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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]

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]

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]

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]

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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.

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]

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]

Aiming at the problem that human beings are prone to fatigue when they repeatedly perform a single action in the performance test of the driver attention monitoring system, a humanoid robot arm is designed to simulate the driver's behaviors such as answering and making handsets and smoking. Firstly, based on the exoskeleton design method, the structure of the robot arm and the bionic hand is designed. Secondly, the improved D-H method is used to establish the kinematics model of the manipulator; the forward and inverse kinematics are solved, and the workspace is analyzed; the dynamics simulation of the robot arm is carried out in Adams software to obtain its motion characteristics and load characteristics. The simulation results show that the structural design of the manipulator is reasonable, and the selection of joint flexible actuators meets the requirements.

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.

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.

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.

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.

Objective: Using the example of robotic-assisted surgery (RAS), we explore the methodological and practical challenges of technology integration in surgery, provide examples of evidence-based improvements, and discuss the importance of systems engineering and clinical human factors research and practice. Background: New operating room technologies offer potential benefits for patients and staff, yet also present challenges for physical, procedural, team, and organizational integration. Historically, RAS implementation has focused on establishing the technical skills of the surgeon on the console, and has not systematically addressed the new skills required for other team members, the use of the workspace, or the organizational changes. Results: Human factors studies of robotic surgery have demonstrated not just the effects of these hidden complexities on people, teams, processes, and proximal outcomes, but also have been able to analyze and explain in detail why they happen and offer methods to address them. We review studies on workload, communication, workflow, workspace, and coordination in robotic surgery, and then discuss the potential for improvement that these studies suggest within the wider healthcare system. Conclusion: There is a growing need to understand and develop approaches to safety and quality improvement through human-systems integration at the frontline of care. Precis: The introduction of robotic surgery has exposed under-acknowledged complexities of introducing complex technology into operating rooms. We explore the methodological and practical challenges, provide examples of evidence-based improvements, and discuss the implications for systems engineering and clinical human factors research and practice. [ABSTRACT FROM AUTHOR]

Given the difficulty in manually adjusting the position and posture of the pile body during the pile driving process, the improved Denavit-Hartenberg (D-H) parameter method is used to establish the kinematics equation of the mechanical arm, based on the motion characteristics of each mechanism of the mechanical arm of the pile driver, and forward and inverse kinematics analysis is carried out to solve the equation. The mechanical arm of the pile driver is modeled and simulated using the Robotics Toolbox of MATLAB to verify the proposed kinematics model of the mechanical arm of the pile driver. The Monte Carlo method is used to investigate the working space of the mechanical arm of the pile driver, revealing that the arm can extend from the nearest point by 900 mm to the furthest extension of 1800 mm. The actuator's lowest point allows for a descent of 1000 mm and an ascent of up to 1500 mm. A novel multi-strategy grey wolf optimizer (GWO) algorithm is proposed for robotic arm three-dimensional (3D) path planning, successfully outperforming the basic GWO, ant colony algorithm (ACA), genetic algorithm (GA), and artificial fish swarm algorithm (AFSA) in simulation experiments. Comparative results show that the proposed algorithm efficiently searches for optimal paths, avoiding obstacles with shorter lengths. In robotic arm simulations, the multi-strategy GWO reduces path length by 16.575% and running time by 9.452% compared to the basic GWO algorithm. [ABSTRACT FROM AUTHOR]

This paper presents the structure and model of a hybrid modular structure of a robotic system for lower limb rehabilitation. It is made of two modules identical in structure, including an active 3-PRRR manipulator for moving the patient's foot and a passive orthosis based on the RRR mechanism for supporting the lower limb. A mathematical model has been developed to describe the positions for the links of the active and passive mechanisms of two modules, as a function of the angles in the joints of the passive orthosis, considering constraints for attaching the active manipulators to the moving platform and their configurations. A method has been formulated for a parametric synthesis of the hybrid robotic system proposed with modular structure, taking into account the generated levels of parametric constraints depending on the ergonomic and manufacturability features. The proposed design is based on a criterion in the form of a convolution, including two components, one of which is based on minimizing unattainable points of the trajectory, considering the characteristics of anthropometric data, and the other is based on the compactness of the design. The results of the mathematical modeling are discussed as well as the analysis results towards a prototype validation. [ABSTRACT FROM AUTHOR]

Laparoscopic manipulation of delicate large intra-abdominal organs is a difficult task that needs special training programs to improve the surgeons' dexterity. In this study, the mechanical design of a robotic interface for haptic simulation of largeorgan laparoscopic surgery is described. The designed robot enjoys active active Degree of Freedoms (DOFs), back drivability, low inertia, friction and backlash, and sufficiently large force/moment production capacity. The kinematics of the robot was analyzed and a functional prototype was fabricated for experimental tests. Results indicated that the target workspace was fully covered with no singular points inside. The mechanism was highly isotropic and the torque requirements were in the acceptable range. The trajectory tracking experiments against a 1 kg payload revealed an Root Mean Square (RMS) of 0.9 mm, due to the simplifications of the kinematic model, i.e., not considering the friction and backlash effects. It was concluded that the designed robot could satisfy the mechanical requirements for being used as the robotic interface in a haptic large-organ laparoscopic surgery simulation system. [ABSTRACT FROM AUTHOR]

WFH‐related issues regarding house planning, spatial arrangements, and relationships among cohabitants for sharing spaces remain to be clarified. This research aimed to clarify the usage patterns of shared spaces for work‐from‐home (WFH) and the respective behavioral patterns in different household compositions, targeting women in the child‐rearing stage and residing with family in residential building estates in urban areas. Forty‐four percent (n = 199) of women performing childcare who regularly telecommuted had a spouse or partner who also telecommuted, and 65.6% (n = 328) had a child at home while telecommuting. Male spouses or partners (male) did less than half of the housework (12.7%) and childcare (19.8%) than women (41.0% housework, 34.4% childcare). Women primarily used dining rooms for office work (n = 221; 44.2%). When the children were at home during telecommuting, the unclear distinction between work and home was not a deficiency but rather an inevitable acceptance, and a tendency to work in a corner overlooking the common area was observed. When both spouses telecommute without children, men work in their bedrooms or private rooms, whereas women work in common areas, such as the dining room. Simultaneously, women tended to seek spaces dedicated to their work and keep their workspaces separate from common area. [ABSTRACT FROM AUTHOR]

In this study, a hybrid type (2-PUR/UPS) &R cervical vertebra rehabilitation machine is proposed for the cervical traction rehabilitation training of patients with cervical spondylosis. The machine has 3R1T four degrees of freedom and meets the requirement of the range of motion of human cervical vertebra. The kinematic performance of the machine is analyzed to verify whether it can be applied in the field of human cervical vertebra rehabilitation. Firstly, the degrees of freedom of the mechanism are solved and verified by using the spiral theory and the modified Kutzbach-Grvble formula. Secondly, by solving the inverse solution of the position of the mechanism, the rod length of the mechanism is deduced, the program of solving the workspace is written, and the workspace of the mechanism is obtained by the numerical search method. Finally, the mechanism is simulated and analyzed by Adams software. The results show that the mechanism could reach the range required for cervical spine movement, including -55° to 35° for forward and backward leaning. Left-handed and right-handed is -52° to 52°; the left and right lateral flexion is -45° to 45°, which can provide traction treatment for patients with cervical spondylosis.

Large complex components are the core structural components of equipment in the fields of aerospace, energy, ships, etc. Such components have large sizes, complex shapes, and high processing accuracy requirements. Nowadays, robotized processing systems can overcome the shortcomings of high cost, poor flexibility of the gantry equipment, which have become a powerful tool for processing large complex components. However, the ontology performance of the existing robotized processing system still has problems such as small workspace and weak load capacity, so a hybrid mechanism that can be used as the core ontology of a large complex component processing robot is proposed in this study. The hybrid mechanism consists of a series of manipulators for processing tasks and a 6-UPS parallel mechanism. The 6-UPS parallel mechanism, driven by six drive rods, is used to support the series manipulator and regulate its position and pose on the one hand, and drive the robot to travel with the hybrid mechanism as the ontology on the other hand. The kinematics modeling and workspace solutions of the serial manipulator, 6-UPS parallel mechanism and the whole hybrid mechanism are completed in this study and it is proved that the workspace of the whole hybrid mechanism is significantly larger than that of the serial manipulator and the 6-UPS parallel mechanism. The virtual prototype of the robot is designed with the proposed hybrid mechanism as the robot ontology. By realizing the gait walking of the virtual prototype in a three-dimensional software, it is proved that the designed robot can further expand the workspace using a walking function.

For patients with lower limb motor hemiplegia, a 1R2T-1R type rope-driven lower limb rehabilitation robot is proposed and its complete model is built based on human lower limb movement patterns. The kinematic forward and inverse solution analysis is carried out for this robot and its correctness is verified. Based on the Monte Carlo method, the controllable workspace and the actual workspace of this robot under the premise of force closure are solved in the Matlab environment and compared. The results show that the rehabilitation robot has a reasonable configuration and its working range can meet the needs of patients' rehabilitation training, which provides some reference for subsequent parameter optimization and trajectory planning.

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.

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.

Aiming at the problems of high labor intensity, high risk factor, long inspection time, low efficiency and wide range of manual inspection of railway catenary, a catenary inspection robot with a telescopic structure is proposed, which can replace manual inspection of the catenary. The overall structure of the robot and the selection of core components are determined. The screw theory and the modern matrix exponential product formula are used to establish the kinematics model; the Matlab Robotics toolbox is used to establish the simulation model and verify the kinematics equation; the Monte Carlo method is used to solve the robot workspace and draw the point cloud map. Finally, Ansys Workbench software is used for finite element analysis of key components, and the strength and stiffness are checked and verified. The designed robot in this study reduces the workload of workers; using lightweight materials and joint modular design makes the mass be reduced by 25%; its terminal multi-degree-of-freedom structure makes the shooting angle and range be increased by 2 times compared with the traditional way; the telescopic structure enables the robot to obtain a larger working space to meet the work requirements.

Based on the topological design theory of a parallel mechanism with orientation feature set and bending translation theory, a new parallel mechanism with circular spherical translation and one rotation (2T1R) with 3 degrees of freedom （DOF） and low coupling is designed and topological characteristics of the mechanism are analyzed, including the orientation feature set, degrees of freedom and coupling calculation. The kinematics of the mechanism is analyzed, and the forward and inverse solutions of the position of the mechanism are solved and verified. Finally, based on the positive and negative equations of the mechanism, the workspace and the rotation capacity distribution of the mechanism are analyzed. The work in this study lays the foundation for the subsequent scale optimization, error analysis and dynamics analysis of the mechanism.

A five degrees of freedom manipulator for automatic retractable vehicle-mounted wheelchairs is proposed. Firstly, the mathematical model of the manipulator is established according to the D-H method, and the forward and inverse kinematics analysis is carried out. When the inverse kinematics analysis is carried out, the analytical method and the back propagation (BP) neural network are used to solve the problem respectively. Secondly, the quintic polynomial interpolation method is used to plan the joint space trajectory of the manipulator, so as to realize the smooth and impact-free movement of the manipulator. Then, the workspace of the manipulator is analyzed based on the Monte Carlo method, and the point nephogram of the workspace for the end positioning of the manipulator is obtained. Finally, virtual simulation experiment is carried out for specific vehicle-mounted application scenarios. The simulation results show that the design of the manipulator is reasonable, the movement is flexible, and it meets the application requirements, which will provide a theoretical basis for the development and application of the prototype.

A 4-CPS/UPU parallel mechanism used in the field of parallel machine tools is proposed. Based on the screw theory, the kinematic and constrained screw system of the parallel mechanism is established. The mechanism has five degrees of freedom and can realize the function of three shifts and two rotations. The degree of freedom is verified by the modified K-G formula. The forward and inverse solutions of the parallel mechanism and the working space are analyzed. The simulation analysis is carried out by Adams software. The workspace of the mechanism is continuous without cavity, and its shape is similar to that of a pyramid, which is regular and symmetrical; the smooth displacement and velocity curves obtained by simulation show that the mechanism has good kinematic performance, which provides a certain theoretical basis for its parametric design in the field of parallel machine tools.

According to the theory and method of topological design of the parallel mechanism (PM) based on position and orientation characteristic (POC) equations, a novel three-translation (3T) parallel mechanism for grasping is proposed. Firstly, the design process of the entire PM is described and the main topological features of the mechanism are analyzed. It is proved that the mechanism contains two sub-kinematics chains (SKCs） whose coupling degree equals 0. Secondly, according to the kinematics modeling principle for parallel mechanism based on topological features, the direct kinematics problem (DKP) and inverse kinematics problem (IKP) of the mechanism are solved according to the order of SKC. Then, according to the singularity analysis method based on SKC theory, the first and second kind of singular configurations in each SKC are analyzed. Finally, the task workspace with the optimal internal velocity transmission factors index of the mechanism is analyzed and selected. This study lays the foundation for the stiffness, dynamics and engineering prototype design of the mechanism.

This paper investigates the pattern of change in occupants’ satisfaction with the Indoor Environmental Quality (IEQ) of their workspace over time. Analyses were performed on a cumulative (2012–2023) database of responses to a Post-Occupancy Evaluation survey in Australia. 20,400 questionnaire responses from 226 office buildings were classified into five groups based on the length of time respondents had occupied their workspace. Associations between workspace satisfaction and the length of time respondents had occupied their workspace were also analysed for different gender and age cohorts. Our results show that occupant satisfaction generally decreased with the length of time they had been allocated to their present workspaces (the ‘honeymoon-hangover’ effect). People who have occupied their workspace for more than 5 years expressed lower overall satisfaction with their workspace than those who have been there for less than 6 months. The same pattern was observed for occupants’ satisfaction with other IEQ dimensions including building image and maintenance, indoor air quality, spatial comfort, and thermal comfort. This ‘honeymoon-hangover’ effect was evident across genders and age groups. Furthermore, there was negligible difference between the two genders on the ‘honeymoon-hangover’ effect, although thermal comfort and indoor air quality were generally less satisfactory for women than men. Respondents aged 30 yrs or less showed a larger decline in satisfaction over time compared to those over 50-yrs old. Within the 30-year-or-under age group, occupants who had spent more than 5 years at their workspaces consistently registered the lowest satisfaction score across all IEQ dimensions. Implications and impacts: The findings in this study have significant implications for the design of Post-Occupancy Evaluation (POE) surveys and for facility managers aiming to enhance occupants' satisfaction with their workspace and workplace.

Abstract WFH‐related issues regarding house planning, spatial arrangements, and relationships among cohabitants for sharing spaces remain to be clarified. This research aimed to clarify the usage patterns of shared spaces for work‐from‐home (WFH) and the respective behavioral patterns in different household compositions, targeting women in the child‐rearing stage and residing with family in residential building estates in urban areas. Forty‐four percent (n = 199) of women performing childcare who regularly telecommuted had a spouse or partner who also telecommuted, and 65.6% (n = 328) had a child at home while telecommuting. Male spouses or partners (male) did less than half of the housework (12.7%) and childcare (19.8%) than women (41.0% housework, 34.4% childcare). Women primarily used dining rooms for office work (n = 221; 44.2%). When the children were at home during telecommuting, the unclear distinction between work and home was not a deficiency but rather an inevitable acceptance, and a tendency to work in a corner overlooking the common area was observed. When both spouses telecommute without children, men work in their bedrooms or private rooms, whereas women work in common areas, such as the dining room. Simultaneously, women tended to seek spaces dedicated to their work and keep their workspaces separate from common area.

This paper aims to assess the effectiveness of incorporating inclined glazing with double low-emissivity (low-e) glazing, in glazed, green-certified office buildings in Malaysia. The study was conducted in an open workspace facing south and west. Comparisons were conducted between measurements made on weekdays when cooling systems were active and weekends when they were not in use. The analysis considered two different zones based on the proximity to the glazed facade: the adjacent zone and the central zone. The thermal performance of the glazed facade and the indoor thermal conditions were measured from July 25th to August 30th. The findings indicate that the building successfully maintains indoor air temperature within the recommended thermal range of 23 °C–26 °C, as specified by the Malaysia Standard. However, it was noted that the air velocity fell below the required level for optimal indoor air circulation. Measuring the globe temperature showed a remarkable difference, with the adjacent zone experiencing 4.1 °C higher temperatures due to radiant heat from the glazing. Additional research is suggested to assess the effectiveness of inclined and double low-e glazing in hot–arid climates like Saudi Arabia.

In view of the problem that the traditional three-degree of freedom series - parallel engraving machine tool is difficult to process the complex surface in space, this study presents a novel type of five- degree of- freedom series - parallel engraving machine tool in space. The three dimensional model of the engraving machine is established in SolidWorks, the mathematical model of position inverse solution and parameter decoupling is established, and the workspace is generated by Monte Carlo method in MATLAB. The analysis of working space shows that the working space of the engraving machine tool is large, which can meet the processing requirements of complex surfaces in the part space to a certain extent. On this basis, through the analysis of the working space of the engraving machine tool, it is found that the suitable method to increase the working space of the new engraving machine tool is to increase the length of the series slide rail. [ABSTRACT FROM AUTHOR]

The paper delves into the possibilities of computer modeling for manipulator systems within the Matlab program. The analysis is directed towards a two-link manipulator model. Within the framework of kinematic analysis, the paper confronts the solution to the inverse kinematics problem and subsequently navigates through the solution to the direct kinematics problem. The trajectory is modeled by a fifth-degree polynomial during the motion from a known initial position to the specified final position within defined working regions of the manipulator. The work encompasses graphical representation of the results. The manipulator's workspace is also delineated, considering angular constraints on both arms and illustrating the trajectories during operational movement. [ABSTRACT FROM AUTHOR]

The quest to comprehend the nature of consciousness has spurred the development of many theories that seek to explain its underlying mechanisms and account for its neural correlates. In this paper, I compare my own conscious electromagnetic information field (cemi field) theory with integrated information theory (IIT) and global workspace theory (GWT) for their ability to 'carve nature at its joints' in the sense of predicting the entities, structures, states and dynamics that are conventionally recognized as being conscious or nonconscious. I go on to argue that, though the cemi field theory shares features of both integrated information theory and global workspace theory, it is more successful at carving nature at its conventionally accepted joints between conscious and nonconscious systems, and is thereby a more successful theory of consciousness. [ABSTRACT FROM AUTHOR]

This research paper outlines the development of a modular and adjustable transfer care robot aimed at enhancing safe and comfortable transfers for individuals with lower limb disabilities. To design this robot, we utilized a 3D motion capture system to analyze the movements of a person assisting another person and to determine the necessary range of motion and workspace for the robot. Based on this analysis, we developed a 3-UPS + UPR parallel spreader to transfer the person receiving care. We also conducted kinematic and dynamic analyses of the parallel spreader to validate its operational space and to obtain the force change curve for the drive. To evaluate the robot's performance, we enlisted the help of ten volunteers with varying heights and weights. Our findings indicate that the pressure distribution during transfers remained largely consistent. Additionally, the surveys revealed that those receiving care perceived the robot as being capable of securely and comfortably transferring individuals between different assistive devices. This modular and adaptable transfer assistance robot presents a promising solution to the challenges encountered in caregiving. [ABSTRACT FROM AUTHOR]

A novel 5-DOF (5-SPS)+5R2U hybrid redundantly driven mechanism (HRDM for short) is proposed, which can realize 3 translations and 2 rotations (3T2R) movements. (5-SPS)+5R2U parallel mechanism is composed of six driving limbs. Of which 5-SPS (S represents spherical pair, P represents prismatic pair) limbs are symmetrically distributed at the center point of static and moving platform have no restriction on the degrees of freedom of the mechanism. The middle limb (7R)U (R represents revolute pair, U represents Hooke joint) is connected to the static platform and the center point of the moving platform. It is jointly driven by constant velocity motor and servo motor, and plays a role of restraining the freedom of the whole mechanism. It is called hybrid redundantly driven limb (HRDL for short). Hybrid-driven mechanism and redundantly actuated mechanism can be integrated into one mechanism by HRDL, which can give full play to the advantages of both. The inverse position solution model of the mechanism is established, and the velocity Jacobian matrix and acceleration expression are derived to obtain the velocity and acceleration variation laws of the mechanism. On this basis, the factors affecting the workspace are analyzed, and the workspace atlas under different orientation angles is obtained. The results provide theoretical model for the realization planning trajectory of (5-SPS)+5R2U HRDM. [ABSTRACT FROM AUTHOR]

The quality of indoor lighting significantly influences human well-being, emphasizing the need to integrate lighting planning into the architectural design process. To optimize indoor lighting conditions, light environment simulations are commonly employed. While much of the relevant literature clearly shows that simulations are widely used to predict lighting environments, there is limited active research validating these simulations. Therefore, this study aimed to assess the alignment between actual measurements and simulations, specifically focusing on daylight-induced glare. To achieve this, a comparative analysis and verification of glare levels between simulations and actual measurements were conducted that accounted for glare location and direction. Disparities between the simulated and measured glare levels were revealed contingent on the glare location and direction. These variations primarily arose from the simulation's utilization of a fisheye field of view (FOV) for glare measurement. To improve the accuracy of glare analysis in simulations, it is advisable to follow the standards related to the human perception of glare, such as the human field of view (FOV), instead of solely depending on a fisheye FOV. The study's limitations include challenges in environmental replication, minor measurement errors, and tree branch shading interference. Despite the potential for simulations to not replicate temporary glare effects, consistent differences with actual measurements indicate that the fisheye FOV was a key contributing factor. [ABSTRACT FROM AUTHOR]

In recent years, virtual microgravity training technology for astronauts based on cable-driven designs has emerged, and it solves the following problems: high costs, short training times, and low safety of existing equipment. However, this technology does not solve the reduced motion accuracy problem of the operated object due to the elastic deformation of cables, and this problem will reduce the operational experience of astronauts during training. In view of this problem, a cable-driven virtual operation training system for astronauts is designed, and a new composite control strategy based on parallel cables is proposed, which effectively improves motion control accuracy by allocating cable tension and using a tension compliance control method to suppress the influence of cable deformation. In addition, the desired tension of cables is optimized based on the system's workspace so that the system can achieve more complex virtual microgravity training tasks. Finally, verification via experiments demonstrated that the training system and the new composite control strategy are effective. [ABSTRACT FROM AUTHOR]

3-XXRRU parallel manipulators (PMs) constitute a family of six-degrees-of-freedom (DOF) PMs with three limbs of type XXRRU, where R and U stand for revolute pair and universal joint, respectively, and XX indicates any actuated two-DOF mechanism that moves the axis of the first R-pair. The members of this family share the fact that they all become particular 3-RRU structures when the actuators are locked. By exploiting this feature, the present paper proposes a general approach, which holds for all the members of this family, to analyze the instantaneous kinematics, workspace, and kinetostatic performances of any 3-XXRRU PM. The results of this study include the identification of singularity conditions without reference to a specific actuation system, the proposal of two specific dimensionless performance indices ranging from 0 to 1, the determination of the optimal actuation system, and the demonstration that 3-XXRRU PMs, when appropriately sized and actuated, possess a broad singularity-free workspace that is also fully isotropic. These findings hold significance in the context of the dimensional synthesis and control of 3-XXRRU PMs. Moreover, when combined with the closed-form solutions for their positional analysis, as demonstrated in a previous publication by the same authors, 3-XXRRU PMs emerge as intriguing alternatives to other six-DOF PMs. The efficacy of the proposed approach is further illustrated through a case study. [ABSTRACT FROM AUTHOR]

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Copyright of Egyptian Journal of Information Sciences is the property of Beni Suef University 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.)

Based on the topology design theory and method of parallel mechanism of position and orientation characteristic (POC) theory, a new 3-DOF parallel mechanism with cylindrical translation and one rotation (2T1R) is designed, and the topological characteristics of the mechanism are analyzed, including the calculation of the position and orientation characteristic set, degrees of freedom and coupling degrees; then the kinematics of the mechanism is analyzed, the forward and inverse solutions of the position of the mechanism are solved and verified; finally, based on the forward and inverse position solutions of the mechanism, the work space and rotation capacity of the mechanism are analyzed. The work of this research lays a foundation for the subsequent scale optimization, error analysis and dynamic analysis of the mechanism.