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Drawing on a 2.5-year ethnography of first-time founders in a coworking facility, I shed light on the process by which founders ascribe self-referential meaning to entrepreneurship—that is, how they develop an entrepreneurial identity in situ. I discovered that founders' use of the coworking space occasioned distinct interaction patterns. Over time, varying interactions played a central role in whether the workspace became a community or remained a mere office space to these founders. Such emergent spatial meanings were coupled with whether founders themselves developed as entrepreneurs or not within their workspace. Founders' perceptions of the workspace as a community were generally associated with their identifying more as entrepreneurs, while their perceptions of the workspace as an office were usually linked with their identifying less, and even disidentifying, as entrepreneurs. In explaining these dynamics, I contribute to research on identity and space, research on entrepreneurial identity, and broader scholarship on space and interactions in organizations. For first-time founders, the meanings associated with being an entrepreneur can be equivocal, and where they work helps to shape their answers to the questions "What is entrepreneurship to me?" and "Who am I?" [ABSTRACT FROM AUTHOR]

This paper offers a comprehensive investigation into the forward and inverse kinematics of a wrist rehabilitation robot, utilizing the Denavit-Hartenberg method for forward kinematics (FK) and a geometric approach, as well as artificial neural networks (ANN) and adaptive Neuro-Fuzzy inference systems (ANFIS) for inverse kinematics (IK) analysis. While the geometric method entails precise parameter measurements and faces uncertainties, ANN and ANFIS are explored as potential remedies to enhance accuracy and robustness. Evaluating 11 different training functions sourced from existing literature, our study conducts a thorough assessment of their performance within an ANN network. We aim to pinpoint the most suitable training function for achieving optimal IK solutions in the context of a wrist rehabilitation robotic. Additionally, the ANFIS model, trained using Fuzzy C-Means (FCM), sets itself apart from Grid Partitioning (GP) and Subtractive Clustering (SC). Among the ANN training functions, Bayesian regularization with 5 hidden layers emerges as the most effective, yielding low root mean square error (RMSE) values of 0.003, 0.004, and 0.007 degrees for pronation/supination (P/S), abduction/adduction (AB/AD), and flexion/extension (F/E), respectively. Conversely, ANFIS, trained with FCM, demonstrates satisfactory yet less precise results, with RMSE values of 0.191, 0.082, and 0.165 degrees for P/S, AB/AD, and F/E, respectively. Despite its adequacy, ANFIS trails behind ANN, showcasing RMSE reductions of 98.4%, 95.1%, and 95.7% for P/S, AB/AD, and F/E angles, respectively. This study contributes to leveraging ANN and ANFIS for IK analysis in wrist rehabilitation robotics, highlighting the efficacy of ANN, particularly when employing Bayesian regularization, to enhance accuracy. [ABSTRACT FROM AUTHOR]

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In rigid lower-mobility parallel manipulators the motion of the end-effector is partially constrained due to a combination of passive kinematic pairs and rigid components. Translational mechanisms, such as the Delta manipulator, are the most common ones among this type of mechanisms. When flexible elements are introduced, as in Parallel Continuum Manipulators, the constraint is no longer rigid, and new challenges arise in performing certain motions depending on the degree of compliance. Mobility analysis shifts from being purely a geometric issue to one that heavily relies on force distribution within the mechanism. Simply converting classical lower-mobility rigid parallel mechanisms into Parallel Continuum Mechanisms may yield unexpected outcomes. This work, making use of a planar parallel continuum Delta manipulator, on the one hand, presents two different approaches to solve the Forward Kinematics of planar continuum manipulators, and, on the other hand, explores some challenges and issues in assessing the resultant workspace for different design alternatives of this kind of flexible manipulators. [ABSTRACT FROM AUTHOR]

Using data collected from focus groups with traditional college students, this paper examines how students read images of highly aestheticized workspaces. The findings demonstrate that although college students are attracted to the aesthetic of workspaces, they are also skilled at reading the affordances present in workspaces. Through experiences like internships, college life, and observations of their parents, students have learned what kinds of affordances support their preferred workstyle and future career. When interpreting images of aestheticized workspaces, they look past the decontextualized aesthetic to understand whether these workspaces are practical for their anticipated work. This research contributes to the literature on how affordances communicate, considers how organizational spaces communicate beyond organizations themselves, and practically suggests how organizations might favor function over design in workplaces to recruit and retain Gen Z workers. [ABSTRACT FROM AUTHOR]

In the field of rigid parallel manipulators, the Delta parallel robot is one of the most popular choices in the industry due to its ability to adapt to a wide range of applications, particularly pick-and-place tasks. In this paper, the authors present novel designs of Delta-type continuum parallel manipulators with flexible bars, solving both their direct and inverse kinematics, as well as obtaining the associated workspace. The continuum parallel manipulators, unlike conventional robots, incorporate certain flexible elements, such as slender rods that make up the kinematic chains of the Delta manipulators proposed in this work. As a consequence of the flexibility of these rods, a purely translational movement will not be generated, since it is necessary to analyze the zones of the workspace where a parasitic motion related to the inclination of the moving platform compromises the task devised. In addition, an experimental prototype of the Keops-Delta continuum manipulator has been built, and several experimental tests have been carried out to validate the proposed theoretical model. [ABSTRACT FROM AUTHOR]

This paper presents a novel parallel manipulator capable of generating two translations (2T), inside a vertical plane, and two rotations (2R), about horizontal axes, which are required in aerospace, manufacturing and rehabilitation fields. These four degrees of freedom are reached by means of a unique RRU and three RSS kinematic chains connected to a rhomboid-shaped mobile platform. The kinematic analysis of the new manipulator is provided, which includes the resolution of the inverse position problem and the velocity equations relating to input and output variables. Additionally, a methodology is proposed for obtaining the workspace free of singularities, collisions and kinematic joint range limitation. This systematic methodology allows designers to identify the critical factors affecting the workspace and, thus, to rearrange the mechanical design accordingly for optimum path planning. We represent the workspace using its two-dimensional subspaces (i.e., translational and rotational workspace). The results are analyzed for different working modes of the manipulator to see its potential use in applications wherein 2T2R motion is necessary. [ABSTRACT FROM AUTHOR]

This paper examines the ethical issues of the inclusion of workers with disabilities in the workplace with a cross-fertilization approach between organization studies, the ethics of care, and a movement from the field of architecture and design that is called Universal Design (UD). It explores how organizations can use UD to develop more inclusive workplaces, first by applying UD principles to workspaces and second by showing how UD implies an integrative understanding of inclusion from the workspace to the workplace. Moreover, this paper discusses the ethical challenges and complexities that this design practice faces in regard to its applicability to diverse organizations and industries. Finally, this paper demonstrates that inclusion requires abandoning any notion of a perfect, productive body and, therefore, recognizing our shared vulnerability and fundamental interdependence in the workplace. [ABSTRACT FROM AUTHOR]

The parallel mechanism with the mixed motion of moving and rotating has high research and application value. The mechanism based on transfer mixed output motion has a wide range of applications, but the design of this kind of mechanism is difficult. In order to develop and popularize the parallel mechanism, a parallel mechanism with one translation and two rotations (1T2R) was designed based on a planar five-bar mechanism and an unconstrained branch chain. Firstly, the topological structure of the parallel mechanism was analyzed according to the position and orientation characteristic (POC) equation, and the degree of freedom (DOF) of the parallel mechanism was calculated. Then, the kinematics of the parallel mechanism was modeled, and the analytic expression of the forward and inverse position solutions was derived. The singularity of the parallel mechanism was analyzed based on Jacobian matrix. The workspace of the parallel mechanism was calculated by using three-dimensional discrete search method, and the dexterity distribution of the parallel mechanism in the workspace was given. Finally, particle swarm optimization ( PSO) was used to optimize the workspace and dexterity of the parallel mechanism, and the influence of unconstrained branch chain layout angle φ on the workspace and dexterity of the parallel mechanism was discussed. The research results show that, the designed 1T2R parallel mechanism has simple structure and position analytical solution. The workspace and dexterity of the optimized parallel mechanism are respectively improved by 93. 47% and 203. 42% . When the driving direction of the unconstrained branch chain is vertically arranged with the planar (2P-3R) mechanism, better motion performance can be obtained. The result lays a theoretical foundation for the practical application of the 3-DOF 1T2R mechanism. [ABSTRACT FROM AUTHOR]

Contact with nature is believed to enhance mental health through the process of human psychological restoration. However, prolonged indoor living limits individuals' exposure to nature, potentially hindering the timely alleviation of stress and fatigue induced by work. While biophilic design is recognized as a potential solution, its impact on the restoration process has not been extensively studied, particularly in relation to its various design patterns. Therefore, it is important to determine the restorative effects of different patterns of biophilic design and their combination in order to guide the practical application of biophilic design. In this study, the effects of two typical biophilic design patterns and their combination on attention restoration were measured using subjective scales, cognitive tasks, and functional near-infrared spectroscopy (fNIRS) in a simulated real workspace. The results suggest a significant enhancement in the restorative impact on cognitive performance and physiological benefits when combining two biophilic design patterns, while a single design pattern does not yield the same effect. These findings contribute to a better understanding and improvement of workspaces, enhancing users' experience and well-being. [ABSTRACT FROM AUTHOR]

The parallel mechanism exhibits high stiffness and excellent dynamic response, making it ideal for high-precision applications. In our early work, a novel 6-DOF redundant parallel posture mechanism with four limbs for solar wing docking has been proposed; each limb consists of three links and four joints. This paper primarily focuses on optimization design of the mechanism. The calculation of workspace volume reveals that factors influencing the range of posture adjustment include dynamic platform parameters, static platform parameters, the drive trajectory of each kinematic pair, and the angles between each kinematic pair. A sensitivity analysis was conducted to examine the impact of each parameter on the range of posture adjustment. To reduce computational complexity and improve analysis efficiency, a combined approach of single-factor analysis and response surface methodology (RSM) is used in the paper. Single-factor analysis is utilized to evaluate the effect of each parameter on the posture adjustment range. Based on these results, RSM is used to establish a regression model for parameters; thereby, the optimal parameter combination for the mechanism is determined. The regression coefficient R2 = 0.9374 attests to the validity of the proposed model. Finally, a comparison of the posture adjustment range before and after optimization is presented, providing a foundation for the practical application of the redundant parallel mechanism. This paper introduces a novel structural design concept aimed at resolving the conflict between heavy loads and compact sizes in redundant parallel mechanisms while providing valuable insights for miniaturized design. [ABSTRACT FROM AUTHOR]

This paper introduces a new concept of a zero-platform delta robot with three key parameters affecting the shape and size of the workspace. This concept is applied to directly bring the torus configuration into the links of the robot and shows its usefulness in configuring and generating the workspace conveniently. Analyzing the workspace of parallel robots, such as delta robots, requires extensive computation due to the constraints between the links, typically requiring complex equations or numerical methods. This paper proposes a new method for quickly estimating the shape and size of the workspace using a cross-section diagram based on a geometrical analysis of the zero-platform delta robot. The shape and size of the workspace can be rapidly estimated because the intersection of three cross-section diagrams needs only the torus's 2D operation. Comparing the workspace between the cross-section diagram and the 3D CAD software, this paper shows that the cross-section diagram can analyze the shape and size of the workspace quickly and give a more geometrical understanding of the workspace. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Architecture & Life Journal / Kocaeli Üniversitesi Mimarlık ve Yaşam Dergisi is the property of Architecture & Life Journal / Kocaeli Universitesi Mimarllik ve Yasam Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, people tend to spend more time indoor, especially in the home and office environment. Indoor air pollution such as CO2 is prevalent in domestic rooms because it is emitted mostly from human metabolism and daily activities such as cooking. This study aims to examine the change of CO2 concentration in the office of company providing logistic services located in Gresik (Indonesia) as a response to phytoremediation and evaluate the effectiveness of selected ornamental plants in controlling CO2 level. The study employed two plants species namely Maranta leuconeura E. Morren and Epipremnum aureum (Linden & André) G. S. Bunting to be placed in the first floor whereas the similar rooms in second floor were used as a control (without plants). The CO2 level in all rooms have previously been measured and compared to quality standard. The required quantity of each plant was calculated based on CO2 pollution load, office dimension, and CO2 removal rate of plants. The presence of plants did not reduce CO2 levels in the studied offices. In none of the offices with plants CO2 concentrations dropped to the recommended levels. However, the plants maintained relatively stable CO2 concentrations, unlike offices without plants, where the concentrations fluctuated and single peaks of increased concentrations were recorded. Room characteristics, exposure to sunlight, placement location of plants, and other external factors may affect efficiency of indoor phytoremediation. [ABSTRACT FROM AUTHOR]

In construction projects, when resources assigned to two or more simultaneous activities share the same workspace, they generate time-space conflicts associated with congestion, safety, and quality issues. The use of building information modeling (BIM) methodologies, particularly four-dimensional (4D) models, offers the possibility to facilitate the identification of these types of conflicts. Existing literature has proposed formal methods for conflict detection; however, these largely focus on automating computational analyses without providing a practical and useful procedure for planners. Moreover, previous research has not evaluated the impact of using formal conflict detection methodologies. To address these gaps, this study proposes and evaluates the use of a formal conflict detection methodology in workspaces based on 4D-BIM. The research methodology includes a first stage that develops and validates the formalized conflict detection methodology through a literature review and interviews with field professionals. The second stage quantifies the impact of using the proposed methodology through an experiment that compares the effectiveness and efficiency of a group of planners in detecting conflicts using 4D-BIM models with and without the proposed methodology. The results demonstrate that the formalized methodology enhances the planning process by increasing the detection of conflicts from 18% to 82%. Additionally, the formalized methodology reduces review time by 23% and enhances user experience. These findings contribute to improving the planning process by managing and reducing time-space conflicts in construction schedules. Consequently, the construction process will become more efficient by averting issues related to productivity, safety, and quality based on the identification of workspace conflicts. Last, the proposed methodology contributes to a better adoption of BIM by providing a structured procedure for using the 4D-BIM model to support planning processes. Practical Applications: This study lays the groundwork for companies aiming to enhance their conflict detection processes and refine planning and conflict management procedures. The practical contributions include achieving greater effectiveness and efficiency in identifying conflicts in workspaces. The proposed formalized methodology enhances productivity, reduces safety-related risks, and prevents quality issues in building projects by managing and mitigating time-space conflicts in construction programs. Additionally, the research contributes to the enrichment of BIM application in construction activity planning. It formalizes the use of BIM through a conflict detection methodology, particularly in the analysis of construction programs and the identification of workspace conflicts. The results further strengthen the application of the BIM methodology by facilitating the design of BIM processes associated with planning, incorporating the methodology proposed in this research. Furthermore, the study encourages the adoption of BIM in construction activity planning by evaluating the positive impact of the proposed formalized methodology, providing evidence for its implementation in organizations and highlighting its potential benefits in terms of effectiveness and efficiency. [ABSTRACT FROM AUTHOR]

Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Accurate determination of the inverse kinematics for the drilling arm of a drilling and anchoring robot is crucial in achieving automatic support in coal mine roadways. Addressing issues such as poor accuracy, limited real-time performance, and susceptibility to local optima, this study presents a novel approach for solving the inverse kinematics problem of an unconventional mechanical arm by combining Monte Carlo random sampling method and Newton iteration method. Initially, a kinematics model is established based on the structure of the drilling arm, and individual coordinate systems are defined for each joint to enable forward kinematics solutions. The Monte Carlo method is employed to determine the motion space of the drill boom. By subdividing the motion space into smaller cubes with a defined step size, a mapping relationship is established between the spatial coordinates of these cubes and the corresponding joint variable values. Using the transformation matrix associated with a given target space point, an index function is employed to identify the relevant small cubes. The points within these cubes, which are closest to the target space point, are calculated, and their corresponding joint variable values are used as initial values. The Newton iteration method is then introduced, utilizing the iterative formula for multivariate functions to determine the variation of each joint variable. The inverse kinematics solution for the unconventional manipulator is obtained through iterative cycles. The simulation results show that, compared with Newton-Raphson iterative method based on random initial values and the particle swarm optimization algorithm, the corresponding average angle error of the calculation results of this method is reduced by 64.98% and 57.34%, and the average time consumption is reduced by 35.90% and 22.33%, respectively, thereby enhancing solution accuracy and real-time performance. The feasibility and effectiveness of the proposed Monte Carlo and Newton iteration method for solving the inverse kinematics problem in unconventional manipulators are verified. Overall, this research provides evidence supporting the practicality and efficiency of the proposed Monte Carlo random sampling method and Newton iteration method for accurate inverse kinematics solutions in unconventional manipulators.

A novel six-degree-of-freedom (6-DOF) parallel manipulator (PM) with a 6- P SS configuration is designed as a piston error compensation mechanism in an optical system. To meet the high-precision adjustment requirement, the prismatic hinges are driven by nanometer resolution piezoelectric motors, and hyperbolic–elliptic (H-E) flexure hinges are used as spherical hinges because of their zero clearance and greater precision transmission capability than traditional rigid hinges. The analysis of the closed-loop vector relationship of the kinematic chain of the leg results in the construction of the kinematic equation, which can satisfy the inverse kinematic solution within a certain precision. The Newton–Raphson method is used for the iteration to solve the forward kinematics. A kinematic simulation was performed to verify the accuracy and effectiveness of the kinematic model using the rigid–flexible coupling finite element method. The workspace of the PM was analyzed using inverse kinematics and kinematics simulation. Two test systems were constructed to test the working performance of the PM. The experimental tests demonstrated that the resolution reached the nanometer level and the travel reached the millimeter level. • A 6- P SS parallel manipulator is proposed whose precision can reach nanometer level. • The kinematics model of the parallel manipulator is established. • A hyperbolic-elliptic flexure hinge with good motion accuracy is proposed. • A theoretical model is established to assess different types of flexure hinges. [ABSTRACT FROM AUTHOR]

The 6-branch chain parallel platform has complex positional constraints and is prone to damage to the mechanical structure when the control algorithm fails. Therefore, the kinematic operability and workspace of a 3UPU-UP parallel platform was analysed. Firstly, the kinematic model of the 3UPU-UP parallel platform was derived through the analysis of vector method and kinematics, based on which, the evaluation index of the operability of the tandem robotic arm was firstly combined with the characteristics of the mechanism structure of the 3UPU-UP parallel platform. The operability of the 3UPU-UP parallel platform was computed, analyzed and visualized. The Monte-Carlo method was combined with the orthogonal kinematics to analyze the workspace of the 3UPU-UP parallel platform. The Monte-Carlo method and positive kinematics were combined to calculate, analyze and visualize the workspace of the parallel platform. The workspace of the parallel platform can be expressed more intuitively and completely. The research results provide the theoretical basis for the design of the 3UPU-UP parallel platform and confirm its theoretical feasibility. [ABSTRACT FROM AUTHOR]

The geological sedimentation simulation platform is an important device for quantitatively studying geological sedimentation theory. In order to meet the research needs of large-scale, refined, and quantitative sedimentation simulation, a geological sedimentation simulation platform that can perform all-round attitude adjustment motion based on a 4-PSE parallel mechanism was designed, and its kinematic characteristics were studied. Combined with the working principle of the simulation platform, the degrees of freedom of the 4-PSE parallel mechanism were calculated, and the Kinematics equations of the simulation platform were derived. The virtual prototype model of the simulation platform was established in ADAMS software, and its Kinematics parameters were theoretically verified using the Kinematics simulation results. The workspace constraints of the simulation platform was analyzed, its workspace was obtainecl, and the influence curve of relevant structural parameters on the workspace was drawn. The research results provide a theoretical basis for the structural design optimization of subsequent geological sedimentation simulation platforms and the combination of multiple platforms. [ABSTRACT FROM AUTHOR]

Hand dysfunction is a common symptom in stroke patients. This paper presents a robotic device which assists the rehabilitation process in order to reduce the need of physical therapy, i.e., a 3UPS/S parallel robotic device is employed for repetitive robot-assisted rehabilitation. Euler angle representation was used to solve the robot's inverse kinematics. The robot's joint space and rotational workspace were determined for two scenarios. In the first scenario, the workspace was obtained considering the actuator's stroke limitations, while in the second scenario, the workspace was determined by adding a second condition, i.e., the range of motion of the spherical joints. Singularity analysis was performed using the geometric algebra approach. The robot was manufactured using additive manufacturing technology. The solution of the inverse kinematic problem was employed to control the robot. The robot can perform a full range of motion during wrist ulnar deviation and radial deviation motions, with the exception of limited wrist flexion and extension motions. The robot has singular configurations within its workspace. Although the spherical joints have roles in reducing the workspace, the primary causes are actuator selection, radii of the base and moving platforms, and the length of the central leg. These factors can be considered to improve the workspace. Singularity can be avoided by carefully selecting the rotation of the moving platform about the Z-axis and avoiding same leg lengths. [ABSTRACT FROM AUTHOR]

This contribution focuses on solving the inverse and forward kinematics in the kinematic analysis of a two-link manipulator model. It involves determining the trajectory of the end effector through fifth-degree polynomial interpolation. Furthermore, given initial and final arm angle values, it computes not only the end effector trajectory but also the angular parameters of individual actuators in both arms. Additionally, it calculates the variations of angular parameters such as rotation angle, angular velocity, and angular acceleration in each kinematic pair. The direct kinematics task is utilized to define the manipulator's workspace. The task is carried out using Matlab software, and the results are presented in the form of graphs and tables. [ABSTRACT FROM AUTHOR]

Compared with single rigid serial robots (RSRs) and cable-driven parallel robots (CDPRs), cable-driven hybrid robots (CDHRs) have the advantages of both CDPRs and RSRs, which can improve the deficiencies of a single robot in one aspect. Due to a larger force-enclosed workspace (FEW), CDHRs can accomplish more complex tasks, which have a wide range of applications in industrial picking, disaster rescue, construction renovation, etc. However, as its structural complexity increases, the coupling modeling and workspace analysis will become more difficult. Based on this, this paper provides a coupled kinematics, statics modeling, and workspace analysis method of CDHRs. Firstly, the forward/inverse kinematic equations of the series/parallel coupling are derived, and the corresponding solutions are given according to this composite structure with high redundancy. Secondly, the static equations of the CDHR are further derived based on the coupled kinematics model and solved by the quadratic programming method (QPM). Further, a FEW for the CDHR is established based on collision constraints, containing the workspaces of both the RSR and the CDPR. To evaluate the quality of the workspace for the CDHR, a method for solving the configuration flexibility is proposed. Finally, the workspace and the configuration flexibility of the CDHR are analyzed by the built simulation system. And then, the tracking methods of several typical trajectories are verified by the model. [ABSTRACT FROM AUTHOR]

Purpose: In today’s world many companies fell the need to move especially their leaders from traditional leadership into a more person cantered approach, which is clearly defined by Social Psychology of Risk. The pioneering methodology was invented to support personhood, care for ethics and promote an appropriate culture of an organization. The following article explains the fundamentals of Social Psychology of Risk, as well as underlines its definitions about leadership. Material shows original aspects of understanding some of the most important roles humans might take upon themselves not only as leaders, but also as employes in any organization or field of work. Design/methodology/approach: The paper uses the desk research method of analysis. Findings: Today’s leadership. Social implications: Many aspire to be great leaders; however, not many are on the pathway of receiving value adding answers regarding the matter. Originality/value: The article is an original approach to understand some of the most efficient ways to create a great leadership, mostly submerged in the fundamentals of Social Psychology of Risk and that all being explained while using a Newton’s cradle and a “jar of time”. [ABSTRACT FROM AUTHOR]

The D-H parameter method has found extensive application in the analysis of manipulator motion. However, it primarily describes motions along the x and z axes, neglecting the y-axis motion. To address this limitation, the present study employs the screw theory method to represent the manipulator's position and orientation as a screw, conducting an in-depth analysis of its kinematics and dynamics. In contrast to the traditional D-H approach for forward kinematics, screw theory offers a holistic depiction of the robot arm's motion, eliminating the necessity for an intermediate reference system with explicit geometric significance. To tackle the inverse kinematic problem of the elbow robotic arm, the Paden-Kahan subproblem is applied, resulting in the computation of an inverse kinematics solution. Leveraging screw theory and Lie group-Lie algebra, the Newton-Euler approach is employed to construct an efficient recursive dynamic model. Ultimately, the manipulator's inverse kinematic solution derived through the screw theory is subjected to simulation and verification, with its workspace calculation revealing that the screw theory method offers a more concise, accurate, and effective approach. [ABSTRACT FROM AUTHOR]

Existing direct and inverse kinematic models of planar parallel robots assume that the robot's active joints are all at the bases. However, this approach becomes excessively complex when modeling a planar parallel robot in which the active joints are within one single kinematic chain. To address this problem, our article unveils an alternative for a 3RRR symmetric planar robot modeling technique for the derivation of the robot workspace and the analysis of its direct and inverse kinematics. The workspace was defined using a system of inequalities, and the direct and inverse kinematics models were generated using vectorial analysis and an optimized geometrical approach, respectively. The resulting models are systematically presented and validated. Two final model renditions are delivered supplying a thorough equation analysis and an applicability discussion based on the importance of the robot's mobile platform orientation. The advantages of this model are discussed in comparison to the traditional modeling approach: whereas conventional techniques require the solution of complex eighth-degree polynomials for the analysis of the active joint configuration of these robots, these models provide an efficient back-of-the-envelope analysis approach that requires the solution of a simple second-degree polynomial. [ABSTRACT FROM AUTHOR]

There is an unbalanced problem in the traditional laneway excavation process for coal mining because the laneway excavation and support are at the same position in space but they are separated in time, consequently leading to problems of low efficiency in laneway excavation. To overcome these problems, an advanced dual-arm tunneling robotic system for a coal mine is developed that can achieve the synchronous operation of excavation and the permanent support of laneways to efficiently complete excavation tasks for large-sized cross-section laneways. A dual-arm cutting robot (DACR) has an important influence on the forming quality and excavation efficiency of large-sized cross-section laneways. As a result, the relative kinematics, workspace, and control of dual-arm cutting robots are investigated in this research. First, a relative kinematic model of the DACR is established, and a closed-loop control strategy for the robot is proposed based on the relative kinematics. Second, an associated workspace (AW) for the DACR is presented and generated, which can provide a reference for the cutting trajectory planning of a DACR. Finally, the relative kinematics, closed-loop kinematic controller, and associated workspace generation algorithm are verified through simulation results. [ABSTRACT FROM AUTHOR]