Search results

1 – 10 of 704
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 24 May 2022

Fusheng Liu, Zhihang He, Yue Qiao, Xinxin Liu, Xuelong Li, Wang Wei, Bo Su and Ruina Dang

The purpose of this paper is specifically to provide a more intelligent locomotion planning method for a hexapod robot based on trajectory optimization, which could reduce the…

206

Abstract

Purpose

The purpose of this paper is specifically to provide a more intelligent locomotion planning method for a hexapod robot based on trajectory optimization, which could reduce the complexity of locomotion design, shorten time of design and generate efficient and accurate motion.

Design/methodology/approach

The authors generated locomotion for the hexapod robot based on trajectory optimization method and it just need to specify the high-level motion requirements. Here the authors first transcribed the trajectory optimization problem to a nonlinear programming problem, in which the specified motion requirements and the dynamics with complementarity constraints were defined as the constraints, then a nonlinear solver was used to solve. The leg compliance was taken into consideration and the generated motions were deployed on the hexapod robot prototype to prove the utility of the method and, meanwhile, the influence of different environments was considered.

Findings

The generated motions were deployed on the hexapod robot and the movements were demonstrated very much in line with the planning. The new planning method does not require lots of parameter-tuning work and therefore significantly reduces the cycle for designing a new locomotion.

Originality/value

A locomotion generation method based on trajectory optimization was constructed for a 12-degree of freedom hexapod robot. The variable stiffness compliance of legs was considered to improve the accuracy of locomotion generation. And also, different from some simulation work before, the authors have designed the locomotion in three cases and constructed field tests to demonstrate its utility.

Details

Industrial Robot: the international journal of robotics research and application, vol. 49 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Access Restricted. View access options
Article
Publication date: 15 May 2017

Haojie Zhang, Bo Su and Hong Meng

With the dramatically increasing number of substations, robots are expected to inspect equipment in the power industry. However, a traditional robotic system cannot work stably…

456

Abstract

Purpose

With the dramatically increasing number of substations, robots are expected to inspect equipment in the power industry. However, a traditional robotic system cannot work stably because of the strong electromagnetic field in substation. The purpose of this paper is to present a robust and stable robotic system for inspecting the substation equipment without the involvement of workers.

Design/methodology/approach

The paper presents in detail a robotic system that consists of a monitor center and a robot. With the monitor center, the workers could send inspection tasks and monitor status of the robot timely. Once a fault is detected, the alarm message will flash immediately to remind the workers. The patrol mode of the robot comprises teleoperation, regular inspection, special inspection and a key return mode. The robot only relies on a low-cost magnetic sensor for lateral positioning and radio frequency identification technology for longitudinal positioning when working under patrol mode. At each stop point, the substation equipment can be recognized quickly through accurate matching with the template image stored in the database.

Findings

It is shown that the robot could work efficiently and reliably in power substations. The positioning error is proved to be within 5 mm, compared to that of 20 cm by implementing integrated global positioning system-dead reckoning navigation. Because of the high positioning accuracy, it is much easier to recognize the substation equipment. It is observed that nearly 99 per cent of equipments can be recognized.

Research limitations/implications

The proposed robotic system is tested in a simple substation environment. While the proposed system shows satisfactory positioning results, further studies considering changeable weather condition will focus on improving the equipment recognition rate in such environment, such as rainy, snowy and strong sunlight.

Practical implications

The key contribution of this paper is that it provides a robotic system to inspect substation equipment instead of workers, to improve working efficiency and to reduce manpower cost.

Originality/value

This paper presents a robotic system to inspect substation equipment instead of workers. Four patrol modes are designed to meet the inspection demand. Comparing with the previous robotic systems, this system contributes to higher position accuracy and higher equipment recognition rate.

Details

Industrial Robot: An International Journal, vol. 44 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Access Restricted. View access options
Article
Publication date: 18 May 2021

Zhirui Wang, Yezhuo Li, Bo Su, Lei Jiang, Ziming Zhao and Yan-An Yao

The purpose of this paper is to introduce a tetrahedral mobile robot with only revolute joints (TMRR). By using rotation actuators, the mechanism of the robot gains favorable…

241

Abstract

Purpose

The purpose of this paper is to introduce a tetrahedral mobile robot with only revolute joints (TMRR). By using rotation actuators, the mechanism of the robot gains favorable working space and eliminates the engineering difficulties caused by the multilevel extension compared with liner actuators. Furthermore, the rolling locomotion is improved to reduce displacement error based on dynamics analysis.

Design/methodology/approach

The main body of deforming mechanism with a tetrahedral exterior shape is composed of four vertexes and six RRR chains. The mobile robot can achieve the rolling locomotion and reach any position on the ground by orderly driving the rotation actuators. The global kinematics of the mobile modes are analyzed. Dynamics analysis of the robot falling process is carried out during the rolling locomotion, and the rolling locomotion is improved by reducing the collision impulse along with the moving direction.

Findings

Based on global kinematics analysis of TMRR, the robot can realize the continuous mobility based on rolling gait planning. The main cause of robot displacement error and the corresponding improvement locomotion are gained through dynamic analysis. The results of the theoretical analysis are verified by experiments on a physical prototype.

Originality/value

The work introduced in this paper is a novel exploration of applying the mechanism with only revolute joints to the field of tetrahedral rolling robots. It is also an attempt to use the improved rolling locomotion making this kind of mobile robot more practical. Meanwhile, the reasonable engineering structure of the robot provides feasibility for load carrying.

Details

Industrial Robot: the international journal of robotics research and application, vol. 48 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Access Restricted. View access options
Book part
Publication date: 28 September 2020

Dazhi Zheng, Thomas C. Chiang and Edward Nelling

This chapter examines a multifactor model for stock returns in nine Asian markets (Japan, China, South Korea, Hong Kong, Taiwan, Singapore, Indonesia, Malaysia, and Thailand). The…

Abstract

This chapter examines a multifactor model for stock returns in nine Asian markets (Japan, China, South Korea, Hong Kong, Taiwan, Singapore, Indonesia, Malaysia, and Thailand). The authors develop a model using the market risk premium, size, book-to-market, profitability, investment, momentum, price-to-earnings ratio, and dividend yield factors for each market. The empirical results suggest that this eight-factor model can better explain the variations of stock returns than the original Fama–French three-factor model. Factor-based models using local data outperform those using data from US markets. In addition, the evidence suggests that the eight-factor model can better explain stock returns when the market is under stress.

Access Restricted. View access options
Article
Publication date: 1 April 2008

Charles A. Pierce, Ivan S. Muslin, Chantay M. Dudley and Herman Aguinis

We reviewed U.S. federal and state sexual harassment court cases involving a prior workplace romance between the plaintiff and alleged harasser. Results of our content analysis…

702

Abstract

We reviewed U.S. federal and state sexual harassment court cases involving a prior workplace romance between the plaintiff and alleged harasser. Results of our content analysis show that, unlike employees’ decisions, judges’ decisions can be predicted from legal but not ethically salient extralegal case features. Hence, when compared to prior research, our study reveals the following discrepancy: judges follow a traditional legal model, whereas employees follow an ethical model when making decisions about romance‐harassment cases. Our study also reveals that the mere presence (versus absence) of a prior romance reduces the likelihood of a plaintiff’s success in a harassment case. We discuss implications for management practice and research from the perspective of legal and ethical decision making.

Details

Management Research: Journal of the Iberoamerican Academy of Management, vol. 6 no. 1
Type: Research Article
ISSN: 1536-5433

Keywords

Access Restricted. View access options
Article
Publication date: 1 July 1988

Paul Michell

Interorganisational decision making on creativity appears to have similar characteristics to those of the conventional organisational buying process. The composition of…

373

Abstract

Interorganisational decision making on creativity appears to have similar characteristics to those of the conventional organisational buying process. The composition of decision‐making units correlates closely with the costs and risks involved in decisions on new campaigns, extended campaigns and routine creativity. Decisions are taken at high levels, with chief executive officers active at key periods. Top management involvement is high when perceived outcomes are high in cost, high in risk, and highly visible. Product managers' authority levels appear to reflect their past performance record, the number of decision tiers, and the degree of communications openness.

Details

European Journal of Marketing, vol. 22 no. 7
Type: Research Article
ISSN: 0309-0566

Keywords

Available. Content available
Article
Publication date: 20 September 2011

257

Abstract

Details

Soldering & Surface Mount Technology, vol. 23 no. 4
Type: Research Article
ISSN: 0954-0911

Access Restricted. View access options
Article
Publication date: 1 April 1993

T. Singh, C. Engle and M. Cahay

With the advent of sophisticated growth techniques such as Molecular Beam Epitaxy and Metal Organic Chemical Vapor Deposition, the calculation of the energy boundstates and…

30

Abstract

With the advent of sophisticated growth techniques such as Molecular Beam Epitaxy and Metal Organic Chemical Vapor Deposition, the calculation of the energy boundstates and electron wave‐functions of the one‐electron Schrödinger equation has received a lot of attention over the last decade. With the more recent fabrication of quantum wires and dots, it seems now imperative to extend the boundstates calculation to systems containing only a few electrons. Hereafter, we investigate the effect of electron exchange and Coulomb interactions on the boundstates of a two‐electron system in a square quantum well. The technique is based on a general Alternating Direction Implicit algorithm ( T. Singh and M. Cahay, SPIE Vol. 1675, Quantum Wells and Superlattice Physics IV (1992), p.11) combined with a Fourier spectrum analysis of the two‐particle wavefunction correlation , <ψ(χ1,χ2;0)/ψ(χ1,χ2;τ)> , where χ1, χ2 are the coordinates of the two electrons. The precise location of the energy eigenvalues requires the appropriate use of window functions before calculating the Fourier transform of the correlation function. We also compare our results for the boundstate energies with those obtained using a first order time‐independent perturbation theory.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 12 no. 4
Type: Research Article
ISSN: 0332-1649

Access Restricted. View access options
Article
Publication date: 1 August 1977

ERIC SCHLESINGER

The classical view of management did not bother itself with observing what managers actually do. As set out by Henri Fayol, for instance, it laid down the logical and analytical…

105

Abstract

The classical view of management did not bother itself with observing what managers actually do. As set out by Henri Fayol, for instance, it laid down the logical and analytical view of management as a planning, organising, commanding, coordinating and controlling function. This view fitted in well with the claim to be the inheritors of scientific thinking. It gives a calm, rational and logical view — the well‐ordered, well‐planned and surprise‐free world.

Details

Industrial and Commercial Training, vol. 9 no. 8
Type: Research Article
ISSN: 0019-7858

Access Restricted. View access options
Article
Publication date: 1 March 1998

Robert E. Allen and Margaret A. Lucero

This study empirically examined the antecedents of verbal and physical assaults on managers perpetrated by subordinate employees. A model was presented and hypotheses developed…

161

Abstract

This study empirically examined the antecedents of verbal and physical assaults on managers perpetrated by subordinate employees. A model was presented and hypotheses developed that were tested with data obtained through the content analysis of published arbitration decisions. The findings indicated that such assaults were more likely to be verbal than physical, preceded by aversive treatment, and targeted at managers directly involved in the negative outcomes. Additionally, the severity of the incident varied across the different types of triggering events. Individuals who had been aggressive in the past but had not been disciplined were more likely to subsequently engage in physical than verbal assaults. The implications of these findings for future research and organizational practices were also discussed.

Details

International Journal of Conflict Management, vol. 9 no. 3
Type: Research Article
ISSN: 1044-4068

1 – 10 of 704
Per page
102050