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1 – 7 of 7Yahao Wang, Yanghong Li, Zhen Li, HaiYang He, Sheng Chen and Erbao Dong
Aiming at the problem of insufficient adaptability of robot motion planners under the diversity of end-effector constraints, this paper proposes Transformation Cross-sampling…
Abstract
Purpose
Aiming at the problem of insufficient adaptability of robot motion planners under the diversity of end-effector constraints, this paper proposes Transformation Cross-sampling Framework (TC-Framework) that enables the planner to adapt to different end-effector constraints.
Design/methodology/approach
This work presents a standard constraint methodology for representing end-effector constraints as a collection of constraint primitives. The constraint primitives are merged sequentially into the planner, and a unified constraint input interface and constraint module are added to the standard sampling-based planner framework. This approach enables the realization of a generic planner framework that avoids the need to build separate planners for different end-effector constraints.
Findings
Simulation tests have demonstrated that the planner based on TC-framework can adapt to various end-effector constraints. Physical experiments have also confirmed that the framework can be used in real robotic systems to perform autonomous operational tasks. The frameworkâs strong compatibility with constraints allows for generalization to other tasks without modifying the scheduler, significantly reducing the difficulty of robot deployment in task-diverse scenarios.
Originality/value
This paper proposes a unified constraint method based on constraint primitives to enhance the sampling-based planner. The planner can now adapt to different end effector constraints by opening up the input interface for constraints. A series of simulation tests were conducted to evaluate the TC-Framework-based planner, which demonstrated its ability to adapt to various end-effector constraints. Tests on a physical experimental system show that the framework allows the robot to perform various operational tasks without requiring modifications to the planner. This enhances the value of robots for applications in fields with diverse tasks.
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Yahao Wang, Zhen Li, Yanghong Li and Erbao Dong
In response to the challenge of reduced efficiency or failure of robot motion planning algorithms when faced with end-effector constraints, this study aims to propose a new…
Abstract
Purpose
In response to the challenge of reduced efficiency or failure of robot motion planning algorithms when faced with end-effector constraints, this study aims to propose a new constraint method to improve the performance of the sampling-based planner.
Design/methodology/approach
In this work, a constraint method (TC method) based on the idea of cross-sampling is proposed. This method uses the tangent space in the workspace to approximate the constrained manifold pattern and projects the entire sampling process into the workspace for constraint correction. This method avoids the need for extensive computational work involving multiple iterations of the Jacobi inverse matrix in the configuration space and retains the sampling properties of the sampling-based algorithm.
Findings
Simulation results demonstrate that the performance of the planner when using the TC method under the end-effector constraint surpasses that of other methods. Physical experiments further confirm that the TC-Planner does not cause excessive constraint errors that might lead to task failure. Moreover, field tests conducted on robots underscore the effectiveness of the TC-Planner, and its excellent performance, thereby advancing the autonomy of robots in power-line connection tasks.
Originality/value
This paper proposes a new constraint method combined with the rapid-exploring random trees algorithm to generate collision-free trajectories that satisfy the constraints for a high-dimensional robotic system under end-effector constraints. In a series of simulation and experimental tests, the planner using the TC method under end-effector constraints efficiently performs. Tests on a power distribution live-line operation robot also show that the TC method can greatly aid the robot in completing operation tasks with end-effector constraints. This helps robots to perform tasks with complex end-effector constraints such as grinding and welding more efficiently and autonomously.
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Jiao Ge, Jiaqi Zhang, Daheng Chen and Tiesheng Dong
The purpose of this paper is to actively calibrate power density to match the application requirements with as small an actuator as possible. So, this paper introduces shape…
Abstract
Purpose
The purpose of this paper is to actively calibrate power density to match the application requirements with as small an actuator as possible. So, this paper introduces shape memory alloy to design variable stiffness elements. Meanwhile, the purpose of this paper is also to solve the problem of not being able to install sensors on shape memory alloy due to volume limitations.
Design/methodology/approach
This paper introduces the design, modeling and control process for a variable stiffness passive ankle exoskeleton, adjusting joint stiffness using shape memory alloy (SMA). This innovative exoskeleton aids the human ankle by adapting the precompression of elastic components by SMA, thereby adjusting the ankle exoskeletonâs integral stiffness. At the same time, this paper constructs a mathematical model of SMA to achieve a dynamic stiffness adjustment function.
Findings
Using SMA as the driving force for stiffness modification in passive exoskeletons introduces several distinct advantages, inclusive of high energy density, programmability, rapid response time and simplified structural design. In the course of experimental validation, this ankle exoskeleton, endowed with variable stiffness, proficiently executed actions like squatting and walking and it can effectively increase the joint stiffness by 0.2 Nm/Deg.
Originality/value
The contribution of this paper is to introduce SMA to adjust the stiffness to actively calibrate power density to match the application requirements. At the same time, this paper constructs a mathematical model of SMA to achieve a dynamic stiffness adjustment function.
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Liu Xiangde, Ma Hao, Zhang Yi and Wang Wei
With the development of technology, the application scenarios of mobile robots are becoming more and more extensive, accompanied by a variety of application scenarios suitable and…
Abstract
Purpose
With the development of technology, the application scenarios of mobile robots are becoming more and more extensive, accompanied by a variety of application scenarios suitable and safe path planning algorithms are indispensable for mobile robots.
Design/methodology/approach
The purpose of this paper to improve the safety performance of your bot during the execution of tasks. The methods are synthesized in three main areas: setting appropriate safety distances based on the actual radius of the robot, turn penalty reduces the number of turns by applying an additional penalty to the number of turns in a heuristic function and path smoothing is used to improve path reliability by reducing the number of right-angle turns.
Findings
A suitable safety distance greatly improves the safety of mobile robots and facilitates their development. Optimization of turns in the path of mobile robots improves the travel efficiency of robots. Enhancing the safety of mobile robots has become a research hotspot for path-planning algorithms.
Originality/value
This paper proposes a path planning scheme for mobile robots with safe distances, which provides readers with a comprehensive and systematic progress of path planning research. It helps readers to get inspiration from enhancing the safety of mobile robots.
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This article adds to the existing literature by identifying persistent sociocultural norms that influence organizational culture as facilitators of gendered microaggressions…
Abstract
Purpose
This article adds to the existing literature by identifying persistent sociocultural norms that influence organizational culture as facilitators of gendered microaggressions experienced by women in the workplace.
Design/methodology/approach
Data were obtained from 25 women employees in the Indian banking and finance sector following an unstructured interview. Grounded theory was utilized to establish that organizational culture, which in turn is reinforced by gender microaggressions, contributes to its prevalence.
Findings
Gender microaggressions manifest in the form of Alienation, Opportunity Denial, Invisible Restrictions and Sexual Innuendos. The relationship between organizational culture and gender microaggressions is cyclical, reinforcing and strengthening each other.
Originality/value
This is the first study on gender microaggressions to be conducted in the banking and finance sector.
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Yanping Liu, Bo Yan and Xiaoxu Chen
This paper studies the optimal decision-making and coordination problem of a dual-channel fresh agricultural product (FAP) supply chain. The purpose is to analyze the impact of…
Abstract
Purpose
This paper studies the optimal decision-making and coordination problem of a dual-channel fresh agricultural product (FAP) supply chain. The purpose is to analyze the impact of information sharing on optimal decisions and propose a coordination mechanism to encourage supply chain members to share information.
Design/methodology/approach
The two-echelon dual-channel FAP supply chain includes a manufacturer and a retailer. By using the Stackelberg game theory and the backward induction method, the optimal decisions are obtained under information symmetry and asymmetry and the coordination contract is designed.
Findings
The results show that supply chain members should comprehensively evaluate the specific situation of product attributes, coefficient of freshness-keeping cost and network operating costs to make decisions. Asymmetric information can exacerbate the deviation of optimal decisions among supply chain members and information sharing is always beneficial to manufacturers but not to retailers. The improved revenue-sharing and cost-sharing contract is an effective coordination mechanism.
Practical implications
The conclusions can provide theoretical guidance for supply chain managers to deal with information asymmetry and improve the competitiveness of the supply chain.
Originality/value
This paper combines the three characteristics that are most closely related to the reality of supply chains, including horizontal and vertical competition of different channels, the perishable characteristics of FAPs and the uncertainty generated by asymmetric demand information.
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Jake Hoskins, Faruk Anıl Konuk and Jane Emma Machin
The growing demand for sustainable consumption motivates retailers to consider including organic private label products in private label assortments to attract and serve health…
Abstract
Purpose
The growing demand for sustainable consumption motivates retailers to consider including organic private label products in private label assortments to attract and serve health and environmentally conscious consumers, while also possibly improving the image of the private label brand as well. This study aims to examine the impact of prioritizing organic private label products in private label assortments on private label share outcomes.
Design/methodology/approach
Theoretical predictions are empirically examined using a comprehensive store panel sales data set covering 50 distinct metropolitan markets in the USA from 2008 to 2011 in the yogurt product category.
Findings
Findings indicate that private label products may provide strategic value for certain retailers, based on a variety of private label assortment, national brand competition and retailer characteristic dimensions.
Research limitations/implications
This research serves as initial empirical evidence on how organic products may influence private label category share. Future research should consider additional product categories and geographic markets and also seek to understand consumer perceptual factors in more detail.
Practical implications
Retail managers can better understand the role that organic products play in private label portfolios.
Originality/value
While much previous work has examined how organic products sell relative to conventional products and a sizable literature has investigated private label brand strategy, little research has explicitly examined the role of organic products within private label assortments.
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