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Article
Publication date: 17 May 2022

Philipp C. Sauer, Minelle E. Silva and Martin C. Schleper

While various supply chain (SC) sustainability investigations exist, their connection to supply chain resilience (SCRes) remains largely unexplored. To fill this gap, the authors…

1809

Abstract

Purpose

While various supply chain (SC) sustainability investigations exist, their connection to supply chain resilience (SCRes) remains largely unexplored. To fill this gap, the authors answer the question: “How do firms' sustainability actions affect their SCs' resilience and sustainability trajectories in turbulent environments?" by exploring the context of the COVID-19 pandemic.

Design/methodology/approach

The authors conducted 10 case studies in five industries located in six European countries. A total of 19 semi-structured interviews and relevant secondary data were collected and analyzed in reference to SC sustainability learning and the literature on SCRes approaches (i.e. engineering, ecological and social-ecological).

Findings

31 SC actions referring to different sustainability dimensions were identified to map SCRes learning through a temporal, spatial and functional scale analysis. While five cases are related to an engineering approach focused on “bouncing back” to pre-pandemic goals, three cases were focused on “bouncing forward” as part of an ecological approach. Moreover, the authors identified the existence of two social-ecological resilience cases which developed long-term actions, updating functional set-ups transcending the SC level. The results furthermore illustrate an influence of the SCRes approaches on SC sustainability learning, generating three different paths: flat, flat ascending and ascending SC sustainability trajectories.

Research limitations/implications

The study develops an overview of the adoption of SCRes approaches due to temporal, spatial and functional scales, and their effect on SC sustainability trajectories through exploitation and exploration capabilities. Future research should elaborate on potential moderators in the proposed relationships.

Practical implications

A better understanding of the link between SC sustainability actions and SCRes will help practitioners to make better informed decisions in turbulent environments.

Originality/value

Unlike previous research, this paper provides empirical evidence on engineering, ecological and social-ecological SCRes approaches, as well as SC sustainability trajectories.

Details

International Journal of Operations & Production Management, vol. 42 no. 8
Type: Research Article
ISSN: 0144-3577

Keywords

Article
Publication date: 17 June 2021

Zeguo Yang, Mantian Li, Fusheng Zha, Xin Wang, Pengfei Wang and Wei Guo

This paper aims to introduce an imitation learning framework for a wheeled mobile manipulator based on dynamical movement primitives (DMPs). A novel mobile manipulator with the…

Abstract

Purpose

This paper aims to introduce an imitation learning framework for a wheeled mobile manipulator based on dynamical movement primitives (DMPs). A novel mobile manipulator with the capability to learn from demonstration is introduced. Then, this study explains the whole process for a wheeled mobile manipulator to learn a demonstrated task and generalize to new situations. Two visual tracking controllers are designed for recording human demonstrations and monitoring robot operations. The study clarifies how human demonstrations can be learned and generalized to new situations by a wheel mobile manipulator.

Design/methodology/approach

The kinematic model of a mobile manipulator is analyzed. An RGB-D camera is applied to record the demonstration trajectories and observe robot operations. To avoid human demonstration behaviors going out of sight of the camera, a visual tracking controller is designed based on the kinematic model of the mobile manipulator. The demonstration trajectories are then represented by DMPs and learned by the mobile manipulator with corresponding models. Another tracking controller is designed based on the kinematic model of the mobile manipulator to monitor and modify the robot operations.

Findings

To verify the effectiveness of the imitation learning framework, several daily tasks are demonstrated and learned by the mobile manipulator. The results indicate that the presented approach shows good performance for a wheeled mobile manipulator to learn tasks through human demonstrations. The only thing a robot-user needs to do is to provide demonstrations, which highly facilitates the application of mobile manipulators.

Originality/value

The research fulfills the need for a wheeled mobile manipulator to learn tasks via demonstrations instead of manual planning. Similar approaches can be applied to mobile manipulators with different architecture.

Details

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

Keywords

Article
Publication date: 20 March 2017

Abhishek Jha and Shital S. Chiddarwar

This paper aims to present a new learning from demonstration-based trajectory planner that generalizes and extracts relevant features of the desired motion for an industrial robot.

477

Abstract

Purpose

This paper aims to present a new learning from demonstration-based trajectory planner that generalizes and extracts relevant features of the desired motion for an industrial robot.

Design/methodology/approach

The proposed trajectory planner is based on the concept of human arm motion imitation by the robot end-effector. The teleoperation-based real-time control architecture is used for direct and effective imitation learning. Using this architecture, a self-sufficient trajectory planner is designed which has inbuilt mapping strategy and direct learning ability. The proposed approach is also compared with the conventional robot programming approach.

Findings

The developed planner was implemented on the 5 degrees-of-freedom industrial robot SCORBOT ER-4u for an object manipulation task. The experimental results revealed that despite morphological differences, the robot imitated the demonstrated trajectory with more than 90 per cent geometric similarity and 60 per cent of the demonstrations were successfully learned by the robot with good positioning accuracy. The proposed planner shows an upper hand over the existing approach in robustness and operational ease.

Research limitations/implications

The approach assumes that the human demonstrator has the requisite expertise of the task demonstration and robot teleoperation. Moreover, the kinematic capabilities and the workspace conditions of the robot are known a priori.

Practical implications

The real-time implementation of the proposed methodology is possible and can be successfully used for industrial automation with very little knowledge of robot programming. The proposed approach reduces the complexities involved in robot programming by direct learning of the task from the demonstration given by the teacher.

Originality/value

This paper discusses a new framework blended with teleoperation and kinematic considerations of the Cartesian space, as well joint space of human and industrial robot and optimization for the robot programming by demonstration.

Details

Industrial Robot: An International Journal, vol. 44 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 18 January 2024

Sa Xiao, Xuyang Chen, Yuankai Lu, Jinhua Ye and Haibin Wu

Imitation learning is a powerful tool for planning the trajectory of robotic end-effectors in Cartesian space. Present methods can adapt the trajectory to the obstacle; however…

Abstract

Purpose

Imitation learning is a powerful tool for planning the trajectory of robotic end-effectors in Cartesian space. Present methods can adapt the trajectory to the obstacle; however, the solutions may not always satisfy users, whereas it is hard for a nonexpert user to teach the robot to avoid obstacles in time as he/she wishes through demonstrations. This paper aims to address the above problem by proposing an approach that combines human supervision with the kernelized movement primitives (KMP) model.

Design/methodology/approach

This approach first extracts the reference database used to train KMP from demonstrations by using Gaussian mixture model and Gaussian mixture regression. Subsequently, KMP is used to modulate the trajectory of robotic end-effectors in real time based on feedback from its interaction with humans to avoid obstacles, which benefits from a novel reference database update strategy. The user can test different obstacle avoidance trajectories in the current task until a satisfactory solution is found.

Findings

Experiments performed with the KUKA cobot for obstacle avoidance show that this approach can adapt the trajectories of the robotic end-effector to the user’s wishes in real time, including trajectories that the robot has already passed and has not yet passed. Simulation comparisons also show that it exhibits better performance than KMP with the original reference database update strategy.

Originality/value

An interactive learning approach based on KMP is proposed and verified, which not only enables users to plan the trajectory of robotic end-effectors for obstacle avoidance more conveniently and efficiently but also provides an effective idea for accomplishing interactive learning tasks under constraints.

Details

Industrial Robot: the international journal of robotics research and application, vol. 51 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 11 May 2012

Iris Snoeck and Elke Struyf

The aim of this study is to analyse the experiences of student teachers and mentors regarding in‐service teacher‐training or the “Learning in the Workplace Trajectory” (LIW) in…

868

Abstract

Purpose

The aim of this study is to analyse the experiences of student teachers and mentors regarding in‐service teacher‐training or the “Learning in the Workplace Trajectory” (LIW) in Flemish secondary schools. How is this trajectory perceived by mentors and student teachers, i.e. do their individual expectations and capacities match with the formal guidelines implemented by the teacher‐training institutes (and how)?

Design/methodology/approach

This study investigates the LIW trajectory on a pragmatic level, using qualitative research methods such as semi‐structured interviews. The focus of this study is twofold: coaching during the LIW trajectory and evaluation during and at the end of the LIW trajectory.

Findings

The majority of the respondents (mentors and student teachers) indicated that adequate communication and partnership between school and teacher‐training institute (on both organizational and individual level) is essential for a successful trajectory. The challenges which both organizations have to face in order to establish an effective partnership and to effectively guide future student teachers towards their future profession, were made transparent: invest in intensive coaching and install structural involvement of both school and institute during the trajectory.

Research limitations/implications

This study was limited to a qualitative methodology and therefore has very few universal implications. Furthermore, this study originated from a practical point‐of‐view, with no interest in finding new theoretical insights on workplace learning.

Social implications

This study shows that without sufficient financial and structural support from the government, schools and teacher‐training institutes are left facing the challenges (finding ways to invest in and increase coaching the LIW student teachers and structural involvement in the organization of the LIW trajectory of schools) on their own.

Originality/value

This study aimed to highlight the perspective of student teachers and mentors – in other words to see this “Learning in the Workplace Trajectory” through their experience, as they experience(d) it in order to get a look inside the daily practice of both LIW students and mentors during coaching and evaluation.

Details

Journal of Workplace Learning, vol. 24 no. 4
Type: Research Article
ISSN: 1366-5626

Keywords

Article
Publication date: 15 March 2023

Jinzhong Li, Ming Cong, Dong Liu and Yu Du

Under the development trend of intelligent manufacturing, the unstructured environment requires the robot to have a good generalization performance to adapt to the scene changes…

139

Abstract

Purpose

Under the development trend of intelligent manufacturing, the unstructured environment requires the robot to have a good generalization performance to adapt to the scene changes. The purpose of this paper aims to present a learning from demonstration (LfD) method (task parameterized [TP]-dynamic movement primitives [DMP]-GMR) that combines DMPs and TP-LfD to improve generalization performance and solve object manipulation tasks.

Design/methodology/approach

The dynamic time warping algorithm is applied to processing demonstration data to obtain a more standard learning model in the proposed method. The DMPs are used to model the basic trajectory learning model. The Gaussian mixture model is introduced to learn the force term of DMPs and solve the problem of learning from multiple demonstration trajectories. The robot can learn more local geometric features and generalize the learned model to unknown situations by adding task parameters.

Findings

An evaluation criterion based on curve similarity calculated by the Frechet distance was constructed to evaluate the model’s interpolation and extrapolation performance. The model’s generalization performance was assessed on 2D virtual data sets, and first, the results show that the proposed method has better interpolation and extrapolation performance than other methods.

Originality/value

The proposed model was applied to the axle-hole assembly task on real robots, and the robot’s posture in grasping and placing the axle part was taken as the task parameter of the model. The experiment results show that The proposed model is competitive with other models.

Details

Robotic Intelligence and Automation, vol. 43 no. 2
Type: Research Article
ISSN: 2754-6969

Keywords

Article
Publication date: 19 March 2021

Zhenyu Lu and Ning Wang

Dynamic movement primitives (DMPs) is a general robotic skill learning from demonstration method, but it is usually used for single robotic manipulation. For cloud-based robotic…

Abstract

Purpose

Dynamic movement primitives (DMPs) is a general robotic skill learning from demonstration method, but it is usually used for single robotic manipulation. For cloud-based robotic skill learning, the authors consider trajectories/skills changed by the environment, rebuild the DMPs model and propose a new DMPs-based skill learning framework removing the influence of the changing environment.

Design/methodology/approach

The authors proposed methods for two obstacle avoidance scenes: point obstacle and non-point obstacle. For the case with point obstacles, an accelerating term is added to the original DMPs function. The unknown parameters in this term are estimated by interactive identification and fitting step of the forcing function. Then a pure skill despising the influence of obstacles is achieved. Using identified parameters, the skill can be applied to new tasks with obstacles. For the non-point obstacle case, a space matching method is proposed by building a matching function from the universal space without obstacle to the space condensed by obstacles. Then the original trajectory will change along with transformation of the space to get a general trajectory for the new environment.

Findings

The proposed two methods are certified by two experiments, one of which is taken based on Omni joystick to record operator’s manipulation motions. Results show that the learned skills allow robots to execute tasks such as autonomous assembling in a new environment.

Originality/value

This is a new innovation for DMPs-based cloud robotic skill learning from multi-scene tasks and generalizing new skills following the changes of the environment.

Details

Assembly Automation, vol. 41 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 7 September 2012

Maria Gustavsson

The purpose of this paper is to investigate individuals' learning and propensity for changing their job situation during downsizing in a company.

809

Abstract

Purpose

The purpose of this paper is to investigate individuals' learning and propensity for changing their job situation during downsizing in a company.

Design/methodology/approach

A case study was carried out in an industrial company that had undergone major downsizing to adapt to changes in production. Approximately 100 employees retrained at the company's training program and 350 employees received notice to quit their jobs. Data for this study consisted of qualitative interviews with 20 workers who faced different transition situations.

Findings

Three general learning trajectories labeled stayers, leavers and reemployed leavers emerged as a consequence of the downsizing. The stayers were the individuals who remained at the company and later retrained to new jobs. The leavers were the individuals who more or less voluntarily left the company to start a new career. The reemployed leavers were dismissed and left involuntarily but were later reemployed at the company.

Practical implications

In cases of downsizing it is important that the organization meets latent wishes for change and considers differentiated reactions connected to age, length of employment, former education, etc., among workers who face different transition situations.

Originality/value

The results imply that the learning trajectories were shaped through participation, thus learning, in the transition program and workplace activities. Each worker has a specific history of experience that shapes their disposition to learning and in which way they are able to adjust to a new job situation.

Details

Journal of Workplace Learning, vol. 24 no. 7/8
Type: Research Article
ISSN: 1366-5626

Keywords

Article
Publication date: 23 October 2009

Matthew Campbell, Irina Verenikina and Anthony Herrington

The purpose of this paper is to provide a case study of a newcomer to the practice of policing to explore conceptualisations of learning through practice. It aims to position…

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Abstract

Purpose

The purpose of this paper is to provide a case study of a newcomer to the practice of policing to explore conceptualisations of learning through practice. It aims to position learning as the intersections of trajectories of being and becoming within a community of practice. The paper seeks to argue that learners need to be understood with respect to their personal histories and how these interact with the social and cultural dimensions of the workplace.

Design/methodology/approach

This paper is a case study of a new police officer with data collected through a series of interviews and observations over a two‐year period.

Findings

The case study presented demonstrates the relationship between prior experience, personal histories, participation and a sense of belonging in shaping the learning of early‐career police officers. It suggests that in considering newcomers to the workplace it is important to view the process of learning as being influence by these interconnected factors.

Research limitations/implications

This study concludes that the position of the individual in the social learning of a community of practice is an important aspect that needs further exploration. Although the significance of learner identity with communities of practice is acknowledged by Lave and Wenger it remains underdeveloped, and continues to present as an area for further research.

Practical implications

Trajectories of learning for newcomers to the workplace are affected by their previous social and cultural experiences and expertise, the association that they bring from these to the new community and participation in practices of the community. There exists, therefore, a role for managers in shaping the organisation to be supportive of these informal learning experience and, thus, the selection and training of managers should be aligned to these goals.

Originality/value

This paper extends current understandings of learning and development in the policing context as well as contributing to the broader discussion of informal learning in the workplace and understanding of experts and novices within communities of practice.

Details

Journal of Workplace Learning, vol. 21 no. 8
Type: Research Article
ISSN: 1366-5626

Keywords

Article
Publication date: 30 April 2021

Dag Håkon Haneberg and Lise Aaboen

The purpose of the present paper is to explore entrepreneurial learning at the centre of communities of practice.

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Abstract

Purpose

The purpose of the present paper is to explore entrepreneurial learning at the centre of communities of practice.

Design/methodology/approach

Learning perspectives from the community of practice concept are applied to interpret and discuss results from an in-depth empirical investigation using a novel qualitative method, the Zaltman metaphor elicitation technique (ZMET), to study the entrepreneurial learning behaviour of ten coaches in a student venture incubator. The coaches are students with a certain level of entrepreneurial experience. Given their coaching roles and practices, the coaches are considered “community insiders”.

Findings

The findings show how the socially situated entrepreneurial learning of community insiders could be considered an adaptive process following multiple learning trajectories depending on with whom and about what the entrepreneur involves in social relationships.

Practical implications

Policy makers seeking to facilitate communities of practice should enable learning activities for community insiders and organic development in addition to networking events and support for the entire ecosystem in order to enable bridging of communities of practice.

Originality/value

The present paper focuses on the entrepreneurial learning of community insiders using a novel qualitative method, ZMET. The paper empirically demonstrates that community insiders learn through an adaptive process and participation in multiple communities of practice. This is both in interaction with the nascent entrepreneurs whom they coach as well as when interacting with other community insiders.

Details

International Journal of Entrepreneurial Behavior & Research, vol. 28 no. 2
Type: Research Article
ISSN: 1355-2554

Keywords

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