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This paper aims to propose a united kinematic calibration method for a dual-machine system in automatic drilling and riveting. The method takes both absolute and relative pose accuracy into account, which will largely influence the machining accuracy of the dual-machine system and assembly quality.

A comprehensive kinematic model of the dual-machine system is established by the superposition of sub-models with pose constraints, which involves base frame parameters, kinematic parameters and tool frame parameters. Based on the kinematic model and the actual pose error data measured by a laser tracker, the parameters of coordinated machines are identified by the Levenberg–Marquardt method as a multi-objective nonlinear optimization problem. The identified parameters of the coordinated machines will be used in the control system.

A new calibration method for the dual-machine system is developed, including a comprehensive kinematic model and an efficient parameter identification method. The experiment results show that with the proposed method, the pose accuracy of the dual-machine system was remarkably improved, especially the relative position and orientation errors.

This method has been used in an aircraft assembly project. The calibrated dual-machine system shows a good performance on system coordination and machining accuracy.

This paper proposes a new method with high accuracy and efficiency for the dual-machine system calibration. The research can be extended to multi-machine and multi-robot fields to improve the system precision.

The purpose of this paper is to design, analyze and optimize a new type of inner-side working head for automatic horizontal dual-machine cooperative drilling and riveting system. The inner-side working head is the key component of automatic drilling and riveting system, and it is a challenge to design an inner-side working head which must be stiffness and stable with a compact structure to realize its functions.

According to the assembly structure features of large aircraft panels and riveting process requirements, a new type of inner-side working head is designed for pressure riveting. The force condition of the inner-side working head during the riveting process is analyzed and the deformation model is established. Design optimization is performed based on genetic algorithm and finite element analysis. The optimized inner-side working head is tested with automatic horizontal dual-machine cooperative drilling and riveting system.

The deformation model provides the precision compensation basis for control system. Application test results show that the automatic drilling and riveting system can realize assembly of large aircraft panel with high efficiency and quality through the inner-side working head.

The inner-side working head has been used in aircraft panel assembly.

The inner-side working head has been used in aircraft panel assembly.

This paper presents the design, analysis and optimization of a new type of inner-side working head which can realize automatic riveting for aircraft panel. The research will promote the automation of aircraft panel assembly.

In manufacturing, dedicated machine tools and flexible machine tools are failing to satisfy the ever-changing manufacturing demands of short life cycles and dynamic nature of products. These machines are limited when new product designs are introduced. The solution lies in developing responsive machines that can be adjusted or be changed functionally when these change requirements arise. These machines are reconfigurable machines which are becoming the new focus, as they rapidly respond to product variety and volume changes. A sheet metal working machine known as a reconfigurable guillotine shear and bending press machine (RGS&BPM) has been developed. The purpose of this paper is to present a methodology, function-oriented design approach (FODA), which was developed for the design of the RGS&BPM.

The design of the machine is based on the six principles of reconfigurable manufacturing systems (RMSs), namely, modularity, scalability integrability, convertibility, diagnosability and customisability. The methodology seeks to optimise the design process of the RGS&BPM through a design of modules that make up the machine, enable its conversion and reconfiguration. The FODA is focussed on function identification to select the operational function required. Two main functions are recognised for the machine, these being cutting and bending; hence, the design revolves around these two and reconfigurability.

The developed design methodology was tested in the design of a prototype for the reconfigurable guillotine shear and bending press machine. The prototype is currently being manufactured and will be subjected to functional tests once completed. This paper is being presented not only to present the methodology by to show and highlight its practical applicability, as the prototype manufacturers have been enthusiastic about this new approach.

The research was limited to the design methodology for the RGS&BPM, the machine which has been designed to completion using this methodology, with prototype being manufactured.

This study presents critical steps and considerations in the development of reconfigurable machines. The main thrust being to explore the best possibility of developing the machines with dual functionality that will assist in availing the technology to manufacturer. As the machine has been development, the success of the design can be directly attributed to the FODA methodology, among other contributing factors. It also highlights the significance of the principles of RMS in reconfigurable machine design.

The RGS&BM machine is an answer for the small-to-medium enterprises (SMEs), as the machine replaces two machines with one, and the methodology ensures its affordable design. It contributes immensely to the machine availability by eliminating trial and error approaches.

This study presents a new approach to the design of reconfigurable dual machines using principles of RMS. As the targeted market is the SME, it is not limited to that as any entrepreneur may use the machine to their advantage. The design methodology presented contributes to the body of knowledge in dual reconfigurable machine tool design.

Many people feel the automated guided vehicle business is about to take off in the way that robotics did some years ago. John Mortimer reports

ON show for the first time at MACH 88 from the Industrial Automation Division of Robert Bosch Ltd., is their flexible Direct Numerical Control (DNC) system for machine tools.

Argues that the amount and complexity of paperwork is increasing, yet investment in replacing manual record‐keeping systems is often a low priority. Highlights the experience of Presswork (Metals) Ltd, which has invested in IT as part of an integrated TQM strategy. Quotes senior managers and charts the progress of the company′s TQM approach, including employee involvement, training and customer/supplier relationships. Concludes that what the company is doing is nothing new, but simply adopting to best advantage the benefits of IT.

The purpose of this paper extends the authors’ previous contributions on aircraft system identification, such as open loop identification or closed loop identification, to cascade system identification. Because the cascade system is one special network system, existing in lots of practical engineers, more unknown systems are needed to identify simultaneously within the statistical environment with the probabilistic noises. Consider this problem of cascade system identification, prediction error method is proposed to identify three unknown systems, which are parameterized by three unknown parameter vectors. Then the cascade system identification is transferred as one parameter identification problem, being solved by the online subgradient descent algorithm. Furthermore, the nonparametric estimation is proposed to consider the general case without any parameterized process. To make up the identification mission, model validation process is given to show the asymptotic interval of the identified parameter. Finally, simulation example confirms the proposed theoretical results.

Firstly, aircraft system identification is reviewed through the understanding about system identification and advances in control theory, then cascade system identification is introduced to be one special network system. Secondly, for the problem of cascade system identification, prediction error method and online subgradient decent algorithm are combined together to identify the cascade system with the parameterized systems. Thirdly from the point of more general completeness, another way is proposed to identify the nonparametric estimation, then model validation process is added to complete the whole identification mission.

This cascade system corresponds to one network system, existing in lots of practice, such as aircraft, ship and robot, so it is necessary to identify this cascade system, paving a way for latter network system identification. Parametric and nonparametric estimations are all studied within the statistical environment. Then research on bounded noise is an ongoing work.

To the best of the authors’ knowledge, research on aircraft system identification only concern on open loop and closed loop system identification, no any identification results about network system identification. This paper considers cascade system identification, being one special case on network system identification, so this paper paves a basic way for latter more advanced system identification and control theory.

We recall Sidney Greenstreet's profile of Humphrey Bogart in The Maltese Falcon: ‘Upon my soul sir, you are a character, you really are.’ The same might be said of Gorby, the leader of the second most powerful country in the world, whose stated philosophy over seventy years has been: profit is a moral evil.

The purpose of this paper is to use the redundancy of a new hybrid automatic fastening system (HAFS) for aircraft assembly in the best way.

First, the kinematic model of HAFS is divided into three sub-models, which are the upper/lower tool and parallel robot. With the geometric coordination relationship, a comprehensive kinematic model of the HAFS is built by mathematically assembling the sub-models based on the DH method. Then, a novel master-slave decoupling strategy for inverse kinematics solution is proposed. With the combination of the minimum energy consumption and the comfortable configuration, a multi-objective redundancy resolution method is developed to optimize the fastening configuration of the HAFS, which keep the HAFS away from the joint-limits and collision avoiding in the aircraft panel assembly process.

An efficient multi-objective posture optimization algorithm to use the redundancy in the best way is obtained. Simulation and an experiment are used to demonstrate the correctness of the proposed method. Moreover, the position and orientation errors of the drilling holes are within 0.222 mm and 0.356°, which are accurate enough for the automatic fastening in aircraft manufacturing.

This method has been used in the HAFS control system, and the practical results show the aircraft components can be fastened automatically through this method with high efficiency and high quality.

This paper proposes a comprehensive kinematic model and a novel decoupling strategy for inverse kinematic solution of the HAFS, which provides a reference to utilize the redundancy in the best way for a hybrid machine with redundant function.

The long controversy that has waxed furiously around the implementation of the EEC Directives on the inspection of poultry meat and hygiene standards to be observed in poultry slaughterhouses, cutting‐up premises, &c, appears to be resolved at last. (The Prayer lodged against the Regulations when they were formally laid before Parliament just before the summer recess, which meant they would have to be debated when the House reassembled, could have resulted in some delay to the early operative dates, but little chance of the main proposals being changed.) The controversy began as soon as the EEC draft directive was published and has continued from the Directive of 1971 with 1975 amendments. There has been long and painstaking study of problems by the Ministry with all interested parties; enforcement was not the least of these. The expansion and growth of the poultry meat industry in the past decade has been tremendous and the constitution of what is virtually a new service, within the framework of general food inspection, was inevitable. None will question the need for efficient inspection or improved and higher standards of hygiene, but the extent of the