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A large number of fastener holes have to be drilled with high quality in the circumferential splice region during the assembly of aircraft fuselage. The purpose of this paper is to design an automatic stepping mechanism for a circumferential splice drilling machine, to meet the requirements of large workspace and high accuracy in drilling at the same time.

A docking position detection method based on magnetic proximity sensors is proposed for the positioning of the arc-shaped rail with respect to the circumferential rails, which significantly improves the accuracy and reliability of automatic stepping. The slipping phenomenon of the end-effector is analyzed, and the optimized counter weights are used to eliminate the slipping and improve the working stability of the stepping mechanism.

An automatic stepping mechanism is developed for the circumferential splice drilling machine, which comprises the docking position detection method and the elimination/suppression method of the end-effector’s slipping.

The proposed automatic stepping mechanism has been integrated into the circumferential splice drilling machine for the fuselage assembly in an aircraft company in China.

An automatic stepping scheme for the circumferential splice drilling machine is proposed, which enhances the efficiency in circumferential splice drilling in aircraft fuselage assembly.

The analysis of power flow and mechanical efficiency constitutes an important phase in the design and analysis of gear mechanisms. The aim of this paper is to present a systematic procedure for the determination of power flow and mechanical efficiency of epicyclic-type transmission mechanisms.

A novel epicyclic-type in-hub bicycle transmission, which is a split-power type transmission composed of two transmission units and one differential unit, and its clutching sequence table are introduced first. By using the concept of fundamental circuits, the procedure for calculating the angular speed of each link, the ideal torque and power flow of each link, the actual torque and power flow of each link determined by considering gear-mesh losses, and the mechanical efficiency of the transmission mechanism is proposed in a simple, straightforward manner. The mechanical efficiency analysis of epicyclic-type gear mechanisms is largely simplified to overcome tedious and complicated processes of traditionally methods.

An analysis of the mechanical efficiency of a four-speed automotive automatic transmission completed by Hsu and Huang is used as an example to illustrate the utility and validity of the proposed procedure. The power flow and mechanical efficiency of the presented 16-speed in-hub bicycle transmission are computed, and the power recirculation inside the transmission mechanism at each speed is detected based on the power flow diagram. When power recirculation occurs, the mechanical efficiency of the gear mechanism at the related speed reduces. The mechanical efficiency of this in-hub bicycle transmission is more than 96 percent for each speed. Such an in-hub bicycle transmission possesses reasonable kinematics and high mechanical efficiency and is therefore suitable for further embodiment design and detail design.

The proposed approach is suitable for the mechanical efficiency analysis of all kinds of complicated epicyclic-type transmissions with any number of degrees of freedom and facilitates a less-tedious process of determining mechanical efficiency. It is a useful tool for mechanical engineering designers to evaluate the efficiency performance of the gear mechanism before actually fabricating a prototype as well as measuring the numerical data. It also helps engineering designers to cautiously select feasible gear mechanisms to avoid those configurations with power recirculation in the preliminary design stage which may significantly reduce the time for developing novel in-hub bicycle transmissions.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

The purpose of this study is to propose an automatic leveling method for a printing platform based on a three-point coordinate feedback. The proposed method is used in fused deposition modeling additive manufacturing systems. The coordinate error of the leveled plane is constrained to within  ± 0.2 mm, which is less than the printed layer thickness.

First, the model of the forward and inverse solutions of the parallel arm is obtained based on the principles of vector algebra. Second, the automatic leveling mechanism for collecting the z-coordinate is designed. The best position of the virtual origin plane is obtained by comparing the z-coordinates of the test points. Finally, after making multiple adjustments through a closed-loop z-coordinate feedback, the parallelism of the printing plane and the virtual origin plane is limited to an effective range.

The experimental results show that after three leveling attempts, the z-coordinate of the test points can be constrained to within  ± 0.2 mm, which shows that this method can effectively achieve automatic leveling in a delta three-dimensional (3D) printer.

This study presents a novel and distinctive delta 3D printer leveling system by designing a leveling mechanism and a leveling algorithm. The method uses a closed-loop feedback mode to make the leveling process simple, convenient and efficient without requiring major changes to the printer. The error after leveling is less than the printed layer thickness, which fully guarantees the accuracy of the leveling process.

The purpose of this paper is to describe the development of a robot for surveillance able to move in structured and unstructured environments and able to overcome obstacles with high energetic efficiency.

The proposed Epi.q‐TG hybrid robot combines wheeled and legged locomotion. It is equipped with four three‐wheeled locomotion units; traction is generated by the two forecarriage units, while the two rear ones have same geometry but are idle. Each front unit is actuated by a single motor with the interposition of an epicyclical gearing, accurately designed in order to suitably switch between wheeled and legged motion. The robot changes locomotion mode from rolling on wheels (advancing mode) to stepping on legs (automatic climbing mode) according to local friction and dynamic conditions.

The experimental results confirm the design objectives. In advancing mode, the robot behaves like a four‐wheeled vehicle, with high speed and energetic efficiency. In automatic climbing mode, the robot can walk on uneven and soft terrains and overcome steps with remarkable height with respect to its dimensions (up to 84 per cent of the locomotion unit height).

Besides surveillance, Epi.q‐TG can be successfully used in many tasks in which it is useful to combine the advantages of wheeled and legged locomotion, e.g. unmanned inspection of nuclear and chemical sites, minesweeping, and intervention in disaster zones.

The core of the project is the epicyclical mechanism of the locomotion unit, which switches between advancing mode and automatic climbing mode without control action. This solution limits the control and actuation complexity and consequently the robot cost, widening the range of possible applications.

This paper aims to examine the effectiveness of organizational information technology (IT)-based and non-IT-based knowledge transfer mechanisms (KTMs) for the retention of different types of knowledge from mobile experts. It differentiates among four types of knowledge loss (KL), namely, conscious knowledge (i.e. individual explicit knowledge that can be codified); codified knowledge (i.e. explicit knowledge captured at the social level); automatic knowledge (i.e. implicit individual knowledge); and collective knowledge (i.e. implicit knowledge embedded in the organization).

A research framework connecting the organizational knowledge retention (KR) cycle to KL is developed and an exploratory analysis is conducted using data from two case studies in the Canadian federal public service. Findings are confirmed using a third government agency.

Without the right processes in place for organizational knowledge retrieval and reuse, the KR cycle is not complete, leading to KL. The lack of available social KTMs for the conversion of individual to social objectified knowledge leads to KL. KTMs shortcomings increase the risk of automatic and objectified KL.

Exploratory results demonstrate that KL does not always equate to lack of KR. Implementing knowledge-specific organizational KTMs is important to encourage the retention of individual knowledge at the social level. Propositions and a framework are developed for future research.

Mobile experts hold valuable knowledge at high risk of being lost by organizations. This paper provides managers with a set of guidelines to develop a knowledge-specific strategy focused on KTMs that increase KR and mitigate KL.

This paper challenges the assumption that KL only results from poor retention and studies both retention and loss to identify additional types of unintentional loss that occur when individual knowledge is not converted to social knowledge.

This paper aims to present the development of an automated inspection system (AIS) using an image-based analysis mechanism, called i-AIS. The development process of i-AIS used the Design Six Sigma (DSS) methodology. The steps of define, measure, analyze, design and verify (DMADV) are applied and integrated with specific analyses techniques of the quality function deployment (QFD), design failure mode effect analysis (DFMEA) and theory of inventive problem solving (TRIZ). The production process of adhesive tape is the focused case study in this research project, motivated by the high product defect rate complained by customers.

The development process of i-AIS was divided into five standard steps based on the DSS methodologies of DMADV. One of the key processes in this development was to systematically identify the right and intended features of i-AIS. This was carried out based on the application of the QFD technique. Another important process was to further investigate the possible causes of i-AIS failure, to function as intended. This investigative process was carried out based on the DFMEA technique, while the solution to minimize the risk of the identified failures was obtained from the TRIZ method. The final prototype of i-AIS was then presented in the design step.

Verification of the i-AIS prototype revealed its operation at an optimally intended mode that fulfilled the requirements of internal customers. Verification results also revealed that the sigma level has improved from 3.87 to 4.33. Meanwhile, the defect reduction rate is improved to 74.4% and downtime rate also recorded a significant improvement at 80.7% of reduction.

The presented research work is carried out based on a customized case study. Although the proposed methodology can be applied to others cases towards design-based solution, some modifications maybe required based on to the unique features of the case study under consideration.

The presented research project indicated that the proposed methodology was successful to facilitate a structured and systematic process towards defect identification, classification, evaluation and generation of a solution.

The paper presents the development process of an AIS by considering comprehensive managerial aspects that are currently absent in the literature. An integrated DSS structure is proposed to systematically guide the development of i-AIS. The related managerial aspects such as identification of critical defects problem, customer requirement mapping, prototype design analysis and comparison measurements before and after i-AIS installation are considered in this research project.

Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way of using the law in specific circumstances, and shows the variations therein. Sums up that arbitration is much the better way to gok as it avoids delays and expenses, plus the vexation/frustration of normal litigation. Concludes that the US and Greek constitutions and common law tradition in England appear to allow involved parties to choose their own judge, who can thus be an arbitrator. Discusses e‐commerce and speculates on this for the future.

The object of this research is the reconstruction of the existing legal response by European Union states to the phenomenon of immigration. It seeks to analyse the process of conferral of protection.

One main dimension is selected and discussed: the case law of the national courts. The study focuses on the legal status of immigrants resulting from the intervention of these national courts.

The research shows that although the courts have conferred an increasing protection on immigrants, this has not challenged the fundamental principle of the sovereignty of the states to decide, according to their discretionary prerogatives, which immigrants are allowed to enter and stay in their territories. Notwithstanding the differences in the general constitutional and legal structures, the research also shows that the courts of the three countries considered – France, Germany and Spain – have progressively moved towards converging solutions in protecting immigrants.

The research contributes to a better understanding of the different legal orders analysed.