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The purpose of this paper is to design a solar sail heliocentric transfer orbit which can meet the requirements of control system and capture orbit, and to provide the change of angles for attitude control system.

Aiming at the problem of solar sail heliocentric transfer orbits design, this paper addresses the derivation of analytical optimal control law. The control laws can realize the combination of the control of each orbit element, but they can only give local optimal solution to meet the practical needs of mission. In order to solve this problem and meet the capture orbit and the attitude control system requirements, the modified genetic algorithm based on the analytical control law is introduced.

The algorithm addressed by this paper includes results closer to the global optimization, and also can meet the engineering constraints.

The analytical optimal control law can be applied to the future onboard sail control systems. The blending optimal algorithm is demonstrated to be suitable as a method of preliminary design for solar sail deep space exploration mission.

A blending optimal algorithm combining the analytical control law and genetic algorithm is proposed; the algorithm can search for global optimization based on the local optimal results of analytical control law.

The aim of this paper is to discuss E-sail-based missions (E-sail – electric solar wind sail) towards Venus and Mars. The analysis takes into account the real three-dimensional shape of the starting and arrival orbits and the planetary ephemeris constraints by using the Jet Propulsion Laboratory (JPL) planetary ephemerides model DE405/LE405.

Each mission scenario is parameterized with different values of departure date and spacecraft characteristic acceleration, the latter representing the maximum propulsive acceleration when the Sun–spacecraft distance is 1 au. The transfer trajectories are studied in an optimal framework, using a Gauss pseudospectral method in which the initial guesses for the state and control histories are obtained with a genetic algorithm-based approach.

The paper illustrates the numerical simulations obtained with a spacecraft characteristic acceleration of 1 mm/s², and the results cover a range of launch dates of 17 years for both Earth–Mars and Earth–Venus interplanetary missions. In particular, the numerical results confirm the competitiveness of such a propellantless propulsion system.

A parametric study of the transfer’s flight time corresponding to the optimal departure dates is discussed for different values of the spacecraft characteristic acceleration. The results motivate a further in-depth analysis of the E-sail concept.

This paper extends previous work on optimal trajectories with an E-sail in that the best launch opportunities are investigated. A refined thrust model is also used in all numerical simulations.

The purpose of this paper is to resolve complex nonlinear dynamical problems of the pitching axis of solar sail in body coordinate system compared with inertial coordinate system. And saturation condition of controlled torque of vane in the orbit with big eccentricity ration, uncertainty and external disturbance under complex space background are considered.

The pitch dynamics of the sailcraft in the prescribed elliptic earth orbits is established considering the torques by the control vanes, gravity gradient and offset between the center-of-mass (cm) and center-of-pressure (cp). The maximal torques afforded by the control vanes are numerically determined for the sailcraft at any position with any pitch angle, which will be used as the restriction of the attitude control torques. The finite/infinite time adaptive sliding mode saturation controller and Bang–Bang–Radial Basis Function (RBF) controller are designed for the sailcraft with restricted attitude control torques. The model uncertainty and the input error (the error between real input and ideal control law input) are solved using the RBF network.

The finite true anomaly adaptive sliding mode saturation controller performed better than the other two controllers by comparing the numerical results in the paper. The control torque saturation, the model uncertainty and the external disturbance were also effectively solved using the infinite and finite time adaptive sliding mode saturation controllers by analyzing the numerical simulations. The stabilization of the pitch motion was accomplished within half orbit period.

The complex accurate dynamics can be approximated using the RBF network. The controllers can be applied to stabilization of spacecraft attitude dynamics with uncertainties in complex space environment.

Advanced control method is used in this paper; saturation of controlled torque of vane is resolved when the orbit with big eccentricity ration is considered and uncertainty and external disturbance under complex space background are settled. Moreover, complex and accurate nonlinear dynamical model of pitching axis of solar sail in body coordinate system compared with inertial coordinate system is provided.

During April-July 2013 the sailing cargo vessel Okeanos conducted a transport research project in Fiji. The vessel sailed regularly between Gau, Suva and Kadavu where transport data were collected. The purpose of this paper is to investigate the transport need in the islands and how a smaller, cheap sailing vessel would perform and meet that need and if it can be economically sustainable.

Maritime Safety Authority of Fiji and the Ministry of Public Utilities, Transport and Works, issued a temporary safety certificate and verbally agreed on Okeanos working in a non-commercial capacity for four months. The preparations allowed for 31 days continuous traffic in Kadavu and Lomaiviti area.

–Okeanos carried 22 tons cargo and 55 passengers during 31 days. The trial shows that sailing time affects the running costs and make route planning essential for a sailing vessel. The results indicate that a sailing operation can be economically sustainable for routes that allow at least two return sails a week. To expand the operation to tourist-passengers willing to pay higher fees would be a more sustainable alternative. Simulations in the appendix with fictive values for transporting goods and passengers illustrate the feasibility of various options.

Limited permits and licenses allowed only for a short trial. Permits also prohibited the trial to engage in full commercial capacity.

The study provides a transport trial with measurable outcomes. It can justify further and more extensive trials with alternative transport methods to remote islands and villages.

Several spacecraft beam‐propulsion concepts are introduced. “Mesoparticle beam propulsion” uses a collimated beam of mesoscopic particles, very roughly on the order of a nanogram mass each. Molecular nanotechnologies may permit the inclusion of entire guidance systems in each particle. “Micro Lightsails for beam propulsion” proposes matter‐beams composed of small, thin film lightsails with nanoscale components. Pushing a spacecraft with small, high velocity lightsails may be currently viable. “Ultracold matter beam generators” are proposed as a new type of space‐based particle‐beam. Design‐variants include a laser‐cooled thermal jet and a laser‐cooled, neutralized‐ion beam. Possible uses include the shipment of condensed, ultracold matter through space, the formation of an “artificial aerobraking corridor”, and beam‐propulsion for micro and nanospacecraft.

The purpose of this paper is to describe the first and novel beam splitting day-lighting system possessing highest possible solar transmission efficiency to provide illumination to the core and underground areas of any structure/building.

In this system, by using a number of individually pointable thin and light optical elements mounted on a top of structure/building, the solar light is concentrated. The concentrated beam is focussed to a secondary reflecting element which directs it to a beam splitter while passing through a Fresnel lens and a horizontal solar pipe. The beam splitter located inside the structure/building splits the solar beam into a number of secondary beams using a special arrangement of a number of inbuilt light guiding optical elements inside the beam splitter. The beam splitter produces a desired number of beams which are then redirected to the beam diffusers with the help of the solar pipe and the solar pipe joint which deflects the light at the angle of 90°.

The system considers the use of highly sophisticated and the highly efficient optical elements so that to attain the highest possible end-to-end efficiency of the system. The system has the highest potential to transport the solar energy to larger distances than all the available day-lighting systems and possesses the potential to be used for underground human colonisation.

The widespread adoption of such a system could substantially reduce energy consumption worldwide, which would contribute to bring down the increasing slope in the graph of greenhouse gases.

The paper presents the novel beam splitting day-lighting system.

This paper aims to suggest a new thermonuclear space propulsion and electric generator for aerospace.

Methods of thermonuclear physics are used for research.

The paper applies, develops and researches mini‐sized Micro‐AB thermonuclear reactors for space propulsion and space power systems. These small engines directly convert the high‐speed charged particles produced in the thermonuclear reactor into vehicle thrust or vehicle electricity with maximum efficiency. The simplest AB‐thermonuclear propulsion offered allows spaceships to reach speeds of 20,000‐50,000 km/s (1/6 of light speed) for fuel ratio 0.1 and produces a huge amount of useful electric energy. The offered propulsion system permits flight to any planet of the solar system in a short time and to the nearest non‐Sun stars by E‐being or intellectual robots during a single human life period.

Technical limitations may be apparent.

The theory of this propulsion and electric generator is developed and possibilities researched.

A range of space systems engineering technologies are currently under development at the University of Glasgow. Much of this work centres on advanced propulsion (solar sailing and tethers) which is complemented by studies on space robotics and spacecraft autonomy. This paper summarises these activities to provide a brief overview of current research interests. Although some work represents fundamental research in space systems engineering, much is mission‐oriented and focused on future exploitation.

The purpose of this paper is to propose a pre-defined performance robust control method for pre-assembly configuration establishment of in-space assembly missions, and collision avoidance is considered during the configuration establishment process.

First, six-degrees-of-freedom error kinematic and dynamic models of relative translational and rotational motion between transportation systems are developed. Second, the prescribed transient-state performance bounds of tracking errors are designed. In addition, based on the backstepping, combining the pre-defined performance control method with a robust control method, a pre-defined performance robust controller is designed.

By designing prescribed transient-state performance bounds of tracking errors to guarantee that there is no overshoot, collision-avoidance can be achieved. Combining the pre-defined performance control method with a robust control method, robustness to disturbance is guaranteed.

This paper proposed a pre-defined performance robust control method. Simulation results demonstrate that the proposed controller can achieve a pre-assembly configuration establishment with collision avoidance in the existence of external disturbances.

“Microscale light sails” (MLS) are simultaneously manufactured and launched as a matter‐beam from a proposed Lunar facility. Lunar aluminum would be refined for the feedstock of this “thin film beam generator”. A battery of linear, aluminum‐vapor, rocket engines make up the first stage of a “laser cooled thermal beam”. After a supersonic expansion, the condensing sheets of AlI atoms undergo light‐force mediated cooling, guidance, and compression. The individual, partly condensed sheets are brought together at sufficiently low energy to form the core of the thin film. MLS‐swarms can become either the reaction‐mass for a deep space, beam‐propulsion transportation network, the constituents of an orbital space‐mirror or an interstellar, laser‐driven probe, or simply be used as raw building material for outer space structures. An articulation of the beam generator may manufacture solar cells and other kinds of thin‐films from space resources.