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Slim and dexterous manipulators with long reaches can perform various exploration and inspection tasks in confined spaces. This paper aims to present the development of such a dexterous continuum manipulator for potential applications in the aviation industry.

Benefiting from a newly conceived dual continuum mechanism and the improved actuation scheme, this paper proposes a design of a slim and dexterous continuum manipulator. Kinematics modeling, simulation-based dimension synthesis, structural constructions and system descriptions are elaborated.

Experimental validations show that the constructed prototype possesses the desired dexterity to navigate through confined spaces with its kinematics calibrated and actuation compensation implemented. The continuum manipulator with different deployed tools (e.g. graspers and welding guns) would be able to perform inspections and other tasks at remote locations in constrained environments.

The current construction of the continuum manipulator possesses quite some friction inside its structure. The bending discrepancy caused by friction could accumulate to an obvious level. It is desired to further reduce the friction, even though the actuation compensation had been implemented.

The constructed continuum manipulator could perform inspection and other tasks in confined spaces, acting as an active multi-functional endoscopic platform. Such a device could greatly facilitate routine tasks in the aviation industry, such as guided assembling, inspection and maintenance.

The originality and values of this paper mainly lay on the design, modeling, construction and experimental validations of the slim and dexterous continuum manipulator for the desired mobility and functionality in confined spaces.

Pick-and-place tasks are common across many industrial sectors, and many rigid-linked robots have been proposed for this application. This paper aims to alternatively present the development of a continuum robot for low-load medium-speed pick-and-place tasks.

An inversion of a previously proposed dual continuum mechanism, as a key design element, was used to realize the horizontal movements of the CurviPicker’s end effector. A flexible shaft was inserted to realize rotation and translation about a vertical axis. The design concept, kinematics, system descriptions and proof-of-concept experimental characterizations are elaborated.

Experimental characterizations show that the CurviPicker can achieve satisfactory accuracy after motion calibration. The CurviPicker is easy to control due to its simple kinematics, while its structural compliance makes it safe to work with, as well as less sensitive to possible target picking position errors to avoid damaging itself or the to-be-picked objects.

The vertical translation of the CurviPicker is currently realized by moving the flexible shaft. Insertion of the flexible shaft introduces possible disturbances. It is desired to explore other form of variations to use structural deformation to realize the vertical translation.

The proposed CurviPicker realizes the Schöenflies motions via a simple structure. Such a robot can be used to increase robot presence and automation in small businesses for low-load medium-speed pick-and-place tasks.

To the best of the authors’ knowledge, the CurviPicker is the first continuum robot designed and constructed for pick-and-place tasks. The originality stems from the concept, kinematics, development and proof-of-concept experimental characterizations of the CurviPicker.

To reduce the flammability exposure assessment time and meet the requirements of airworthiness regulations of transport aircraft, inerting system has become the standard configuration of modern civil aircraft. Therefore, airworthiness regulations put forward definite quantitative index requirements for the safety of inerting system, and to obtain the quantitative data of the safety of inerting system, it is necessary to solve the calculation method. As one of the quantitative/qualitative evaluation techniques for system safety, fault tree analysis is recognized by international airworthiness organizations and national airworthiness certification agencies. When fault tree analysis technology is applied to quantitative analysis of the safety of inerted system, there are still some problems, such as heavy margin of constructing fault tree, great difficulty, high requirement for analysts and poor accuracy of solving when there are too many minimum cut sets. However, based on tens of thousands of flight simulation tests, Monte Carlo random number generation method can solve this problem.

In this paper, the fault tree of airborne inerting system is established, and the top event is airborne inerting system losing air separation function. Monte Carlo method based on random number generation is used to carry out system security analysis. The reliability of this method is verified.

The static fault tree analysis method based on Monte Carlo random number generation can not only solve the problem of quantitative analysis of inerting system, but can also avoid the defects of complicated solution and inaccurate solution caused by the large number of minimum cut sets, and its calculation results have good reliability.

The research results of this paper can be used as supporting evidence for airworthiness compliance of airborne inerting system.

The research results of this paper can provide practical guidance for the current civil airworthiness certification work.

Carbon emission is one of the most important problems of today. In this framework, it is important for countries to take the necessary actions to solve this problem. Energy use is one of the most important causes of carbon emissions. Choosing fossil fuels in this process increases the carbon emission problem. Therefore, it is understood that countries should be more sensitive about energy types. In this context, renewable energy (RE) sources are recommended by experts. However, due to some problems of these energy types, it does not seem possible to meet all energy needs from these sources. It is thought that nuclear energy will produce a permanent solution to the carbon emission problem. In this context, it is recommended that the use of nuclear energy be put on the agenda by countries.

This study aims to obtain the speed and angle during safe and comfortable standing of elderly people. With the advancement of society, it is becoming increasingly difficult for the elderly to sit-to-stand (STS) independently and comfortably in a safe and comfortable manner. Safety is essentially a prerequisite for the elderly to achieve a comfortable STS. The speed, angle and power of the STS process can all affect safe STS. From the standpoint of health-care delivery and administration, comfortable STS can be realized easily by addressing the safety issues during STS.

This paper summarizes the research progress on speed and angle during safe and comfortable standing of older people. The authors analyzed the speed and angle of the STS using the Vicon optical gait acquisition system and plantar pressure sensor to find the appropriate angle and speed thresholds.

The center of gravity movement is a prerequisite for the elderly to achieve a comfortable STS. The authors found that the standing speed during the STS process should not be higher than 103.8 mm/s so that the elderly can stand comfortably and safely (safe and dangerous speeds are 72.8 mm/s and 125.2 mm/s). The limitations of waist angle, waist angle speed and the acceleration are also obtained.

This paper analyzes and summarizes the research status of speed and angle during safe and comfortable standing of elderly people, which is essentially a prerequisite for the elderly to achieve a comfortable STS. These results can lay the foundation for the development of assistive devices and related technologies that meet the needs of older adults.

Today, the demand for renewable energy investments is increasing due to the increase in the world population and the rapid depletion of resources. Renewable energy investments are seen as an area that requires more technical knowledge and experience than nonrenewable energy investments. For this reason, qualified workforce is important in this field. The aim of our study is to reveal the criteria by which renewable energy investments are effective on qualified labor supply. According to the results of our study, in which the analytic hierarchy process method was used, the criterion with the highest weight was determined as “harmonizing universities with undergraduate and graduate level education and internship opportunities.” When this criterion is taken into account, the implementation of policies toward university education in this field together with the renewable energy investments of the countries will positively affect the qualified labor supply.

Selective laser melting (SLM) enables the fabrication of lightweight and complex metallic structures. Support structures are required in the SLM process to successfully produce parts. Supports are typically lattice structures, which cost much time and material to manufacture. Besides, the manufacturability of these supports is undesirable, which may impact the quality of parts or even fail the process. The purpose of this paper is to investigate the efficiency and mechanical properties of advanced internal branch support structures for SLM.

The theoretic weight of a branch support and a lattice support of the same plane were calculated and compared. A group of standard candidates of branch support structures were manufactured by SLM. The weight and scanning time of specimens with different design parameters were compared. Then, these samples were tested using an MTS Insight 30 compression testing machine to study the influence of different support parameters on mechanical strength of the support structures.

The results show that branch type supports can save material, energy and time used needed for their construction. The yield strength of the branch increases with the branch diameter and inclined branch angle in general. Furthermore, branch supports have a higher strength than traditional lattice supports.

To the best of the authors’ knowledge, this is the first work investigating production efficiency and mechanical properties of branch support structures for SLM. The findings in this work are valuable for development of advanced optimal designs of efficient support structures for SLM process.

In this paper, the uncertainties important components and the structure status are obtained by using the condition monitoring, expert groups and multiple membership functions by creating a fuzzy system in MATLAB software.

In the form of fuzzy type, the average structural safety must be followed to replace the damages or to absolutely control the decision-making. Uncertainty in the functionality of hydraulic automated guided vehicles (AGVs), without knowing the reliability of pieces, can cause failure in the manufacturing process. It can be controlled by the condition monitoring pieces done by measurement errors and ambiguous boundaries.

As a result, this monitoring could increase productivity with higher quality in delivery in flexible manufacturing systems with an increase of 70% reliability mutilation for the hydraulic AGV parts.

Hydraulic AGVs play a vital role in flexible manufacturing in recent years. Lately, several strategies for maintenance and repairing of hydraulic AGVs exist in the industry but are still confronted with many uncertainties. The hydraulic AGV is faced with uncertainty after 10 years of working in terms of reliability. Reconstruction of the old parts with the new parts may not have the quality and durability.

This paper aims to clarify the predicting and compensating method of aeroplane assembly. It proposes modeling the process of assembly. The paper aims to solve the precision assembly of aeroplane, which includes predicting the assembly variation and compensating the assembly errors.

The paper opted for an exploratory study using the state space theory and small displacement torsor theory. The assembly variation propagation model is established. The experiment data are obtained by a real small aeroplane assembly process.

The paper provides the predicting and compensating method for aeroplane assembly accuracy.

This paper fulfils an identified need to study how the assembly variation propagates in the assembly process.

Preprint has become an important vehicle for academic communications and discussions. However, in preprint, there is a lack of a sufficient quality control mechanism such as peer review, which is a proven quality assurance practice that is used in traditional academic publishing services. To address the problem leveraging on the power of this practice, the authors introduce into preprint a self-organizing peer review method by applying the concept of token economy and the blockchain technology.

Specifically, this paper proposes an idea that applies the token economy concept to the design of the incentive and penalty mechanisms for peer reviewers in preprint to assure the qualities of its publications. Steemit has been studied to demonstrate the characteristics of the mechanisms.

A token economy-enhanced framework for self-organizing peer review in preprint is also proposed. The resulting preprint system is an academic community-oriented, self-organizing and blockchain-based content publishing system that is designed to run on both permissioned and permissionless blockchains.

First, since peer review is on a voluntary basis and not profits oriented, the “monetary” incentive and penalty mechanisms borrowed from Steemit may conflict with academic ethics. Second, the authors proposed to deploy the authors’ token economy on blockchain, but the current mainstream decentralized blockchain services are too few to warrant a foreseeable successful future for the authors’ application. In fact, as the flagship of blockchain 2.0, the Ethereum blockchain suffers from the problem of scalability, which leads to its applications' lower performances, longer response times and eventually more negative user experiences as time goes by. Finally, the authors’ proposed version of preprint has not been implemented, and hence, its practical effectiveness and acceptance by academia are yet to be evaluated.

In this paper, the authors proposed a token economy-based framework for self-organizing peer review in preprint leveraging on blockchain technology. This framework encourages positive interactions between authors and reviewers, which helps to establish a healthy academic ecology that produces more contents with better qualities. Application of a solution based on the authors’ framework should impact the current academic communities by offering a new academic peer reviewing tool that has a built-in mechanism for self-behavior correction and quality assurance.

Through adaption, the framework can be applied to other domains as well. In such domains, a large amount of feedbacks from partakers are needed and there exists a tremendous amount of work to filter noises in feedbacks so as to ensure that as many the quality ones as possible are delivered for a variety of purposes. The authors’ framework essentially impacts almost all domains where there exists a need to collect and filter large amount of feedbacks, and using the authors’ framework-based solution is cost-saving, which can be seen as a major potential contribution of the research.

The incentive and penalty mechanisms encourage positive interactions between authors and reviewers, and it helps to establish a healthy academic ecology that produces high-volume contents with good qualities.