Programming-by-demonstration and adaptation of robot skills by fuzzy-time-modeling

Proceedings of: 2011 IEEE Workshop on Robotic Intelligence in Informationally Structured Space (RiiS 2011 MDCM), April 11-15, 2011, Paris (France)Complex robot tasks can be partitioned into motion primitives or robot skills that can directly be learned and recognized through Programming-by-Demonstration (PbD) by a human operator who demonstrates a set of reference skills. Robot motions are recorded by a data-capturing system and modeled by a specific fuzzy clustering and modeling technique where skill models use time instants as inputs and operator actions as outputs. In the recognition phase the robot identifies the skill shown by the operator in a novel test demonstration. Skill models are updated online during the execution of skills using the Broyden update formula. This method is extended for fuzzy models especially for time cluster models. The updated model is used for further executions of the same skill.European Community's Seventh Framework Progra

Programming-by-demonstration of reaching motions for robot grasping

Proceedings of: 14th International Conference on Advanced Robotics (ICAR 2009), 22-26 June 2009, Munich (Germany)This paper presents a novel approach to skill modeling acquired from human demonstration. The approach is based on fuzzy modeling and is using a planner for generating corresponding robot trajectories. One of the main challenges stems from the morphological differences between human and robot hand/arm structure, which makes direct copying of human motions impossible in the general case. Thus, the planner works in hand state space, which is defined such that it is perception-invariant and valid for both human and robot hand. We show that this representation simplifies task reconstruction and preserves the essential parts of the task as well as the coordination between reaching and grasping motion. We also show how our approach can generalize observed trajectories based on multiple demonstrations and that the robot can match a demonstrated behavoir, despite morphological differences. To validate our approach we use a general-purpose robot manipulator equipped with an anthropomorphic three-fingered robot hand.European Community's Seventh Framework Progra

Evaluation of a male-specific psychotherapeutic program for major depressive disorder compared to cognitive behavioral therapy and waitlist: study protocol for a six-arm randomized clinical superiority trial examining depressed eugonadal and hypogonadal men receiving testosterone

BACKGROUND: Treatment of major depressive disorder (MDD) in men is complicated by the endorsement of traditional masculinity ideologies (TMI) often leading to reluctance toward psychotherapy, therapy interfering processes, or premature termination. In addition, it has been shown that men with MDD have a significantly increased risk of being hypogonadal (e.g., total testosterone levels <12.1 nmoL/L). Therefore, it is recommended to examine depressed men with regard to their testosterone status and if hypogonadism is present to combine psychotherapy with testosterone treatment (TT). AIM: This project aims to evaluate a male-specific psychotherapeutic program (MSPP) for MDD in depressed eugonadal and hypogonadal men receiving testosterone in comparison to a standard cognitive behavioral therapy (CBT) for MDD and a Waitlist. METHODS: The study presents a 2×3 factorial study design. In total, 144 men aged between 25 and 50 will be stratified by testosterone status (eugonadal/hypogonadal) and then randomized into one of the three conditions (MSPP, CBT, or Waitlist). Additionally, a healthy control group of 100 men will be recruited, which will undergo only baseline assessments. Both standardized psychotherapy programs will encompass 18 sessions delivered in a weekly manner. Aligned with the TT-related medical visits of the 72 hypogonadal men, all participants will be followed up with clinical assessments and bio sampling at weeks 0, 6, 15, 24, and 36. EXPECTED RESULTS: Compared to Waitlist control groups, treatment groups are expected to be more effective and efficacious (depression score reduction of ≥50%) at week 24 and at the follow-up at week 36. The MSPP is expected to show higher effectiveness and efficacy for depressive symptoms and higher acceptability (lower dropout rate) as compared to CBT. DISCUSSION: This study represents the first attempt to test a male-specific psychotherapy for MDD in a single-setting compared to standard CBT and a Waitlist control condition using randomized clinical trial methodology. In addition, the potential positive adjunct effect of psychotherapy to TT in reducing depressive burden and improving quality of life in hypogonadal depressed men represents a neglected research area and might introduce new hypogonadism screening procedures in depressed men and combined treatment approaches for depressed men suffering from hypogonadism. Limitations are the rigorous inclusion and exclusion criteria, which limit the generalizability of the study results to first episode treatment naïve depressed men. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT05435222

Rapid cross-border emergence of NDM-5-producing Escherichia coli in the European Union/European Economic Area, 2012 to June 2022

Whole genome sequencing data of 874 Escherichia coli isolates carrying blaNDM-5 from 13 European Union/ European Economic Area countries between 2012 and June 2022 showed the predominance of sequence types ST167, ST405, ST410, ST361 and ST648, and an increasing frequency of detection. Nearly a third (30.6%) of these isolates were associated with infections and more than half (58.2%) were predicted to be multidrug-resistant. Further spread of E. coli carrying blaNDM-5 would leave limited treatment options for serious E. coli infections

Decreased Reward Sensitivity in Rats from the Fischer344 Strain Compared to Wistar Rats Is Paralleled by Differences in Endocannabinoid Signaling

BACKGROUND: The aim of the present study was to examine if differences in the endocannabinoid (ECB) system might be linked to strain specific variations in reward-related behavior in Fischer344 (Fischer) and Wistar rats. METHODOLOGY/PRINCIPAL FINDINGS: Two rat strains, the Fischer and the Wistar strain, were tested for different aspects of reward sensitivity for a palatable food reward (sweetened condensed milk, SCM) in a limited-access intake test, a progressive ratio (PR) schedule and the pleasure-attenuated startle (PAS) paradigm. Additionally, basic differences in the ECB system and cannabinoid pharmacology were examined in both rat strains. Fischer rats were found to express lower reward sensitivity towards SCM compared to Wistar rats. These differences were observed for consummatory, motivational and hedonic aspects of the palatable food reward. Western blot analysis for the CB1 receptor and the ECB degrading enzyme fatty acid amide hydrolase (FAAH) revealed a lower expression of both proteins in the hippocampus (HPC) of Fischer rats compared to the Wistar strain. Furthermore, increased cannabinoid-stimulated extracellular-regulated kinase (ERK) phosphorylation was detected in Wistar rats compared to the Fischer strain, indicating alterations in ECB signaling. These findings were further supported by the pharmacological results, where Fischer rats were found to be less sensitive towards the effects of the CB1 receptor antagonist/inverse agonist SR141716 and the cannabinoid agonist WIN 55,212-2. CONCLUSIONS/SIGNIFICANCE: Our present findings indicate differences in the expression of the CB1 receptor and FAAH, as well as the activation of ECB signaling pathways between Fischer and Wistar rats. These basic differences in the ECB system might contribute to the pronounced differences observed in reward sensitivity between both rat strains

Fluid mechanics for path planning and obstacle avoidance of mobile robots

Obstacle avoidance is an important issue for off-line path planning and on-line reaction to unforeseen appearance of obstacles during motion of a non-holonomic mobile robot along apredefined trajectory. Possible trajectories for obstacle avoidance are modeled by the velocity potential using a uniform flow plus a doublet representing a cylindrical obstacle. In the case of an appearance of an obstacle in the sensor cone of the robot a set of streamlines is computed from which a streamline is selected that guarantees a smooth transition from/to the planned trajectory. To avoid collisions with other robots a combination of velocity potential and force potential and/or the change of streamlines during operation (lane hopping) are discussed.SAUNA - Safe Autonomous Navigatio

Velocity potentials and fuzzy modeling of fluid streamlines for obstacle avoidance of mobile robots

The use of the velocity potential of an incompressible fluid is an important and elegant tool for obstacle avoidance of mobile robots. Obstacles are modeled as cylindrical objects - combinations of cylinders can also form super obstacles. Possible trajectories of a vehicle are given by a set of streamlines around the obstacle computed by the velocity potential. Because of the number of streamlines and of data points involved therein, models of sets of streamlines for different sizes of obstacles are created first using dataset models and finally fuzzy models of streamlines. Once an obstacle appears in the sensor cone of the robot the set of streamlines is computed from which that streamline is selected that guarantees a smooth transition from/to the planned trajectory. Collisions with other robots are avoided by a combination of velocity potential and force potential and/or the change of streamlines during operation (lane hopping).AI

Particle swarm optimization of potential fields for obstacle avoidance

This paper addresses the safe navigation of multiple nonholonomic mobile robots in shared areas. Obstacle avoidance for mobile robots is performed by artificial potential fields and special traffic rules. In addition, the behavior of mobile robots is optimized by particle swarm optimization (PSO). The control of non-holonomic vehicles is performed using the virtual leader principle together with a local linear controller