The review concludes by summarising the scope for further research in the area of redundancy strategies and approaches for integrated vehicle health management. The various issues in design optimisation of EHA for flight application are elaborated. It is treated as a mechatronic system and review of publications related to multi-disciplinary modelling/simulation approaches have been presented in the paper. EHA is a multi-domain system consisting of electrical, mechanical, hydraulic and control system. The paper also includes control strategies, reliability and fault tolerant techniques along with the thermal aspects of the EHA system. It examines the advantages, limitations and possible configurations of the EHA. This paper reviews literature (in English language only) published in the period 1990 to 2015 and available at major technical university libraries or e-journals. EHA has become an important part of modern flight control systems due to the increased efficiency, reduced leakages and lower overall weight compared to conventional hydraulic systems. These utility functions require system control in order to fulfil the various tasks in the right sequence, for example to open doors, deploy mechanism and lock the doors in the open position.Electro Hydrostatic Actuator (EHA) is an emerging aerospace technology that aims at replacing centralised hydraulic system by a self-contained and localised direct drive actuator system. System controlĪircraft and helicopters use hydraulic circuits to power different systems like flight control actuation, landing gear extension and retraction or landing gear door actuation. They are used on board different aircraft like fighters and helicopters. These piston pumps and motors are used in high reliability applications like electro-hydraulic actuators or high lift systems on commercial airplanes and military transport aircraft.Įlectrically driven pumps are also part of the Liebherr product portfolio. Liebherr develops and manufactures hydraulic pumps and motors ranging from 1,500 psi over 3,000 psi up to 5,000 psi. Liebherr-Aerospace is also capable to develop Electrical Thrust Reverser Actuation Systems, using electro-mechanical actuators instead of hydraulic actuators. The system needs to be designed in a way that a deployment of the system during flight is impossible. Thrust Reverser Actuation Systems are considered as being safety critical. A typical hydraulically actuated TRAS comprises door actuators, locking/unlocking actuators, hydraulic valve blocks, check valves, position sensors and hydraulic control units. Liebherr-Aerospace provides the Thrust Reverser Actuation System (TRAS) to move the thrust reverser doors when activated by the pilot. This helps to reduce the stress on the landing gear brakes and constitutes a major safety feature for landing in bad weather conditions, when the aircraft brakes might no longer be effective enough to bring the aircraft to a stop.
The Liebherr Ruddervator Control Systems supports the operation of the A330 MRTT boom refueling system.Ĭommercial aircraft engines are equipped with a thrust reverser helping to decelerate the aircraft after touch down by reversing the direction of the exhaust stream. The primary flight control actuators of fly-by-wire flight control systems of existing aircraft are electrohydraulic servoactuators with a typical. The most advanced air refueling systems, used on A330 MRTT, A400M, KC-46 or KC-390 are equipped with Liebherr Hose Drum Drive Systems.
The world’s first commercial aircraft featuring folding wingtips, the Boeing B777X, is equipped with a hydraulically driven folding mechanism made by Liebherr, including a power drive unit, geared rotary actuators and latch/locking actuators. Latch and Locking systems include landing gear up-locks and ramp door latch actuators for military transport aircraft. Liebherr also is able to supply complete customized door actuation systems featuring actuators, control manifolds and system electronic controllers with embedded software. The HPU circuit contains a reservoir, two electric motor-hydraulic pump units, filters, hoses, fittings, and more. Generally, the HPU will supply hydraulic power for the operation of connected systems in the circuit. We develop and manufacture actuators to open and close doors for applications like cargo doors, weapon bay doors or landing gear doors. The hydraulic power unit (HPU) and a motion base are the two major hydraulic subsystems in the flight simulator. Our product portfolio ranges from door actuators, latch and locking systems up to complex actuation systems for wing tip folding or air refueling. Liebherr supplies a wide variety of utility actuation systems for multiple applications. Generating- and profile-grinding machinesĮlectric drive systems for off-highway applicationsīuilding construction and civil engineering Heavy Lift Handling in Rostock, Germany - TCC 78000