Robotics

19 pages, 19573 KiB

Open AccessArticle

Effects of Haptic Feedback on Precision Peg Insertion Tasks Under Different Visual and Communication Latency Conditions

by Tomonari Tanioka, Hikaru Nagano, Yuichi Tazaki and Yasuyoshi Yokokohji

Robotics 2025, 14(3), 34; https://doi.org/10.3390/robotics14030034 - 17 Mar 2025

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This study investigated the role of haptic feedback in precision peg insertion tasks conducted via teleoperation under varying visual resolution and communication latency conditions. Experiment 1 examined the combined effects of haptic feedback and the visual resolution, revealing that haptic feedback significantly reduces [...] Read more.

This study investigated the role of haptic feedback in precision peg insertion tasks conducted via teleoperation under varying visual resolution and communication latency conditions. Experiment 1 examined the combined effects of haptic feedback and the visual resolution, revealing that haptic feedback significantly reduces the maximum normal force and mental workload, while enhancing subjective operability, particularly in low-visual-resolution conditions. Experiment 2 evaluated the impact of communication latency, showing that the maximum normal force, operability, and mental workload are affected by increased latency. Notably, the maximum normal force is sensitive even to minimal latency (100 ms), whereas the mental workload and operability remain acceptable under lower-latency conditions. These findings underscore the importance of multi-metric evaluations, as different aspects of performance respond differently to latency. Overall, the results demonstrate the critical role of haptic feedback in enhancing task performance and the user experience in teleoperated precision tasks, offering valuable insights for the design and development of more effective and user-friendly teleoperation systems. Full article

(This article belongs to the Special Issue Robot Teleoperation Integrating with Augmented Reality)

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18 pages, 2430 KiB

Open AccessArticle

The Art of Replication: Lifelike Avatars with Personalized Conversational Style

by Michele Nasser, Giuseppe Fulvio Gaglio, Valeria Seidita and Antonio Chella

Robotics 2025, 14(3), 33; https://doi.org/10.3390/robotics14030033 - 13 Mar 2025

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Abstract

This study presents an approach for developing digital avatars replicating individuals’ physical characteristics and communicative style, contributing to research on virtual interactions in the metaverse. The proposed method integrates large language models (LLMs) with 3D avatar creation techniques, using what we call the [...] Read more.

This study presents an approach for developing digital avatars replicating individuals’ physical characteristics and communicative style, contributing to research on virtual interactions in the metaverse. The proposed method integrates large language models (LLMs) with 3D avatar creation techniques, using what we call the Tree of Style (ToS) methodology to generate stylistically consistent and contextually appropriate responses. Linguistic analysis and personalized voice synthesis enhance conversational and auditory realism. The results suggest that ToS offers a practical alternative to fine-tuning for creating stylistically accurate responses while maintaining efficiency. This study outlines potential applications and acknowledges the need for further work on adaptability and ethical considerations. Full article

(This article belongs to the Special Issue Human–AI–Robot Teaming (HART))

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34 pages, 11494 KiB

Open AccessArticle

Enhanced Hybrid Artificial Fish Swarm Algorithm for Three-Dimensional Path Planning Applied to Robotic Systems

by Ilias Chouridis, Gabriel Mansour, Vasileios Papageorgiou, Michel Theodor Mansour and Apostolos Tsagaris

Robotics 2025, 14(3), 32; https://doi.org/10.3390/robotics14030032 - 10 Mar 2025

Viewed by 615

Abstract

Path planning is a vital challenge in robot navigation. In the real world, robots operate in 3D environments with various obstacles and restrictions. An improved artificial fish swarm algorithm (AFSA) is proposed to solve 3D path planning problems in environments with obstacles. The [...] Read more.

Path planning is a vital challenge in robot navigation. In the real world, robots operate in 3D environments with various obstacles and restrictions. An improved artificial fish swarm algorithm (AFSA) is proposed to solve 3D path planning problems in environments with obstacles. The improved AFSA incorporates a 3D model of 24 possible movement points to more realistically simulate real-world robot movement capabilities. Several improvements are adopted, such as methods of simple and advanced 3D elimination. The 3D implementation of an agent’s navigation model, called an “obstacle heatmap”, is also presented. The use of a safety value factor and a total movement point factor in the AFSA’s objective function are introduced. The combination of improved AFSA and a ray-casting algorithm is also presented. Finally, a method called “multiple laser activation” is introduced to overcome both the main disadvantage of the application of AFSAs in path planning and the limitation of the finite number of possible movement points that appear when bio-inspired algorithms are applied to generate the optimal path in a grid environment. The resulting path is applied to real-world challenges with drones, coordinate measuring machines, and industrial robotic arms. Full article

(This article belongs to the Special Issue Localization and 3D Mapping of Intelligent Robotics)

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15 pages, 1832 KiB

Open AccessArticle

Partial Torque Tensor and Its Building Block Representation for Dynamics of Branching Structures Using Computational Graph

by Takashi Kusaka and Takayuki Tanaka

Robotics 2025, 14(3), 31; https://doi.org/10.3390/robotics14030031 - 10 Mar 2025

Viewed by 454

Abstract

The Euler–Lagrange and Newton–Euler methods are typically used to derive equations of motion for serial-link manipulators. We previously proposed a partial Lagrangian method, which is similar to the Lagrangian method, for handling the equations of motion analytically. Moreover, the proposed method can efficiently [...] Read more.

The Euler–Lagrange and Newton–Euler methods are typically used to derive equations of motion for serial-link manipulators. We previously proposed a partial Lagrangian method, which is similar to the Lagrangian method, for handling the equations of motion analytically. Moreover, the proposed method can efficiently handle multi-link analyses, similar to the Newton–Euler method. The partial Lagrangian method organizes the Lagrangian, which is obtained from the link structure, and torque, which is obtained by differential operations, into a table that can be easily handled by both manual calculations and computer analysis. Furthermore, by representing it using a computational graph, it is possible to perform dynamic analysis while maintaining the structure of a system. By observing the intermediate nodes of this computational graph, it is possible to observe how the torque generated at a particular link affects the joint. Organizing the structure with graphs allows us to consider complex systems as a collection of subgraphs, making this method highly compatible with our proposed partial Lagrangian approach. This study shows that the partial torque tensor can be used as an analog of the partial torque table for serial-link systems by interpreting the meaning of the table, i.e., the partial torque, as the interaction between the links in order to simplify the treatment of branching link systems. Due to the use of the partial torque tensor, the dimensions of the tensor correspond one-to-one with the number of branches, allowing the description of any branching system. Furthermore, by using the proposed building block representation, even complex branching systems can be easily designed and analyzed. Full article

(This article belongs to the Section Sensors and Control in Robotics)

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19 pages, 7651 KiB

Open AccessArticle

Autonomous Robot-Driven Chronic Wound 3D Reconstruction and Analysis System

by Damir Filko and Emmanuel Karlo Nyarko

Robotics 2025, 14(3), 30; https://doi.org/10.3390/robotics14030030 - 6 Mar 2025

Cited by 1 | Viewed by 504

Abstract

Chronic wounds require accurate and objective assessment to monitor healing progress and optimize treatment. Traditional contact-based methods for wound measurement are often uncomfortable for patients, impractical for clinicians, and prone to inaccuracies due to the complex shapes of wounds. Advances in computational power [...] Read more.

Chronic wounds require accurate and objective assessment to monitor healing progress and optimize treatment. Traditional contact-based methods for wound measurement are often uncomfortable for patients, impractical for clinicians, and prone to inaccuracies due to the complex shapes of wounds. Advances in computational power and data analysis have enabled non-contact techniques, particularly digital imaging, to play a greater role in wound assessment. However, challenges persist, as chronic wounds can vary greatly in size, shape, and surface geometry, making accurate 3D modeling difficult. Dynamic changes in wound dimensions during treatment and the potential for occluded areas further complicate assessment. Handheld 3D cameras and sensors, while promising, are limited by user experience and the potential for incomplete reconstructions. To address these challenges, this paper introduces a fully automated system for analyzing chronic wounds. The system consists of a robotic arm, an industrial-grade 3D scanner, and advanced algorithms for extracting and analyzing wound features. This complete pipeline improves the robustness and functionality of the system and enables precise 3D wound modeling and comprehensive data extraction. This paper discusses the operational system, highlights its advancements, and evaluates its potential for enhancing wound monitoring and healing outcomes. Full article

(This article belongs to the Special Issue Development of Biomedical Robotics)

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71 pages, 30249 KiB

Open AccessArticle

Dimensional Synthesis of Parallel Robots Using Bilevel Optimization for Design Optimization and Resolution of Functional Redundancy

by Moritz Schappler

Robotics 2025, 14(3), 29; https://doi.org/10.3390/robotics14030029 - 4 Mar 2025

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Abstract

Parallel-kinematic machines or parallel robots have only been established in a few applications where their advantage over serial kinematics due to their high payload capacity, stiffness, or dynamics with their limited workspace-to-installation-space ratio pays out. However, some applications still have not yet been [...] Read more.

Parallel-kinematic machines or parallel robots have only been established in a few applications where their advantage over serial kinematics due to their high payload capacity, stiffness, or dynamics with their limited workspace-to-installation-space ratio pays out. However, some applications still have not yet been sufficiently or satisfactorily automated in which parallel robots could be advantageous. As their performance is much more dependent on their complex dimensioning, an automated design tool—not existing yet—is required to optimize the parameterization of parallel robots for applications. Combined structural and dimensional synthesis considers all principally possible kinematic structures and performs a separate dimensioning for each to obtain the best task-specific structure. However, this makes the method computationally demanding. The proposed computationally efficient approach for dimensional synthesis extends multi-objective particle swarm optimization with hierarchical constraints. A cascaded (bilevel) optimization includes the design optimization of components and the redundancy resolution for tasks with rotational symmetry, like milling. Two case studies for different end-effector degrees of freedom demonstrate the broad applicability of the combined structural and dimensional synthesis for symmetric parallel robots with rigid links and serial-kinematic leg chains. The framework produces many possible task-optimal structures despite numerous constraints and can be applied to other problems as an open-source Matlab toolbox. Full article

(This article belongs to the Special Issue Robotics and Parallel Kinematic Machines)

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22 pages, 1905 KiB

Open AccessArticle

The Design and Manufacturing of Mithra: A Humanoid Robot with Anthropomorphic Attributes and High-Performance Actuators

by Chathura Semasinghe, Drake Taylor and Siavash Rezazadeh

Robotics 2025, 14(3), 28; https://doi.org/10.3390/robotics14030028 - 28 Feb 2025

Viewed by 850

Abstract

While the concept of humanoid robots stems from the goal of replicating human movement, these systems have yet to match the elegance and efficiency of human locomotion. A key reason for this gap is that current humanoid robots differ from humans in their [...] Read more.

While the concept of humanoid robots stems from the goal of replicating human movement, these systems have yet to match the elegance and efficiency of human locomotion. A key reason for this gap is that current humanoid robots differ from humans in their kinematics, dynamics, and actuator properties. This work seeks to close that gap by designing an optimized humanoid robot with characteristics closely resembling those of an average human. For this purpose, we built a detailed framework for the in-depth electromechanical modeling of actuator components. This model was used in the comprehensive optimization of the robot’s actuator system, which was designed as a multi-objective scheme based on the objectives introduced in our previous work. This process helped both in achieving efficient and high-performance actuators and in streamlining the design of the structural parts to have mass and inertia distributions similar to those of humans. The proposed design process was utilized in the design of our humanoid robot, Mithra. Initial test showed that Mithra achieved its design goals in terms of human-like kinematics and dynamics characteristics, together with sufficient actuator strength for tasks such as stair navigation, squatting, and running. Full article

(This article belongs to the Special Issue Legged Robots into the Real World, 2nd Edition)

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41 pages, 2797 KiB

Open AccessSystematic Review

Assessing Safety in Physical Human–Robot Interaction in Industrial Settings: A Systematic Review of Contact Modelling and Impact Measuring Methods

by Samarathunga S. M. B. P. B., Marcello Valori, Giovanni Legnani and Irene Fassi

Robotics 2025, 14(3), 27; https://doi.org/10.3390/robotics14030027 - 28 Feb 2025

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Abstract

As collaborative robots (cobots) increasingly share workspaces with humans, ensuring safe physical human–robot interaction (pHRI) has become paramount. This systematic review addresses safety assessment in pHRI, focussing on the industrial field, with the objective of collecting approaches and practices developed so far for [...] Read more.

As collaborative robots (cobots) increasingly share workspaces with humans, ensuring safe physical human–robot interaction (pHRI) has become paramount. This systematic review addresses safety assessment in pHRI, focussing on the industrial field, with the objective of collecting approaches and practices developed so far for modelling, simulating, and verifying possible collisions in human–robot collaboration (HRC). To this aim, advances in human–robot collision modelling and test-based safety evaluation over the last fifteen years were examined, identifying six main categories: human body modelling, robot modelling, collision modelling, determining safe limits, approaches for evaluating human–robot contact, and biofidelic sensor development. Despite the reported advancements, several persistent challenges were identified, including the over-reliance on simplified quasi-static models, insufficient exploration of transient contact dynamics, and a lack of inclusivity in demographic data for establishing safety thresholds. This analysis also underscores the limitations of the biofidelic sensors currently used and the need for standardised validation protocols for the impact scenarios identified through risk assessment. By providing a comprehensive overview of the topic, this review aims to inspire researchers to address underexplored areas and foster innovation in developing advanced, but suitable, models to simulate human–robot contact and technologies and methodologies for reliable and user-friendly safety validation approaches. Further deepening those topics, even combined with each other, will bring about the twofold effect of easing the implementation while increasing the safety of robotic applications characterised by pHRI. Full article

(This article belongs to the Section Industrial Robots and Automation)

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18 pages, 9301 KiB

Open AccessArticle

Design of a Dual-Function Autonomous Disinfection Robot with Safety Filter-Based Motion Control

by Yuning Cao , Zehao Wu , I-Ming Chen and Qingsong Xu

Robotics 2025, 14(3), 26; https://doi.org/10.3390/robotics14030026 - 27 Feb 2025

Viewed by 595

Abstract

In the post-COVID era, international business and tourism are quickly recovering from the global lockdown, with people and products traveling faster at higher frequency. This boosts the economy while facilitating the spread of pathogens, causing waves of COVID aftershock with new variants like [...] Read more.

In the post-COVID era, international business and tourism are quickly recovering from the global lockdown, with people and products traveling faster at higher frequency. This boosts the economy while facilitating the spread of pathogens, causing waves of COVID aftershock with new variants like Omicron XBB. Hence, continuous disinfection of our living environments becomes our first priority. Autonomous disinfection robots provide an efficient solution to this issue. Compared to human cleaners, disinfection robots are able to operate tirelessly in harsh environments without increasing the risk of cross-infection. In this paper, we propose the design of a new generation of the Smart Cleaner disinfection robot, which is equipped with both an Ultraviolet-C (UVC) light tower and a hydrogen peroxide (HP) aerosol dispenser. The safety of an autonomous disinfection robot has been a persistent problem, especially when they work in complex environments. To tackle this problem, Hamilton–Jacobi (HJ) reachability is adopted to construct a safety filter for motion control, which guarantees that the disinfection path taken by the robot is collision-free without severely compromising the optimality of control actions. The effectiveness of the developed robot has been demonstrated by conducting extensive experimental studies. Full article

(This article belongs to the Section Sensors and Control in Robotics)

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31 pages, 9392 KiB

Open AccessArticle

The Concept of Quantum Teleportation for Remote Control of a Car-like Mobile Robot

by Joslin Numbi, Nadjet Zioui and Mohamed Tadjine

Robotics 2025, 14(3), 25; https://doi.org/10.3390/robotics14030025 - 26 Feb 2025

Viewed by 460

Abstract

We describe a quantum teleportation protocol for exchanging data between a mobile robot and its control station. Because of the high cost of quantum network systems, we use MATLAB software to simulate the teleportation of data. Our simulation models the dynamic motion of [...] Read more.

We describe a quantum teleportation protocol for exchanging data between a mobile robot and its control station. Because of the high cost of quantum network systems, we use MATLAB software to simulate the teleportation of data. Our simulation models the dynamic motion of a car-like mobile robot (CLMR), considering its mass and inertia and the environmental viscosity. Our remote control method accurately reproduces a mathematical model of the CLMR’s real-world motion. The CLMR’s trajectory is represented by differential equations, with the velocity calculated using the Jacobian matrix. The velocity inputs are teleported from the control station to the CLMR, enabling it to move. Nevertheless, physical constraints cause the deviation of the robot’s trajectory from the predicted trajectory. To correct this deviation, the CLMR’s current position is teleported to the control station. Before implementing this protocol, we calculate the quantum teleportation circuit, and we use quantum gates in matrix form to simulate the data teleportation process. The protocol’s accuracy is assessed by comparing the original data and teleported data, and a good match is obtained. This study demonstrates the feasibility of quantum teleportation for remotely controlling real-time robotic systems over long distances and in environments that interfere with classical wireless communication. Full article

(This article belongs to the Special Issue Autonomous Robotics for Exploration)

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28 pages, 4319 KiB

Open AccessArticle

Agentic Workflows for Improving Large Language Model Reasoning in Robotic Object-Centered Planning

by Jesus Moncada-Ramirez, Jose-Luis Matez-Bandera, Javier Gonzalez-Jimenez and Jose-Raul Ruiz-Sarmiento

Robotics 2025, 14(3), 24; https://doi.org/10.3390/robotics14030024 - 24 Feb 2025

Viewed by 926

Abstract

Large Language Models (LLMs) provide cognitive capabilities that enable robots to interpret and reason about their workspace, especially when paired with semantically rich representations like semantic maps. However, these models are prone to generating inaccurate or invented responses, known as hallucinations, that can [...] Read more.

Large Language Models (LLMs) provide cognitive capabilities that enable robots to interpret and reason about their workspace, especially when paired with semantically rich representations like semantic maps. However, these models are prone to generating inaccurate or invented responses, known as hallucinations, that can produce an erratic robotic operation. This can be addressed by employing agentic workflows, structured processes that guide and refine the model’s output to improve response quality. This work formally defines and qualitatively analyzes the impact of three agentic workflows (LLM Ensemble, Self-Reflection, and Multi-Agent Reflection) on enhancing the reasoning capabilities of an LLM guiding a robotic system to perform object-centered planning. In this context, the LLM is provided with a pre-built semantic map of the environment and a query, to which it must respond by determining the most relevant objects for the query. This response can be used in a multitude of downstream tasks. Extensive experiments were carried out employing state-of-the-art LLMs and semantic maps generated from the widely-used datasets ScanNet and SceneNN. The results show that agentic workflows significantly enhance object retrieval performance, especially in scenarios requiring complex reasoning, with improvements averaging up to 10% over the baseline. Full article

(This article belongs to the Special Issue Embodied Intelligence: Physical Human–Robot Interaction)

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32 pages, 10642 KiB

Open AccessArticle

Dynamic Camera Planning for Robot-Integrated Manufacturing Processes Using a UAV

by Marius Boshoff, Bernd Kuhlenkötter and Paul Koslowski

Robotics 2025, 14(3), 23; https://doi.org/10.3390/robotics14030023 - 21 Feb 2025

Viewed by 572

Abstract

The optimal viewpoint for monitoring robotic production processes is crucial for maintenance, inspection, and error handling, especially in large-scale production facilities, as it maximizes visual information. This paper presents a method for dynamic camera planning using an Unmanned Aerial Vehicle (UAV), enabling collision-free [...] Read more.

The optimal viewpoint for monitoring robotic production processes is crucial for maintenance, inspection, and error handling, especially in large-scale production facilities, as it maximizes visual information. This paper presents a method for dynamic camera planning using an Unmanned Aerial Vehicle (UAV), enabling collision-free operation and measurable, high perspective coverage for a user-defined Region of Interest (ROI). Therefore, optimal viewpoints are searched with a greedy search algorithm and a decision for the optimal viewpoint is derived. The method is implemented within a simulation framework in Unity and evaluated in a robotic palletizing application. Results show that the use of a UAV as dynamic camera achieves up to twice the perspective coverage during continuous flight compared to the current capabilities of static cameras. Full article

(This article belongs to the Section Sensors and Control in Robotics)

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14 pages, 2489 KiB

Open AccessArticle

System Layout and Grasp Efficiency Optimization for a Multirobot Waste Sorting System

by Bart Engelen, Sander Teck, Jef R. Peeters and Karel Kellens

Robotics 2025, 14(3), 22; https://doi.org/10.3390/robotics14030022 - 21 Feb 2025

Viewed by 600

Abstract

The transition towards a circular economy, as outlined in the European Union’s Green Deal, requires the development of industries dedicated to recycling and material recovery. Within this context, the recycling of plastic and packaging waste is critical in reducing greenhouse gas emissions. Traditional [...] Read more.

The transition towards a circular economy, as outlined in the European Union’s Green Deal, requires the development of industries dedicated to recycling and material recovery. Within this context, the recycling of plastic and packaging waste is critical in reducing greenhouse gas emissions. Traditional pick-and-place systems encounter significant challenges when applied to heterogeneous waste streams due to the variability in shape, weight, and material properties of the processed materials. To address these challenges, this research proposes a heuristic to optimize the use of multiple gripper systems within a multirobot multigripper sorting setup, with the goal of both maximizing sorting efficiency and recovery rates in PPW recycling. Therefore, the performance of grippers on specific PPW objects, materials and shapes is quantitatively assessed by measuring the grasp efficiency. This grasp efficiency is incorporated into the proposed scheduling heuristic and used to assign the PPW objects to the different available robots, taking into account the position of the object with respect to the robot and the gripper installed on the robot. This heuristic is then evaluated and benchmarked through simulations considering the sorting system design and the waste stream composition based on a real-world portable robotic material recycling facility. The findings demonstrate substantial improvements in picking efficiency of up to 3.6% and pick rates up to 37.5%, underscoring the potential of advanced heuristic algorithms in robotic waste sorting systems. Future work will focus on refining gripper designs and exploring predictive algorithms to further enhance grasp success rates. Full article

(This article belongs to the Section Industrial Robots and Automation)

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Robotics, Volume 14, Issue 3 (March 2025) – 13 articles

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