Flap failure and aircraft controllability: Developments in asymmetry monitoring techniques

Borello, Lorenzo; Villero, Giuseppe; Vedova, Matteo Davide Lorenzo Dalla

doi:10.1007/s12206-014-1027-0

Cited by 20 publications

(25 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another consequence of the mechanical wearing of moving components is the increase of the transmission backlash. When a relatively large mechanical play interacts with the actuator feedback logic, the stability and stiffness of the system are compromised, as highlighted by [25]. The main failure modes affecting BLDC motors are partial stator short circuit and rotor eccentricity due to the degradation of bearings.…”

Section: Ema Degradations and Fault Modesmentioning

confidence: 99%

“…The EMA Dynamical Model block simulates the mechanical effects within the motor and the transmission, by means of a single degree of freedom MCK model. Additionally, this model accounts for several non-linear effects that characterize the dynamic response of the mechanical system, such as dry friction [23,24], backlash [25], and mechanical end-stops [26].…”

mentioning

confidence: 99%

“…accounts for several non-linear effects that characterize the dynamic response of the mechanical system, such as dry friction [23,24], backlash [25], and mechanical end-stops [26]. 4.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Model-Based Fault Detection and Identification for Prognostics of Electromechanical Actuators Using Genetic Algorithms

et al. 2019

Self Cite

View full text Add to dashboard Cite

Traditional hydraulic servomechanisms for aircraft control surfaces are being gradually replaced by newer technologies, such as Electro-Mechanical Actuators (EMAs). Since field data about reliability of EMAs are not available due to their recent adoption, their failure modes are not fully understood yet; therefore, an effective prognostic tool could help detect incipient failures of the flight control system, in order to properly schedule maintenance interventions and replacement of the actuators. A twofold benefit would be achieved: Safety would be improved by avoiding the aircraft to fly with damaged components, and replacement of still functional components would be prevented, reducing maintenance costs. However, EMA prognostic presents a challenge due to the complexity and to the multi-disciplinary nature of the monitored systems. We propose a model-based fault detection and isolation (FDI) method, employing a Genetic Algorithm (GA) to identify failure precursors before the performance of the system starts being compromised. Four different failure modes are considered: dry friction, backlash, partial coil short circuit, and controller gain drift. The method presented in this work is able to deal with the challenge leveraging the system design knowledge in a more effective way than data-driven strategies, and requires less experimental data. To test the proposed tool, a simulated test rig was developed. Two numerical models of the EMA were implemented with different level of detail: A high fidelity model provided the data of the faulty actuator to be analyzed, while a simpler one, computationally lighter but accurate enough to simulate the considered fault modes, was executed iteratively by the GA. The results showed good robustness and precision, allowing the early identification of a system malfunctioning with few false positives or missed failures.Aerospace 2019, 6, 94 2 of 15 occurrence of a failure before the scheduled substitution of the interested system. Monitoring the behavior of an actuator could enable to detect the early signs of different progressive faults, in order to timely correct them. If a tool would be available with a high grade of robustness to isolate those incipient faults, most failure modes of the flight control system could be identified before they start affecting the performance of the system in terms of dynamical response, stability, stall force, or positioning accuracy. The discipline aimed to this purpose is called Prognostics and Health Management (PHM) (as reported in [1]). The application of PHM strategies involves the analysis of functional parameters of the system in form of electrical signals: for this reason, the use of electrical actuators someway represents an advantage, because no conversion of the signals (and therefore no additional sensors) is needed. Due to the complexity and to the multi-disciplinary nature of the monitored systems, the FDI task on EMA systems is particularly challenging, since several failure modes interact and an acceptable accuracy is hardly ac...

show abstract

Section: Ema Degradations and Fault Modesmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Model-Based Fault Detection and Identification for Prognostics of Electromechanical Actuators Using Genetic Algorithms

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…The relative merits of the three solutions (non-reversible actuators, reversible actuators with wingtip brakes, reversible actuators with irreversibility brakes) and which of the three is the better solution is widely described in [1][2][3]. Nowadays the most widely used architecture for high-medium performance aircrafts employs the reversible actuators with wingtip brakes and centrally located PDU (dual motor type for operational reliability) since it is cheaper and more efficient, so this architecture is considered in the present work.…”

Section: Secondary Flights Control Systemmentioning

confidence: 99%

A new active asymmetry monitoring and control technique applied to critical aircraft flap control system failures

2019

View full text Add to dashboard Cite

Asymmetry limitation requirements between left and right wing flap surfaces play an important role in the design of the implementation of the secondary flight control system of modern airplanes. In fact, especially in the case of sudden breaking of one of the torsion bars of the flap transmission line, the huge asymmetries that can rapidly develop could compromise the lateral-directional controllability of the whole aircraft (up to cause catastrophic occurrences). Therefore, in order to guarantee the aircraft safety (especially during take-off and landing flight phase in which the effects of asymmetries could generate uncontrollable aircraft attitudes), it is mandatory to timely detect and neutralize these asymmetries. The current monitoring techniques generally evaluate the differential angular position between left and right surfaces and, in most the events, limit the Flaps Control System (FCS) asymmetries, but in severe fault conditions (e.g. under very high aerodynamic loads), unacceptable asymmetries could be generated, compromising the controllability of the aircraft. To this purpose, in this paper the authors propose a new active monitoring and control technique capable of detecting the increasing angular error between the different flap surfaces and that, after stopping the whole actuation system, acts on the portion of the actuation line still connected to the PDU to minimize the FCS asymmetries.

show abstract

“…This experimental technology to develop a robust control algorithm is an alternative to numerical models [11]. Additionally, this concept of control with offset can support situations during failure (asymmetry load-non-symmetrical elastic hysteresis of flexible joint) with on-line offset value changing.…”

Section: Nonlinearity In Electro Hydraulic Actuator Systemmentioning

confidence: 99%

Nonlinearities in Control Description and Design of an Electro Hydraulic Actuator for Flexible Nozzle Thrust Vector Control

Nauparac¹,

Pršić

Miloš

2018

Actuators

View full text Add to dashboard Cite

This paper presents all the significant nonlinearities that exist in the description of an electro hydraulic actuator for flexible nozzle thrust vector control. Starting from practical possibilities of the theory of a nonlinear system (which are based on the analyses of one nonlinearity or one equivalent nonlinearity in the proximity of the linear description of an actuator), this paper explores the possibilities of additional analyses of a nonlinear electro hydraulic actuator for flexible nozzle thrust vector control. These explored possibilities can provide information that is useful for the design of the control algorithm, as well as for the general design of a flexible nozzle and actuator system.

show abstract

Flap failure and aircraft controllability: Developments in asymmetry monitoring techniques

Cited by 20 publications

References 4 publications

Model-Based Fault Detection and Identification for Prognostics of Electromechanical Actuators Using Genetic Algorithms

Model-Based Fault Detection and Identification for Prognostics of Electromechanical Actuators Using Genetic Algorithms

A new active asymmetry monitoring and control technique applied to critical aircraft flap control system failures

Nonlinearities in Control Description and Design of an Electro Hydraulic Actuator for Flexible Nozzle Thrust Vector Control

Contact Info

Product

Resources

About