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The sense of agency refers to the feeling of control over one's own actions, and through them, the external events. This study examined the effect of modified visual feedback on the sense of agency over one's body movements using virtual reality in healthy individuals whose motor control was disturbed. Participants moved a virtual object using their right hand to trace a trajectory (Experiment 1) or a leading target (Experiment 2). Their motor control was disturbed by a delay in visual feedback (Experiment 1) or a 1-kg weight attached to their wrist (Experiment 2). In the offset conditions, the virtual object was presented at the median point between the desired position and the participants' actual hand position. In both experiments, participants reported improved sense of agency in the offset condition compared to the aligned condition where the visual feedback reflected their actual body movements, despite their motion being less precise in the offset condition. The results show that sense of agency can be enhanced by modifying feedback to motor tasks according to the goal of the task, even when visual feedback is discrepant from the actual body movements. The present study sheds light on the possibility of artificially enhancing body agency to improve voluntary motor control. [ABSTRACT FROM AUTHOR]

In robot teleoperation, a lack of depth information often results in collisions between the robots and obstacles in its path or surroundings. To address this issue, free viewpoint images can greatly benefit the operators in terms of collision avoidance as the operators are able to view the robot's surrounding from the images at arbitrary points, giving them a better depth information. In this paper, a novel free viewpoint image generation system is proposed. One approach to generate free viewpoint images is to use multiple cameras and Light Detection and Ranging (LiDAR). Instead of using the expensive LiDAR, this study utilizes a cost-effective laser rangefinder (LRF) and a characteristic of man-made environments. In other words, we install multiple fisheye cameras and an LRF on a robot. Free viewpoint images are generated under the assumption that walls are perpendicular to the floor. Furthermore, an easy calibration for estimating the poses of the multiple fisheye cameras, the LRF, and the robot model is proposed. Experimental results show that the proposed method can generate free viewpoint images using cameras and an LRF. Finally, the proposed method is primarily implemented using OpenGL Shading Language to utilize a graphics processing unit computation to achieve a real-time processing of the multiple high-resolution images. Supplementary videos and our source code are available at our project page (https://matsuren.github.io/fvp). [ABSTRACT FROM AUTHOR]

In order to smoothly interact with humans, it is desirable that a robot can guide human attention and behaviors. In this study, we developed a model of human visual attention for guiding human attention based on an analysis of a magic trick performance. We measured human gaze points of people watching a video of a magic trick performance and compared them with the area where the magician intended to draw a spectator's attention. The analysis showed that the relationship between the magician's face, hands, and gaze plays an important role in guiding the spectator's attention. On the basis of the preliminary user studies on watching the magic video, we integrated a saliency map and a manipulation map that describes the relationship between gaze and hands to develop a novel human attention model. The evaluation using the observed gaze points demonstrated that the proposed model can better explain human visual attention than the saliency map while people are watching a video of a magic trick performance. [ABSTRACT FROM AUTHOR]

For service robots coexisting with humans, both safety and working efficiency are very important. In order for robots to avoid collisions with surrounding obstacles, the robots must recognize obstacles around them. In dynamic environments, not only currently moving obstacles but also movable obstacles should be recognized. In this paper, three types of obstacles, such as stationary, movable and moving, are defined, and a method to identify the type of obstacles is proposed. The experiments using a mobile robot were conducted to evaluate the usefulness of the method. [ABSTRACT FROM AUTHOR]

Humans are capable of associating actions with their respective consequences if there is reliable contingency between them. The present study examined the link between the reliability of action consequence and the readiness potential (RP), which is a negative potential observed from about 1-2 s prior to the onset of an action with electroencephalography. In a condition of constant outcome, the participants’ voluntary action always triggered beep sounds; thus, they were able to perceive the contingency between their action and the sound. In contrast, in a condition of inconstant outcome, the participants’ actions only triggered the sound in half the trials. We found that both the early and late RPs were larger in the condition of constant compared to the condition of inconstant outcome. Our results showed that the RPs preceding the voluntary action reflected the reliability of action consequence. In other words, the action-effect contingency enhanced neural activities prior to the action. [ABSTRACT FROM AUTHOR]