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The purpose of this paper is to test the performance of the control system developed for the helicopter automatic approach and landing on the moving vessel deck, when different values of backlashes are applied to the four control actuators.

The system consists of automatic control algorithm based on the linear quadratic regulator and the vessel motion prediction algorithm based on autoregressive method with parameters calculated using Burg’s method. Necessary navigation data is provided by on-board inertial navigation system/Global Positioning System. Calculated control commands are executed by four electromechanical actuators. Performance of the mission, which is based on selected procedure of approach and landing of the helicopter on the moving vessel deck, is analyzed taking into account different values of backlashes applied to the actuators.

In this paper, a description of the control system dedicated for automatic approach and landing of the helicopter on the moving vessel deck is shown. Necessary information about helicopter dynamic model, control system and vessel motion model is included. Tests showing influence of actuator backlashes on the mission performance are presented.

The developed control methodology can be adapted for selected helicopter and used in prospective development of an automatic flight control system (AFCS) or in a simulator. The system can be used to define in which conditions helicopter can perform safe and successful automatic approach and landing on a moving vessel deck.

In this paper, an integrated control system is presented; influence of the control actuator backlashes on the mission performance is analyzed.

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).

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.

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.

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.

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.

The purpose of this paper is to discuss a numerical study of the flow over a wing representative of a large civil aircraft at cruise condition. For each Mach number considered, the numerical simulations indicate that critical angle of attack exists where the separated region increases in size and begins to oscillate. This phenomenon, known as transonic shock buffet, is reproduced by the unsteady simulation and much information can be extracted analysing location, amplitude and frequency content of the unsteadiness.

Reynolds-averaged Navier-Stokes simulations are conducted on a half wing-body configuration, at different Mach numbers and angles of attack. Different turbulence models are considered, and both steady-state results and time-accurate simulations are discussed.

The high number of cases presented in this study allows the creation of a database which, to the authors’ knowledge, has not been documented in literature before. The results indicate that, while high-fidelity approaches can improve the quality of the results, the URANS approach is capable of describing the main features of the buffet phenomenon.

The presence of a turbulence model, despite allowing the description of the main unsteady phenomenon, might be insufficient to fully characterise the unsteadiness present in a transonic flow over a half wing-body configuration. Therefore, researchers are encouraged to verify by means of experimental investigation or high-fidelity approach the results issued from a Reynolds-averaged Navier-Stokes equations.

The results presented clearly indicate that, despite what proposed in recent research papers, transonic buffet can be described by means of time-accurate Reynolds-averaged Navier-Stokes equations. Such an approach is popular in the aeronautical industry because of its reduced costs, and could be used for wing design.

In this paper, the authors used a classical approach to tackle the known problem of transonic buffet in three-dimensional configurations. The large number of results presented can be used as a database for future numerical simulations and experiments, and allow to describe the flow-physics of the buffet unsteadiness on a half wing-body configuration.

The university is changing. Its social role is growing in diversity and complexity. In a knowledge-based society, there is a huge public expectation in the results and impacts of the university’s activities. Its traditional roles – training and qualification of individuals and production of new knowledge – are no longer valid. As a result of university–industry interactions, policy-making began to give additional significance to the role of the university in regional development, mainly motivated by shining examples of success in transferring scientific knowledge to valuable innovation, many through academic entrepreneurship. This change in the role of the university is reflected not only in the mode of knowledge production, which became more transdisciplinary and applied, but also in the active engagement of different institutional spheres, the university, the firm, the government, and end-users, creating new hybrid and overlapping areas for the governance of innovative dynamics. This chapter defines and analyses the position of the university in contemporary society as a socially legitimised institution for the production of knowledge and innovation. Three different theoretical traditions – Actor–Network Theory, Stakeholder Theory and territorial innovation models – inspire the analysis of 15 in-depth interviews with key actors in their local innovation system and knowledge networks around the University of Huelva (Andalusia, Spain). The main conclusions suggest that the university today faces a huge challenge in responding to the expectations that society places on it.

IT IS a widely admitted fact that a large proportion of inventions come from Britain. We have always been an innovative group of nations (for we are not referring to England alone. Scotland and Wales have done more than their share,) but far too often the exploitation has enriched firms and countries far removed from these islands.

Sheen Instruments Ltd., the exclusive UK representatives for BYK‐Gardner, announce the introduction of Wave‐Scan, a portable laser scanning instrument for the objective assessment of orange peel.

When reading viscosity measurements of hot melts and liquids at elevated tempeatures, maintaining accurate temperature control—that is consistent from sample to sample — has always posed a difficult problem.

In May 1978 the Paint R.A., Waldegrave Rd, Teddington, Middx TW11 8LD, published a Directory of Paint and Pretreatment Products aimed to assist industrial paint users to locate sources of paints of all types. A complementary Finishing Equipment and Processes Directory is now available. Preparation of the two directories is one part of a technology transfer contract for the Department of Industry's Chemicals and Minerals Requirements Board which aims to help UK manufacturers to improve their product finishing through optimum use of existing knowledge, materials and methods.

Studies suggest that there is a shortage of minorities entering the professions of science, technology, engineering, and mathematics (STEM). This is especially the case with African American males. Several factors that impact this phenomenon are discussed in this chapter, but chiefly the impact of test anxiety and test bias on the absence of African American men in STEM. These factors are significant because society dictates that we embrace the use of tests to determine ability. However, many individuals, including African American males, suffer from test anxiety and are victims of test bias. Science, technology, engineering, mathematics are areas that rely heavily on tests results. Therefore, the impact of test anxiety and test bias as a prohibitory method of denying access to minorities, especially African American males, is worthy of investigation and discussion. The chapter explores this relationship of test anxiety and test bias to the absence of African American males in STEM. It also looks at the importance of historically Black colleges and universities in adding African American males to STEM fields. Plausible solutions to the problem are also provided.