used to resolve situations where the train does not enter the approach or where the train leaves by way of a switch or backs out. Directional logic is used to determine the direction of movement of the train and, in conjunction with cancellation timers, causes the warning devices to be activated when the timers expire.

Abstract: A system and method that enables trains to rapidly accelerate through grade crossings from station stops or civil speed restrictions is disclosed. In some embodiments, equipped trains and grade-crossing controllers communicate wirelessly to address operational limitations pertaining to the grade crossings. In conjunction with the train's equipment, conventional crossing controllers are augmented with a communications capability and logic to accept commands to operate in a “Prediction” mode or a “Motion-Sensing” mode. The Prediction mode is the default operating mode for conventional constant-warning grade-crossing prediction controllers. The Motion-Sensing mode is an operating mode whereby the crossing is actuated as soon as an approach circuit detects train motion.

Abstract: A system is provided for sensing misalignment of a railroad signaling system. The railroad signaling system includes at least one railroad signal coupled to at least one elongated member adjacent to a railroad. The system includes at least one transmitter positioned within at least one elongated member, and at least one receiver positioned from each of said at least one transmitter within at least one adjacent elongated member to the at least one elongated member. More particularly, the system includes at least one electronic device coupled to each of a transmitter and each of at least one receiver, to sense detection of each transmitter by at least one receiver of at least one receiver indicative of misalignment of the railroad signaling system.

Abstract: An electronic controller for a highway-railroad grade crossing warning system is coupled to an approach circuit and to an island circuit and activates a warning device when a train is present in either of the approach or the island circuits. The controller has a display with touch-sensitive fields for selectively taking the approach circuit or island circuit out of service. Additional touch-sensitive fields on the display may be used for selecting the amount of time that the approach or island circuits remain out of service and for confirming that the maintainer wishes to take the these circuits out of service. Service is automatically restored upon expiration of the selected amount of time.

Abstract: A vital programmable logic device (VPD) is provided having at least two microprocessors. The VPD is configured to provide failsafe operation of a vital control system while operating in a closed circuit environment. In at least one embodiment of the present invention, railroad grade crossing signals are controlled by the VPD.

Abstract: A retractable gate comprising a movable arm gate having multiple sections which nest or telescope into each other when parked (e.g. upright), and extends into a full length blocking position as it is deployed. The gate arm sections are deployed by the movement of one of the arms, e.g. the outer one section, relative to the ground or a stationary support member and is joined to the stationary support member by a pivot point or bearing, and is connected to the stationary support or ground by a cable connection (or equivalent) which powers the arm sections into extended or retracted positions by movement of the gate about the pivot bearing. A novel corresponding counterweight system provides selectable balance and torque requirements.

Abstract: Systems and/or methods for reducing problems associated with the train/railroad systems are provided. In certain example embodiments, a system and/or method is provided wherein a sensor monitors a particular area (e.g. a train/railroad crossing, a tunnel entrance or exit, etc.) and transmits data (e.g. an image and/or video) to a train as it approaches the monitored area (e.g. when it is within a predetermined distance of the monitored area). In certain example embodiments, the sensor may be enclosed within a housing to prevent damage thereto. A display within the train may indicate whether or not there is a problem at the particular monitored area (e.g. a blockage at a crossing, a cave-in at a tunnel, etc.). Multiple images corresponding to multiple areas may be displayed, and may be ordered, for example, to the train. The conductor of the train may take appropriate action to avoid accidents and/or to reduce the impact of inevitable accidents (e.g., by stopping the train or reducing speed).

Abstract: A railroad crossing gate drive mechanism has an adjustable gate arm support in the form of a split hub mounted on the external portion of a drive shaft. A fixed section of the split hub is keyed to the drive shaft and has threaded bolt holes therein. A moveable section of the split hub mounts a gate arm connector and has arcuate slots cut on the same bolt circle as the fixed section's bolt holes. Cap screws extend through the arcuate slots and into the bolt holes. The horizontal position of the gate arm connector can be adjusted due to the loose fit afforded by the arcuate slots on the cap screws. When the gate arm connector is located in the desired horizontal position, the cap screws are tightened to lock the split hub sections together.

Abstract: An electronically controlled grade crossing gate system and method. The system includes a gate arm, a gate arm moving assembly, a position sensor assembly and a controller. The gate arm moving assembly is configured to move the gate arm and the position sensor assembly is configured to sense a position of the gate arm. The position sensor assembly is a non-contact position sensor assembly. The controller is coupled to the gate arm moving assembly and the position sensor assembly and it is configured to receive an incoming command related to the gate arm. The controller activates the gate arm moving assembly in response to the incoming command and communicates with the position sensor assembly to monitor the position of the gate arm.

Abstract: The present invention is directed to a train detection system for detecting the velocity, presence, and direction of a railroad car which may be utilized in existing railroad crossing installations. The train detection system is suitable for self-testing of its components and if an anomaly has been detected, the train detection system is capable of placing the system in a fail-safe state. The train detection system of the present invention is also capable of constant communication between the sensor of said system and the implementing device of the train detection system via a wireless link.

Abstract: A railroad crossing gate with a gate assembly. An extendible member slides within an outer member with minimal friction. When the gate is in its open position, gravity retracts the extendible member to hollow member. When the gate is in its blocking position, gravity causes the extendible member to move out of the hollow member to a final blocking position.

Abstract: A vehicle contained warning system and method for warning the occupants of a motor vehicle approaching a railway grade crossing at which there is installed a railway grade crossing warning system including such as warning lights and a crossing gate wherein a radio frequency transmitter radiates selected signals responsive to information stored in the crossing analyzer of the railway grade crossing warning system. Upon approach of a train, the grade crossing warning system begins transmitting an encoded signal including such as information on the approach of the train and what of any of the functional aspects of the warning system may be non operational such as the warning lights, and the crossing gate. The receiver in the vehicle within the range of the transmitter decodes the received signal and activates the contained alarms to alert the occupants (particularly the driver) of the vehicle of the approaching train and the condition of the warning system.

Abstract: A railroad crossing gate is repaired by lowering the crossing gate mechanism with a lever. The end of the lever can contain a conical opening mating with the conical pivot pin on the gate mechanism.

Abstract: A gate system for an intersection of a railroad track and roadway has detectors to monitor the intersection and crossing relays to monitor the railroad track. A controller connected to the detectors and the crossing relays operates the gates to prevent the gates from trapping a vehicle on the tracks.

Abstract: A railroad grade crossing warning device designed to operate at un-guarded grade crossings without the need for expensive train detection sensors. The system utilizes the sound of an approaching locomotive horn or whistle to activate a warning at a grade crossing. The preferred device is self contained and is powered by solar panel and storage battery to provide a flashing strobe warning on the approach of a train.

Abstract: One embodiment of the present invention is a system for monitoring failure of a signal having lighting configured to indicate a predetermined alarm condition. The system includes a detector/transmitter responsive to lighting parameters at least during the predetermined alarm condition to generate a signal indicative of the lighting parameters; an attachment member configured to attach the detector/transmitter to a lamp socket of the lighting in an orientation in which the detector/transmitter assembly is responsive to light rays from a lamp mounted in the lamp socket when the lamp is on; and a receiver/concentrator responsive to the signal indicative of the lighting parameters to generate a signal indicative of predetermined fault conditions of the lighting.

Abstract: In one embodiment, the present invention is an alarm monitor for a railroad grade crossing, the grade crossing having an island activation relay that is activated in response to an approaching train, the alarm monitor including a micropower impulse radar (MIR) responsive to pedestrians and motor vehicles in a prohibited area of the crossing island during activations of the island activation relay; and a processor configured to generate a warning signal when the MIR detects a pedestrian or a motor vehicle in the prohibited area during an activation of the island activation relay.

Abstract: One embodiment of the present invention is a system for monitoring failure of a signal having lighting configured to indicate a predetermined alarm condition. The system includes a detector/transmitter responsive to lighting parameters at least during the predetermined alarm condition to generate a signal indicative of the lighting parameters; an attachment member configured to attach the detector/transmitter to a lamp socket of the lighting in an orientation in which the detector/transmitter assembly is responsive to light rays from a lamp mounted in the lamp socket when the lamp is on; and a receiver/concentrator responsive to the signal indicative of the lighting parameters to generate a signal indicative of predetermined fault conditions of the lighting.

Abstract: A device for monitoring the passage of a train traveling through a rail way crossing, said device including a first and second sensors for sensing the presence of the train on a rail track when the train is in proximity to the sensors, said first and second sensors positioned adjacent the track, first and second processors opperatively coupled to the first and second sensors, respectively, the processors adapted to monitor the sensors and determine the speed and direction of the train when the train passes the sensors. The device also includes a signal positioned adjacent the crossing for signaling the public that a train is about to enter the rail way crossing, and a third processor operatively coupled to the signal and operatively coupled to the first and second processors, the third processor adapted to activate the signal when the train is within a predetermined time interval from entering the crossing.

Abstract: To reduce or eliminate difficulties inherent in manual reporting of signal light failures, especially at remote railroad grade crossings, there is provided, in one embodiment of the present invention, a system for monitoring failure of a lighted signal that includes lighting configured to flash during a predetermined alarm condition. The system includes a power supply configured to power the lighting during the predetermined alarm condition and to provide a timing signal indicative of power being applied to the lighting; a detector/transmitter responsive to the timing signal to detect lighting parameters when the lighting is flashed on to generate a signal indicative of the lighting parameters and to generate a signal indicative of the lighting parameters; and a receiver/concentrator responsive to the signal indicative of the lighting parameters to generate a signal indicative of predetermined fault conditions of the lighting.

Abstract: A system and method which can detect the presence of a vehicle within the protected area of a four gate railroad crossing, determine its location and direction it is moving in, and open an appropriate exit gate to allow the vehicle to escape prior to the arrival of a train at the crossing. The system has a series of magnetometer sensors suitably placed in the crossing to detect the presence of a vehicle. The sensors are connected to a controller which analyzes readings from the sensors. Upon the approach of a train, the controller, based on analysis of readings from the sensor, determines if a vehicle has become entrapped and determines which exit gate must be opened or should remain open to allow the entrapped vehicle to escape. The system also has self test capabilities as well as the ability to continuously update, when no vehicles are present, a baseline reading of the ambient magnetic condition of the crossing area, which baseline the controller uses in analyzing data from the sensors.

Abstract: An apparatus that prevents motorists from crossing railroad tracks, when the warning gates are down during approaching of a train consists, of a plurality of tire-piercing cogs which are retracted from the ground when the railroad crossing gate is closed. The cogs are arranged across the entire width of the automobile road in order to prevent a motorist from going around the closed gate through the oncoming traffic lane. The piercing cogs are interlocked with a warning visual and/or sound signal which is activated if the vehicle went onto the railroad tracks and stuck on the rails after smashing the closed road gate arm. The cog drive mechanism is located below the ground level, and when the gate is open for normal traffic through the railroad crossing, the cogs are turned into position in which their back surfaces are arranged in flush with the ground level for smooth passage of the vehicles.

Abstract: A screw-threaded counterweight adjustment apparatus is journaled in end journals provided with brackets for attachment to the interior of a railroad crossing gate arm casing preferably by jam-type threaded fittings. A traveler is threaded over an elongated helically threaded rod rotatably mounted in the journals. A guide on one side of the traveler fits in an adjustment slot in the casing and a counterweight supporting rod or pin extends from the guide for attachment and support of the counterweights. The helically threaded rod is manually rotated by a wrench or by a motor to move the traveler and guide longitudinally on the counterweight section of the gate when it is desired to adjust the position of the counterweights.

Abstract: A railway gate system comprising a railway station having an elevated platform area for passengers to stand and a recessed area with a track and a train movable therealong. A gate has a continuous upper restraining rail along its length. A plurality of cylindrical posts each have an upper end secured to the lower surface of the rail and a lower end. A horizontal recess and vertical apertures are located in the edge of the platform area adjacent to the track. The recess is adapted to receive the rail when lowered to an inoperative orientation and with the circular apertures adapted to slidably receive the posts. Motion imparting mechanisms include elongated pistons having upper ends secured to the lower surface of the rail, central extents extending through selected spaced circular apertures in the platform and lower ends. Hollow cylinders are located beneath the selected spaced circular apertures having open upper ends to receive the pistons.

Abstract: A method and apparatus for determining the length of a train utilizing received signal such as a reference signal from a global positioning system or the like is disclosed. A first receiver receives a signal, such as a reference signal from a global positioning system or the like, from which a first position on a train may be determined. Similarly, a second receiver receives a signal from which a second position on the train may be determined. A processor, operatively coupled to the first and second receivers, determines the length of the train based on the first and second positions.

Abstract: An apparatus and method for improving the safety of railroad systems of the present invention includes a system for navigating a railroad vehicle over railroad tracks. An attitude sensor is used to dynamically sense the attitude of the railroad vehicle as it travels over a set of railroad tracks. By sensing the attitude of the railroad vehicle, a determination of the condition of the railroad tracks can be made. The apparatus also sensed the position of the railroad vehicle in real time to correlate the sensed attitude with a precise position along the railroad tracks. The navigation system is capable of determining a highly accurate position of the vehicle in real time. The position of the vehicle is also used to navigate the railroad vehicle.

Abstract: A railroad crossing traffic warning system for alerting a motorist approaching a railroad crossing to the presence of an oncoming train. The system comprises a series of magnetometer sensor probes buried in the right-of way adjacent to a railroad track at predetermined distances from the railroad crossing. These sensors provide a signal to a controller unit when the presence of a train is sensed. The controller unit first determines the speed at which the oncoming train is traveling and the time it will take for the train to reach the crossing and then activates an improved warning apparatus at a predetermined amount of time before the train reaches the crossing.

Abstract: With the vehicle anti-collision system of the present invention, road vehicles in the vicinity of a railway crossing are alerted as a train approaches the crossing. A signalling device operating in conjunction with a GPS receiver located in the train emits a signal to a receiver located at the railway crossing to provide an indication of the rail vehicle's location with respect to the railway crossing. The signal is sent continuously at predetermined intervals to provide the railway crossing with sufficient data to estimate the velocity and time of arrival of the train or railway vehicle at the crossing. The railway crossing processes the information and transmits an alarm signal to approaching road vehicles as the rail vehicle approaches the crossing. The signal emitted by the crossing is received at the road vehicle which provides various levels of alarms depending on how close the rail vehicle is to the crossing.

Abstract: A railroad-crossing warning system for protecting pedestrians and motorists from an oncoming train. The warning system has a vehicle detector system for determining whether a vehicle is stuck in an area of the railroad crossing, a train detector system for determining vital train information including the speed and direction of the oncoming train, a display unit for displaying warning messages to the pedestrians and motorists approaching the railroad crossing, and a communication system for communicating the vital train information and the distressed vehicle information to the oncoming train and the display system. The system provides early warning to the operator of the oncoming train to provide more reliable protection for distressed vehicles in the railroad crossing and for motorists and pedestrians approaching the railroad crossing.

Abstract: A railroad crossing gate electrical control system for moving a crossing gate in up and down directions also provides for raising the gate counterweights in a failure mode. The control system includes an electric motor having a plurality of electromagnet poles and an armature rotating inside of the poles, with armature movement controlling gate movement. There is a motor and snub relay having contacts connected to the armature and the motor poles. A terminal board has movable contacts which are connected to the motor and snub relay and to a relay coil for moving the contacts of the snub relay. A source of power is connected to the terminal board. The movable terminal board contacts control the application of power to the motor and snub relay coil and the motor and snub relay contacts for operating the motor to cause up and down gate movement. There is a maintenance relay having a coil connected through a normally open switch to the source of power.

Abstract: A railroad crossing gate electrical control system for moving a crossing gate in up and down directions and providing snubbing protection to gate movement in failure modes includes an electrical motor having two diametrically positioned permanent magnet poles and two series connected electromagnet poles. There is an armature which rotates inside of the poles. There is a motor and snub relay which has contacts connected to the armature and the series connected electromagnet poles. A terminal board has movable contacts which are connected to the motor and snub relay and to a relay coil for moving the contacts of the motor and snub relay. A source of power is connected to the terminal board, with the movable terminal board contacts controlling the application of power to the motor snub relay coil and the relay contacts for causing up and down movement and for providing snubbing of armature movement during up and down gate movement and gate failure modes.

Abstract: A highway crossing gate control circuit is provided which minimizes the "pumping" oscillation of a highway crossing gate arm which is driven up by a permanent magnet motor. A preferred embodiment of the control circuit utilizes a p-channel MOSFET in a power down module of the control circuit to restrict power from being applied to the motor when the gate arm is in an up position and is intended to be held in the up position by a hold clear device which acts as a mechanical break. Provision is included for dynamic braking on the gate arm moving downward after an initial drive down mode.

Abstract: A railroad crossing traffic warning system for alerting a motorist approaching a railroad crossing to the presence of an oncoming train. The system comprises a series of magnetometer sensor probes buried in the right-of way adjacent to a railroad track at predetermined distances from the railroad crossing. These sensors provide a signal to a controller unit when the presence of a train is sensed. The controller unit first determines the speed at which the oncoming train is traveling and the time it will take for the train to reach the crossing and then activates an improved warning apparatus at a predetermined amount of time before the train reaches the crossing.

Abstract: With the vehicle anti-collision system of the present invention, road vehicles in the vicinity of a railway crossing are alerted as a train approaches the crossing. A signalling device operating in conjunction with a GPS receiver located in the train emits a signal to a receiver located at the railway crossing to provide an indication of the rail vehicle's location with respect to the railway crossing. The signal is sent continuously at predetermined intervals to provide the railway crossing with sufficient data to estimate the velocity and time of arrival of the train or railway vehicle at the crossing. The railway crossing processes the information and transmits an alarm signal to approaching road vehicles as the rail vehicle approaches the crossing. The signal emitted by the crossing is received at the road vehicle which provides various levels of alarms depending on how close the rail vehicle is to the crossing.

Abstract: A train warning device has a ladder frame with barrier sign hingedly mounted for movement by an electric motor between positions folded against the frame between the tracks and upstanding transversely from the tracks. Releasable clamping arms are mounted at the top and bottom of ladder uprights for securement thereof to track ties and enabling passage of a train thereover when folded. A signal receiver/micro computer mounted on the ladder frame controls the motor operation in response to a signal received from a hand held remote controller. A battery mounted on the ladder frame supplies power to the electric motor, signal receiver and other devices such as lamps to ensure independent operation. The barrier sign is profiled as a flagman with a sprung warning arm carrying a stroboscopic lamp. The ladder frame can be used to access the track from an elevated platform.

Abstract: The present invention provides a signalling system for a railroad locomotive, providing the locomotive with the capability to signal its approach to upcoming railroad crossing signals in order for the crossing signals to activate lights, bells or similar warning devices. The present invention includes a global positioning system receiver mounted within the locomotive for the purpose of determining the train location and, therefore, its proximity to the known locations of railroad crossings. The present invention also includes a self-diagnostic mechanism within the crossing signal device capable of performing certain internal checks for proper functioning of the warning devices. Such information, along with a digitally encoded identification of the particular crossing, is relayed to the locomotive as it passes the crossing.

Abstract: A crossing lights controller for effecting operation of the crossing lights during normal train operating conditions and during a controller failure mode includes a train sensing input, a lights control circuit, a solid state logic and monitor circuit, an independent source of both AC and DC power, and a fail-safe relay. The train sensing input provides one signal condition when the approach of a train is sensed and another signal condition when no train is sensed. The lights control circuit has power supplied thereto to operate the lights in a flashing condition when the train sensing input indicates the approach of a train. The solid state logic and monitor circuit is connected to the input circuit and the lights control circuit and applies and removes power to the lights control circuit in accordance with signals at the input.

Abstract: A three-piece, compact wireless railroad grade crossing motorist warning device comprising: a locomotive mounted transceiver which simultaneously communicates (upon close proximity) with a similar transceiver mounted at railroad grade crossing, and motor vehicles equipped with sympathetic receivers. Upon signal receipt verification, the grade crossing transceiver emits a coded radio signal to local motoring public sympathetic receivers. Upon signal reception, an audio/visual alert is presented to the motor vehicle operator, alerting the motor vehicle operator to the locomotive-occupied railroad crossing. Additionally, a contact verification display is displayed to the operator of the locomotive, upon activation of the grade site transceiver.

Abstract: Warning lights at a railroad grade crossing are energized at a predetermined flash rate when a train is approaching through the use of an essentially fail-safe solid state crossing controller employing circuitry that is active in creating an off condition of the warning lamps. A controller unit operates a pair of warning lamps alternately in synchronism with a warning rate (flash rate) signal having a predetermined repetition rate, such as 55 pulses per minute. When the crossing is safe, an RC circuit in the lamp driver responds to a 500 Hz safe status signal by providing continuous control excitation to a normally conductive lamp switching circuit to maintain the lamps deenergized. In a failure mode, the normal condition of the switching circuit maintains one lamp of each pair continuously energized.