Abstract: A system may include a vehicle system including at least one vehicle, wherein the at least one vehicle includes at least one handbrake. The system may also include a handbrake setting determination unit configured to determine a handbrake setting control input indicating whether the at least one handbrake is to be set in order to park the vehicle system at a particular location without moving. A handbrake setting suggestion may be based on the handbrake setting control input.

Abstract: A control system for a fuel tender of a locomotive includes an input module, a sensor module, a processor unit, and at least one actuator. The input module is configured to generate a first signal based on one or more inputs received from an operator of the locomotive. The sensor module is configured to generate a second signal based on one or more operating parameters of at least one of the locomotive and the fuel tender. The processor unit is configured to generate a first actuation signal based on at least one of the first signal and the second signal. The actuator is disposed in electrical communication with the processor unit and the fuel tender. The actuator is configured to selectively perform at least one of enabling or disabling fuel flow from the fuel tender to the locomotive based on the first actuation signal.

Abstract: A method for controlling vehicle progression along a ride path of an amusement park ride. The method includes receiving inputs from a passenger of a vehicle on the ride path and processing the received inputs to determine a vehicle state change. The method includes determining a present or predicted vehicle state and comparing the present or predicted vehicle state with constraints defined by a dynamic boundary associated with the vehicle. The method includes issuing vehicle control commands to a drive assembly to implement the vehicle state change if it complies with the constraints. The dynamic boundary is moved logically along the ride path at a nominal speed to define a set of boundaries for movement of the vehicle along the ride path. The vehicle state change may be a change that causes the vehicle to travel at a speed differing from the dynamic boundary while remaining within the dynamic boundary.

Abstract: A system for communicating a dataset may include at least a first and a second communication line. The system may also include a first transceiver configured to communicate a first data signal indicative of the dataset over the first communication line and a second transceiver configured to communicate a second data signal indicative of the dataset over the second communication line. The system may also include a processor. The processor may be configured to receive the first data signal and the second data signal and compare the first data signal and the second data signal to determine whether the first data signal or the second data signal comprises a more accurate signal. The processor may also be configured to determine the dataset based upon the more accurate signal.

Abstract: A collision avoidance system (CAS) is described that includes one or more sensor technologies, including, for example, an Ultra Wideband (UWB) sensing technology. The collision avoidance system is designed to reliably track the location and speed of vehicles and the distance between vehicles over a wide variety of track and terrain. The collision avoidance system may utilize information from a variety of sensor technologies to determine whether one or more vehicles violate speed and/or separation criteria, and may generate a warning.

Abstract: A system includes a transceiver for receiving one or more communications from a communication device in a railway vehicle; a microcontroller that is configured for communication with the transceiver and that is configured to control a position of a switch in the railway; and an electronic subsystem for interfacing with the microcontroller and with the switch; wherein the trans transceiver is configured to transmit to the microcontroller at least one of the one or more communications received from the railway vehicle; wherein the microcontroller is further configured to extract a command from the parsed contents; wherein the microcontroller is further configured to transmit the command to the electronic subsystem to cause the electronic subsystem to transition the switch to a position specified by the command; and wherein transitioning of the switch to the specified position enables the railway vehicle to cross the switch.

Abstract: An apparatus for operating a railway system, the railway system comprising a lead vehicle consist, a non-lead vehicle consist and railcars, the apparatus including a first element for determining a slack condition of railway system segments, wherein the segments are delineated by nodes, and a control element configured to control an application of tractive effort or braking effort of the lead vehicle consist or the non-lead vehicle consist.

Abstract: In a catenary-based transportation system which is provided with integrated power supply equipment having an electricity storage unit which stores electricity regenerated by vehicles traveling by electricity received from a catenary and supplies electricity to the catenary and the other power supply system which is a power supply system different from the electricity storage unit concerned, the performance of a rectifier of the other power supply system is determined based on a power-supplying contribution ratio ? of the other power supply system so that the cost value of the integrated power supply equipment becomes lower than a target cost value.

Abstract: A distributed power (DP) control system is contained within a non-freight carrying intermodal container for communicating with and receive instructions and/or commands from a command system of a lead distributed power locomotive within a train. The container is configured to be provided on a car adjacent to a remote non-distributed powered (non-DP) locomotive provided within a length of the train. One or more connection hoses connect the distributed power control system within the container to the non-DP locomotive to control application of at least its brake system.

Abstract: A steering system, method, and computer-readable medium for controlling a steerable, self-propelled vehicle for travelling in an end-to-end series of steerable, self-propelled vehicles, the vehicle including a plurality of individually controllable propelling devices connected at a generally vertical pivot to an axle of the vehicle. The steering system includes: an angle sensor for detecting an inter-vehicle angular position between two of the vehicles and providing a corresponding signal indicative thereof; a distance sensor for detecting an inter-vehicle distance between two of the vehicles and providing a corresponding signal indicative thereof; and a controller system. The controller system is configured to: receive the signals from the angle sensor and the distance sensor, control a speed of each propelling device based on the inter-vehicle distance, and control an angle of each propelling device based on the inter-vehicle angular position.

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: Various embodiments of methods and systems are provided for enhancing engine operation through data-sharing among vehicles. In one embodiment, a method includes determining whether a first value of a first operating parameter produced by a first vehicle is corrupted or unavailable; receiving a second value of the first operating parameter produced by a second vehicle that is proximate to the first vehicle; adjusting the second value by a first adjustment factor, the first adjustment factor based on a first value of a global positioning system (GPS) position of the first vehicle produced by the first vehicle and a second value of a GPS position of the second vehicle produced by the second vehicle; and in response to determining that the first value is corrupted or unavailable, controlling operation of an engine of the first vehicle based on the adjusted second value of the first operating parameter.

Abstract: Occupancy of a railroad track detection zone by one or more trains is determined using sensor devices located at gateways into and out of the track detection zone. Each sensor device has a sensing range that includes a portion of the railroad track in the detection zone and the sensor device generates data used to uniquely identify each train passing through a gateway and thus the sensing range of one or more sensor devices. Data from the detection zone's sensor device array is collected and evaluated to monitor or track the status of any detected trains and the occupancy of the zone. In some embodiments, the sensor devices utilize anisotropic magnetoresistive sensor elements whose analog waveform data is the basis of magnetic flux peak detection and mapping to generate unique train identification signature data that is transmitted to and evaluated by a detection zone processor, which in some cases can control crossing signals and/or other control apparatus related to the railroad track detection zone.

Abstract: A multi-mode control system for a locomotive includes a throttle control device having notch settings corresponding to, for a first, long haul mode, control signals for providing respective tractive effort or power from the locomotive, a master controller in communication with the throttle control device and adapted to receive said control signals from the throttle control device and to transmit respective command signals to power-train components of the locomotive to achieve the respective tractive effort or power, the master controller also adapted for sending alternative command signals when a user-operable mode selector is set to one of one or more alternative modes. The user-operable mode selector includes one or more user interface devices in communication with the master controller for selecting one alternative mode of the one or more alternative modes.

Abstract: The present disclosure is directed to a distributed control system for a locomotive. The distributed system may include a network and a plurality of electronic modules spatially distributed within the locomotive and communicatively coupled to the network in a standardized scalable architecture. A first electronic module of the plurality of electronic modules includes a first configurable controller and a programmable controller, and a second electronic module of the plurality of electronic modules includes a second configurable controller and does not include a programmable controller.

Abstract: A system to optimize performance of a powered system, the system including a data device configured to provide current information about current operating conditions of the powered system and/or prior information about the powered system, a controller configured to control operation of the powered system, and a processor configured to provide at least one control command to the controller for use in operating the powered system and/or user information with at least one recommended command to a user to control the powered system, wherein the at least one control command and/or user information are based at least in part on the current information and/or the prior information. A system and computer software code, stored on a computer readable media and executable with a processor, are also disclosed.

Abstract: A train control system includes: an on-board device 3 mounted on each of trains 2; a vehicle radio set 4; wayside radio sets 5 disposed on a ground; and a ground device 6 connected to the wayside radio sets 5. The ground device 6 obtains a location information of a train 2 and a location information of a following train 2 based on results of distance measurement based on communication between the wayside radio sets 5 and the vehicle radio sets 4, and the ground device 6 transmits them to an on-board device 3 of the train 2. The on-board device 3 calculates a stop limit position of the following train 2 based on the location information of the train 2 and the location information of the following train 2, and the on-board device 3 transmits the calculated stop limit position to the following train 2.

Abstract: A system is provided that includes a remote communication module, a control module, and a determination module. The remote communication module is configured to be disposed onboard a remote consist of a vehicle system, and is communicatively connected to at least one additional consist of the vehicle system. The control module is configured to be disposed onboard the remote consist and to provide control commands to at least one powered unit of the remote consist. The determination module is configured to be disposed onboard the remote consist and to determine capability information corresponding to the ability of the at least one powered unit of the remote consist to perform a first command received from one of the at least one additional consist. The determination module is also configured to determine a second command provided to the control module using the first command and the capability information.

Abstract: A device for monitoring the status of a railcar handbrake having a hand operated handle, which device has a load bearing member configured to be inserted in the linkage of a railcar handbrake system so that the force applied to the brake system passes through the load bearing member. A strain gauge mounted on the load bearing member measures the strain. The information from the strain gauge is indicative of the force applied by the handbrake to the brake and is used to determine the status of the handbrake. Means for determining motion of the railcar is also provided. In one form, if it is determined that the brake is on and the railcar is in motion, information, such as an alarm, is transmitted. A system and method of monitoring a railcar handbrake are also provided.

Abstract: An empty-load device feedback arrangement for a train with the railcar having an air brake arrangement with an one air-operable braking assembly, the arrangement including: an empty-load device having: at least one sensor arrangement to sense a load associated with the railcar; a braking assembly input exhibiting a delivered air pressure; a regulation arrangement to regulate air pressure; and a braking assembly output exhibiting a regulated air pressure; and a pressure sensor to: sense the regulated air pressure of the air being delivered to the air-operable braking assembly; and generate a regulated air pressure signal. An air brake arrangement is also disclosed.

Abstract: The present invention provides an in-vehicle congestion-status display system that notifies railway users of a congestion status of each vehicle of a train. The in-vehicle congestion-status display system includes a main server that calculates a congestion rate immediately before boarding, which is a predicted value of a congestion rate when alighting of users is complete, of each vehicle of a train, based on a congestion rate during travel and an alighting rate acquired in a past and held as information indicating a difference between a congestion rate during travel immediately before arriving at the station and a congestion rate when alighting of users is complete after arriving at a next stop of the train, and a display device that notifies users of the congestion rate immediately before boarding calculated for each vehicle of the train.

Abstract: The present invention provides a passenger guidance display system comprising a service managing apparatus configured to manage on-rail information and a service schedule of a train and a passenger guidance display apparatus provided in a station premise and configured to perform display of passenger guidance using service information of a train scheduled to arrive next transmitted from the service managing apparatus.

Abstract: A locomotive assembly including a legacy locomotive controller and an intercept locomotive controller and a method of controlling a locomotive are disclosed. The locomotive assembly includes a power bus, a locomotive, and an intercept locomotive controller. The locomotive includes a primary power unit coupled to the power bus and a legacy locomotive controller programmed to transmit a control command to the primary power unit. The intercept locomotive controller is electrically coupled between the locomotive controller and the primary power unit and is programmed to intercept an initial locomotive control signal transmitted from the legacy locomotive controller to the primary power unit indicating an amount of locomotive power, modify the initial locomotive control signal, and transmit the modified control signal to the primary power unit.

Abstract: A detection system may include a transmitter associated with a first train configured to emit an end-of-train signal. The detection system may include a receiver associated with the transmitter and configured to receive the end-of-train signal from the transmitter. The receiver may also be configured to receive at least one remote signal from a second train and determine whether the second train is a collision threat based on the remote signal from the second train.

Abstract: With respect to each of trains, a ground device 6 detects a train location in the control section on the basis of a propagation time of a radio wave between a vehicle radio set 4 and a wayside radio set 5, in the case in which the ground device 6 determines that the number of trains has reached the controllable number of trains or there is the possibility that the number of trains reaches the controllable number of trains in its own control section, a ground device 6 disposed in an adjacent control section to the control section in which the number of trains is reaching the controllable number of trains, when a train 2 scheduled to travel toward the control section stops in a station 8, prevents departure of the train 2 scheduled to pass through the border of the control section by making the train 2 wait at the station 8.

Abstract: A method for routing data between access points in a locomotive consist including at least three locomotives is disclosed. The method may include monitoring at least one characteristic of a first data transmission between a first access point in a first locomotive and a third access point in a third locomotive. The method may also include determining, based on the monitored characteristic, whether to route a second data transmission from the first access point to the third access point through a second access point in a second locomotive that is physically disposed between the first locomotive and the third locomotive.

Abstract: A ground device 1 transmits train control information to an on-board device mounted on a train. The ground device 1 receives a train detection signal (TD signal) from a train with an ATC/TD on-board device mounted thereon through loop coils 21 to 2m, and receives a train position signal from a train with a CBTC on-board device mounted thereon through wayside radio sets 61 to 6n. Based on the input train detection signal and train position signal, the ground device 1 detects the position of each train traveling on a route R, generates control information on each train based on the detected position of each train, and converts the control information to an ATC signal and a CBTC signal. The ATC signal is transmitted to the loop coils 21 to 2m through information transmission units 4, and the CBTC signal is transmitted through the wayside radio sets 61 to 6n.

Abstract: A vehicle management system for automatic vehicles running on a guideway independent of wayside signals or interlocking devices includes intelligent on-board controllers on each vehicle for controlling operation of the vehicle. The on-board controllers communicate with each other as well as individual wayside devices and a data storage system to identify available assets needed to move along the guideway and to reserve these assets for their associated vehicle.

Abstract: A system and method for determining dynamically changing distributions of vehicles in a vehicle system are disclosed. The system and method determine handling parameters of the vehicle system. The handling parameters are determined for different distributions of the vehicles among different groups at different potential change points along a route. The system and method also determine whether to change the distributions at potential change points based on the handling parameters. Based on determining that the distributions are to change, a selected sequence of changes to the distributions is determined at one or more of the potential change points along the route. Change indices are generated based on the selected sequence. The change indices designate times and/or the one or more potential change points at which the distributions changes. The vehicles included in a common group have common designated operational settings while the vehicles are in the common group.

Abstract: A data improvement system, including an initial database, a verification database, and a processing device in communication with the initial database and the verification database. The processing device receives data from the initial database and the verification database, and determines verification data based thereon. A track data improvement system and a track database improvement system are also disclosed.

Abstract: A track-data verification vehicle and method for verifying positive train control (PTC) track data. The vehicle includes a 360° camera and a precision positioning system co-located on a vertical axis on the vehicle. The 360° camera provides a video image with indicators that are useable to align an asset with the positioning system. A second video camera is positioned interior to the vehicle to capture an image of a monitor associated with a train management control (TMC) unit and of operator inputs to the TMC unit; the TMC unit executes a PTC track-data verification application. The process of verifying asset locations is thus recorded and can be reviewed and approved by a Federal Railroad Administration representative without requiring the representative to be physically present within the vehicle during track-data verification.

Abstract: In a regenerative braking emergency stop system, a substation includes: a rectifier transformer configured to transform AC power received from outside; a rectifier configured to convert the transformed AC power into DC power; and a switch disposed on an electrical path between the rectifier and a power-feed rail and configured to be in a closed state or an opened state; a simulated ripple transmitter configured to transmit a simulated ripple, the simulated ripple being an AC signal having a predetermined frequency; a superimposing circuit connected to the power-feed rail in parallel with the rectifier and configured to superimpose the simulated ripple transmitted from the simulated ripple transmitter on DC power outputted from the rectifier; and a relay device configured to allow the simulated ripple transmitter to transmit the simulated ripple when the rectifier is receiving power from outside and the switch is in a closed state.

Abstract: A track brake includes at least one vertically movable, more particularly lowerable, braking element and an inclination sensor disposed in such a manner that a respective position of the at least one vertically movable braking element can be determined on the basis of at least one measurement value of the inclination sensor. A method for determining the position of at least one vertically movable, more particularly lowerable, braking element of a track brake is also provided.

Abstract: A method, system, and computer readable medium may be provided for train monitoring. Track circuit data may be received including an indication of a shunted track circuit on a train track. The received track circuit data and shunted track circuit may be analyzed. A train may be tracked on the train track based on the received track circuit data. A loss in physically expected track circuit occupancy in a path of the train may be detected. A graph may be generated showing the at least one shunted track circuit over time. The graph may indicate losses or abnormalities in physically expected track circuit occupancy in the path of the train, velocity of the train, acceleration of the train, and/or a size of the train. An alert with the severity and track circuit identifier may be generated and transmitted.

Abstract: A method for operating a railway section that includes section elements, which are each actuated by a processor that is reliable in terms of signaling and cyclically carries out a test routine. A railway section is configured for carrying out the method. In order to save energy and cost, the processor is operated selectively in active mode or sleep mode. From the sleep mode the processor is switched to the active mode for the duration of the test routine by way of a timer logic element that is reliable in terms of signaling.

Abstract: With first and second wagons (1, 3), including an emitter similar to the one of an access point and a receiving wagon (2), including a receiver similar to the one of a device onboard a train and measuring a quantity relating to a received signal, this method consists of: placing the first wagon at a previous implantation point while the emitter of the first wagon emits a first signal, moving the receiving wagon away from the first wagon; when the quantity relating to the first signal is under a threshold, immobilizing the receiving wagon;—while the emitter of the second wagon emits a second signal, moving the second wagon away from the receiving wagon; when the quantity relating to the second signal is under the threshold, immobilizing the second wagon; and storing its position as the implantation point of an access point.

Abstract: The invention relates to an apparatus and method which allows information representing a state or condition or an action to be performed as part of a control system to be present to one or more users. The information is selected and generated in a manner which removes or at least reduces the risk of potentially catastrophic error occurring which would be possible if, for example, the information is corrupt or lost during subsequent transmission, remote processing and/or displaying. One such use of the apparatus and method of the invention is in relation to transport vehicles and the control of the movement of said vehicles along predefined geographical paths.

Abstract: An on-board device capable of receiving train control signals from ground-side equipment of train control systems of different types or the like to control the speed of a train and the like appropriately, is provided. An on-board device 10 mounted on a train 1 includes ATC/TD antennas 11a, 11b that receive an ATC signal including train control information from loop coils installed along a route of the train 1, a vehicle radio set 12 that receives a CBTC signal including train control information from wayside radio sets installed along the route, an ATC control unit 141 that controls the train 1 based on the train control information in the ATC signal, a CBTC control unit 142 that controls the train 1 based on the train control information in the CBTC signal, and a selection unit 143 that selects the ATC control unit 141 or the CBTC control unit 142.

Abstract: The present invention provides a method for improving operation density of rail vehicles and for preventing head-on collision and rear-ending collision. Said method divides a rail line into equidistant electronic zones, the length of a zone being greater than the shortest safe distance between two running vehicles. Said method installs a locomotive passing detection alarm device in each zone, when a locomotive travels at high speed on the rail, the locomotive passing detection alarm device corresponding to the zone occupied by the locomotive itself will simultaneously access adjacent front and back zones, and determine whether the two adjacent zones are simultaneously occupied by locomotives. If the two adjacent. zones are simultaneously occupied by locomotives, the locomotive passing alarm device will send an alarm signal to the locomotives to warn or otherwise take measures.

Abstract: A system for operating a remotely controlled powered system, the system including a feedforward element configured to provide information to the remotely controlled powered system to establish a velocity, and a feedback element configured to provide information from the remotely controlled powered system to the feedforward element. A method and a computer software code are further disclosed for operating the remotely controlled powered system.

Abstract: A method and system for verifying trackside conditions in safety critical railroad applications by reporting the status of trackside signals and switches to a remote train control system. The system comprises at least one sensor for providing trackside conditions electrically connected to a circuit for providing trackside conditions to a railroad, said sensor being powered by voltage applied to the circuit such that the sensor is energized only when said electrical component is engaged. The system and method further comprises a method and system which is failsafe and which enables the control system to independently verify signals from each sensor.

Abstract: A rail vehicle braking device has at least one first electrodynamic brake with a drive unit that includes at least one drive motor and a power supply unit for supplying the drive motor in a traction mode of the drive unit. A brake control unit controls, in a first brake mode, the respective power supply unit for providing a braking effect. In order to optimize the system with a fall-back measure in case of a braking effect loss in respect of the cause thereof, there is provided at least one sensor unit, which detects a braking effect parameter for the first braking mode of the brake. A monitoring device is assigned to the first brake. It is independent of the brake control unit and considers, in a first monitoring mode, the braking effect parameter for the introduction of a fall-back measure concerning the brake.

Abstract: A system and method optimizes energy consumption in a railway system including a set of trains, a set of energy storage devices, and a set of substations connected to a grid by first optimizing control parameters controlling at least part of the energy consumption of the railway system to produce optimized control parameters. The optimized control parameters minimize, over multiple time steps, a combination of total power provided by the grid to satisfy a power demand of the railway system, a state-of-charge of each energy storage device, power supplied to charge the energy storage device and power supplied by the energy storage device. The optimizing is subject to constraints on operations of the railway system over multiple time steps. The constraints include a complementarity constraint. A command is generated to control the energy consumption of the railway system based on the optimized control parameters.

Abstract: Embodiments of an integrated rail efficiency and safety support system and method are shown comprising a server operable to receive a plurality of sets of collected information, each of the sets of collected information comprising a consist physical location and weather conditions and rail temperatures in an area of the respective consist and to process a predictive rail temperature algorithm for predicting a rail temperature and/or a trend in rail temperature for a selected section of track; and wherein the predictive rail temperature algorithm factors the information provided to it and provides a predicted rail temperature and/or trend in rail temperature for the selected section of track.

Abstract: A system, in a vehicle consist including at least a fuel car operably connectable to a powered vehicle via a fuel distribution path, includes a communication module and a determination module. The communication module is configured to communicate via a first channel and a second channel. The second channel is associated with the fuel distribution path and is configured to communicate a status signal. The determination module is configured to associate the fuel distribution path with the powered vehicle based at least in part on at least one of the status signal or an acknowledgment message indicating receipt of the status signal.

Abstract: A blocked rail crossing detection and notification system is described. The system includes a processing device, a communications interface communicatively coupled to the processing device and operable for facilitating communications between the processing device and at least one external device, and at least one vehicle detection mechanism placed proximate to a rail grade crossing. The at least one vehicle detection mechanism is communicatively coupled to the processing device and operable to provide signals to the processing device indicative of the presence or non-presence of a vehicle within a defined area surrounding an intersection of a roadway and one or more railroad tracks. The processing device is further programmed to communicate the presence or non-presence of a vehicle along with supporting correlative visual data within the defined area to the at least one external device via the communications interface.

Abstract: A communication system includes a data manager unit, a private interface, and an open interface. The data manager unit is configured to be disposed onboard a vehicle and to manage a transmission of data from a control system of the vehicle to a plurality of applications. The private interface is configured to communicably couple the data manager unit to the control system of the vehicle, and to limit communication with the control system via a connection protocol, wherein the connection protocol is configured to prevent direct communication between the data manager unit and an application that does not use the connection protocol. The open interface is configured to communicably couple the data manager unit and the plurality of applications.

Abstract: A method, performed by a computer having a processor and system memory, for calibrating a tie height of a ballast profiling rail vehicle having a remote sensing system, includes traversing the rail vehicle along a first calibration section of railroad track at a calibration speed, detecting, using the remote sensing system, a plurality of height to tie measurements in the first calibration section, establishing a rolling median average of the height to tie measurements, and determining a calibration tie height relative to the rail vehicle based upon the rolling median average.

Abstract: A trainline network access point connected to an intra-consist electrical cable of a consist has a network data signal path, a first communication module, a second communication module, and a network switch. The network switch is connected to the first communication module and the second communication module and configured to selectively connect the network data signal path to the first communication module and the second communication module. The first communication module has a first processor configured to receive first network data via the network data signal path, modulate the first network data for transmission over the intra-consist electrical cable, and transmit the first modulated network data over the intra-consist electrical cable.

Abstract: Various methods and systems are provided for initiating and executing a fuel routine for a vehicle. In one embodiment, a method comprises sending from a controller of a vehicle a fuel request to a fuel tender to reduce a pressure of gaseous fuel on the fuel tender and adjusting one or more vehicle operating parameters to allow consumption of the gaseous fuel at an engine of the vehicle when the pressure of the gaseous fuel is below a threshold supply pressure.