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Article
Publication date: 16 March 2012

Yawei Wang, Weihu Zhou, Xiaoquan Han, Zhongyu Wang and Jinbin Ding

The purpose of this paper is to describe a strap‐down image stable strategy for multi‐load optoelectronic imaging platform hung below a tethered aerostat.

Abstract

Purpose

The purpose of this paper is to describe a strap‐down image stable strategy for multi‐load optoelectronic imaging platform hung below a tethered aerostat.

Design/methodology/approach

Four two dimension pods, each with a visible light camera, are fixed on the optoelectronic platform. A POS (Position and Orientation System) is used to acquire the attitude rate data of optoelectronic platform, while the data can be coupled to the pods' servo systems through corresponding coordinate rotation, then the motors of pods will adjust the line of sight to the opposite way to keep the stabilization of image exported by visible light camcorders. Simultaneously, two rate gyros are installed at the inner frame of each pod, which are used as a backup to avoid the failure of POS.

Findings

Using one attitude and position measurement system can realize the stabilization of multi optoelectronic pods, which is same as or even better than the ratio gyro stabilization.

Research limitations/implications

As the tethered aerostat is a flexible body, it is affected a lot by the wind speed and wind direction at the low height (<1,000 m), which leads to the motors of pods always adjust the line of sight to the mechanical limiting of pods.

Practical implications

Strap‐down stabilization technology has been successfully used in the tethered aerostat monitoring platform to surveillance Shanghai World EXPO site. Long time experiments verify the feasible and effective of the multi‐load stabilization technology. The impact on the image by the adjustment of servos is less than 10 percent of the whole view of sight.

Originality/value

The paper introduces a strap‐down stabilization technology for multi‐load tethered aerostat platform, which is more suitable to be applied in the platform of relatively minor attitude change, like the airborne multi‐load platform and multi‐load UAV (unmanned aerial vehicle) platform.

Details

Aircraft Engineering and Aerospace Technology, vol. 84 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 9 November 2018

Komlan Kolegain, François Leonard, Sandra Chevret, Amarilys Ben Attar and Gabriel Abba

Robotic friction stir welding (RFSW) is an innovative process which enables solid-state welding of aluminum parts using robots. A major drawback of this process is that the robot…

225

Abstract

Purpose

Robotic friction stir welding (RFSW) is an innovative process which enables solid-state welding of aluminum parts using robots. A major drawback of this process is that the robot joints undergo elastic deformation during the welding, because of the high forces induced by the process. This leads to tool deviation and incorrect orientation. There is currently no computer-aided manufacturing/computer-aided design (CAD) software for generating off-line paths which integrates robot deflections, and the main purpose of this study is to propose an off-line methodology to plan a path for RFSW with the integration of the deflections.

Design/methodology/approach

The approach is divided into two steps. The first step consists of extracting position and orientation data from CAD models of the workpieces and adding the deflections calculated with a deflection model to generate a suitable path for performing RFSW. The second step consists of the smooth fitting of the suitable path using Bézier curves.

Findings

The method is experimentally validated by welding a curved workpiece using a Kuka KR500-2MT robot. A suitable tool position and orientation were calculated to perform this welding, an experimental procedure was set up, a defect-free weld was performed and a high accuracy was achieved in terms of position and orientation.

Practical implications

This method can help manufacturers to easily perform RFSW for three-dimensional workpieces regardless of the lateral tool deviation, loss of the right orientation and control force stability.

Originality/value

The originality of this method lies in compensating for robot deflections without using expensive sensors, which is the most commonly used method for compensating for robot deflection. This off-line method can lead to a reduction in programming time in comparison with teach programming method and leads to reduced investment costs in comparison with commercial off-line programming packages.

Details

Industrial Robot: An International Journal, vol. 45 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 15 August 2016

Behzad Bayat, Julita Bermejo-Alonso, Joel Carbonera, Tullio Facchinetti, Sandro Fiorini, Paulo Goncalves, Vitor A.M. Jorge, Maki Habib, Alaa Khamis, Kamilo Melo, Bao Nguyen, Joanna Isabelle Olszewska, Liam Paull, Edson Prestes, Veera Ragavan, Sajad Saeedi, Ricardo Sanz, Mae Seto, Bruce Spencer, Amirkhosro Vosughi and Howard Li

IEEE Ontologies for Robotics and Automation Working Group were divided into subgroups that were in charge of studying industrial robotics, service robotics and autonomous…

Abstract

Purpose

IEEE Ontologies for Robotics and Automation Working Group were divided into subgroups that were in charge of studying industrial robotics, service robotics and autonomous robotics. This paper aims to present the work in-progress developed by the autonomous robotics (AuR) subgroup. This group aims to extend the core ontology for robotics and automation to represent more specific concepts and axioms that are commonly used in autonomous robots.

Design/methodology/approach

For autonomous robots, various concepts for aerial robots, underwater robots and ground robots are described. Components of an autonomous system are defined, such as robotic platforms, actuators, sensors, control, state estimation, path planning, perception and decision-making.

Findings

AuR has identified the core concepts and domains needed to create an ontology for autonomous robots.

Practical implications

AuR targets to create a standard ontology to represent the knowledge and reasoning needed to create autonomous systems that comprise robots that can operate in the air, ground and underwater environments. The concepts in the developed ontology will endow a robot with autonomy, that is, endow robots with the ability to perform desired tasks in unstructured environments without continuous explicit human guidance.

Originality/value

Creating a standard for knowledge representation and reasoning in autonomous robotics will have a significant impact on all R&A domains, such as on the knowledge transmission among agents, including autonomous robots and humans. This tends to facilitate the communication among them and also provide reasoning capabilities involving the knowledge of all elements using the ontology. This will result in improved autonomy of autonomous systems. The autonomy will have considerable impact on how robots interact with humans. As a result, the use of robots will further benefit our society. Many tedious tasks that currently can only be performed by humans will be performed by robots, which will further improve the quality of life. To the best of the authors’knowledge, AuR is the first group that adopts a systematic approach to develop ontologies consisting of specific concepts and axioms that are commonly used in autonomous robots.

Details

Industrial Robot: An International Journal, vol. 43 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 11 June 2019

Shijia Wang

This paper aims to improve shearer positioning accuracy. Shearer positioning using an inertial navigation system (INS) is a highly useful technology; however, positioning accuracy…

Abstract

Purpose

This paper aims to improve shearer positioning accuracy. Shearer positioning using an inertial navigation system (INS) is a highly useful technology; however, positioning accuracy is seriously hindered by INS attitude error, particularly heading drift.

Design/methodology/approach

A shearer positioning model with double-INS based on extended Kalman filter was proposed. The constant distance between two INSs (INS 1 and INS 2) was selected as the observation vector. Allan variance was used to identify the noise type of the vertical-axis gyroscope, and the stochastic process of heading drift for two INSs was obtained and divided into incongruous drift and concurrent drift.

Findings

Simulation was then carried out to determine the optimal arrangement of the two INSs. For incongruous drift, the optimal arrangement satisfied the condition that the line connecting INS 1 and INS 2 was perpendicular to the shearer lateral axis (in the shearer coordinate frame) and parallel to the east-north plane (in the east-north-up coordinate frame). Under optimal arrangement, the positioning accuracy increased against the distance between INS 1 and INS 2. For concurrent drift, the double-INS positioning model had no effect. Under the circumstances, the number of INSs should be increased so that the uncertainty of INS drift was reflected as much as possible.

Originality/value

A new double-INS positioning model was proposed with the constant distance between the two INSs. The optimal arrangement for double-INS was obtained.

Details

Sensor Review, vol. 39 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 5 March 2018

Haiying Liu, Xin Jiang, Yazhou Yue and Guangen Gao

The study aims to propose reverse processing solution to improve the performance of strapdown inertial navigation system (SINS) initial alignment and SINS-/global positioning…

263

Abstract

Purpose

The study aims to propose reverse processing solution to improve the performance of strapdown inertial navigation system (SINS) initial alignment and SINS-/global positioning system- (GPS) integrated navigation. The proposed scheme can be well applied in the fields of aircraft and aerospace navigation.

Design/methodology/approach

For the SINS alignment phase, a fast initial alignment scheme is proposed: the initial value of reverse filter is determined by the final result of forward filter, and then, the reverse filter is carried out using the stored data. Multiple iterations are performed until the accuracy is satisfied. For the SINS-/GPS-integrated phase, a forward–reverse navigation algorithm is proposed: first, the standard forward filter is used, and then, the reverse filter is carried out using the initial value determined by the forward filter, and the final fusion results are achieved by the weighted smoothing of the forward and reverse filtering results.

Findings

The simulation and the actual test results show that in the initial alignment stage, the proposed reverse processing method can obviously shorten the SINS alignment time and improve the alignment accuracy. In the SINS-/GPS-integrated navigation data fusion stage, the proposed forward–reverse data fusion processing can, obviously, improve the performance of the navigation solution.

Practical implications

The proposed reverse processing technology has an important application in improving the accuracy of navigation and evaluating the performance of real-time navigation. The proposed scheme can be not only used for SINS-/GPS-integrated system but also applied to other integrated systems for general aviation aircraft.

Originality/value

Compared with the common forward filtering algorithm, the proposed reverse scheme can not only shorten alignment time and improve alignment accuracy but also improve the performance of the integrated navigation.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 April 1970

Klaus Peters

THE German aerospace industry faces the new decade with optimism. Even the budget restrictions announced recently which affect most parts of the industry cannot lessen that…

Abstract

THE German aerospace industry faces the new decade with optimism. Even the budget restrictions announced recently which affect most parts of the industry cannot lessen that impression. Some of the money not granted has only been frozen to avoid further overheating of the economy. In comparison with the aerospace industries of Great Britain — employing 240,000 people — and France — employing 100,000 people — the German aerospace industry with its 52,000 employees seems to be of less importance. This figure, however, is remarkable with regard to the fact that in 1956 this industry had to start from nothing. The airframe industry employs about 32,500, the space industry some 2,600, the engine industry about 6,200, the material and accessory industry 3,000 employees, and in the equipment industry another 7,200 people are working directly for the aerospace industry.

Details

Aircraft Engineering and Aerospace Technology, vol. 42 no. 4
Type: Research Article
ISSN: 0002-2667

Content available
Article
Publication date: 1 December 2005

Stephen Todd

94

Abstract

Details

Structural Survey, vol. 23 no. 5
Type: Research Article
ISSN: 0263-080X

Article
Publication date: 12 August 2014

Zhangjun Jin, Cijun Yu, Jiangxiong Li and Yinglin Ke

The purpose of this paper is to propose a robot-assisted assembly system (RAAS) for the installation of a variety of small components in the aircraft assembly system. The RAAS is…

Abstract

Purpose

The purpose of this paper is to propose a robot-assisted assembly system (RAAS) for the installation of a variety of small components in the aircraft assembly system. The RAAS is designed to improve the assembly accuracy and increase the productive efficiency.

Design/methodology/approach

The RAAS is a closed-loop feedback system, which is integrated with a laser tracking system and an industrial robot system. The laser tracking system is used to evaluate the deviations of the position and orientation of the small component and the industrial robot system is used to locate and re-align the small component according to the deviations.

Findings

The RAAS has exhibited considerable accuracy improvement and acceptable assembly efficiency in aircraft assembly project. With the RAAS, the maximum position deviation of the component is reduced to 0.069 mm and the maximum orientation deviation is reduced to 0.013°.

Social implications

The RAAS is applied successfully in one of the aircraft final assembly projects in southwest China.

Originality/value

By integrating the laser tracking system, the RAAS is constructed as a closed-loop feedback system of both the position and orientation of the component. With the RAAS, the installation a variety of small components can be dealt with by a single industrial robot.

Details

Industrial Robot: An International Journal, vol. 41 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 April 1989

Anghel N. Rugina

There is a double crisis in modern science and in particular inphysics and mechanics. Among others Einstein and Stephane Lupasco, inthe 1930s, warned about this crisis. The…

1985

Abstract

There is a double crisis in modern science and in particular in physics and mechanics. Among others Einstein and Stephane Lupasco, in the 1930s, warned about this crisis. The Quantum Theory cannot be reconciled with the Relativity Theory. Specifically there is a gap (cleavage) between micro – and macro‐physics and mechanics. Parallel or beneath there is also a second crisis derived from a discontinuity (again a cleavage) between classical and modern science, that is between two previous revolutions. A new research programme of a simultaneous equilibrium versus disequilibrium approach, initially applied in economics has now been extended to include natural sciences. It is the question of a new, more comprehensive methodology which is actually a sui generis synthesis between classical and modern heritage. The rigorous application of the new research programme leads to the organisation of an Orientation Table, that is, a methodological map of all possible combinations (systems). The Table shows, without any exaggeration, a few revolutionary results. For instance, with the help of the Table, modern science or the second revolution (Einstein, Bohr, Heisenberg) does not appear contradictory but rather complementary to classical science or the first revolution (Newton, Lavoisier). The Kuhnian thesis to the contrary is disproved and the second crisis is solved. With the help of the Universal Hypothesis of Duality (the basis of the Orientation Table), matter and energy, at the micro – and macro‐level, appear in a double form (the Principle of Duality): stable (equilibrium) particles and unstable (disequilibrium) waves. The strong interactions from modern physics are associated with the law of gravitation (attraction) or stable equilibrium which governs stable matter and energy. The weak interactions are associated with the law of disgravitation (dispersion or repulsion) including entropy or unstable equilibrium which governs unstable matter and energy. In this way the first crisis is also solved.

Details

International Journal of Social Economics, vol. 16 no. 4
Type: Research Article
ISSN: 0306-8293

Keywords

Article
Publication date: 1 May 2000

Anghel N. Rugina

Attempts to prove, in this second chapter of the author’s monograph, that with a new research programme, it is possible to build a methodological bridge between economics and all…

4020

Abstract

Attempts to prove, in this second chapter of the author’s monograph, that with a new research programme, it is possible to build a methodological bridge between economics and all other natural sciences and the scientists should address this challenge. Reviews basic principles that govern nature, including Einstein’s findings along with such luminaries as Copernicus, Newton, Galileo and Jeans. Concludes that the future is safe, as a new generation of scientists is now emerging in the East and the West, and that the new methodology should provide enough space for new roads, ideas and interpretations, which may occur in the future. Closes by saying a new spirit should be initiated in economics and transplanted into natural sciences.

Details

International Journal of Social Economics, vol. 27 no. 5/6
Type: Research Article
ISSN: 0306-8293

Keywords

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