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Stiffness control of redundant robot arm, aimed at using extra degrees of freedom (DoF) to shape the robot tool center point (TCP) elastomechanical behavior to be consistent with the essential requirements needed for a successful part mating process, i.e., to mimic part supporting mechanism with selective quasi-isotropic compliance (Remote Center of Compliance – RCC), with additional properties of inherent flexibility.

Theoretical analysis and synthesis of the complementary projector for null-space stiffness control of kinematically redundant robot arm. Practical feasibility of the proposed approach was proven by extensive computer simulations and physical experiments, based on commercially available 7 DoF SIA 10 F Yaskawa articulated robot arm, equipped with the open-architecture control system, system for generating excitation force, dedicated sensory system for displacement measurement and a system for real-time acquisition of sensory data.

Simulation experiments demonstrated convergence and stability of the proposed complementary projector. Physical experiments demonstrated that the proposed complementary projector can be implemented on the commercially available anthropomorphic redundant arm upgraded with open-architecture control system and that this projector has the capacity to efficiently affect the task-space TCP stiffness of the robot arm, with a satisfactory degree of consistency with the behavior obtained in the simulation experiments.

A novel complementary projector was synthesized based on the adopted objective function. Practical verification was conducted using computer simulations and physical experiments. For the needs of physical experiments, an adequate open-architecture control system was developed and upgraded through the implementation of the proposed complementary projector and an adequate system for generating excitation and measuring displacement of the robot TCP. Experiments demonstrated that the proposed complementary projector for null-space stiffness control is capable of producing the task-space TCP stiffness, which can satisfy the essential requirements needed for a successful part-mating process, thus allowing the redundant robot arm to mimic the RCC supporting mechanism behavior in a programmable manner.

Conventional approaches of evaluating spatial layout configurations typically involved universal understandings of aspects like connectivity, proximity and visibility, while possibly discarding both partially true solutions and ranges of parameters affecting detailed spatial relations. With the growing need to address spatial uncertainty and ambiguity, the incorporation of methods that embrace soft qualities in design is becoming increasingly significant in spatial layout planning.

The authors introduce a fuzzy-based approach for the automated assessment of architectural spatial layout configurations while addressing ambiguity in layout design. The authors evaluate soft interdependent design qualities like connectedness, enclosure and spaciousness to satisfy multiple mutually inclusive criteria and account for all logical solutions without discarding likely or less likely solutions. The authors analyze spatial entities, parameters and relations and identify rulesets for logical configurations using linguistic variables, fuzzy sets, membership functions and descriptive rule blocks. As a case study, the authors use grasshopper and fuzzyTECH to represent four pilot layout alternates with varying attributes and a case study focusing on one specific spatial criterion.

Multiple complex and nuanced spatial relations were inferred by evaluating spatial outputs and their inherent discrepancies and correlations, thus confirming the assumption that fuzzy-based systems could potentially satisfy multiple mutually inclusive criteria and account for exhaustive logical solutions without discarding preferable, likely or less likely solutions.

Most precedent approaches focus on spatial layout design from an occupancy-centered perspective, where occupancy patterns and possibilities are identified in loosely defined spaces or behavioral usage patterns. The added value in this paper involves including a wide array of spatial inputs to describe soft spatial qualities using nuanced rule-based descriptors.

Whilst Hong Kong is suffering from a limited supply of developable land in its major urban areas, some open spaces are frequently criticized as inconvenient for users, consequently leading to an ineffective use pattern. How to enhance the performance of open space is therefore a critical issue faced by city planners. As the conventional accessibility model, which is mainly described with respect to maximum walking distance or service radius, is inadequate to give an account of the issue, this paper accordingly indicates an alternative approach and seeks an explanation from the urban configuration and the way it conditions pedestrian movement pattern. Through investigating the relationship between urban configuration, pedestrian movement and accessibility and use of open spaces based on the Wanchai District of Hong Kong, which particularly epitomizes various urban grids that may have different consequences on the utilization of open space, this study aims to examine whether there is a consistent relationship existing in different spatial grids or whether the relationship varies from different layout patterns. It is hoped that the findings can be employed to improve the performance of open spaces in the urban areas of Hong Kong, in addition to other similar urban environment.

This paper contains a generalization of the existing theory of Garden of Eden configurations in tessellation automata. We consider spaces of at most two dimensions but with transition functions having arbitrarily large neighborhoods. A configuration c is said to be Garden of Eden of degree n just in case there is no configuration from which c can arise in n time steps; c is Garden of Eden of minimal degree n just in case there is no smaller m such that c is Garden of Eden of degree m. Necessary and sufficient conditions for the existence of Garden of Eden configurations of higher degree (and of degree 1) are established. Results are obtained relating decision procedures for Garden of Eden configurations of degree one to decision procedures for Garden of Eden configurations of higher degree.

This study explores the characteristics of female space evolution in Korean vernacular houses in the Yanbian region of China. In addition, it discusses the influence of social logic on the evolution of female spaces.

This study utilises space syntax methodology to examine the evolution of female spaces in Korean vernacular houses in terms of connectivity value, step depth and integration value. Furthermore, it conducts an analytical exploration of social logic based on the evolutionary characteristics of female space.

The findings elucidate the evolutionary characteristics of the spatial configuration of female spaces in Korean vernacular houses, with differential changes in connectivity, a gradual tendency towards openness and simplicity and increased accessibility and centrality. This reflects the changing spatial needs of Korean women brought about by changes in lifestyle, consciousness, social status and family structure.

This study provides perspectives and insights into the vernacular architecture and architectural sociology of ethnic minorities in regions of China and Asia. Furthermore, it can provide relevant construction organisations with a more intuitive understanding of Korean vernacular houses and a reference for future house renewal and construction in the Yanbian region.

Although many studies have investigated various aspects of Korean vernacular houses and female spaces, none have examined the influence of social logical changes on the evolution of female spaces in Korean vernacular houses. Thus, this study is valuable and novel.

The purpose of this paper is to propose a strategy for the final assembly of helicopter fuselage with weak rigidity parts and mismatched jointing butt ends.

The strategy is based on path planning methods. Compared with traditional path planning methods, the configuration-space and collision detection in the method are different. The obstacles in the configuration-space are weakly rigid and allow continuous contact with the robot. The collision detection is based on interference magnitudes, and the result is divided into no collision, weak collision and strong collision. Only strong collision is unacceptable. Then a compliant jointing path planning algorithm based on RRT is designed, combined with some improvements in search efficiency.

A series of planning results show that the efficiency of this method is higher than original RRT under the same conditions. The effectiveness of the method is verified by a series of simulations and experiments on two sets of systems.

There are few reports on the automation technology of helicopter fuselage assembly. This paper analyzes the problem and provides a solution from the perspective of path planning. This method contains a new configuration-space and collision detection method adapted to this problem and could be intuitive for the jointing of other weakly rigid parts.

Fast obstacle avoidance path planning is a challenging task for multijoint robots navigating through cluttered workspaces. This paper aims to address this issue by proposing an improved path-planning method based on the distorted space (DS) method, specifically designed for high-dimensional complex environments.

The proposed method, termed topology-preserved distorted space (TP-DS) method, mitigates the limitations of the original DS method by preserving space topology through elastic deformation. By applying distinct spring constants, the TP-DS autonomously shrinks obstacles to microscopic areas within the configuration space, maintaining consistent topology. This enhancement extends the application scope of the DS method to handle complex environments effectively.

Comparative analysis demonstrates that the proposed TP-DS method outperforms traditional methods regarding planning efficiency. Successful obstacle avoidance tasks in the cluttered workspace validate its applicability on a physical 6-DOF manipulator, highlighting its potential for industrial implementations.

The novel TP-DS method generates a topology-preserved collision-free space by leveraging elastic deformation and shows significant capability and efficiency in planning obstacle-avoidance paths in complex application scenarios.

The purpose of this paper is to compare the quality and efficiency of five methods for solving the path planning problem of industrial robots in complex environments.

In total, five methods are presented for solving the path planning problem and certain working parameters have been monitored using each method. These working parameters are the distance travelled by the robot and the computational time needed to find a solution. A comparison of results has been analyzed.

After this study, it could be easy to know which of the proposed methods is most suitable for application in each case, depending on the parameter the user wants to optimize. The findings have been summarized in the conclusion section.

The five techniques which have been developed yield good results in general.

The algorithms introduced are able to solve the path planning problem for any industrial robot working with obstacles.

The path planning algorithms help robots perform their tasks in a more efficient way because the path followed has been optimized and therefore they help human beings work together with the robots in order to obtain the best results from them.

The paper shows which algorithm offers the best results, depending on the example the user has to solve and the parameter to be optimized.

The purpose of this paper is to analyse privacy and interaction preferences in the social dimension of individual learning students and how the spatial configuration affects individual learners’ choices of learning spaces.

This empirical survey study was conducted in an Australian university’s informal learning spaces. Space syntax theories are applied to construct a four-quadrant theoretical framework.

The research findings indicate that based on the differences between students in their individual characteristics, there are significant differences in their needs for privacy and interaction. This study reveals that the spatial configuration affects individual learners’ choices of learning spaces.

This study could assist universities in providing students with more effective and diverse informal learning spaces.

This paper aims to investigate the ways that could enhance residents’ social interaction in low-rise residential building neighbourhoods of Basra city in Iraq. The lack of social interaction among residents of Basra city prompted the authors to frame a strategy for this case study.

The spatial design characteristics of low-rise residential building neighbourhoods implicated to support the residents in terms of social interactions in comparison to those exhibited by a single home and traditional neighbourhoods. The statistical data demonstrated that by using this strategy, several unique features of secured, collective, responsive and supportive spaces could enhance the residents’ social interaction.

This study found that all collective space factors have a significant influence on social interaction. “Fostering proper proximity and accessibility” factor was ranked first and the most significant factor with an influence on social interaction. Secured spaces (hierarchical spatial structure, physical security supports and construct) have a significant influence on social interaction. The most interesting finding in this study is that all factors of the supportive spaces construct have a significant influence on social interaction. Finally, this study showed that two factors of the responsive spaces construct, increasing variety and increasing legibility, have an insignificant influence on social interaction.

The design of low-rise residential building neighbourhoods in Basra city may be used to develop social interaction as the contributing factor for maintaining values of traditional neighbourhood communities. This study highlights certain recommendations for architects, especially urban designers, to reinforce residents’ social interaction in low-rise residential building neighbourhoods in Basra city.