170 accepted papers
We present multipanda_ros2, a novel open-source ROS2 architecture for multi-robot control of Franka Robotics robots. Leveraging ros2_control, this framework provides native ROS 2 interfaces for controlling any number of robots from a single process. Our core contributions address key challenges in r…
Reactive motion generation in unstructured environments remains an open challenge in robotics. Due to the computational complexity of collision-free motion generation, existing methods either generate global trajectories for static scenarios, or employ models that make conservative assumptions about
Robotic manipulation of unfamiliar objects in new environments is challenging due to limited generalisation capabilities. We propose a new skill transfer framework, GIFT (Geometry-Induced Functional Transfer), which enables a robot to transfer complex object manipulation skills and constraints from …
This article presents an impact-aware manipulation framework for logistics, where growing e-commerce demands have increased the need for faster and more flexible package handling solutions. The proposed framework addresses swiftly grabbing and placing objects in depalletizing tasks with dual-arm rob…
Therapist-in-the-loop robotic rehabilitation has shown the promise to enhance rehabilitation outcomes by integrating the strengths of therapists and robotic systems. However, its broader adoption is limited due to insufficient interaction and limited adaptation capability. This article proposes a no…
Non-prehensile object manipulation skills are important for real-world robot interactions, enabling highly dynamic tasks such as balancing a glass on a tray or the controlled sliding of items on a table. Among such tasks, those characterised by high-speed manipulation requirements and general sensit…
Robots have surpassed humans in terms of strength and precision, yet humans retain an unparalleled ability for decision-making in the face of unpredictable disturbances. This article aims to combine the strengths of both entities within a singular task: human motion guidance under strict geometric c
Robotic-assisted minimally invasive surgery (RAMIS) requires accurate enforcement of the remote center of motion (RCM) constraint to ensure safe tool motion through a trocar. Existing virtual RCM controllers are commonly formulated either at the kinematic level or as task-space objectives, which mak…
Gaussian Processes (GPs), as a nonparametric learning method, offer flexible modeling capabilities and calibrated uncertainty quantification for function approximations. Additionally, GPs support online learning by efficiently incorporating new data with polynomial-time computation, making them well
Tactile manipulation is a prominent and growing field where most research focuses on developing generalized manipulation policies. However, tactile execution monitoring - the ability to reliably evaluate manipulation at the skill level - is often overlooked, despite being critical for unsupervised d…
As of today, automating contact-rich industrial manipulation processes, such as insertion, plugging, and screw-driving, is tedious and requires expert knowledge. The processes consist of programmable, common action units, like moving to a pose and establishing contact. However, the user still has to…
This paper tackles the challenges of automating battery removal from small electronic devices, such as heat cost allocators and smoke detectors. The process is critical for mitigating fire hazards caused by lithium batteries in recycling facilities and for supporting a circular economy. We focus on …
Modern manufacturing demands robotic assembly systems with enhanced flexibility and reliability. However, traditional approaches often rely on programming tailored to each product by experts for fixed settings, which are inherently inflexible to product changes and lack the robustness to handle vari…
In this paper, we extend the Unified Force-Impedance Control (UFIC) framework for the whole-body control of service mobile robots subject to non-holonomic constraints. This enables the robot to execute complex service tasks that demand both force and impedance control within its whole body workspace
Optimal path planning aims to determine a sequence of states from a start to a goal while accounting for planning objectives. Popular methods often integrate fixed batch sizes and neglect information on obstacles, which is not problem-specific. This study introduces Adaptively Prolated Trees (APT*),
Robots with intrinsic joint elasticity can perform highly dynamic manoeuvres by leveraging energy storage and release, enabling explosive motions such as throwing. By augmenting elastic robots with clutch mechanisms, link decoupling can be used to fully exploit inertial coupling effects and gravitat
This paper introduces Context Informed Trees (CIT*), a sampling-based motion planning algorithm that enhances exploration efficiency by biasing sampling based on uncertainty estimation from local samples and connectivity information obtained during the search process. CIT* is based on Flexible Infor
In an aging society, the need for rehabilitation treatment is expected to rise. As current healthcare systems have limited capacity and personnel, access to rehabilitation devices usable in households can help address the demand. A lower-limb rehabilitation robot designed for home use must be adapta
Optimal path planning requires finding a series of feasible states from the starting point to the goal to optimize objectives. Popular path planning algorithms, such as Effort Informed Trees (EIT*), employ effort heuristics to guide the search. Effective heuristics are accurate and computationally e
This paper presents a novel approach for robot navigation in environments containing deformable obstacles. By integrating Learning from Demonstration (LfD) with Dynamical Systems (DS), we enable adaptive and efficient navigation in complex environments where obstacles consist of both soft and hard r
Robust perception of the environment is a critical challenge for robots, especially those that use mobile platforms or humanoid forms to perform manipulation tasks. Active vision, leveraging strategic camera movements and adaptive imaging parameters, holds great potential for addressing critical cha
Robot manipulation researchers reference human performance as a goal for their work, however, human data is seldom present in robotics benchmarks. We introduce a real-world benchmark targeting manipulation skills for performing electrical circuit inspection with a multimeter using an Internet-connec
This paper presents GARMI’s successful outdoor demonstration during the Kandahar Ski World Cup, where it performed trophy handovers in sub-zero temperatures. The event highlighted challenges in deploying robots in extreme conditions, including fluctuating temperatures and uneven terrain. GARMI achie
Ensuring the sterility of medical equipment, particularly endoscopes used in environments teeming with diverse pathogens and drug-resistant bacteria, is crucial for safe medical procedures. However, the complexity of endoscope reprocessing, which involves numerous dexterous manual manipulations, pos
Robotic system development must adopt a holistic approach for tactile and dynamic tasks, shifting from the decoupled design of end-effectors and robot manipulators for traditional sequential tasks. Although established metrics exist for traditional tasks, such as pick-and-place, they lack the nuance
Large Language Models (LLMs) have gained popularity in task planning for long-horizon manipulation tasks. To enhance the validity of LLM-generated plans, visual demonstrations and online videos have been widely employed to guide the planning process. However, for manipulation tasks involving subtle
Robotic assembly tasks remain an open challenge due to their long horizon nature and complex part relations. Behavior trees (BTs) are increasingly used in robot task planning for their modularity and flexibility, but creating them manually can be effort-intensive. Large language models (LLMs) have r
In pursuit of effective robot-assisted rehabilitation, it is imperative that the robot facilitates rather than hinders the patient's self-movements in appropriate directions. This essential attribute, termed <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/x
In this work, we model and control a cable-driven, remote-actuated system that includes both friction and compliance in its dynamics. The control objective is to solve a regulation problem using a Model Predictive Controller (MPC). Unlike the flexible-joint robot models, which typically assume frict
Teleoperation with haptic feedback allows users to interact with remote environments while retaining a sense of touch. However, the stability and transparency of these systems are compromised under communication network delay. This paper presents an augmented Model-Mediated Teleoperation with 3D obj
The increasing integration of robots in close human environments necessitates robust safety measures that can adapt to evolving tasks and conditions. Current standards rely on task-specific safety evaluations that are often inflexible, requiring repeated assessments whenever task parameters change.
This paper is about generating motion plans for high degree-of-freedom systems that account for both static and dynamic collisions along the entire body. A particular class of mathematical programs with complementarity constraints become useful in this regard. Optimization-based planners can tackle
In this paper, we propose a closed-loop sensitivity-based approach to enhance the robustness of robotic non-prehensile dynamic manipulation tasks. The proposed method aims at fulfilling the transportation of an object, that is free to move on a tray-shaped robot end-effector, in face of not perfectl
Learning from Demonstration (LfD) techniques enable robots to learn and generalize tasks from user demonstrations, eliminating the need for coding expertise among end-users. One established technique to implement LfD in robots is to encode demonstrations in a stable Dynamical System (DS). However, f
Assembly is a crucial skill for robots in both modern manufacturing and service robotics. However, mastering transferable insertion skills that can handle a variety of high-precision assembly tasks remains a significant challenge. This paper presents a novel framework that utilizes diffusion models
This study presents a comprehensive experimental analysis of Twisted String Actuators (TSA), focused on enhancing contraction modelling accuracy and establishing a baseline for TSA tension and impedance control efficacy. A novel TSA string radius function is introduced, computing effective radii for
Contact estimation and force sensing are fundamental requirements for sensitive manipulation and safe physical human-robot interaction. The robot controllers that enable these functions rely on accurate and precise sensing. The performance of external force estimation is influenced by the design of
Laboratory automation is a key driver for higher efficiency and reproducibility of experiments and measurements in natural science laboratories. One process that is particularly susceptible to both manual errors in the physical handling of labware, faulty data analyses, and incomplete reporting is t
Bidirectional motion planning often reduces planning time compared to its unidirectional counterparts. It requires connecting the forward and reverse search trees to form a continuous path. However, this process could fail and restart the asymmetric bidirectional search due to the limitations of laz
Insertion is an essential skill for robots in both modern manufacturing and services robotics. In our previous study, we proposed an insertion skill framework based on forcedomain wiggle motion. The main limitation of this method lies in the robot’s inability to adjust its behavior according to chan…
A typical manipulation task consists of a manipulator equipped with a gripper to grasp and move an object with constraints on the motion of the hand-held object, which may be due to the nature of the task itself or from object-environment contacts. In this paper, we study the problem of computing jo…
Mobile manipulators (MM) have proven valuable in assisting humans in industrial settings. However, their strict separation from humans in controlled environments limits their effectiveness. Efforts have been made to bridge this gap for physical human-robot interaction (pHRI), leading to the developm…
Applications involving serial manipulators, in both co-manipulation with humans and autonomous operation tasks, require the robot to render high admittance so as to minimize contact forces and maintain stable contacts with high-stiffness surfaces. This can be achieved through admittance control, how
The intersection of robotics and artificial intelligence led to a profound paradigm shift in Robot Learning. Robots have the capacity to replicate human actions and also dynamically adapt, innovate, and excel across a spectrum of tasks. However, the heterogeneity in the deployment of robot platforms…
In this work, an upgraded exoskeleton design is presented with enhanced trajectory tracking and mechanical transparency. Compared to the first version, the design features a 3-DoF actuated shoulder joint and a mechanism to regulate the pretension of Bowden cables. Force/torque sensors are installed…
In robotics and biomechanics, accurately determining joint parameters and computing the corresponding forward and inverse kinematics are critical yet often challenging tasks, especially when dealing with highly individualized and partly unknown systems. This paper unveils a cutting-edge kinematic op…
This study presents the development and validation of an innovative hand exoskeleton designed for the re-habilitation of patients with Complex Regional Pain Syndrome (CRPS), a condition frequently arising post-injury or surgeries. The prototype is tailored for the hand, a region commonly affected by…
Performing human-like motion is crucial for service humanoid robots. Real-time motion retargeting allows clear observation of the robot’s pose and provides instant feedback during human demonstrator actions. This paper presents an optimization-based real-time anthropomorphic motion retargeting frame…
Environmental monitoring via UAVs offers unprecedented aerial observation capabilities. However, the limited flight durations of typical multirotors and the demands on human attention in outdoor missions call for more autonomous solutions. Addressing the specific challenges of precise UAV landings –…
A drawing robot avatar is a robotic system that allows for telepresence-based drawing, enabling users to remotely control a robotic arm and create drawings in real-time from a remote location. The proposed control framework aims to improve bimanual robot telepresence quality by reducing the user wor…
The basis for robotics skill learning is an adequate representation of manipulation tasks based on their physical properties. As manipulation tasks are inherently invariant to the choice of reference frame, an ideal task representation would also exhibit this property. Nevertheless, most robotic lea…
This paper introduces a comprehensive user-guided planning framework designed for robots operating in dynamic, human-centered environments – where the ability to execute sequential tasks flexibly and adaptively is paramount. Our planner enables robots to (i) encode object-centric constraints and use…
This study presents an innovative test rig engineered to explore the kinematic and viscoelastic characteristics of human specimen hands. The rig features eight force-controlled motors linked to muscle tendons, enabling precise stimulation of hand specimens. Hand movements are monitored through an op…
Path planning has long been an important and active research area in robotics. To address challenges in high-dimensional motion planning, this study introduces the Force Direction Informed Trees (FDIT*), a sampling-based planner designed to enhance speed and cost-effectiveness in pathfinding. FDIT*…
The ability of a manipulator to compute a geometry-aware quality index for general tasks with different joint configurations is essential. Such workspace assessment is a well-known and studied field in existing robotics literature, often deployed through embodied structures such as voxelized maps. N
Manipulability analysis is a methodology employed to assess the capacity of an articulated system, at a specific configuration, to produce motion or exert force in diverse directions. The conventional method entails generating a virtual ellipsoid using the system’s configuration and model. Yet, this…
This paper addresses the migration of high-frequency robot controllers to remote computing services, which are connected via a communication channel prone to delays and packet loss. The stability of the networked system is guaranteed by ensuring passivity of each subcomponent in the interconnection,…
In path planning, anytime almost-surely asymptotically optimal planners dominate the benchmark of sampling-based planners. A notable example is Batch Informed Trees (BIT*), where planners iteratively determine paths to batches of vertices within the exploration area. However, utilizing a consistent…
Prosthetic limb abandonment remains an unsolved challenge as amputees consistently reject their devices. Current prosthetic designs often fail to balance human-like performance with acceptable device weight, highlighting the need for optimised designs tailored to modern tasks. This study aims to pro…
Signed Distance Fields are a common surface representation method widely used for both 3D mapping and obstacle avoidance. While the former traditionally uses projective Truncated Signed Distance Fields (TSDF), the latter often requires a complete Euclidean Signed Distance Field (ESDF) representation…
This work focuses on the agile transportation of liquids with robotic manipulators. In contrast to existing methods that are either computationally heavy, system/container specific or dependant on a singularity-prone pendulum model, we present a real-time slosh-free tracking technique. This method s…
This study addresses the absence of an identification framework to quantify a comprehensive dynamic model of human and anthropomorphic tendon-driven fingers, which is necessary to investigate the physiological properties of human fingers and improve the control of robotic hands. First, a generalized…
Industrial robots have increased payload, repeatability, and reach compared to collaborative robots, however, they have a fixed position controller and low intrinsic admittance. This makes realizing safe contact challenging due to large contact force overshoots in contact transitions and contact ins…
Established techniques that enable robots to learn from demonstrations are based on learning a stable dynamical system (DS). To increase the robots’ resilience to perturbations during tasks that involve static obstacle avoidance, we propose incorporating barrier certificates into an optimization pro…
Recent advancements in artificial hand development have primarily concentrated on enhancing adaptive grasping, dexterity, as well as the integration of biomimetic skin. However, few designs have successfully combined lightweight, cost-effective solutions, and tactile sensing along with adaptive gras…
This study addresses the critical need for diverse and comprehensive data focused on human arm joint torques while performing activities of daily living (ADL). Previous studies have often overlooked the influence of objects on joint torques during ADL, resulting in limited datasets for analysis. To
This paper presents a teleoperation framework designed for online learning and adaptation of tactile skills, which provides an intuitive interface without need for physical access to execution robot. The proposed tele-teaching approach utilizes periodical Dynamical Movement Primitives (DMP) and Recu…
The rising demand for customized products necessitates the integration of multiple robotic systems, underscoring the need for advanced production planning and scheduling. This paper introduces an ontology-based, artificial intelligence-enhanced method for dynamic task planning and scheduling, aimed…
Intrinsically elastic robots surpass their rigid counterparts in a range of different characteristics. By temporarily storing potential energy and subsequently converting it to kinetic energy, elastic robots are capable of highly dynamic motions even with limited motor power. However, the time-depen…
Markerless motion capture devices such as the Leap Motion Controller (LMC) have been extensively used for tracking hand, wrist, and forearm positions as an alternative to Marker-based Motion Capture (MMC). However, previous studies have highlighted the subpar performance of LMC in reliably recording…
Time-effective and accurate source localization with mobile robots is crucial in safety-critical scenarios, e.g. leakage detection. This becomes particular challenging in realistic cluttered scenarios, i.e. in the presence of complex current flows or wind. Traditional methods often fall short due to…
This paper investigates the problem of effective tool manipulation for motion planning in complex human-like scenarios. Vector-field-based real-time strategies, although widely used, usually do not account for unwieldy tools or incorporate systematic methods to handle these extra maneuvers needed. I…
Controlling the shape of deformable linear objects using robots and constraints provided by environmental fixtures has diverse industrial applications. In order to establish robust contacts with these fixtures, accurate estimation of the contact state is essential for preventing and rectifying poten…
In the field of Learning from Demonstration (LfD), Dynamical Systems (DSs) have gained significant attention due to their ability to generate real-time motions and reach predefined targets. However, the conventional convergence-centric behavior exhibited by DSs may fall short in safety-critical task…
Integrating humanoid service mobile robots into human environments presents numerous challenges, primarily concerning the safety of interactions between robots and humans. To address these safety concerns, we propose a novel approach that leverages the capabilities of digital twin technology by tail…
Flexible manufacturing lines are required to meet the demand for customized and small batch-size products. Even though state-of-the-art tactile robots may provide the versatility for increased adaptability and flexibility, their potential is yet to be fully exploited. To support robotics deployment…
The ability of robotic fingers to exert force and exhibit motion is vital for achieving dexterity in manipulation tasks. To evaluate dexterous capabilities in terms of both features, i.e., quantifying finger performance that facilitates task planning and design optimization, we introduce the Fingert
Bowden cables serve as essential components in various mechanical systems, facilitating power transmission from remote actuators to specific destinations. The pretension of Bowden cables profoundly influences system performance, notably in terms of friction. This study investigates the effects of ca…
The use of pointed or edged tools or objects is one of the most challenging aspects of today’s application of physical human-robot interaction (pHRI). One reason for this is that the severity of harm caused by such edged or pointed impactors is less well studied than for blunt impactors. Consequentl…
Safety for physical human-robot interaction (pHRI) is a major concern for all application domains. While current standardization for industrial robot applications provide safety constraints that address the onset of pain in blunt impacts, these impact thresholds are difficult to use on edged or poin
Non-prehensile transportation of unstable objects presents a challenging task in robotics. To ensure the success of the transportation, it is necessary to consider both the object’s stability via contact dynamics and the motion constraints of the robot. We propose two novel trajectory planning metho…
Despite recent advancements in torque-controlled tactile robots, integrating them into manufacturing settings remains challenging, particularly in complex environments. Simplifying robotic skill programming for non-experts is crucial for increasing robot deployment in manufacturing. This work propos…
With the increasing demand for new healthcare solutions and technologies, such as those resulting from the COVID-19 crisis, and the growing elderly population, exoskeletons for teleoperation are a promising solution for many future medical applications. In this context, we propose two force- sensiti…
As robots become more and more intelligent, the complexity of the algorithms behind them is increasing. Since these algorithms require high computation power from the onboard robot controller, the weight of the robot and energy consumption increases. A promising solution to tackle this issue is to r…
One can estimate the velocity and acceleration of robot manipulators by utilizing nonlinear observers. This involves combining inertial measurement units (IMUs) with the motor encoders of the robot through a model-based sensor fusion technique. This approach is lightweight, versatile (suitable for a…
To speed up and reduce power consumption per cycle in robotic manipulation, one option is to exploit intentional collisions with the surrounding environment and objects, an approach referred to as impact-aware manipulation. Within this context, this paper focuses on developing an online collision mo
The progressive prevalence of robots in human-suited environments has given rise to a myriad of object manipulation techniques, in which dexterity plays a paramount role. It is well-established that humans exhibit extraordinary dexterity when handling objects. Such dexterity seems to derive from a r
Studying the manipulation of deformable linear objects has significant practical applications in industry, including car manufacturing, textile production, and electronics automation. However, deformable linear object manipulation poses a significant challenge in developing planning and control algo…
This letter presents an adaptive optimal control strategy for developing assist-as-needed robotic rehabilitation. The primary goal is to encourage patient participation and increase the effectiveness of training sessions by minimizing robot intervention while following a predefined path. To achieve
Limited resources and resulting energy crises occurring all over the world highlight the importance of energy efficiency in technological developments such as robotic manipulators. Efficient energy consumption of manipulators is necessary to make them affordable and spread their application in the f
Sophisticated manipulation requires both compliance and accuracy. While tactile robots excel at being compliant, their accuracy is often inadequate for complex manipulation. Contact-rich assembly tasks, such as the insertion and manipulation of objects with small tolerances pose an enormous challeng…
Identifying the inertial parameters of real robotic manipulators is a fundamental step towards realistic modeling and better controller performances, which is crucial for safe human-robot interaction. Our work introduces a novel framework for identifying a generalized set of base inertial parameters…
Natural language is one of the most intuitive ways to express human intent. However, translating instructions and commands towards robotic motion generation and deployment in the real world is far from being an easy task. The challenge of combining a robot's inherent low-level geometric and kinodyna…
Compliance with global guidelines for sustainable and responsible production in modern industry requires a comparative analysis of consumer devices' energy consumption (EC). This also holds true for the newly established generation of lightweight industrial robots (LIRs). To identify potential strat…
Elastic actuation taps into elastic elements' energy storage for dynamic motions beyond rigid actuation. While Series Elastic Actuators (SEA) and Variable Stiffness Actuators (VSA) are highly sophisticated, they do not fully provide control over energy transfer timing. To overcome this problem on th
As robots and humans increasingly share the same workspace, the development of safe motion plans becomes paramount. For real-world applications, nonetheless, it is critical that safety solutions are achieved without compromising performance. The computation of safe, time-efficient trajectories, howe…
Shared-autonomy control strategies in teleoperation combine human decision-making and robot precision to solve complex tasks. In other words, advanced autonomous control algorithms can compensate for imprecise human commands, reduce the mental workload of the user, and enable the execution of tasks…
Tactile sensors are becoming more prevalent in numerous research domains, including robotics, human-robot interaction, and grasping. As the development of customized soft tactile skin for various applications continues to gain momentum, there is an increasing demand for the automation of design and…
One of the most important aspects of autonomous systems is safety. This includes ensuring safe human-robot and safe robot-environment interaction when autonomously performing complex tasks or in collaborative scenarios. Al-though several methods have been introduced to tackle this, most are unsuitab…
Automation in the life science research laboratory is a paradigm that has gained increasing relevance in recent years. Current robotic solutions often have a limited scope, which reduces their acceptance and prevents the realization of complex workflows. The transport and manipulation of laboratory…
The adaption of robotic assembly lines to new products is generally slow and costly, binding the economical usage of a single line to a few products manufactured in masses. An important time factor is the adaption of the assembly robot's gripper fingers to the new product components - since finger d
This paper is about fast slosh-free fluid transportation. Existing approaches are either computationally heavy or only suitable for specific robots and container shapes. We model the end effector as a point mass suspended by a spherical pendulum and study the requirements for slosh-free motion and t…
We present an accessible robot interface for telemanipulation (A-RIFT), which preserves the haptic channel partially in a zero-additional-cost interface by visual substitution of force feedback (VSFF). This work explores a gap in the literature, resulting from the focus on performance improvements i…
Strategies for safe human-robot interaction (HRI), such as the well-established Safe Motion Unit, provide a velocity scaling for biomechanically safe robot motion. In addition, psychologically-based safety approaches are required for trustworthy HRI. Such schemes can be very conservative and robot m…
Compliance in actuation has been exploited to generate highly dynamic maneuvers such as throwing that take advantage of the potential energy stored in joint springs. However, the energy storage and release could not be well-timed yet. On the contrary, for multi-link systems, the natural system dynam…
Reaching human-level performance in tactile manipulation is one of the grand challenges in nowadays robotics research. Over the past decade significant progress in both skill control and learning was made. However, the achievable execution speed still falls behind the human ability, without clearly…
As collaborative robots move closer to human environments, motion generation and reactive planning strategies that allow for elaborate task execution with minimal easy-to-implement guidance whilst coping with changes in the environment is of paramount importance. In this paper, we present a novel ap…
Laboratory automation is a suitable solution to establish higher reproducibility with less manual work and thus higher quality standards in life sciences. To date, mobile robots are capable of performing autonomous pick-and-place tasks in the laboratory, and specialized pipetting machines can be use…
Nowadays, wheeled mobile robots constitute a considerable portion of robots in industrial applications. Generally, regardless of their purpose, these systems are not designed to physically interact with humans, other robots, or the environment. In this study, we present a novel safe autonomous mobil…
The human hand capabilities are paramount for highly dexterous manipulation interactions. Unfortunately, the limitations of current technologies make replicating such capabilities unfeasible. Although several works have focused on directly attempting to create robot hands able to mimic human ones cl
In robotics, many control and planning schemes have been developed to ensure human physical safety in human-robot interaction. The human psychological state and the expectation towards the robot, however, are typically neglected. Even if the robot behaviour is regarded as biomechanically safe, human
Manipulability ellipsoids efficiently capture the human pose and reveal information about the task at hand. Their use in task-dependent robot teaching - particularly their transfer from a teacher to a learner - can advance emulation of human-like motion. Although in recent literature focus is shifte…
Kinesthetic teaching of collaborative robots is applied for intuitive and flexible robot programming by demonstration. This enables non-experts to program such robots on the task-level. Multiple strategies exist to teach velocity- or torque-controlled robots and, thus, the maneuverability among comm…
In physical human-robot interaction (pHRI), safety is a key requirement. As collisions between humans and robots can generally not be avoided, it must be ensured that the human is not harmed. The robot reflected mass, the contact geometry, and the relative velocity between human and robot are the pa…
Teleoperated robots are believed to play an important role for future applications in industry, medicine and other domains. Examples for this are remote assembly and maintenance, surgery, diagnosis or deep-sea and space exploration. Such applications are made possible by state-of-the-art tactile man…
Knowledge of the robot's load inertial parameters is indispensable for accurate and safe operation, especially in collaborative robotics. However, an intuitive method for online inertial payload identification, usable while the robot is executing another online generated task, is still lacking. In t…
There exist robotic tasks such as cumbersome object manipulation for which one arm alone is not sufficient and a team of robots should be employed. For such a multi-manual system, a control policy must be defined to meet the task objective. This letter presents a modular uni-arm control law for a mu
Tactile robots shall be deployed for dynamic task execution in production lines with small batch sizes. Therefore, these robots should have the ability to respond to changing conditions and be easy to (re-)program. Operating under uncertain environments requires unifying subsystems such as robot mot…
In modern highly dynamic robot manipulation, collisions between a robot and objects may be intentionally executed to improve performance. To distinguish between these deliberate contacts and accidental collisions beyond the limit of state-of-the-art human-robot interactions, new sensing approaches a…
In order to transform a robot into an intelligent machine it needs to be enabled to react to unforeseen events (most importantly collisions) during task execution and have a plan on how to continue the task afterwards. This requires a flexible operational framework that allows to define adaptive rea…
We discuss a novel method for estimating task Cartesian position and velocity in robot manipulators. This is done by model-based fusion of inertial measurement units with motor encoders. The model is developed to robustly handle the uncertainties in the trajectory. Thus, not only the approach benefi…
The current crisis surrounding the COVID-19 pandemic demonstrates the amount of responsibility and the workload on our healthcare system and, above all, on the medical staff around the world. In this work, we propose a promising approach to overcome this problem using robot-assisted telediagnostics,
The need for comprehensive telemedicine solutions is becoming increasingly relevant due to challenges associated with the ageing population, the increasing shortage of health-care providers, and, more recently, the global pandemic. Existing solutions primarily focus on, e.g., electronic medical reco…
In physical human-robot interaction (pHRI), robots need to detect and react to intended and unintended contacts in a safe manner. Proprioceptive sensing capabilities and collision detection and identification techniques differ among commercially available robots, which means that also their sensitiv…
Safe and efficient trajectory planning for autonomous robots is becoming increasingly important in both industrial applications and everyday life. The demands on a robot which has to react quickly and precisely to changes in cluttered, unknown and dynamic environments are particularly high. Towards
Similar to human work, robotic tasks sometimes require two hands to be accomplished. This requires coordinated motion planning and control. While fulfilling the task in a coordinated manner is already a big challenge, the task at hand becomes even harder when obstacles are introduced in the environm…
The fast growth of communication technologies such as 5G provides high bandwidth and low latency wireless internet access. This enables both high definition video stream and real-time robot commands transmitted between robots and operators in the context of telepresence and teleoperation. Although t…
The rise of collaborative robotics has offered new opportunities for integrating automation into the factories, allowing robots and humans to work side-by-side. However, this close physical coexistence inevitably brings new constraints for ensuring safe human-robot cooperation. The current paramount
Fast and robust gate perception is of great importance in autonomous drone racing. We propose a convolutional neural network-based gate detector (GateNet1) that concurrently detects gate’s center, distance, and orientation with respect to the drone using only images from a single fish-eye RGB camera…
This letter introduces GARMI, a service robotics platform conceptualized with a focus on assisting elderly at home. GARMI is designed to provide support with household tasks, as an avatar for tactile-enabled communication and as an interface for telemedicine and emergency assistance. Its unique huma
Template models are frequently used to simplify the control dynamics for robot hopping or running. Passive limit cycles can emerge for such systems and be exploited for energy-efficient control. A grand challenge in locomotion is trunk stabilization when the hip is offset from the center of mass (Co…
We transform classical robot inertial parameter identification into an online learning problem by integrating state-of-the-art gradient descent techniques and first-order principles from mechanics and differential geometry. Through this, incremental learning of fully physically feasible inertial pro…
This paper addresses the problem of real-time planning in constrained dual-arm manipulation scenarios. Our proposed coupling leverages manipulability information of the cooperative bimanual task-space to a vector-field based planner by means of a repulsive circulatory field, while geometric primitiv…
Humanoid robots in unknown environments need to be able to quickly react to contacts in order to ensure safety of humans and their own hardware. For showing useful reactions to contacts, the robot needs information about possibly multiple contacts such as their respective contact locations and wrenc…
Like humans or animals, robots with compliant joints are capable of performing explosive or cyclic motions by making systematic use of energy storage and release, and it has been shown that they can outperform their rigid counterparts in terms of peak velocity. For rigid joint robots, there exist we
Improving robot systems via newly-developed sensing devices, control algorithms, or state estimators in order to obtain safe and efficient human-robot interaction as well as tactile manipulation skills requires standardized performance measurement protocols for objective comparison. Common protocols…
While many advancements have been made in the development of template models for describing upright-trunk locomotion, the majority of the effort has been focused on the stance phase. In this paper, we develop a new compact dynamic model as a first step toward a fully unified locomotion template mode…
Haptic feedback in teleoperation of flying robots can enable safe flight in unknown and densely cluttered environments. It is typically part of the robot's control scheme and used to aid navigation and collision avoidance via artificial force fields displayed to the operator. However, to achieve ful…
In this paper, we address the problem of vision-based obstacle avoidance for robotic manipulators. This topic poses challenges for both perception and motion generation. While most work in the field aims at improving one of those aspects, we provide a unified framework for approaching this problem.
In this letter, we introduce a novel regressor-based observer method to adapt an initially erroneous dynamics model of serial manipulators for improving collision detection sensitivity. Specifically, we assume that the robot joint velocity and acceleration can be accurately estimated via our previou
In this paper we apply a multi-level structure to robotic manipulation learning. It consists of a hybrid dynamical system we denote skill and a parameter learning layer that leverages the underlying structure to simplify the problem at hand. For the learning layer we introduce a novel algorithm base
In this letter a novel method for accurate and high-bandwidth real-time monitoring of robot collisions is presented. To the authors' knowledge this is the first time the so called direct method, which is mathematically the simplest and theoretically the ideal one, has been realized at practically re
Ideally, a robot controller should not only be designed to exhibit a given interaction behavior under controlled conditions, but also to be robust to changes e.g. in the environment. Within the paradigm of virtual energy tanks for passivity-based controls, robustness may be provided by setting absol
In this paper we introduce a novel framework for expressing and learning force-sensitive robot manipulation skills. It is based on a formalism that extends our previous work on adaptive impedance control with meta parameter learning and compatible skill specifications. This way the system is also ab…
In this paper we introduce dentronics as a new emerging application domain for collaborative lightweight robots in the dental context backed up by a user survey supporting the clear need. Specifically, we developed a multi-modal interaction framework, applied this framework to a specific dental use-…
In this paper we propose a novel energy-based control scheme for an assist-as-needed rehabilitation strategy, which both adapts the level of support based on patient participation and allows the patient to deviate from the prescribed motion in favor of his/her safety. We build an energy network mode…
Kinematic redundancy enhances the dexterity and flexibility of robot manipulators. By exploiting the redundant degrees of freedom, auxiliary null space tasks can be carried out in addition to the primary task. Such auxiliary tasks are often formulated in terms of a performance or safety criterion th…
This paper deals with the problem of accurately computing and estimating joint velocity and acceleration in robotic manipulators. Generally, it is well known that numerical differentiation of noisy position signals even with significant filtering is no viable solution. This is especially true for co…
In practical robotic applications various types of tools are attached for manipulating objects. Besides adding gravitational load to the robot, which results in larger joint torques, such payloads influence the collision safety characteristics through changing surface curvature properties, reflected…
In this paper the first robot-based prototype of a semi-autonomous upper-limb exoprosthesis is introduced, unifying exoskeletons and prostheses [1]. A central goal of this work is to minimize unnecessary interaction forces on the residual limb by compensating gravity effects via a upper body grounde…
In this letter, we propose a new compliant robotics wrist design concept. The system is tendon driven, pneumatically actuated and impedance controlled. We show simulative and experimental results for orientation-based impedance control, human robot interaction with deflection, and collision as well
Encoding desired motions into dynamic movement primitives (DMPs) is a common way for generating compact task representations that are able to handle sensor-based goal adaptations. At the same time, a robot should not only express adaptive motion capabilities at planning level, but use also contact w…
Close physical human-robot interaction makes it essential to ensure human safety. In particular, the intrinsic safety characteristics of a robot in terms of potential human injury have to be understood well. Then, minimal potential harm can be made a key requirement already at an early stage of the
In this paper we introduce a novel point-to-point trajectory planner for serial robotic structures that combines the ability to avoid self-collisions and to respect motion constraints, while complying with the requirement of being C4 continuous. The latter property makes our approach also suited for…
Performing skillfull manipulation is a very challenging task for robots. So far, even experts could barely program them to e.g. perform the well known peg-in-hole problem in the real world. Autonomously acquiring such skills, let alone generalizing them to new tasks, is still a major challenge. Typi…
In this letter, we propose a framework for task allocation in human-robot collaborative assembly planning. Our framework distinguishes between two main layers of abstraction and allocation. In the higher layer, we use an abstract world model, incorporating a multiagent human-robot team approach in o
In this letter, we introduce the concept of an artificial Robot Nervous System (aRNS) as a novel way of unifying multimodal physical stimuli sensation with robot pain-reflex movements. We focus on the formalization of robot pain, based on insights from human pain research, as an interpretation of ta
High-performance collision handling, which is divided into the five phases detection, isolation, estimation, classification and reaction, is a fundamental robot capability for safe and sensitive operation/interaction in unknown environments. For complex humanoid robots collision handling is obviousl…
Ensuring safety is a primary goal in physical human-robot interaction. In various collision experiments it was found that the robot's effective mass, velocity, and geometry are the key parameters which influence the human injury severity during an impact. Recently, a velocity controller was proposed…
Kinematic redundancy is a characteristic and beneficial property in collaborative robots nowadays as it enhances the flexibility and dexterity of the system. While the robot is manipulating an object, it is often necessary to kinematically reconfigure the robot, for example, when it obstructs the hu…
In this paper the concept of a unified torque/impedance controller is applied to a pneumatically actuated, antagonistic robot joint. The investigated control algorithm consists of a cascaded structure in which the outer torque/impedance controller commands a desired torque to two cylinder-based forc…
This letter presents a novel joint torque-based impedance controller for antagonistically driven flexible joints actuated by pneumatic cylinders and compares it with the current state of the art. The work targets on transferring soft-robotics control concepts from classical motor-gear-torque sensor
Soft robotics methods such as impedance control and reflexive collision handling have proven to be a valuable tool to robots acting in partially unknown and potentially unstructured environments. Mainly, the schemes were developed with focus on classical electromechanically driven, torque controlled…
We consider the problem of estimating the wind velocity perceived by a flying multicopter, from data acquired by onboard sensors and knowledge of its aerodynamics model only. We employ two complementary methods. The first is based on the estimation of the external wrench (force and torque) due to ae…
It has recently been shown that intrinsically elastic robots are capable of outperforming rigid robots in terms of peak velocity by making systematic use of energy storage and release. Certainly, high link side velocities are beneficial for performance, however, they also increase the probability of…
Many future application scenarios of robotics envision robotic agents to be in close physical interaction with humans: On the factory floor, robotic agents shall support their human co-workers with the dull and health threatening parts of their jobs. In their homes, robotic agents shall enable peopl…
In this paper, we extend our previous external wrench estimation scheme for flying robots with an aerodynamic model such that we are able to simultaneously estimate aerodynamic and contact forces online. This information can be used to identify the metric wind velocity vector via model inversion. No…
In this paper we propose a novel hybrid Cartesian force/impedance controller that is equipped with energy tanks to preserve passivity. Our approach overcomes the problems of (hybrid) force control, impedance control, and set-point based indirect force control. It allows accurate force tracking, full…
Detecting and interpreting contacts is a crucial aspect of physical Human-Robot Interaction. In order to discriminate between intended and unintended contact types, we derive a set of linear and non-linear features based on physical contact model insights and from observing real impact data that may…