Ding-jian Huang, Li-gang Yao, Wen-jian Li and Jun Zhang
The purpose of this research is to achieve a novel magnetic nutation drive for an industry robotic wrist reducer.
Abstract
Purpose
The purpose of this research is to achieve a novel magnetic nutation drive for an industry robotic wrist reducer.
Design/methodology/approach
A novel magnetic nutation drive is proposed, and the structure and principle of the designed magnetic nutation drive are described in this study. Three-dimensional finite element analysis is used to compute the magnetic and torque of the magnetic nutation drive. Furthermore, a prototype of this novel magnetic nutation drive device is developed with 3D printing technology and tested to verify the feasibility of the proposed structure and principle.
Findings
The simulation and experimental results indicated that the proposed magnetic nutation drive device could meet the desired specifications, and that this novel magnetic nutation drive device successfully realized the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.
Practical implications
This novel magnetic nutation drive is low-cost and easy to make and use, and which provides the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.
Originality/value
For the first time, this research applies the permanent magnet drive technology to nutation drive and puts forward a new non-contact nutation drive mode. The novel drive mode can solve some problems of the traditional mechanical contact nutation drive, such as vibration, friction loss, mechanical fatigue and necessity of lubrication. The proposed non-contact nutation drive device can achieve a high reduction ratio with compact structure and can be suitable for industry application.
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Li Liu, ChengYang Zhou, Xiao Pei, LiZhu Guo, JiaHuan Li, RuiXin Wu and Ding Huang
The purpose of this study is to examine the effects of nitrogen (N) deposition on clonal growth in a rhizome clonal plant, Leymus chinensis (Trin.) Tzvel.
Abstract
Purpose
The purpose of this study is to examine the effects of nitrogen (N) deposition on clonal growth in a rhizome clonal plant, Leymus chinensis (Trin.) Tzvel.
Design/methodology/approach
The study established seven N concentration gradients (0, 2, 4, 8, 16, 32 and 64 g N m−2) to simulate the continuous increase in N deposition for the cultivation of L. chinensis seedlings and assess the response mechanism of the cloned L. chinensis plant at different N levels by analyzing the aboveground and belowground plant appearance traits, parent ramets and daughter ramets of resource allocation and biomass allocation.
Findings
The results of this study showed that the different N treatment levels could promote clonal growth and had certain regularity under the seven treatments. The addition of N could significantly increase the ramet number, rhizome length, rhizome spacer length, biomass of mother ramets, daughter ramets and belowground L. chinensis population when the N addition was greater than 4 g m−2; however, the clonal growth ability of L. chinensis decreased and the rhizome length, ramet number, stem and leaf biomass of daughter ramets and stem biomass of mother ramets significantly decreased when the N addition was greater than 32 g N m−2.
Originality/value
With global warming, atmospheric N deposition is increasing and it is of great significance to explore the response mechanism of different N levels for the growth of clone plants. This study provides basic data and a theoretical basis for the survival prediction of cloned plants under the background of a global climate change strategy and has important theoretical and practical significance for the scientific management of grasslands in the future.
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Chetan Jalendra, B.K. Rout and Amol Marathe
Industrial robots are extensively used in the robotic assembly of rigid objects, whereas the assembly of flexible objects using the same robot becomes cumbersome and challenging…
Abstract
Purpose
Industrial robots are extensively used in the robotic assembly of rigid objects, whereas the assembly of flexible objects using the same robot becomes cumbersome and challenging due to transient disturbance. The transient disturbance causes vibration in the flexible object during robotic manipulation and assembly. This is an important problem as the quick suppression of undesired vibrations reduces the cycle time and increases the efficiency of the assembly process. Thus, this study aims to propose a contactless robot vision-based real-time active vibration suppression approach to handle such a scenario.
Design/methodology/approach
A robot-assisted camera calibration method is developed to determine the extrinsic camera parameters with respect to the robot position. Thereafter, an innovative robot vision method is proposed to identify a flexible beam grasped by the robot gripper using a virtual marker and obtain the dimension, tip deflection as well as velocity of the same. To model the dynamic behaviour of the flexible beam, finite element method (FEM) is used. The measured dimensions, tip deflection and velocity of a flexible beam are fed to the FEM model to predict the maximum deflection. The difference between the maximum deflection and static deflection of the beam is used to compute the maximum error. Subsequently, the maximum error is used in the proposed predictive maximum error-based second-stage controller to send the control signal for vibration suppression. The control signal in form of trajectory is communicated to the industrial robot controller that accommodates various types of delays present in the system.
Findings
The effectiveness and robustness of the proposed controller have been validated using simulation and experimental implementation on an Asea Brown Boveri make IRB 1410 industrial robot with a standard low frame rate camera sensor. In this experiment, two metallic flexible beams of different dimensions with the same material properties have been considered. The robot vision method measures the dimension within an acceptable error limit i.e. ±3%. The controller can suppress vibration amplitude up to approximately 97% in an average time of 4.2 s and reduces the stability time up to approximately 93% while comparing with control and without control suppression time. The vibration suppression performance is also compared with the results of classical control method and some recent results available in literature.
Originality/value
The important contributions of the current work are the following: an innovative robot-assisted camera calibration method is proposed to determine the extrinsic camera parameters that eliminate the need for any reference such as a checkerboard, robotic assembly, vibration suppression, second-stage controller, camera calibration, flexible beam and robot vision; an approach for robot vision method is developed to identify the object using a virtual marker and measure its dimension grasped by the robot gripper accommodating perspective view; the developed robot vision-based controller works along with FEM model of the flexible beam to predict the tip position and helps in handling different dimensions and material types; an approach has been proposed to handle different types of delays that are part of implementation for effective suppression of vibration; proposed method uses a low frame rate and low-cost camera for the second-stage controller and the controller does not interfere with the internal controller of the industrial robot.
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Yi Qing, Moyu Chen, Yu Sheng and Jikun Huang
The purpose of this paper is to investigate the impact of mechanization services on farm productivity in Northern China from an empirical perspective, with the aim to identify the…
Abstract
Purpose
The purpose of this paper is to investigate the impact of mechanization services on farm productivity in Northern China from an empirical perspective, with the aim to identify the underlying market and institutional barriers.
Design/methodology/approach
The authors apply the regression method with the control of village fixed effects to examining the relationship between capital–labor ratio, mechanization service ratio and farm productivity, using the panel data collected in 2013 and 2015 by CCAP.
Findings
Mechanization services improve farm productivity through substituting labor, but it may generate a less positive impact on farms who do not have self-owned capital equipment.
Originality/value
It is the first study to investigate how mechanization services affect farm productivity for grain producers in Northern China.
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Tongwei Qiu, Qinying He, S.T. Boris Choy, Yifei Li and Biliang Luo
This study investigates the effect of renting in land on farm productivity, and the impacts of rented-in land size and transaction partner type on farm productivity.
Abstract
Purpose
This study investigates the effect of renting in land on farm productivity, and the impacts of rented-in land size and transaction partner type on farm productivity.
Design/methodology/approach
Data from the 2015 China Household Finance Survey are analyzed using an extended regression model and the two-stage least squares method.
Findings
Farm households that rent in land are likely to achieve higher farm productivity, and ignoring endogeneity underestimates the positive effect of land renting-in. Further evidence indicates that rented-in land size has an insignificant impact on farm productivity, and that there is no difference in farm productivity between lessees renting-in land from acquaintances and those renting-in land from non-acquaintances. These results may be caused by the higher degree of marketization of land rentals between acquaintances in China. With increasing competition in agricultural factor markets, in theory, rented-in land size should not affect farm productivity.
Practical implications
Overall, the analysis suggests that renting in land improves farm productivity, which supports the land transfer policies that have been rolled out in recent decades in China. However, our finding that rented land size does not affect farm productivity, consistent with the results in the literature, implies that the Chinese government should no longer subsidize or prefer large farms with low productivity. More attention should be paid to small lessees and market-oriented land rentals between acquaintances. Promoting the marketization of land transfers inside acquaintance networks could realize the potential of the land market, especially if land transfers decrease.
Originality/value
This study identifies the effects of renting in land, rented-in land size and type of rental transaction partner on farm productivity using nationally representative data. The findings imply that the government should pay more attention to the marketization of land rentals between acquaintances. Although existing studies regard land rental between acquaintances as informal and of low efficiency, the recent evidence shows that China's land markets are changing, and policy makers should adjust their policies accordingly.
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Maria Alebaki, Maria Psimouli and Stella Kladou
Wine tourism literature still falls behind other streams of research in its ability to assess phenomena associated with the implementation of digital practices to address…
Abstract
Wine tourism literature still falls behind other streams of research in its ability to assess phenomena associated with the implementation of digital practices to address strategic challenges. Moreover, studies on social media in tourism and hospitality prioritize the relationship between tourists’ behavioural aspects and technology. Relationships, experiences and timely responses on the digital environment are particularly important, taken the ‘new normal’ which COVID-19 necessitates. Within this framework, the present case study explores the role of social media (Facebook in specific) in the effort of Cretan wineries to respond to new encounters, as well as the importance, if any, of collaborative practices for developing online strategies of individual businesses. Findings help us identify (a) the role of the winescape studies in exploring the digital environment and (b) the main communication priorities of wineries as expressed through social media during the pandemic crisis.
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Chetan Jalendra, B.K. Rout and Amol Marathe
Industrial robots are extensively deployed to perform repetitive and simple tasks at high speed to reduce production time and improve productivity. In most cases, a compliant…
Abstract
Purpose
Industrial robots are extensively deployed to perform repetitive and simple tasks at high speed to reduce production time and improve productivity. In most cases, a compliant gripper is used for assembly tasks such as peg-in-hole assembly. A compliant mechanism in the gripper introduces flexibility that may cause oscillation in the grasped object. Such a flexible gripper–object system can be considered as an under-actuated object held by the gripper and the oscillations can be attributed to transient disturbance of the robot itself. The commercially available robots do not have a control mechanism to reduce such induced vibration. Thus, this paper aims to propose a contactless vision-based approach for vibration suppression which uses a predictive vibrational amplitude error-based second-stage controller.
Design/methodology/approach
The proposed predictive vibrational amplitude error-based second-stage controller is a real-time vibration control strategy that uses predicted error to estimate the second-stage controller output. Based on controller output, input trajectories were estimated for the internal controller of the robot. The control strategy efficiently handles the system delay to execute the control input trajectories when the oscillating object is at an extreme position.
Findings
The present controller works along with the internal controller of the robot without any interruption to suppress the residual vibration of the object. To demonstrate the robustness of the proposed controller, experimental implementation on Asea Brown Boveri make industrial robot (IRB) 1410 robot with a low frame rate camera has been carried out. In this experiment, two objects have been considered that have a low (<2.38 Hz) and high (>2.38 Hz) natural frequency. The proposed controller can suppress 95% of vibration amplitude in less than 3 s and reduce the stability time by 90% for a peg-in-hole assembly task.
Originality/value
The present vibration control strategy uses a camera with a low frame rate (25 fps) and the delays are handled intelligently to favour suppression of high-frequency vibration. The mathematical model and the second-stage controller implemented suppress vibration without modifying the robot dynamical model and the internal controller.
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Xiaohong Chen, Qi Shi, Zhifang Zhou and Xu Cheng
Digital transformation misalignment refers to disparities in digital transformation levels between suppliers and buyers across the production and operation process. It has…
Abstract
Purpose
Digital transformation misalignment refers to disparities in digital transformation levels between suppliers and buyers across the production and operation process. It has negatively affected supply chain stability. However, the existing research concerning the economic consequences has not been adequately addressed. Therefore, this paper aims to investigate whether such digital transformation misalignment increases supplier financial risk and to identify the factors influencing this relationship.
Design/methodology/approach
This paper examines binary combinations of suppliers and buyers listed on China’s A-share market between 2011 and 2021. This group constitutes a sample to empirically test the influence of digital transformation misalignment on the supplier’s financial risk, as well as the moderating effect of the geographical and organizational distances.
Findings
The paper’s findings demonstrate that digital transformation misalignment has indeed a significant increase in the supplier’s financial risk. Moreover, the impact is more intense when the geographical or organizational distance between the supplier and the buyer is relatively large.
Originality/value
The existing literature rarely explores the potential risks arising from digital transformation misalignment between supply chain partners. Therefore, this paper fills a notable gap as it is the first to study the impact of digital transformation misalignment on the supplier’s financial risk and the specific applied mechanisms. The contribution significantly improves the field of corporate digital transformation, particularly, within the context of supply chain management.
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Xuelei Yang, Hangbiao Shang, Weining Li and Hailin Lan
Based on the socio-emotional wealth and agency theories, this study empirically investigates the impact of family ownership and management on green innovation (GI) in family…
Abstract
Purpose
Based on the socio-emotional wealth and agency theories, this study empirically investigates the impact of family ownership and management on green innovation (GI) in family businesses, as well as the moderating effects of institutional environmental support factors, namely, the technological achievement marketisation index and the market-rule-of law index.
Design/methodology/approach
This study empirically tests the hypotheses based on a sample of listed Chinese family companies with A-shares in 14 heavily polluting industries from 2009 to 2019.
Findings
There is a U-shaped relationship between the percentage of family ownership and GI, and an inverted U-shaped relationship between the degree of family management and GI. Additionally, different institutional environmental support factors affect these relationships in different ways. As the technological achievement marketisation index increases, the U-shaped relationship between the percentage of family ownership and GI becomes steeper, while the inverted U-shaped relationship between the degree of family management and GI becomes smoother. The market rule-of-law index weakens the U-shaped relationship between family ownership and GI.
Originality/value
First, the authors enrich the research on the driving factors of GI from the perspective of the most essential heterogeneity of family businesses. This study shows nonlinear and opposite effects of family ownership and management on GI in family firms. Second, this study contributes to the literature on family firm innovation. GI, not considered by researchers, is regarded as an important deficiency in research on innovation in family businesses. Therefore, this study fills that gap. Third, the study expands research on moderating effects in the literature on GI from the perspective of institutional environmental support factors.
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Liang Ma, Xin Zhang and Gaoshan Wang
Enterprise social media (ESM) are frequently used in enterprises for daily operation. Although many researchers have attempted to understand the antecedents and consequences of…
Abstract
Purpose
Enterprise social media (ESM) are frequently used in enterprises for daily operation. Although many researchers have attempted to understand the antecedents and consequences of ESM use, the integrated model, boundary conditions and mechanism of the impact of ESM use on performance are still unclear. This study fill this research gap by adopting a grounded theory approach to study how ESM use affects employee performance.
Design/methodology/approach
Choosing representative cases, the authors collected interview data and analyzed the data using open coding, axial coding and selective coding.
Findings
The results showed four main categories including ESM use, work efficiency, emotional maintenance and work performance, as well as 14 sub-categories. This paper also constructs a model of the impact of ESM use on work performance. In addition, results showed that ESM use affects employees' work performance through work efficiency and emotional maintenance, and frequency of use and individual characteristics may moderate this process.
Originality/value
This study’s results contribute to the existing ESM literature by finding the integrated model, boundary conditions and mechanism of the impact of ESM use on performance. The authors also contributed to the social media literature by finding 14 sub-categories and four main categories including ESM use, work efficiency, emotional maintenance and work performance. The conclusion of this paper provides guidance and reference for the use and management of internal social media in enterprises.