Abstract: An aircraft is provided and includes a rotor, which is rotatable relative to an airframe, a rotor, which is rotatable relative to the airframe and which generates a rotor induced vibration, an engine to generate rotational energy, a drive portion to transfer the rotational energy from the engine, a gearbox disposed to transmit the rotational energy from the drive portion to the rotor to drive rotor rotation, support members connecting the gearbox to the airframe and an actuation system configured to generate an anti-vibration load applicable to the gearbox via an actuator comprising an actuator element disposed along one of the support members and a stinger element extending from the actuator element to a connection point of the support member and the gearbox to transmit a portion of the anti-vibration load from the actuator element to the connection point to counter the rotor induced vibration at the gearbox.

Abstract: Various systems and methods are described for controlling spark plug fouling and pre-ignition in a newly manufactured vehicle. One method comprises, during a pre-delivery phase of the newly manufactured vehicle including an engine, operating the engine with a first setting for air/fuel ratio to reduce spark plug fouling, and adjusting the first setting of the air/fuel ratio responsive to pre-ignition.

Abstract: Methods and systems are provided for leveraging engine skip-fire operation during an engine cold-start to expedite catalyst heating. Based on the heat flux required, the engine may be operated with a group of cylinders selectively deactivated, with spark retard on remaining active cylinders increased, and with engine speed increased to reduce NVH issues during the skip-fire operation. The combination of parameters may be adjusted based on changes in exhaust temperature and NVH limits of the engine.

Abstract: Methods and systems are provided for adjusting a phase of gaseous fuel delivered to fuel injectors of a fuel delivery system. In one example, a method may include adjusting a fuel pressure in a fuel delivery system to deliver fuel in each of a liquid and a gaseous phase during different engine operating conditions. The fuel pressure may be based on a temperature, composition, and desired phase of the fuel.

Abstract: Methods and systems are provided for addressing pre-ignition occurring while operating with blow-though air delivery. A variable cam timing device used to provide positive intake to exhaust valve overlap is adjusted in response to an indication of pre-ignition to transiently reduce valve overlap. Pre-ignition mitigating load limiting and enrichment applied during a blow-through mode is adjusted differently from those applied when blow-through air is not being delivered.

Abstract: Methods and systems are provided for inferring spark plug fouling due to accumulation of fuel additives thereon. In one example, an engine controller may infer spark plug hot fouling based on higher than expected exhaust temperatures by correlating the elevated exhaust temperature with late combustion phasing due to additive accumulation. A confidence factor of the spark plug hot fouling detection may be enhanced based on data regarding concurrent misfire and/or pre-ignition events.

Abstract: Methods and systems are provided for adjusting spark and/or fuel injection to a cylinder based on late combustion, partial burn, or misfire in a neighboring cylinder. A pressure sensor coupled to a cylinder exhaust port is used to sample exhaust pressure pulsations over a cylinder exhaust valve event, and accurately estimate an amount of residuals generated in and released from the cylinder as well as residuals received from the neighboring cylinder. Mitigating actions are performed in the cylinder in accordance before the occurrence of a pre-ignition event.

Abstract: Methods and systems are provided for reducing torque transients experienced when a dedicated EGR cylinder is transitioned in to or out of dedicated EGR mode. During a transition, each of an intake throttle and a wastegate is adjusted in opposing directions. Throttle and wastegate adjustments are coordinated with adjustments to spark timing and intake cam timing to provide sufficient torque reserve for the transition.

Abstract: Methods and systems are provided for adjusting an ignition energy provided to an engine cylinder upon reactivation from a VDE mode of operation. Ignition energy is increased by increasing an ignition coil dwell time and/or an ignition coil strike frequency. The increased ignition energy improves combustion stability during the transition out of the VDE mode of operation.

Abstract: Methods and systems are provided for regulating engine operating parameters such as exhaust gas recirculation (EGR) based on road roughness conditions. Based on increased road roughness estimation, EGR flow rate may be opportunistically raised, enabling NVH associated with elevated EGR levels to be masked by NVH associated with rough road conditions. In addition, purging of fuel vapors from a canister or a crankcase to the engine may be increased while transmission shift schedules may be advanced so as to complete the shift during the rough road condition.

Abstract: Methods and systems are provided for regulating engine operating parameters such as exhaust gas recirculation (EGR) based on road roughness conditions. Based on increased road roughness estimation, EGR flow rate may be opportunistically raised, enabling NVH associated with elevated EGR levels to be masked by NVH associated with rough road conditions. In addition, purging of fuel vapors from a canister or a crankcase to the engine may be increased while transmission shift schedules may be advanced so as to complete the shift during the rough road condition.

Abstract: Methods and systems are provided for improving engine knock tolerance, in particular when rapidly ramping in LP-EGR from low levels of EGR. Until a desired LP-EGR rate is achieved, fuel may be delivered as a split injection with at least an intake stroke injection and a compression stroke injection to compensate for the transport delay in EGR filling the intake system. Subsequently, single fuel injection may be resumed.

Abstract: Methods and systems are provided for reducing corrosion of a charge air cooler and reducing engine misfire due to condensate formation. In response to charge air cooler outlet temperature, electric fan operation and grille shutter opening is adjusted. Electric fan operation and grille shutter opening may also be controlled in response to vehicle operating conditions.

Abstract: Methods and systems are provided for performing mitigating actions in response to detecting a fuel injector leak. In one example, a method may include in response to detecting a fuel injector leak, performing first high pressure mitigating actions including increasing a fuel rail pressure, increasing a pulse width delivered to the leaking fuel injector, and commanding fuel injection during compression stroke; in response to the first mitigating actions not reducing the leak below a threshold rate, performing second high pressure mitigating actions including increasing the fuel rail pressure, increasing the pulse width delivered to the leaking injector, and commanding fuel injection during intake stroke for a cylinder receiving fuel from the leaking injector; and in response to the second mitigating actions not reducing the leak below the threshold rate, reducing the fuel rail pressure, and commanding intake stroke fuel injection to all cylinders.

Abstract: Methods and systems are provided for reducing late burn induced cylinder pre-ignition events. Forced entry of residuals from a late burning cylinder into a neighboring cylinder may be detected based on engine block vibrations sensed in a window during an open exhaust valve of the late burning cylinder. In response to the entry of residuals, a pre-ignition mitigating action, such as fuel enrichment or deactivation, is performed in the neighboring cylinder.

Abstract: Methods and systems are provided for reducing corrosion of a charge air cooler and preventing engine misfire due to condensate formation. In response to an engine controller determining a condensate forming location within a charge air cooler, a grille shutter system is adjusted, moving the condensate region to a different location in the charge air cooler. Grille shutter orientation may also be controlled in response to vehicle operating conditions and condensate-forming weather conditions.

Abstract: Methods and systems are provided for performing a multiple gear downshift of a transmission gear by transiently operating in an intermediate gear. In response to ambient humidity and a condensate level in a charge air cooler, the transmission gear may be downshifted from a higher gear to an intermediate gear, and then to a requested lower gear. Downshifting through an intermediate gear may also be controlled based on the gear shift request.

Abstract: Methods and systems are provided for addressing pre-ignition that may be induced in response to actions taken to mitigate a cylinder misfire. An amount of engine load limiting applied may be adjusted to reduce the likelihood pre-ignition while also addressing component over-temperature issues. By limiting an engine load while shutting off fuel in a misfiring cylinder, and while combusting a lean air-fuel mixture in the remaining cylinders, pre-ignition induced by the misfire-mitigating lean combustion conditions can be reduced.

Abstract: Methods and systems are provided for coordinating cylinder deactivation adjustments with changes to individual cylinder piston displacement. In doing do, the benefits of variable displacement and variable compression ratio may be synergized. An engine can be operated with some cylinders deactivated while active cylinders operate with knock addressed while spark timing is at MBT for a longer duration.

Abstract: Methods and systems are provided for enriching an engine cylinder in response to an indication of pre-ignition. The cylinder is enriched by initially increasing a proportion of fuel delivered to the cylinder via a port injector on an open intake valve event. The cylinder is then continued to be enriched by increasing a proportion of fuel delivered to the cylinder via a direct injector.