A rail-guided permanent way machine is operated by means of a control device in such a way that at least one state variable (Z) of the permanent way machine is determined in dependence on an operating state, and the at least one state variable is compared to at least one pre-defined limit value (G.sub.W, G.sub.S) for monitoring a derailment safety of the permanent way machine. Thus, the derailment safety of the permanent way machine is determined in accordance with the current operating state and monitored. As a result, the permanent way machine has an expanded operating range and increased performance and thus increased efficiency.

A method and a system (30) for inspecting and/or mapping a railway track (18). The method comprises: acquiring geo-referenced rail geometry data associated with geometries of two rails (20) of the track along the section; acquiring geo-referenced 3D point cloud data, which includes point data corresponding to the two rails and surroundings of the track along the section; deriving track profiles of the track from the geo-referenced 3D point cloud data and the geo-referenced rail geometry data; and comparing the track profiles and generating enhanced geo-referenced rail geometry data and/or enhanced geo-referenced 3D point cloud data based on the comparison.

A system and method for inspecting a railway track bed using a plurality of sensors that are synchronized for rapid interrogation of a railway track bed while the sensors are in motion at a high rate of speed.

A positive train control may comprise a plurality of different sensors coupled to a processor that determines whether there is an anomaly of a track way, and if there is, provides an alert and/or a train control action. The plural sensors may include a visual imager, an infrared imager, a radar, a doppler radar, a laser sensor, a laser ranging device, an acoustic sensor, and/or an acoustic ranging device. Data from the plural sensors is geo-tagged and time tagged. Some embodiments of the train control employ track monitors, switch monitors and/or wayside monitors, and some employ locating devices such as GPS and inertial devices.

A method for measuring and displaying the track geometry of a track system uses a track-driveable permanent-way machine, comprising a control measurement system measuring the track position to be corrected before a lifting and lining device, an acceptance measurement system measuring the corrected track position after it, and output units displaying the measured values. The lifting and lining device is controlled depending on the measured values of the control measurement system and the acceptance measurement system to achieve a specified target track geometry. A three-dimensional position image is calculated from the curvature image (k.sub.(s)), longitudinal level image (h.sub.(s)) and superelevation image (u.sub.(s)) of the target track geometry, put into a perspective display, and displayed by the output unit, supplemented by measured error curves for track parameters of track direction, superelevation, twist, and longitudinal level.

In one embodiment, a railroad scout vehicle system includes a scout vehicle and a processing unit. The scout vehicle may include at least two wheels configured to engage a set of railroad tracks, a motor mechanically coupled to at least one of the wheels, a speed controller, an electromagnetic sensor aimed at the set of railroad tracks, a positioning receiver, a local speed sensing device and a transceiver. The speed controller may be coupled to the motor and configured to control the speed of the scout vehicle in order to maintain an appropriate distance between the scout vehicle and a train traveling behind. The processing unit may be configured to transmit the track status information via the transceiver, receive train speed and position signals from the train via the transceiver.

A measuring system comprising a fixed measurement unit (101), a data processing unit (130) and a mobile unit (120). The mobile unit comprises a planar base (111), a reflector (118), an elevation element (119) fixed to the base and the reflector, and attaching the reflector to a fixed position in respect of the base. The mobile unit comprises also mobility means (112) for moving the base along a surface (113) such that the spatial orientation of the base (114) substantially corresponds with the spatial orientation of the currently underlying part of the surface. In addition the mobile unit comprises tilt measuring means (123) for determining a deviation between the spatial orientation of the base and a plane perpendicular to the ambient gravitational force, and tilt elimination means for eliminating the effect of the determined deviation. Measurement results are thus more accurate.

Disclosed is a gradient information acquisition method comprising: a speed measured value acquisition step in which a measured value of the speed of a rail vehicle is acquired; a speed calculation step in which a calculated value of the speed of said vehicle is found using an equation of movement including a parameter indicating the gradient of the path of travel of said rail vehicle; a parameter value acquisition step in which a parameter value is found of a function indicating said gradient, for which parameter the difference of said measured value of the speed and said calculated value of the speed is a minimum; and a gradient information acquisition step of finding the gradient of said path of travel, based on the parameter value of the function indicating said gradient that was acquired in said parameter value acquisition step.

A method validates an obstacle identification system. In order to be able to demonstrate that obstacles are identified by an obstacle identification system at least as reliably as by a driver, it is provided that, in order to form driving scenarios, stochastic combinations of prespecified distributions of submodules are provided. The provided combinations are subjected first, for carrying out a simulation study, to simulation by a simulator and second to automatic processing by an obstacle identification algorithm of the obstacle identification system, and a result of a simulation study, which is carried out by the simulator, and a result of the automatic processing are automatically tested for agreement.

Rail vehicle (1) having rail wheels (3,4) accommodated to guide the rail vehicle along a railway track (2) and said vehicle comprising means for detection of a flaw or flaws in the railway track, wherein the rail vehicle is provided with a noncontact vibrometer (9,10) which is arranged to measure vibrational movement of the railway track surface.