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Internal gearings are commonly used in transmissions due to their advantages like high-power density. To ensure high efficiency, load-carrying capacity and good noise behavior, a profound knowledge of the local gear mesh is essential. The tooth contact of internal gears relates to a convex and concave surface that form a conformal contact. This is in contrast to external gears, where two convex surfaces form a contraformal contact. This paper aims at a better understanding of conformal contacts under elastohydrodynamic lubrication (EHL) to improve the design of internal gearings.

An existing numerical EHL model is used for studying the characteristic properties of a hard conformal EHL line contact. A hard contraformal EHL line contact is studied as reference. Non-Newtonian fluid behavior and thermal effects are considered. By taking into account the local contact conformity and kinematics, the effects and relevance of the curvature of the lubricant gap and micro-slip are analyzed. In a parameter study, scale effects of the contact radii on film thickness, temperature rise and friction are examined.

The curvature of the lubricant gap and effects of micro-slip are small in hard conformal EHL line contacts. For high micro-slip, it can be neglected. Hence, the modeling of conformal contacts using an equivalent geometry of the contact problem is reasonable. The parameter study shows beneficial tribological aspects of the conformal contact compared to the contraformal contact. Higher film thickness and lower fluid coefficient of friction are observed for conformal contacts, which can be attributed to lower pressures for the case of the same external normal force, or to a higher contact temperature rise for the case of equivalent contact pressure.

Despite its widespread existence, the local geometry and kinematics in hard conformal EHL line contacts like in internal gearings have been rarely studied. The findings help for a better understanding of local contact characteristics and its relevance. The quantified scale effects help to improve the efficiency and load-carrying capacity of machine elements with hard conformal EHL contacts, like internal gearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2022-0366/

Environmental social work (ESW) is an approach and a perspective in social work focusing on ecological and environmental sustainability and justice within the context of sustainable development (SD). This study aims to analyse students’ reflective tasks on challenges for ESW education and practice from a critical theory perspective. The purpose of this study is to discuss the implications of the findings for accelerating the implementation of SD in social work curricula.

The research participants comprised 49 master level students from four different cohorts studying the course “Social Work and Sustainable Development” at the University of Gävle, Sweden. The sample comprised only those students who had completed at least one of the three non-mandatory reflective tasks that were set within the course. The reflective tasks of the research participants were gathered as data for this study. A qualitative methodological approach with the help of ATLAS-ti V8.4 was used to analyse the gathered data.

This study discusses three primary results, which are categorised as “Being Boxed”, “Safe and Saviour Sweden” and “Politics and Power”. Based on the results, this study argues for a transformative and emancipatory pedagogy (TEP) in the teaching and learning of ESW to accelerate the implementation of holistic SD within the social work curriculum.

This study is mainly based on the analysis of “problematic” discourses of some of the students. The majority of the students and their respective discourses are not considered. Moreover, it would have been interesting, and probably enlightening to explore the background of the students (such as gender, ethnicity and religion) and any concomitant beliefs or prejudices (whether consciously held or otherwise) that would need to be addressed for an effective social work outcome. For ethical reasons, the background of the students was not recorded and analysed in this study.

Based on the results, this study argues for TEP in catalysing environmentalism within the social work curricula.

Social workers have a political mandate from their professional ethics to work for the protection of the planet and for the well-being of all – including non-humans. This study therefore argues for ESW education within social work curricula in promoting SD through social work practice.

Within the context of SD, there is a global call for social work education to shift from an anthropocentric to an eco-centric paradigm. However, ESW education is still in its infancy stage and very few universities are focusing in this particular area. This study therefore brings an important and well-needed layer of empirical evidence in considering the implications for catalysing environmentalism within the social work curricula.

This paper describes a two-month summer intensive course designed to introduce participants with a hands-on technical craft on robotics and to acquire experience in the low-level details of embedded systems. Attendants started this course with a brief introduction to robotics; learned to draw, design and create a personalized 3D structure for their mobile robotic platform and developed skills in embedded systems. They were familiarize with the practices used in robotics, learning to connect all sensors and actuator, developing a typical application on differential kinematic using Arduino, exploring ROS features under Raspberry Pi environment and Arduino – Raspberry Pi communication. Different paradigms and some real applications and programming were addressed on the topic of Artificial Intelligence. Throughout the course, participants were introduced to programming languages (including Python and C++), advanced programming concepts such as ROS, basic API development, system concepts such as I2C and UART serial interfaces, PWM motor control and sensor fusion to improve robotic navigation and localization. This paper describes not just the concept, layout and methodology used on RobotCraft 2017 but also presents the participants knowledge background and their overall opinions, leading to focus on lessons learned and suggestions for future editions.