Abstract: Vehicles and related systems and methods are provided for controlling a vehicle in an autonomous operating mode. One method involves identifying a stationary object outside a current lane of travel based at least in part on sensor data captured onboard the vehicle, determining an estimated location for the stationary object based at least in part on the sensor data and a location of the vehicle and providing the estimated location to a remote system. The remote system updates lane preference information corresponding to the estimated location for the stationary object when the stationary object satisfies one or more avoidance criteria. The method continues by determining a trajectory for a vehicle to change lanes based at least in part on the updated lane preference information and autonomously operating one or more actuators onboard the vehicle in accordance with the trajectory.

Abstract: A method of servicing an airfoil for use in a gas turbine engine. The airfoil assembly is defined by a base material and includes an airfoil and a platform from which the airfoil extends. A predetermined amount of the base material is removed from the airfoil assembly proximate to a fillet area of the airfoil assembly via water jet material removal. The fillet area comprises a junction between the airfoil and the platform and is located at an intersection between the airfoil and the platform. A remainder of the base material comprising base material of the airfoil assembly other than proximate to the fillet area is left intact.

Abstract: A battery cell by-pass circuit that has particular application for by-passing cells in a high voltage battery for a vehicle. The battery includes a plurality of battery cells electrically coupled in series. The by-pass circuit includes a first switch electrically coupled in series with one or more of the battery cells, a by-pass line electrically coupled around the one or more battery cells and a second switch electrically coupled in the by-pass line and in parallel with the one or more battery cells. During normal cell operation, the first switch is closed and the second switch is open so that current flows through the one or more battery cells. If the one or more battery cells fail or are failing, the first switch is opened and the second switch is closed so that current by-passes the one or more cells and they are removed from the battery circuit.

Abstract: A by-pass circuit for a battery system that disconnects parallel connected cells or modules from a battery circuit or controls the current through the parallel connected cells or modules. If a cell has failed or is potentially failing in the system, then the by-pass circuit can disconnect the cell or module from other cells or modules electrically coupled in parallel. If a cell or module has a lower capability than another cell or module, then the by-pass circuit can control the current to the cell or module to maximize the performance of the system and prevent the system from creating a walk-home condition.

Abstract: A by-pass circuit for a battery system that disconnects parallel connected cells or modules from a battery circuit or controls the current through the parallel connected cells or modules. If a cell has failed or is potentially failing in the system, then the by-pass circuit can disconnect the cell or module from other cells or modules electrically coupled in parallel. If a cell or module has a lower capability than another cell or module, then the by-pass circuit can control the current to the cell or module to maximize the performance of the system and prevent the system from creating a walk-home condition.

Abstract: A battery cell by-pass circuit that has particular application for by-passing cells in a high voltage battery for a vehicle. The battery includes a plurality of battery cells electrically coupled in series. The by-pass circuit includes a first switch electrically coupled in series with one or more of the battery cells, a by-pass line electrically coupled around the one or more battery cells and a second switch electrically coupled in the by-pass line and in parallel with the one or more battery cells. During normal cell operation, the first switch is closed and the second switch is open so that current flows through the one or more battery cells. If the one or more battery cells fail or are failing, the first switch is opened and the second switch is closed so that current by-passes the one or more cells and they are removed from the battery circuit.

Abstract: A method of servicing an airfoil for use in a gas turbine engine. The airfoil assembly is defined by a base material and includes an airfoil and a platform from which the airfoil extends. A predetermined amount of the base material is removed from the airfoil assembly proximate to a fillet area of the airfoil assembly via water jet material removal. The fillet area comprises a junction between the airfoil and the platform and is located at an intersection between the airfoil and the platform. A remainder of the base material comprising base material of the airfoil assembly other than proximate to the fillet area is left intact.

Abstract: A multiple piece turbine airfoil having an outer shell with an airfoil tip that is attached to a root with an internal structural spar is disclosed. The root may be formed from first and second sections that include an internal cavity configured to receive and secure the one or more components forming the generally elongated airfoil. The internal structural spar may be attached to an airfoil tip and place the generally elongated airfoil in compression. The configuration enables each component to be formed from different materials to reduce the cost of the materials and to optimize the choice of material for each component.

Abstract: A pattern of depressions (36) in a sealing surface (34) on a CMC wall (32) of gas turbine ring segment (30) allows minimum clearance against turbine blades tips, and thus maximizes working gas sealing. An array of depressions (36) on the surface (34) increases abradability of the surface (34) by blade tip contact during zero clearance conditions and reduces blade tip damage. The depressions (36) are unconnected, preventing bypass of the working gas around the blade tips. A desired abradable surface geometry may be formed in a stacked laminate wall construction (40-43, 52) by staggered laminate edge profiles (50, 52) or by machining of depressions (36, 54) after construction.

Abstract: A ceramic ring segment for a turbine engine that may be used as a replacement for one or more metal components. The ceramic ring segment may be formed from a plurality of ceramic plates, such as ceramic matrix composite plates, that are joined together using a strengthening mechanism to reinforce the ceramic plates while permitting the resulting ceramic article to be used as a replacement for components for turbine systems that are typically metal, thereby taking advantage of the properties provided by ceramic materials. The strengthening mechanism may include a bolt or a plurality of bolts designed to prevent delamination of the ceramic plates when in use by keeping the ceramic plates in compression.

Abstract: A ceramic ring segment for a turbine engine that may be used as a replacement for one or more metal components. The ceramic ring segment may be formed from a plurality of ceramic plates, such as ceramic matrix composite plates, that are joined together using a strengthening mechanism to reinforce the ceramic plates while permitting the resulting ceramic article to be used as a replacement for components for turbine systems that are typically metal, thereby taking advantage of the properties provided by ceramic materials. The strengthening mechanism may include a bolt or a plurality of bolts designed to prevent delamination of the ceramic plates when in use by keeping the ceramic plates in compression.

Abstract: Aspects of the invention relate to a ring seal for a turbine engine. The ring seal can be made up of a plurality of circumferentially abutted ring seal segments. Each ring seal segment can comprise a plurality of individual channels. The channels can be generally U-shaped in cross-section with a forward span, and aft span and an extension connecting therebetween. The channels can be positioned such that the aft span of one channel can substantially abut the forward span of another channel. The plurality of separate channels can be detachably coupled to each other by, for example, a plurality of pins. The ring seal segment according to aspects of the invention can facilitate numerous advantageous characteristics including greater material selection, selective cooling, improved serviceability, and reduced blade tip leakage. Moreover, the configuration is well suited to handle the operational loads of the turbine.

Abstract: Aspects of the invention relate to a ring seal for a turbine engine. The ring seal can be made up of a plurality of circumferentially abutted ring seal segments. Each ring seal segment can comprise a plurality of individual channels. The channels can be generally U-shaped in cross-section with a forward span, and aft span and an extension connecting therebetween. The channels can be positioned such that the aft span of one channel can substantially abut the forward span of another channel. The plurality of separate channels can be detachably coupled to each other by, for example, a plurality of pins. The ring seal segment according to aspects of the invention can facilitate numerous advantageous characteristics including greater material selection, selective cooling, improved serviceability, and reduced blade tip leakage. Moreover, the configuration is well suited to handle the operational loads of the turbine.

Abstract: A multiple piece turbine airfoil having an outer shell with an airfoil tip that is attached to a root with an internal structural spar is disclosed. The root may be formed from first and second sections that include an internal cavity configured to receive and secure the one or more components forming the generally elongated airfoil. The internal structural spar may be attached to an airfoil tip and place the generally elongated airfoil in compression. The configuration enables each component to be formed from different materials to reduce the cost of the materials and to optimize the choice of material for each component.

Abstract: A CMC airfoil (20) formed with CMC stitches (37) interconnected between opposed walls (26, 28) of the airfoil to restrain outward flexing of the walls resulting from pressurized cooling air within the airfoil. The airfoil may be formed of a ceramic fabric infused with a ceramic matrix and dried, and may be partially to fully cured. Then holes (32, 34) are formed in the opposed walls of the airfoil, and a ceramic stitching element such as ceramic fibers (36) or a ceramic tube (44) is threaded through the holes. The stitching element is infused with a wet ceramic matrix before or after threading, and is flared (38) or otherwise anchored to the walls (26, 28) to form a stitch (37) there between. The airfoil and stitch are then cured. If the airfoil is cured before stitching, a pre-tension is formed in the stitch due to relative curing shrinkage.

Abstract: Aspects of the invention relate to a modular turbine vane assembly. The vane assembly includes an airfoil portion, an outer shroud and an inner shroud. The airfoil portion can be made of at least two segments. Preferably, the components are connected together so as to permit assembly and disassembly of the vane. Thus, in the event of damage to the vane, repair involves the replacement of only the damaged subcomponents as opposed to the entire vane. The modular design facilitates the use of various materials in the vane, including materials that are dissimilar. Thus, suitable materials can be selected to optimize component life, cooling air usage, aerodynamic performance, and cost. Because the vane is an assemblage of smaller sub-components as opposed to one unitary structure, the individual components of the vane can be more easily manufactured and more intricate features can be included.

Abstract: A pattern of depressions (36) in a sealing surface (34) on a CMC wall (32) of gas turbine ring segment (30) allows minimum clearance against turbine blades tips, and thus maximizes working gas sealing. An array of depressions (36) on the surface (34) increases abradability of the surface (34) by blade tip contact during zero clearance conditions and reduces blade tip damage. The depressions (36) are unconnected, preventing bypass of the working gas around the blade tips. A desired abradable surface geometry may be formed in a stacked laminate wall construction (40-43, 52) by staggered laminate edge profiles (50, 52) or by machining of depressions (36, 54) after construction.

Abstract: A ceramic matrix composite with an enhanced abradability has a patterned surface with an array of solid composite material and voids where the voids extend into but not through the composite. The flow of gas through the voids as the surface is traversed by an impinging component, such as a turbine blade tip, is inhibited by the shape and size of the voids which can be sealed by the passing blade tip. Separately or additionally the inhibition of gas flow can result from the filling of the voids with a ceramic material of higher abradability than the ceramic matrix composite.

Abstract: Aspects of the invention are directed to a ceramic matrix composite ring seal segment. The ring seal segment according to aspects of the invention includes a relatively simple body that is circumferentially curved. At least a portion of the hot gas path surface of the ring seal segment can be coated with a thermal insulating. material. In one embodiment, each ring seal segment can be operatively connected to a stationary support structure, such as by way of isolation rings. The ring seal segments and/or the isolation rings can be configured so as to restrain the ring seal segments in the axial, radial and/or circumferential directions. The ring seal segments can be attached to the isolation rings so that the support points act opposite the operating pressure loads. Thus, the ring seal segments carry these loads in compression, a strong direction of the CMC fibers.

Abstract: A CMC airfoil (20) formed with CMC stitches (37) interconnected between opposed walls (26, 28) of the airfoil to restrain outward flexing of the walls resulting from pressurized cooling air within the airfoil. The airfoil may be formed of a ceramic fabric infused with a ceramic matrix and dried, and may be partially to fully cured. Then holes (32, 34) are formed in the opposed walls of the airfoil, and a ceramic stitching element such as ceramic fibers (36) or a ceramic tube (44) is threaded through the holes. The stitching element is infused with a wet ceramic matrix before or after threading, and is flared (38) or otherwise anchored to the walls (26, 28) to form a stitch (37) there between. The airfoil and stitch are then cured. If the airfoil is cured before stitching, a pre-tension is formed in the stitch due to relative curing shrinkage.