Tamara Lorenz

University of Cincinnati | UC · Department of Psychology

Human motion contains rich contextual information about not only action, but action intention. In two experiments, we investigated whether the multiscale kinematic information that differentiates intentional actions is the same information to which observers attend when asked to observe an actor’s intended movement. To do so, we first recorded an a...

Upper-limb prostheses are subject to high rates of abandonment. Prosthesis abandonment is related to a reduced sense of embodiment, the sense of self-location, agency, and ownership that humans feel in relation to their bodies and body parts. If a prosthesis does not evoke a sense of embodiment, users are less likely to view them as useful and inte...

Feedforward internal model-based control enabled by efference copies of motor commands is the prevailing theoretical account of motor anticipation. Grip force control during object manipulation-a paradigmatic example of motor anticipation-is a key line of evidence for that account. However, the internal model approach has not addressed the computat...

Human behaviour, along with any natural/biological behaviour, has varying degrees of intrinsic ‘noise’ or variability. Many studies have shown that the structure or patterning of this variability is sensitive to changes in task and constraint. Furthermore, two or more humans interacting together often begin to exhibit similar structures of behaviou...

The grip force applied to maintain grasp of a hand-held object has been typically reported as tightly coupled to the load force exerted by the object as it is actively manipulated, occurring proportionally and consistently in-phase with changes in load force. However, continuous grip force-load force coupling breaks down and grip force is instead o...

Interactive or collaborative pick-and-place tasks occur during all kinds of daily activities, for example, when two or more individuals pass plates, glasses, and utensils back and forth between each other when setting a dinner table or loading a dishwasher together. In the near future, participation in these collaborative pick-and-place tasks could...

A recent study (Grover et al. Exp Brain Res 236(10):2531–2544, 2018) found that the grip force applied to maintain grasp of a hand-held object exhibited intermittent coupling to the changing load forces exerted by the object as it was oscillated. In particular, the strength and consistency of grip force response to load force oscillations was tied...

Human motion is highly variable due to the effects of interaction with the environment and the intentionality of movement. Current assistive device control systems struggle to support this variable human motion as they restrict typically uncontrolled degrees of freedom resulting in unnatural, mechanistic and highly repetitive (i.e., artificially in...

Tightly coordinated grip force adaptations in response to changing load forces have been reported as continuous, stable, and proportional to the load force changes. Considering the existence of inherent sensorimotor feedback delays, current accounts of grip force–load force coupling invoke explicit predictive mechanisms in the form of internal mode...

The ability to move one’s body from sitting to standing is a crucial ability for independent living. Especially for seniors with decreasing muscular strength, sit-to-stand (STS) transitions are exceptionally risky and often call for assistance. In general, an STS transition is a complex full-body activity that requires the synergistic coordination...

Behavioral dynamics models provide an observationally grounded basis for HRI algorithms and provide another tool for creating robust, natural, and interpretable HRI systems. Here, an HRI pick-and-place algorithm was implemented based on a behavioral dynamics model of human decision-making dynamics in an interpersonal pick-and-place task. Participan...

Humans often engage in tasks that require or are made more efficient by coordinating with other humans. The coordination involved in these tasks can be understood in terms of the behavioral and affordance dynamics of socially embedded agents engaged in joint action activities. Behavioral dynamics provide mathematical (differential equation) models...

Approximately 1.5 million senior citizens live under nursing supervision, and most require assistance with at least one or more Activities of Daily Living (ADL). These include transferring in and out of chairs, beds and toilets, which necessitates the ability to perform sit-to-stand transitions. The sit-to-stand transition is a complex full-body ac...

Physical cooperation between humans and robots has high potential impact in many critical application areas such as flexible manufacturing, mobility aids, rehabilitation , general service and medical robotics, education, and training. Among all robot control approaches for physical cooperation, goal-oriented robotic assistance based on human behavi...

Studies and concepts for social companion robots in therapy and care exist, however, they often lack the integration of convincing behavioral and social key mechanisms which enable a positive and successfull interaction experience. In this article we argue that synchrony and reciprocity are two key mechanisms of human interaction which affect both...

Ongoing technological advances in the areas of computation, sensing, and mechatronics enable robotic-based systems to interact with humans in the real world. To succeed against a human in a competitive scenario, a robot must anticipate the human behavior and include it in its own planning framework. Then it can predict the next human move and count...

With mobile robots moving into day to day life in private homes, care, or in public spaces and outdoors as robotic guides, Human-Robot Spatial Interaction (HRSI) - the study of joint movement of humans and robots and the social signals governing the interaction - becomes more and more important. The main focus of the workshop lies in incorporating...

Intuitive and effective physical assistance is an essential requirement for robots sharing their workspace with humans. Application domains reach from manufacturing and service robotics via rehabilitation and mobility aids to education and training. In this context, assistance based on human behavior anticipation has shown superior performance in t...

Unintentional movement synchronization is often emerging between interacting humans. In the present study, we investigate the extent to which the incongruence of movement trajectories has an influence on unintentional dyadic movement synchronization. During a target-directed tapping task, a participant repetitively moved between two targets in fron...

Interactive behavior among humans is governed by the dynamics of movement synchronization in a variety of repetitive tasks. This requires the interaction partners to perform for example rhythmic limb swinging or even goal-directed arm movements. Inspired by that essential feature of human interaction, we present a novel concept and design methodolo...

Interaction between robotic systems and humans becomes increasingly important in industry, the private and the public sector. A robot which plays pool against a human opponent involves challenges most human robot interaction scenarios have in common: planning in a hybrid state space, numerous uncertainties and a human counterpart with a different v...

Interpersonal movement synchronization is a phenomenon that does not only increase the predictability of movements; it also increases rapport among people. In this line, synchronization might enhance human-robot interaction. An experiment is presented which explores to what extend a human synchronizes own movements to a non-adaptive robot during a...

Proactive physical robotic assistance in the presence of human prediction uncertainty is a very challenging control problem. In this paper we propose a risk-sensitive optimal feedback controller for physical assistance that autonomously adapts the robot's behavior even during unknown situations. Using a probabilistic model to represent the cooperat...

In the future robots will more and more enter our daily life. If we want to increase their acceptance it is necessary that people feel safe in the surrounding of robots. As a prerequisite we think that the robot's behavior has to be legible in order to achieve such a feeling of perceived safety. With our present experiment we assess the perceived s...

The ability to infer intentions and predict actions enables coordinating of one's own actions with those of another human and allows smooth and intuitive interaction. The aim to achieve equally effective human-robot interactions is a crucial aspect of current robotic studies. Thus, we assume that studying human-human interaction provides valuable i...

Operating in the proximity of humans has been a long-term challenge in robotics research. To achieve this objective, one of the main issues is to ensure safe and comfortable physical human-robot interaction (pHRI). In this paper, we tackle the safety problem at the control level. To ensure operation is within perceived safe zone, we use model predi...

Human interaction partners tend to synchronize their movements during repetitive actions such as walking. Research of inter-human coordination in purely rhythmic action tasks reveals that the observed patterns of interaction are dominated by synchronization effects. Initiated by our finding that human dyads synchronize their arm movements even in a...

Robots will more and more enter our daily life. In order to increase their acceptance it is necessary that their movements and behavior are predictable. With our present experiment we assess the acceptance of autonomous robots in human working and living environments. As a specific indicator we define legibility as an important prerequisite for user...

Synchronization occurs frequently in human behaviour: Everybody has experienced that in a group of people walking pace tends to equalize. The phenomenon of synchrony has been established in the literature in tasks which have little in common with daily life such as pendulum swinging and chair rocking. We extend the knowledge about human movement sy...

This study examines how human movements are adapted when interacting with another person. It is also considered that the sequence of the movement can be to the choice of both actors. Different parameters of pick-and-place movements are compared in situations in which one person is moving alone or conjointly with a partner while the sequence of the...

Our goal is to assess the perceived value of autonomous robots in hu-man working and living environments. As a specific indicator we define legibility as an important prerequisite for high perceived value. Inspired by recommender systems, which also target the perceived value of products, we identify different measurements for explicit and implicit...