Abstract: A method of controlling braking of a train that includes obtaining in an on-board computer of the train a brake propagation delay time (Td), a brake build-up time (T) and a maximum brake rate (?max) for the train, and controlling braking of the train in the on-board computer by generating one or more braking signals for the train using Td, T and ?max. Also, a methods of determining for a train a profile velocity to a target position of a selected target, selecting a most restrictive target from among a plurality of targets for a train, and determining a plurality of braking parameters for a train having a train consist, wherein the parameters include a brake propagation delay time (Td), a brake build-up time (T) and a maximum brake rate (?max).

Abstract: A method of controlling braking of a train that includes obtaining in an on-board computer of the train a brake propagation delay time (Td), a brake build-up time (T) and a maximum brake rate (?max) for the train, and controlling braking of the train in the on-board computer by generating one or more braking signals for the train using Td, T and ?max. Also, a methods of determining for a train a profile velocity to a target position of a selected target, selecting a most restrictive target from among a plurality of targets for a train, and determining a plurality of braking parameters for a train having a train consist, wherein the parameters include a brake propagation delay time (Td), a brake build-up time (T) and a maximum brake rate (?max).

Abstract: A system includes a global positioning system receiver to determine position of a railroad vehicle, a predetermined track map of possible coordinates of the vehicle, motion sensors providing a positive bias error to determine change in location of the vehicle, an acceleration sensor to determine acceleration of the vehicle, and a processor to vitally determine the location and the location uncertainty of the vehicle on the track map. The processor verifies one motion sensor with another motion sensor, determines a slip or slide condition of the vehicle from one of the motion sensors, determines speed and position of the vehicle from the acceleration sensor during the slip or slide condition, verifies the position of the vehicle from the global positioning system receiver based upon the track map, and corrects the positive bias error of the motion sensors using the position of the vehicle from the global positioning system receiver.

Abstract: A method of controlling braking of a train that includes obtaining in an on-board computer of the train a brake propagation delay time (Td), a brake build-up time (T) and a maximum brake rate (?max) for the train, and controlling braking of the train in the on-board computer by generating one or more braking signals for the train using Td, T and ?max. Also, a methods of determining for a train a profile velocity to a target position of a selected target, selecting a most restrictive target from among a plurality of targets for a train, and determining a plurality of braking parameters for a train having a train consist, wherein the parameters include a brake propagation delay time (Td), a brake build-up time (T) and a maximum brake rate (?max).

Abstract: A system includes a global positioning system receiver to determine position of a railroad vehicle, a predetermined track map of possible coordinates of the vehicle, motion sensors providing a positive bias error to determine change in location of the vehicle, an acceleration sensor to determine acceleration of the vehicle, and a processor to vitally determine the location and the location uncertainty of the vehicle on the track map. The processor verifies one motion sensor with another motion sensor, determines a slip or slide condition of the vehicle from one of the motion sensors, determines speed and position of the vehicle from the acceleration sensor during the slip or slide condition, verifies the position of the vehicle from the global positioning system receiver based upon the track map, and corrects the positive bias error of the motion sensors using the position of the vehicle from the global positioning system receiver.

Abstract: A passive detection system for a levitated vehicle includes track circuits. Each track circuit includes a detection loop having a cable with a first end, a length and a second end. The track circuit also includes a transmitter electrically connected to the first end of the cable and adapted to source a current to the detection loop, and a receiver electrically connected to the second end of the cable and adapted to sense the current from the detection loop. An inductor core includes two openings adapted to receive the length of the cable and two openings adapted to avoid the first and second ends of the cable. The inductor core is adapted to change the sensed current of the receiver, in order to detect a presence of the levitated vehicle at the detection loop. A member is adapted to support the inductor core from the vehicle.

Abstract: A virtual block system is provided in which a section of track is represented by a zone having a plurality of virtual track circuits. Communication between wayside and the vehicle is established within the zone, and may be used to provide the initial position of the vehicle to the carborne equipment. The carborne equipment can then calculate and up-date its position within the zone by using its initial position and sensor information relative to its movement within the zone. The actual position within the zone can be transmitted from the vehicle to the wayside equipment. The wayside equipment converts the actual position within the zone to a virtual track circuit occupancy. The wayside equipment may also use the train length to calculate one or more virtual blocks as being occupied. The wayside unit outputs the occupancy status, occupied or unoccupied, to the wayside interlocking equipment. The wayside equipment generates profile data which can be transmitted to the vehicle.

Abstract: The two inputs of a first flip-flop (FF) are alternately energized over a pair of opposite contacts of a code transmitter. Outputs of a second FF alternately enable a pair of logic gates to pass first or second output pulses of the first FF as clock pulses which drive a counter which produces an output pulse after each preselected count X. Each counter output pulse, equal in length to a half cycle of the code, triggers the second FF to its opposite state. A magnetic stick code repeater relay is driven between its two positions by energy supplied from a normally active driver circuit over another pair of opposite contacts of the code transmitter. The driver circuit is optically coupled to be turned off during each counter output pulse, thus inhibiting repeater relay operation during the corresponding half code cycle. This relay holds in its existing position, blanking a half cycle code period, and then is held by the again active driver circuit during the subsequent half cycle.

Abstract: A pair of transistors, alternately activated by a low frequency generator, alternately connect the positive and negative terminals of the monitored DC source to the common bus of the ground detector apparatus. Each produces a fault current signal flow through any ground fault existing on the other source terminal, with the return circuit including a permanent ground rod, the input of a comparator, and apparatus common. An opposing reference current signal of preselected level is applied to the comparator input, at the same time as each fault signal, from a current pump network driven by the low frequency generator. If each reference current signal is larger than the corresponding fault current signal, the comparator output is a square wave signal of alternate plus and minus pulses which is applied to a negative voltage generator network controlled by contacts of two synchronizing relays alternately driven by the low frequency generator.

Abstract: A tuned transformer element has its primary winding coupled, in series with a fuse of preselected rating, to the rails of the track circuit. A secondary winding supplies input energy to the track circuit receiver unit which detects occupancy conditions of the track section. A third winding is capacitor tuned to resonate with the primary winding at the track circuit frequency. Thus the transformer appears as a parallel resonant load of high impedance in multiple with the track receiver which then operates normally. At propulsion frequency, the impedance of the primary is small while the parallel capacitive reactance is large, so that the parallel network gives the transformer unit a low impedance at this frequency.

Abstract: Insulated joint failure detectors are placed at each controlled signal location in the railroad interlocking to detect the condition of the insulated joints and also the passage of each truck of a train moving in either direction past that signal. Contacts individually responsive to detector operation serially control the lockout of cab signal transmitters to inhibit the transmission of cab signal commands within the interlocking if an insulated joint fails or an unauthorized train overruns a controlled signal. These detector contacts are individually bypassed by parallel circuit paths, controlled either by the corresponding home signal relay or cab signal control relays properly energized along an established route, in order to prevent lockout when the train is authorized to pass that signal location.