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A retrospective on the robot air hockey challenge : benchmarking robust, reliable, and safe learning techniques for real-world robotics

Machine learning methods have a groundbreaking impact in many application domains, but their application on real robotic platforms is still limited. Despite the many challenges associated with combining machine learning technology with robotics, robot learning remains one of the most promising directions for enhancing the capabilities of robots. When deploying learning-based approaches on real rob

LS-IQ : implicit reward regularization for inverse reinforcement learning

Recent methods for imitation learning directly learn a Q-function using an implicit reward formulation rather than an explicit reward function.However, these methods generally require implicit reward regularization to improve stability and often mistreat absorbing states.Previous works show that a squared norm regularization on the implicit reward function is effective, but do not provide a theore

Robust localization, mapping, and navigation for quadruped robots

Quadruped robots are currently a widespread platform for robotics research, thanks to powerful Reinforcement Learning controllers and the availability of cheap and robust commercial platforms. However, to broaden the adoption of the technology in the real world, we require robust navigation stacks relying only on low-cost sensors such as depth cameras. This paper presents a first step towards a ro

Dimensionality reduction and prioritized exploration for policy search

Black-box policy optimization is a class of reinforcement learning algorithms that explores and updates the policies at the parameter level. This class of algorithms is widely applied in robotics with movement primitives or non-differentiable policies. Furthermore, these approaches are particularly relevant where exploration at the action level could cause actuator damage or other safety issues. H

Regularized deep signed distance fields for reactive motion generation

Autonomous robots should operate in real-world dynamic environments and collaborate with humans in tight spaces. A key component for allowing robots to leave structured lab and manufacturing settings is their ability to evaluate online and real-time collisions with the world around them. Distance-based constraints are fundamental for enabling robots to plan their actions and act safely, protecting

Learning stable vector fields on Lie Groups

Learning robot motions from demonstration requires models able to specify vector fields for the full robot pose when the task is defined in operational space. Recent advances in reactive motion generation have shown that learning adaptive, reactive, smooth, and stable vector fields is possible. However, these approaches define vector fields on a flat Euclidean manifold, while representing vector f

Long-term visitation value for deep exploration in sparse-reward reinforcement learning

Reinforcement learning with sparse rewards is still an open challenge. Classic methods rely on getting feedback via extrinsic rewards to train the agent, and in situations where this occurs very rarely the agent learns slowly or cannot learn at all. Similarly, if the agent receives also rewards that create suboptimal modes of the objective function, it will likely prematurely stop exploring. More

Continuous action reinforcement learning from a mixture of interpretable experts

Reinforcement learning (RL) has demonstrated its ability to solve high dimensional tasks by leveraging non-linear function approximators. However, these successes are mostly achieved by 'black-box' policies in simulated domains. When deploying RL to the real world, several concerns regarding the use of a 'black-box' policy might be raised. In order to make the learned policies more transparent, we

Challenges and Drivers for the Adoption of Improved Solar Drying Technologies in Mango Farming: A Case Study of Smallholder Farmers in Mozambique

Mango production plays a vital role in rural livelihoods in Mozambique, yet post-harvest losses remain high, ranging from 25% to over 50%, due to inadequate preservation methods. Improved solar drying technologies offer a sustainable solution by extending shelf life and enhancing product quality. However, their adoption among smallholder mango farmers remains limited. This study investigates the k

Lignin-Sourced Aromatics for Biodegradable Flexible Copolyesters Mimicking Poly(Butylene Adipate-co-Terephthalate)

Poly(butylene adipate-co-terephthalate) (PBAT) is an important commercial biodegradable flexible copolyester, which is dependent on the fossil-based terephthalates for production. In the present work, two series of PBAT-mimicking copolyesters are synthesized using lignin-sourced aromatic monomers, i.e., methyl 4-(2-hydroxyethoxy) vanillate and methyl 4-(2-hydroxyethoxy) benzoate, aliphatic dimethy

Measuring the semantic priming effect across many languages

Semantic priming has been studied for nearly 50 years across various experimental manipulations and theoretical frameworks. Although previous studies provide insight into the cognitive underpinnings of semantic representations, they have suffered from small sample sizes and a lack of linguistic and cultural diversity. In this Registered Report, we measured the size and the variability of the seman

The role of flexible labour arrangements in the formalization of artisanal and small-scale mining: the case of Rwanda

Over the past fifteen years, Rwanda has made significant progress in formalizing mining rights and the production processes of 3Ts minerals in its artisanal and small-scale mining (ASM) sector. However, labour relations remain largely unregulated. This study analyses ASM activities through the production process observations, document reviews, and interviews with key informants involved in the sec

Lawless but not normless : An explorative study on formal and informal control in Darknet forums

Darknet constitutes a part of the internet with a reputation for allowing deviance and criminality. In short, it is often understood as a place where anything goes. Current research on Darknet tends to focus on illicit cryptomarkets, however in this ongoing doctoral research project, I explore how user posts and behaviors are informally and formally controlled and shaped on Darknet forums. Moreove

Death is not the end. Transforming existing but unfinished structures: The case of Nana’s Hotel - Sefwi Wiawso, Ghana

Transformation projects still tend to focus on buildings that once had life. This thesis aims to work with those that were never brought to it. In today’s world, there are an increasing amount of projects that garner a lot of attention and investment quite quickly. Some of these are taken through to the design stage and into development, only for them to suddenly not be viable. Development quickl