Abstract: An SIL 4 over-speed protection device for a rail vehicle includes a first logical unit configured to be connected to a first power source, a first speed sensor and a first vital supervision circuit and a second logical unit configured to be connected to a second power source, a second speed sensor and a second vital supervision circuit. The first logical unit is configured to determine if the second logical unit is functioning properly and the second logical unit is configured to determine if the first logical unit is functioning properly.

Abstract: A circuit for controlling an input current, the circuit includes a first input port configured to receive the input current. A current detector detects an input current value of the input current and generates a control signal indicative of the input current value. A first output port outputs an output current to a load. A second output port receives the output current from the load. A control circuit provides a low-impedance path in parallel with the load in response to the control signal indicating the input current value is below a threshold value.

Abstract: A method of common controller area network (CAN) bus traffic supervision on a system having a common CAN bus, a first CAN chip and a second CAN chip, the first CAN chip and the second CAN chip are coupled together with the common CAN bus, the method includes comparing a first CAN frame received from the first CAN chip to a second CAN frame received from the second CAN chip within a CAN comparison period, and detecting a failure of at least the first CAN chip or the second CAN chip. Detecting the failure of at least the first CAN chip or the second CAN chip includes determining that the first CAN frame is not identical to the second CAN frame within the CAN comparison period.

Abstract: A method of common controller area network (CAN) bus traffic supervision on a system having a common CAN bus, a first CAN chip and a second CAN chip, the first CAN chip and the second CAN chip are coupled together with the common CAN bus, the method includes comparing a first CAN frame received from the first CAN chip to a second CAN frame received from the second CAN chip within a CAN comparison period, and detecting a failure of at least the first CAN chip or the second CAN chip. Detecting the failure of at least the first CAN chip or the second CAN chip includes determining that the first CAN frame is not identical to the second CAN frame within the CAN comparison period.

Abstract: An SIL 4 over-speed protection device for a rail vehicle includes a first logical unit configured to be connected to a first power source, a first speed sensor and a first vital supervision circuit and a second logical unit configured to be connected to a second power source, a second speed sensor and a second vital supervision circuit. The first logical unit is configured to determine if the second logical unit is functioning properly and the second logical unit is configured to determine if the first logical unit is functioning properly.

Abstract: A circuit for controlling an input current, the circuit includes a first input port configured to receive the input current. A current detector detects an input current value of the input current and generates a control signal indicative of the input current value. A first output port outputs an output current to a load. A second output port receives the output current from the load. A control circuit provides a low-impedance path in parallel with the load in response to the control signal indicating the input current value is below a threshold value.

Abstract: A system and method provide seamless control switchover through an input coupled to a power line and a safety apparatus that actuates if the input remains de-energized for a first time interval. Each of a plurality of subsystems has a control unit that controls a power source to energize the power line and is capable of transitioning between master and slave states. A first switch or second and third switches in series couple the power source to the power line. The first switch is closed during master state operation. The second switch is closed during slave operation and the third switch is open if any subsystem control unit is in master state. The system is configured to open or close the first switch, the second switch, or the third switch responsive to a transition of a control unit to or from master state within the first time interval.

Abstract: A system and method provide seamless control switchover through an input coupled to a power line and a safety apparatus that actuates if the input remains de-energized for a first time interval. Each of a plurality of subsystems has a control unit that controls a power source to energize the power line and is capable of transitioning between master and slave states. A first switch or second and third switches in series couple the power source to the power line. The first switch is closed during master state operation. The second switch is closed during slave operation and the third switch is open if any subsystem control unit is in master state. The system is configured to open or close the first switch, the second switch, or the third switch responsive to a transition of a control unit to or from master state within the first time interval.

Abstract: A system, method, and safety unit provide safety assurance for a multiple redundant system controlling a plant or complex. A unit active line (UAL) status indicates the presence of at least one redundant active unit within the system. A safety verification line (SVL) status verifies the powered down status of all redundant units not active within the system. A safety unit is associated with a vital supervision card (VSC) and vital power bus and the safety unit controls switchable connections from the vital power bus to the UAL and the SVL. Based on verification of UAL and SVL status, system control includes energizing the UAL.

Abstract: An apparatus that determines that a vehicle has moved comprises a shaft member, a pin configured to attach the shaft member to a backing plate via an opening in the shaft member that enables the shaft member to move in a direction along the length of the shaft member, to rotate about the pin, and to contact a surface external to the vehicle when the shaft member is in a first position. The apparatus also comprises a first alignment magnet that attracts the shaft member to the surface external to the vehicle and a first sensor that determines that the shaft member is in the first position. The apparatus further comprises a first holding magnet, a second holding magnet, and at least one sensor that indicates that the shaft member is in contact with the first holding magnet or the second holding magnet, each indicating a direction of movement.

Abstract: A system and method provide the capability to dynamically measure the diameter of a train wheel. An onboard sensor signals detection and loss of detection of a proximity plate having a predetermined length and placed along a direction of travel of the train. A signal generator generates a signal indicating the number of revolutions of the wheel. Based on the sensor signals indicating detection and loss of detection of the proximity plate, the length of the proximity plate, and the corresponding number of wheel revolutions, a controller automatically calculates the wheel diameter.

Abstract: An apparatus for detecting the information about a guideway-guided vehicle having a masking component, the guideway-guided vehicle configured to follow a path of a guideway, comprising a radio frequency identification (RFID) system, method of making, and use thereof are disclosed. The RFID system comprises a first RFID transponder for transmitting, across the path, first RFID transponder specific information. An RFID reader comprises a first antenna for receiving the first RFID transponder specific information. The first RFID transponder and the first antenna are fixed relative to the path and on opposite sides of the path. The RFID reader is configured to substantially continuously monitor the first transponder specific information. The presence of the masking component of the guideway-guided vehicle between the first RFID transponder and the first antenna masks the substantially continuous monitoring of the first RFID transponder specific information.

Abstract: A train detection system for detecting a train unit that includes a first transponder interrogator configured to generate one or more request signals for transmission, by a first antenna above a first track location, toward a first fixed transponder at the first track location; a second transponder interrogator configured to generate one or more request signals for transmission, by a second antenna above a second track location, toward a second fixed transponder at the second track location; and a controller communicably connected with the first and second transponder interrogators and configured to verify operation of the train detection system based on receipt of one or more message signals responsive to transmission of the one or more request signals from the first and second transponder interrogators.

Abstract: A locator loop control system includes a guideway configured to define a travel path of a vehicle. The locator loop control system further includes a locator loop located along the guideway, the locator loop configured to exchange information with a vital on-board controller (VOBC) on-board the vehicle. The locator loop control system further includes a first proximity plate located along the guideway, the first proximity plate spaced a first distance along the guideway from the locator loop, and a wayside controller configured to communicate with the locator loop.

Abstract: A control system for a vehicle in a guideway network including a centralized control system configured to generate a first set of instructions. The control system further includes at least one de-centralized control system configured to generate a second set of instructions. The control system further includes an on-board controller configured to receive the first set of instructions and the second set of instructions during a same time period. The on-board controller is configured to receive the first set of instructions using a first communication technique. The on-board controller is configured to receive the second set of instructions via a second communication technique diverse from the first communication technique. If a discrepancy exists, the on-board controller is configured to execute a least restrictive of the first or second set of instructions. The control system is capable of seamlessly transferring control between the two control systems.

Abstract: A system and method provide vital shutdown of a remote slave unit linked by a fiber optic connection to a local, checked redundant master unit with two paired computers. Each computer sends a life signal to an associated local vital supervision card (VSC) and copper to fiber converter (C/F converter) for transmission via fiber to a corresponding fiber to copper converter (F/C converter) on the slave unit, then to a corresponding remote VSC. Each local VSC controls power to a corresponding second local VSC-associated C/F converter, and each remote VSC controls power to a corresponding second remote VSC F/C converter. A VSC detecting an incorrect life signal signature removes power to the corresponding controlled converter and, optionally, to a respective local or remote I/O rack, thereby shutting down the slave unit.

Abstract: Disclosed is a method of controlling a load in a railway signaling system, the method comprising providing a first autonomous controller connectable to the load and a second autonomous controller which is redundant with the first controller such that there is no single point of failure; operating the first and second controllers in one of two modes. There is an on-line mode wherein both controllers provide power to the load to control the load such that current through the load is shared between the first and second controllers. There is an off-line mode wherein a single controller does not provide power to the load and the other controller continues to operate on-line to control the load, whereby control of the load is uninterrupted.

Abstract: A method of determining the position of a vehicle moving along a guideway is disclosed wherein signals from groups of transponders located beside the guideway are detected as the vehicle moves along the guideway to create a footprint in the time domain corresponding to the time the vehicle is in communication with that transponder. The transponders of each group are spaced a known distance apart from each other. An estimate of the position of the moving vehicle is computed by matching the point in the time domain that bears the same geometric relationship to the footprints corresponding to the transponders of the group to a point in the spatial domain that bears a known geometric relationship with the transponders of each group.

Abstract: A system, method, and safety unit provide safety assurance for a multiple redundant system controlling a plant or complex. A unit active line (UAL) status indicates the presence of at least one redundant active unit within the system. A safety verification line (SVL) status verifies the powered down status of all redundant units not active within the system. A safety unit is associated with a vital supervision card (VSC) and vital power bus and the safety unit controls switchable connections from the vital power bus to the UAL and the SVL. Based on verification of UAL and SVL status, system control includes energizing the UAL.

Abstract: An apparatus that determines that a vehicle has moved comprises a shaft member, a pin configured to attach the shaft member to a backing plate via an opening in the shaft member that enables the shaft member to move in a direction along the length of the shaft member, to rotate about the pin, and to contact a surface external to the vehicle when the shaft member is in a first position. The apparatus also comprises a first alignment magnet that attracts the shaft member to the surface external to the vehicle and a first sensor that determines that the shaft member is in the first position. The apparatus further comprises a first holding magnet, a second holding magnet, and at least one sensor that indicates that the shaft member is in contact with the first holding magnet or the second holding magnet, each indicating a direction of movement.