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The purpose of this paper is to design an integrated guidance and control design for a formation flight of four unmanned aerial vehicles to follow a moving ground target.

The guidance law is based on the line‐of‐sight. The control is optimal. The guidance law is integrated with the optimal control law and is applied to a linear dynamic model.

The theoretical results are supported by the numerical simulations that illustrate a coordinated encirclement of a ground maneuvering target.

A linear dynamic UAV model and a liner engine model were employed.

This is expected to provide efficient coordination technique required in many civilian circular formation UAV applications; also the technique can be used to provide a safe environment required for the civil applications.

The research will facilitate the deployment of autonomous unmanned aircraft systems in various civilian applications such as border monitoring.

The research addresses the challenges of coordination of multiple unmanned aerial vehicles in a circular formation using an integrated optimal control technique with line‐of‐sight guidance.

This paper aims to investigate the problem of on-line orbit planning and guidance for an advanced upper stage.

The double impulse optimal transfer orbit is planned by the Lambert algorithm and the improved particle swarm optimization (IPSO) method, which can reduce the total velocity increment of the transfer orbit. More specially, a simplified formula is developed to obtain the working time of the main engine for two phases of flight based on the theorem of impulse. Subsequently, the true anomalies of the start position and the end position for both two phases are planned by the Newton iterative algorithm and the Kepler equation. Finally, the first phase of flight is guided by a novel iterative guidance (NIG) law based on the true anomaly update with respect to the geometrical relationship. Also, a completely analytical powered explicit guidance (APEG) law is presented to realize orbital injection for the second phase of flight.

Simulations including Monte Carlo and three typical orbit transfer missions are carried out to demonstrate the efficiency of the proposed scheme.

A novel on-line orbit planning algorithm is developed based on the Lambert problem, IPSO optimization method and Newton iterative algorithm. The NIG and APEG are presented to realize the designed transfer orbit for the first and second phases of flight. Both two guidance laws achieve higher orbit injection accuracies than traditional guidance laws.

The purpose of this paper is to propose a supervisory command‐to‐line‐of‐sight guidance law with lead angle which keeps the missile flight within the tracking beam.

A nonlinear supervisory controller is designed and coupled with the main sliding mode controller in the form of an additional control signal. The supervisory control signal is activated when the beam angle constraint goes to be violated. Initially a supervisory controller is designed using nonlinear control theory. Subsequently the main tracking controller is designed using sliding mode approach which forces the missile to fly along the desired line‐of‐sight. The stability of the supervisory controller coupled with the main controller is proved in the Lyapunov sense.

There exists a major drawback with the lead angle method of guidance, which is a high probability of flying out of the beam. The proposed supervisory controller has successfully overcome this deficiency. Thus, a better performance has been achieved.

The proposed guidance scheme can be applied to tactical surface to air missiles. Additionally the idea of supervisory controller can be applied to any similar control problem where there are some constrains over the states of the system.

The idea of supervisory controller has not been applied to the problem of command‐to‐line‐of‐sight guidance law. This paper utilizes and extends the idea of supervisory controller design to cases when a special state is to be supervised while considering the effect of external disturbances.

A substantial amount of research argues that built environmental interventions can improve the outcomes of patients and other users of healthcare facilities, supporting the concept of evidence-based design (EBD). However, the sources of such evidence and its flow into healthcare design are less well understood. This paper aims to provide insights to both the sources and flow of EBD used in three healthcare projects, to reveal practicalities of use and the relationships between them in practice.

Three healthcare case study projects provided empirical data on the design of a number of different elements. Inductive thematic analysis was used to identify the source and flow of evidence used in this design, which was subsequently quantised to reveal the dominant patterns therein.

Healthcare design teams use evidence from various sources, the knowledge and experience of the members of the design team being the most common due to both ease of access and thus flow. Practice-based research and peer-reviewed published research flow both directly and indirectly into the design process, whilst collaborations with researchers and research institutions nurture the credibility of the latter.

The findings can be used to enhance activities that aim to design, conduct and disseminate future EBD research to improve their flow to healthcare designers.

This research contributes to understandings of EBD by exploring the flow of research from various sources in conflation and within real-life environments.

The purpose of this paper is to present a novel guidance law that is able to control the impact time while the seeker’s field of view (FOV) is constrained.

The new guidance law is derived from the framework of Lyapunov stability theory to ensure interception at the desired impact time. A time-varying guidance gain scheme is proposed based on the analysis of the convergence time of impact time error, where finite-time stability theory is used. The circular trajectory assumption is adopted for the derivation of accurate analytical estimation of time-to-go. The seeker’s FOV constraint, along with missile acceleration constraint, is considered during guidance law design, and a switching strategy to satisfy it is designed.

The proposed guidance law can drive missile to intercept stationary target at the desired impact time, as well as satisfies seeker’s FOV and missile acceleration constraints during engagement. Simulation results show that the proposed guidance law could provide robustness against different engagement scenarios and autopilot lag.

The presented guidance law lays a foundation for using cooperative strategies, such as simultaneous attack.

This paper presents further study on the impact time control problem considering the seeker’s FOV constraint, which conforms better to reality.

To study the application of three‐dimensional differential geometric (DG) guidance commands to a realistic missile defense engagement, and the application of the Newton's iterative algorithm to DG guidance problems.

The classical differential geometry theory is introduced firstly to transform all the variables in DG guidance commands from an arc length system to the time domain. Then, an algorithm for the angle‐of‐attack and the sideslip angle is developed by assuming the guidance curvature command and guidance torsion command equal to its corresponding value of current trajectory. Furthermore, Newton's iteration is utilized to develop iterative solution of the stated algorithm and the two‐dimensional DG guidance system so as to facilitate easy computation of the angle‐of‐attack and the sideslip angle, which are formulated to satisfy the DG guidance law.

DG guidance law is viable and effective in the realistic missile defense engagement, and it is shown to be a generalization of gain‐varying proportional navigation (PN) guidance law and performs better than the classical PN guidance law in the case of intercepting a maneuvering target. Moreover, Newton's iterative algorithm has sufficient accuracy for DG guidance problem.

Provides further study on DG guidance problem associated with its iterative solution.

The aim of this study is to design a guidance method to generate a smoother and feasible gliding reentry trajectory, a highly constrained problem by formalizing the control variables profile.

A novel accelerated fractional-order particle swarm optimization (FAPSO) method is proposed for velocity updates to design the guidance method for gliding reentry flight vehicles with fixed final energy.

By using the common aero vehicle as a test case for the simulation purpose, it is found that during the initial phase of the longitudinal guidance, there are oscillations in the state parameters which cause to violate the path constraints. For the glide phase of the longitudinal guidance, the path constraints have higher values because of the increase in the atmosphere density.

The violation in the path constraints may compromise the flight vehicle safety, whereas the enforcement assures the flight safety by flying it within the reentry corridor.

An oscillation suppression scheme is proposed by using the FAPSO method during the initial phase of the reentry flight, which smooths the trajectory and enforces the path constraints partially. To enforce the path constraints strictly in the glide phase, ultimately, another scheme by using the FAPSO method is proposed. The simulation results show that the proposed algorithm is efficient to achieve better convergence and accuracy for nominal as well as dispersed conditions.

Traditional skid-to-turn (STT) missile control mode is adopted mostly, but with the improvement of requirements for mobility and the emergence of new aerodynamic layout, a bank-to-turn (BTT) control mode gradually shows a greater advantage. However, the BTT missile also has certain defects, for example, when attacking against a maneuvering target and at the last section of guidance, the maximum lifting surface position of the missile needs to be adjusted frequently, thereby increasing the difficulty of control as well as introducing high-frequency noise.

Based on respective characteristics of the two control modes, this paper puts forward a hybrid autopilot design method based on nonlinear dynamic inversion. Firstly, the method converts overload instructions into corresponding angle instructions through the design of hybrid control guidance logic; secondly, based on the nonlinear dynamic inversion algorithm and combined with the fast-changing circuit/slowly changing circuit, a hybrid controller is designed; finally, combined with the missile mathematical model and actuator, it forms a autopilot design closed loop.

The simulation result shows that the non-linear dynamic inverse-based BTT/STT hybrid controller can input a track command well, normal overload and roll angle tracking performance have more advantages than the hybrid controller designed on the basis of classical control method in terms of overshooting and hysteretic characteristics.

The paper puts forward a new BTT/STT hybrid control method which has both the high mobile ability of the BTT missile and the precise control ability of the STT missile, which can adapt to the more complicated fighting environment. And, the method can effectively weaken the impact of the transformation of the control mode on the system.

Singapore is transforming from a “garden city” to a “city‐in‐a‐garden”. Designing for safety is recognized by researchers and some governments as a best practice in facilitating eventual worker safety within the built environment. The purpose of undertaking this research was to understand and describe the status of safe design for skyrise greenery in Singapore.

A total of 41 rooftop and vertical greenery systems were observed with a focus on access, fall from height, and planting considerations.

Rooftop greenery systems in Singapore were found to be adhering to safe design principles. Vertical and ledge greenery systems, on the other hand, are newer arrangements and were found to be in need of design for safety guidance.

The results add to the body of knowledge in the area of safe design and skyrise greenery and will aid those seeking to understand from a policy and practice perspective.

Despite the importance of the service design process, existing prototyping methods still have technical limitations, thus hampering the development of realistic service-experience simulations that can effectively reproduce service delivery situations and environments. In this study, a service-prototyping method based on 3D virtual reality (VR) technologies, the physical environment of a test bed, and related standard management procedures are described. In addition, a service-prototyping process for a servicescape is proposed based on a case study of an actual duty-free shop. The paper aims to discuss these issues.

The study adopts a qualitative approach, using case studies to undertake a design and improvement plans for brand guidance structures for the brand observation convenience of customers in a duty-free shop.

The findings of the study suggested environmental components and concept of 3D VR based test bed as an effective tool at the stage of service prototyping the core of new service development (NSD), and introduced practical methods for service prototyping in actual duty-free shop. The case study is significant due to the fact that it proved validity and practicality of the methods applied to service prototyping topic derivation and test process through target service analysis rather than optimal alternative selection.

This study emphasizes the importance of prototyping during NSD and the value of the service prototyping test bed for practical use. It also proposes guidelines for the establishment and management of the test bed.

In terms of service design research, this study also presented detailed operating procedures and methods through the new concept and in-depth case study of service prototyping using 3D VR technology.