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Article
Publication date: 21 February 2019

Liang Zhang, Changzhu Wei, Yin Diao and Naigang Cui

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

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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

Originality/value

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.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 4
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 1 October 2003

B. Paul Gibson

Light, when constructed in terms of the elementary quanta of light, may be viewed in particle‐like or wave‐like terms. The elementary quanta of light, when placed in…

Abstract

Light, when constructed in terms of the elementary quanta of light, may be viewed in particle‐like or wave‐like terms. The elementary quanta of light, when placed in motion through space/time at a speed of a constancy of c forms a light path through the space or reference frame viewed. The light path formed is curved, as space/time is curved. The curvilinear light path formed is a function of the gravitational potential within the viewed frame of reference. The linear description of this light path, termed the geodesic (Riemannian), does not describe the curvilinear light path, but rather the chord of the curvilinear path described by the inscribed arc. This linear description of the light path is the manner in which we describe the coordinate system involved, and is the same manner in which we determine the “speed of light”. The arc length of the light path, compared to the lesser value as described by the chord length, allows for a displacement to be determined, if both measures are applied to a linear measure. A displacement of linear coordinates then occurs, with this displacement a result of the gravitational potential occurring within the frame viewed. This displacement, derived via observation and predictions of the quantum model, resolves Maxwell as well as Newton. The theory concludes that the Special Theory of Relativity, suitably modified to account for gravitational displacement within one particular frame, derives a precise relative model of gravitation within the special frame. This model satisfies Newton, as the model arrives at an exact description of the three‐body problem.

Details

Kybernetes, vol. 32 no. 7/8
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 23 January 2009

Mahamadd Marrdonny and Mohammad Mobed

The purpose of this paper is to propose a new guidance algorithm for launching a satellite using an expendable rocket from an equatorial site to an equatorial low‐Earth orbit.

Abstract

Purpose

The purpose of this paper is to propose a new guidance algorithm for launching a satellite using an expendable rocket from an equatorial site to an equatorial low‐Earth orbit.

Design/methodology/approach

Guidance during endoatmospheric portion is based on a nominal trajectory computed prior to take‐off. A set of updating computations begins anew at the time instant tg of transition from endoatmosphere to exoatmosphere. The updating computations determine a guidance trajectory and an associated control law for the remainder of path by taking into account the rocket state at time tg. Thus, the overall guidance involves both initial and midcourse operations, and it has both open‐ and closed‐loop aspects.

Findings

Viability and performance in terms of speed, precision, and effectiveness of the proposed scheme is demonstrated through three‐dimensional simulations and comparisons to other methods.

Originality/value

The updating computations and the fashion in which they are incorporated into the entire guidance process constitute the novel features of the proposed algorithm.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 1 April 2000

Technology Task Group 3

Addresses the current state of the art of wireless technologies and infrastructures, projects where the field will be in the next decade, and discusses some of the…

Abstract

Addresses the current state of the art of wireless technologies and infrastructures, projects where the field will be in the next decade, and discusses some of the challenges that must be met. Elaborates on the established major areas of commercial wireless access technology in the USA, ranked by deployment extent, which are: terrestrial mobile wireless access; terrestrial broadband wireless access; and mobile satellite service.

Details

info, vol. 2 no. 2
Type: Research Article
ISSN: 1463-6697

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Article
Publication date: 23 January 2019

Huang Jianbin, Li Zhi, Huang Longfei, Meng Bo, Han Xu and Pang Yujia

According to the requirements of servicing and deorbiting the failure satellites, especially the tumbling ones on geosynchronous orbit, this paper aims to design a docking…

Abstract

Purpose

According to the requirements of servicing and deorbiting the failure satellites, especially the tumbling ones on geosynchronous orbit, this paper aims to design a docking mechanism to capture these tumbling satellites in orbit, to analyze the dynamics of the docking system and to develop a new collision force-limited control method in various docking speeds.

Design/methodology/approach

The mechanism includes a cone-rod mechanism which captures the apogee engine with a full consideration of despinning and damping characteristics and a locking and releasing mechanism which rigidly connects the international standard interface ring (Marman rings, such as 937B, 1194 and 1194A mechanical interface). The docking mechanism was designed under-actuated, aimed to greatly reduce the difficulty of control and ensure the continuity, synchronization and force uniformity under the process of repeatedly capturing, despinning, locking and releasing the tumbling satellite. The dynamic model of docking mechanism was established, and the impact force was analyzed in the docking process. Furthermore, a collision detection and compliance control method is proposed by using the active force-limited Cartesian impedance control and passive damping mechanism design.

Findings

A variety of conditions were set for the docking kinematics and dynamics simulation. The simulation and low-speed docking experiment results showed that the force translation in the docking phase was stable, the mechanism design scheme was reasonable and feasible and the proposed force-limited Cartesian impedance control could detect the collision and keep the external force within the desired value.

Originality/value

The paper presents a universal docking mechanism and force-limited Cartesian impedance control approach to capture the tumbling non-cooperative satellite. The docking mechanism was designed under-actuated to greatly reduce the difficulty of control and ensure the continuity, synchronization and force uniformity. The dynamic model of docking mechanism was established. The impact force was controlled within desired value by using a combination of active force-limited control approach and passive damping mechanism.

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Article
Publication date: 1 April 1989

JCSAT 1, Japan's first privately‐owned commercial communications satellite, launched by Ariane 4 rocket from French Guiana on 6th March, has now been manoeuvred into…

Abstract

JCSAT 1, Japan's first privately‐owned commercial communications satellite, launched by Ariane 4 rocket from French Guiana on 6th March, has now been manoeuvred into geosynchronous orbit over Longitude 150°E, with its antenna and solar arrays fully deployed.

Details

Aircraft Engineering and Aerospace Technology, vol. 61 no. 4
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 April 1981

GEORGE MERRICK

Two decades ago, the space age dawned, and we were awakened to a realm of technological possibilities beyond any we had imagined. Since that time, we have linked…

Abstract

Two decades ago, the space age dawned, and we were awakened to a realm of technological possibilities beyond any we had imagined. Since that time, we have linked continents with communication satellites, sent probes to other planets, and seen men on the moon. And, although we have made achievements that were almost inconceivable 30 years ago, we are still far from realising our potential for a future in space.

Details

Aircraft Engineering and Aerospace Technology, vol. 53 no. 4
Type: Research Article
ISSN: 0002-2667

Content available
Article
Publication date: 1 June 2021

Albert Vasso, Richard Cobb, John Colombi, Bryan Little and David Meyer

The US Government is challenged to maintain pace as the world’s de facto provider of space object cataloging data. Augmenting capabilities with nontraditional sensors…

Abstract

Purpose

The US Government is challenged to maintain pace as the world’s de facto provider of space object cataloging data. Augmenting capabilities with nontraditional sensors present an expeditious and low-cost improvement. However, the large tradespace and unexplored system of systems performance requirements pose a challenge to successful capitalization. This paper aims to better define and assess the utility of augmentation via a multi-disiplinary study.

Design/methodology/approach

Hypothetical telescope architectures are modeled and simulated on two separate days, then evaluated against performance measures and constraints using multi-objective optimization in a heuristic algorithm. Decision analysis and Pareto optimality identifies a set of high-performing architectures while preserving decision-maker design flexibility.

Findings

Capacity, coverage and maximum time unobserved are recommended as key performance measures. A total of 187 out of 1017 architectures were identified as top performers. A total of 29% of the sensors considered are found in over 80% of the top architectures. Additional considerations further reduce the tradespace to 19 best choices which collect an average of 49–51 observations per space object with a 595–630 min average maximum time unobserved, providing redundant coverage of the Geosynchronous Orbit belt. This represents a three-fold increase in capacity and coverage and a 2 h (16%) decrease in the maximum time unobserved compared to the baseline government-only architecture as-modeled.

Originality/value

This study validates the utility of an augmented network concept using a physics-based model and modern analytical techniques. It objectively responds to policy mandating cataloging improvements without relying solely on expert-derived point solutions.

Details

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

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Article
Publication date: 1 March 1994

Two high‐powered satellites built by Hughes Space and Communications Company (HSC) will bring true direct broadcast satellite (DBS) service to homes throughout North…

Abstract

Two high‐powered satellites built by Hughes Space and Communications Company (HSC) will bring true direct broadcast satellite (DBS) service to homes throughout North America starting in early 1994.

Details

Aircraft Engineering and Aerospace Technology, vol. 66 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 October 2003

B. Paul Gibson

Let us consider that light, when viewed as a particle, forms a conic arc segment inscribed within the space viewed. The space (or frame) viewed is considered to exhibit a…

Abstract

Let us consider that light, when viewed as a particle, forms a conic arc segment inscribed within the space viewed. The space (or frame) viewed is considered to exhibit a gravitational potential, and it is thus this potential that deforms the light path from a Euclidean/Newtonian derivation of a straight line to that of a relativistic curvilinear nature. Given a distance over this conic arc segment (assumed to form a parabolic arc segment) and a given time (considering the given distance involved), one derives a constancy of the speed of light of c, where c is considered as a constant regardless of the gravitational potential exhibited by the frame viewed. If we further consider that the Special Theory requires that light propagate on a linear measure as the velocity v (of necessity v being less than c on a comparable linear measure) between the axes concerned; then a displacement (in linear measure equal to c−v) occurs. The displacement evolved is then assumed to agree with the form of Maxwell. We assume that this linear displacement of c−v occurs upon the y‐axis of the frame viewed. Of necessity, a relative displacement must occur upon the x‐axis of the frame viewed. From the calculus, the dot products derived must vary in concept, in order to derive the totality of relative coordinate shifts occurring within any three‐dimensional space. One displacement is linear in nature, while the other is trigonometric in nature. We consider the displacement of Maxwell, Lorentz, Compton, and de Broglie to be linear in nature. Based on the principle of the Special Theory (and the other forms as mentioned), we consider the total displacement to be mechanically derivable. That derivation, once allowed, results the physics to agree with the observations complete to this moment in time. The paper concludes that the error in coordinate positioning shown by the global positioning satellite system (GPS satellite platform) is resolvable.

Details

Kybernetes, vol. 32 no. 7/8
Type: Research Article
ISSN: 0368-492X

Keywords

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