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Open Access
Article
Publication date: 2 June 2023

Sebastian Topczewski and Przemyslaw Bibik

The purpose of this study is to test the performance of the designed automatic control system based on the Linear Quadratic Regulator (LQR) and Linear Quadratic Gaussian (LQG…

Abstract

Purpose

The purpose of this study is to test the performance of the designed automatic control system based on the Linear Quadratic Regulator (LQR) and Linear Quadratic Gaussian (LQG) algorithms during landing of the helicopter on the ship deck. This paper is a further development of the series based on Topczewski et al. (2020).

Design/methodology/approach

The system consists of two automatic control algorithms based on LQR and the LQG. It is integrated with the ship motion prediction system based on autoregressive algorithm with parameters calculated using Burg’s method. It is assumed that the source of necessary navigation data is integrated Inertial Navigation System with Global Positioning System. Landing of the helicopter on the ship deck is performed in automatic way, based on the preselected procedure. Performance of the control system is analyzed when all necessary navigation data is available for the system and in case when one of the parameters is unavailable during performing the procedure.

Findings

In this paper, description of the designed control system developed for performing the approach and landing of the helicopter using selected procedure is presented. Helicopter dynamic model is validated using the manufacturer data and by test pilots, overview is presented. Necessary information about ship motion model is also included. Tests showing mission performance while using LQR and LQG algorithms applied to the control system are presented and analyzed, taking into account both situations when full navigation data is available/unavailable for the control system.

Practical implications

Results of the system performance analyses can be used for selection of the proper control methodology for prospective helicopters autopilots. Furthermore, the system can be used to analyze the mission safety when information about one of the navigation parameters is identified by the navigation system as unavailable or incorrect and therefore unavailable during landing on the ship deck.

Originality/value

In this paper, control system dedicated for the automatic landing of the helicopter on the ship deck, based on two different control algorithms is presented. Influence of lack of information about one of the navigation parameters on the mission performance is analyzed.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 December 2002

Yuan Su and Yihua Cao

As compared with the maneuvering flight studies for single main rotor helicopters, the corresponding studies for coaxial rotor helicopters are relatively poor. In this paper, the…

1456

Abstract

As compared with the maneuvering flight studies for single main rotor helicopters, the corresponding studies for coaxial rotor helicopters are relatively poor. In this paper, the maneuvering flight governing equations for coaxial rotor helicopters is established. By introducing induced velocity interference factor analysis, the coaxial rotor aerodynamic interference can be taken into account. With the combination of coaxial rotor helicopter control features and nonlinear inverse simulation technique, the governing equations for maneuvering flight can be solved so as to determine helicopter control input, control force and moment, and helicopter body attitudes which are needed for performing a specified maneuver. Good results of the sample calculations of level turn and lateral jink maneuvers are obtained and simply analyzed.

Details

Aircraft Engineering and Aerospace Technology, vol. 74 no. 6
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 30 September 2014

Victor Zakharchenko and Alexander Lukovnikov

– The purpose of the work is to carry out analysis of the possibilities and estimation of electric drive efficiency for rotors of helicopter propulsion systems (PS).

Abstract

Purpose

The purpose of the work is to carry out analysis of the possibilities and estimation of electric drive efficiency for rotors of helicopter propulsion systems (PS).

Design/methodology/approach

Methodology and comprehensive multidisciplinary technology for efficiency estimation of conventional and unconventional architectures PS on rotorcraft system level at preliminary design phase were developed.

Findings

Application of the approach allow to carry out analysis of hybrid (based on gas turbine and piston engines) and full electrical PS for superlight-, light- and medium-size helicopters.

Practical implications

It was shown what level of electrical technologies improvement may provide positive effect of the using of hybrid and full electrical helicopter PS of different architectures.

Originality/value

Close matching of helicopter and engine design and calculation aspects, as well as possibilities to use the external (experimental) performances of engine components, whole PS and helicopter aerodynamic performance, are the distinctive features of proposed technology and methodology.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 86 no. 6
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 April 2001

Yuan Su and Yihua Cao

Studies of the hingeless rotor helicopter dynamic stability and control laws are conducted. A new method is given for the calculation of stability and controllability of a…

1362

Abstract

Studies of the hingeless rotor helicopter dynamic stability and control laws are conducted. A new method is given for the calculation of stability and controllability of a helicopter in flight condition with lateral velocity. First, the rotary wing dynamic model considered is the one of flap‐pitch (including the elastic deformation of control system) – torsion coupling. The induced velocity non‐uniform distribution derived from vortex theory is taken into account. Then, according to the established motion model of the helicopter, the effects of induced velocity distribution, flap‐pitch‐torsion coupling and lateral velocity on the stability and controllability of the helicopter are analyzed. Based on the analyses of dynamic stability of the helicopter, the unstable mode and the necessity of installation of stability augmentation system (SAS) are recognized. Finally, the control laws of SAS for helicopter pitching, rolling and yawing motions are presented. After establishing helicopter flight control state equations, the performance analyses and step response simulation for helicopter SAS are carried out.

Details

Aircraft Engineering and Aerospace Technology, vol. 73 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Book part
Publication date: 14 November 2022

Mackenzie Mountford and Faye M. Vento

Children's marginalisation in research limits their opportunities to create meaningful social change. This project explored children's meaningful participation in Participatory…

Abstract

Children's marginalisation in research limits their opportunities to create meaningful social change. This project explored children's meaningful participation in Participatory Action Research as a tool to empower children as change makers. An adult and child co-researcher collaborated to conduct a literature review on a social issue chosen by the child: helicopter parenting. Highlighting that children and adults have access to different knowledge based on their status in society, the co-researchers wrote about helicopter parenting from three different perspectives: media, psychology and childhood studies. Through a reflection on the research process, the co-researchers offer insight into the impact of mutual relationships, power imbalances, and emotions on children's meaningful participation in research. They also present the value of children's voices in research and research as a learning opportunity for adults and children. Ultimately, the co-researchers aim to challenge readers to reflect on creating more equitable research practices with children to enhance children's opportunities to make change through research.

Details

Establishing Child Centred Practice in a Changing World, Part A
Type: Book
ISBN: 978-1-80117-407-7

Keywords

Article
Publication date: 11 April 2023

JingHui Deng, Jinhe Chen and ZhengZhong Wang

The paper aims to establish a comprehensive optimization analysis model for a helicopter roll on the ground and take off based on optimal control method. The trajectory and…

Abstract

Purpose

The paper aims to establish a comprehensive optimization analysis model for a helicopter roll on the ground and take off based on optimal control method. The trajectory and control of the entire process are studied, and the key factors affecting the helicopter takeoff distance are analyzed.

Design/methodology/approach

First, based on the equivalent stiffness and damping, the landing gear model is established, and a six-degree-of-freedom helicopter model is formed. Then, the simulation of the roll-on takeoff is transformed into a nonlinear optimal control problem (NOCP). Meanwhile, a hybrid single-multiple shooting method-based transcription process is used for discretizing the problem, leading to a finite nonlinear programming model, which is solved by sequential quadratic programming. Finally, the process was calculated and compared with flight test data, which verified the feasibility of the NOCP. The influence of takeoff weight, takeoff power and liftoff airspeed on the takeoff distance of the helicopter was analyzed.

Findings

The results show that the takeoff weight can be increased by 17% under the maximum takeoff power, which is roll-on takeoff at an altitude of 0 m. When the helicopter takes off with the maximum weight at an altitude of 5000 m, the liftoff airspeed should be over 49.2 km/h.

Originality/value

The novelty of this paper lies in the comprehensive consideration of helicopter taxiing and taking-off phases, and the application of optimal control theory to establish a comprehensive analysis model, which can quickly analyze the maximum takeoff weight, takeoff distance, optimal liftoff speed and so on. Meanwhile, the method is verified based on the flight data.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Content available
Article
Publication date: 23 May 2023

Russell Nelson, Russell King, Brandon M. McConnell and Kristin Thoney-Barletta

The purpose of this study was to create an air movement operations planning model to rapidly generate air mission request (AMR) assignment and routing courses of action (COA) in…

Abstract

Purpose

The purpose of this study was to create an air movement operations planning model to rapidly generate air mission request (AMR) assignment and routing courses of action (COA) in order to minimize unsupported AMRs, aircraft utilization and routing cost.

Design/methodology/approach

In this paper, the US Army Aviation air movement operations planning problem is modeled as a mixed integer linear program (MILP) as an extension of the dial-a-ride problem (DARP). The paper also introduces a heuristic as an extension of a single-vehicle DARP demand insertion algorithm to generate feasible solutions in a tactically useful time period.

Findings

The MILP model generates optimal solutions for small problems (low numbers of AMRs and small helicopter fleets). The heuristic generates near-optimal feasible solutions for problems of various sizes (up to 100 AMRs and 10 helicopter team fleet size) in near real time.

Research limitations/implications

Due to the inability of the MILP to produce optimal solutions for mid- and large-sized problems, this research is limited in commenting on the heuristic solution quality beyond the numerical experimentation. Additionally, the authors make several simplifying assumptions to generalize the average performance and capabilities of aircraft throughout a flight.

Originality/value

This research is the first to solve the US Army Aviation air movement operations planning problem via a single formulation that incorporates multiple refuel nodes, minimization of unsupported demand by priority level, demand time windows, aircraft team utilization penalties, aircraft team time windows and maximum duration and passenger ride time limits.

Details

Journal of Defense Analytics and Logistics, vol. 7 no. 1
Type: Research Article
ISSN: 2399-6439

Keywords

Article
Publication date: 13 June 2022

Firat Sal

This paper aims to offer a simultaneous design approach for helicopter having swept anhedral blade tip shape and helicopter flight control system (HFCS) to minimize controller…

Abstract

Purpose

This paper aims to offer a simultaneous design approach for helicopter having swept anhedral blade tip shape and helicopter flight control system (HFCS) to minimize controller cost.

Design/methodology/approach

By considering previously stated offer, control-oriented models and a stochastic optimization method are applied to minimize controller cost of the HFCS.

Findings

Using simultaneous design approach for helicopters having blade tip swept and blade tip anhedral causes considerably less control effort than the helicopters not benefiting this related design approach.

Practical implications

Simultaneous design approach for helicopters having blade tip swept and blade tip anhedral is applicable to consider fuel economy.

Originality/value

One important novelty of this paper is using simultaneous approach for determining optimum shape of blade tip swept and anhedral. Another considerable novelty of this paper is also using a stochastic optimization method called simultaneous perturbation stochastic approximation for previously mentioned purpose. In this paper, it is also reached that using simultaneous design approach for swept anhedral helicopter blade tip shape and HFCS causes less control effort than the helicopters not using this approach. This leads to less fuel consumption and green environment.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 18 November 2021

Randy Evans and Katherine A. Karl

This paper aims to examine the ethical foundations of Gen Z individuals by studying the impact of helicopter parenting on moral courage and moral disengagement. In addition, this…

Abstract

Purpose

This paper aims to examine the ethical foundations of Gen Z individuals by studying the impact of helicopter parenting on moral courage and moral disengagement. In addition, this study considers the implications for Millennial generation managers that are likely to be supervising this current generational cohort.

Design/methodology/approach

Hypotheses were tested using a two-wave online survey of 215 undergraduate students.

Findings

Helicopter parenting was associated with lower levels of moral courage and an elevated propensity to morally disengage in a sample of Gen Z individuals. The impact of helicopter parenting on these moral foundations was mediated by the children’s increased desire for continued parental involvement in their lives.

Practical implications

Similar to the Gen Z students surveyed in this study, many Millennials were raised by helicopter parents, thus, it is likely that they are also prone to moral disengagement and low moral courage. Furthermore, Millennial managers will be managing Gen Z workers. Thus, many companies will need to enhance their efforts in providing Millennial managers with business ethics training aimed at developing moral courage and reducing moral disengagement.

Originality/value

This study examines a previously unidentified antecedent of moral courage and moral disengagement

Details

Management Research Review, vol. 45 no. 5
Type: Research Article
ISSN: 2040-8269

Keywords

Article
Publication date: 4 July 2016

Francesco Castelluccio, Luigi Maritano, Salvatore Amoroso and Marco Migliore

This study aims to develop a methodology to compare the feasibility of helicopter and seaplane regular transport of passengers towards destinations across a remote regional…

Abstract

Purpose

This study aims to develop a methodology to compare the feasibility of helicopter and seaplane regular transport of passengers towards destinations across a remote regional tourist context, where a lack of road and rail infrastructure make these alternative forms of air transport competitive.

Design/methodology/approach

The authors use a modal split model identifying the quota of passengers that potentially could utilize these two types of services, determined on the basis of previous studies on air transport demand. A technical analysis regarding transport supply is performed to identify the predominant features that should characterize helicopter/seaplane performances. An optimization model is applied to identify the routes that could overcome the breakeven point considering each of the two means of transport. The paper also takes into account the importance of each type of service and its influence on flight infrastructure costs.

Findings

Helicopter and seaplane services could improve the access for tourists with high values of time. The helicopter transport could capture a market share ranging from 5 to 20 per cent of tourist travel demand (the amphibian seaplane from 1 to 14 per cent). The shuttle services could be profitable especially for those regional origin–destination pairs involving the two major airports and the most UNESCO visited locations such as Agrigento and the Aeolian Archipelago (into the analyzed context of Sicily). The comparison between the two modes of transport shows that the helicopter has best performances and the seaplane has to land/take-off from sea.

Research limitations/implications

The lack of data on the performances of the whole world production of seaplanes and helicopters (such as Russian, Chinese or US old machines) could give a distortion of the result. On the other hand, all mostly used machines in the world at the moment are considered. A survey on the fear of flight and on the choice between the two different forms of air transport could give a more precise result.

Practical implications

From an economic point of view, an operator could choose with more confidence the means of transport to use under different conditions. The activation of passenger services with seaplanes and helicopters can give an impulse to the growth of little operators and to the tourism. So, this study could be a starting point for authorities to plan a regional network of little general aviation airfields and seadromes (located in the great lakes or near the ports) near the major tourist locations. It could make possible to develop a synergic regional commuting traffic involving the seaplane and the helicopter.

Social implications

Seaplanes and helicopters represent the most important means of transport when poor accessibility conditions and need of ready and fast connections coexist, for example, the commuting between airports and remote regions or downtowns with high tourist or business impact. The activation of passenger services with seaplanes and helicopters can give an impulse to the growth of little operators and to the tourism, consequently to the regional accessibility and economy.

Originality/value

There is a lack of studies involving the comparison between seaplanes and helicopters. This study could represent an important means to analyze the parameters that influence the possibility of activation for this kind of services and to find the factors that influence the feasibility of business with the two different machines. The encouraging performances of the flying boat suggest a future development of an innovative model of medium- and/or high-capacity amphibian seaplane dedicated to passenger transport. It should have take-off/landing performances less dependent on the sea state.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 88 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

1 – 10 of over 5000