waashk/dblp huggingface dataset:
automatic stimulation of experiments and learning based on prediction failure recognition. in this paper we focus on the task of automatically and autonomously initiating experimentation and learning based on the recognition of prediction failure. we present a mechanism that utilizes conceptual knowledge to predict the outcome of robot actions, observes their execution and indicates when discrepancies occur. we show how this mechanism was applied to a robot that learns using the paradigm of learning by experimentation, and present first results obtained from this implementation.
bilateral teleoperation with time delay using modified wave variable based controller. force-reflecting teleoperators in which the remote environment is kinesthetically coupled to the operator can considerably increase task performance. wave-variable-based controllers can support the stable operation of force-reflecting teleoperators under arbitrary communication delays. transparency in such systems is compromised in order to maintain stability. we had previously proposed a modified wave variable controller that implemented additional wave impedance in the wave variable transformations in order to focus more closely on force tracking. in this paper, we present a new controller for bilateral teleoperators based on the modified wave variable control method which provides superior position and force tracking performance compared to the traditional wave-variable-based method. moreover, the method has high stability. theoretical investigation and experimental results confirm the performance of this new controller.
vertical line matching for omnidirectional stereovision images. we are investigating the mobile robot indoor localization and environment mapping using an omnidirectional stereovision sensor. it uses four parabolic mirrors and an orthographic camera, giving four images of the same scene. at least, only two mirrors are needed. using four mirrors gives redundancy. we propose to exploit the images of vertical lines. this paper presents a new method in order to match these lines in the four images. contrary to existing approaches, we took into account the four sub-images existence in the design of this method, in order to exploit redundancy. this brought an original algorithm combining matching and pose estimation of vertical lines from the 3d environment. experimental results will be presented to validate this approach.
simultaneous localization of mobile robot and multiple sound sources using microphone array. sound source localization is an important function in robot audition. the existing works perform sound source localization using static microphone arrays. this work proposes a framework that simultaneously localizes the mobile robot and multiple sound sources using a microphone array on the robot. first, an eigenstructure-based generalized cross correlation method for estimating time delays between microphones under multi-source environments is described. a method to compute the far field source directions as well as the speed of sound using the estimated time delays is proposed. in addition, the correctness of the sound speed estimate is utilized to eliminate spurious sources, which greatly enhances the robustness of sound source detection. the arrival angles of the detected sound sources are used as observations in a bearings-only slam procedure. as the source signals are not persistent and there is no identification of the signal content, data association is unknown which is solved using fastslam. the experimental results demonstrate the effectiveness of the proposed approaches.
characterization of bacterial actuation of micro-objects. in recent years, flagellar motors of bacteria have not only inspired design of an entirely new category of microrobots, they have also been interfaced with synthetic components and used for controlled actuation of microscale objects. the ultimate goal of these efforts is to develop bio-hybrid swimming micro-robots which use bacteria for actuation, control, and sensing. as bacteria begin to become an integral part of microscale engineered systems, there is a great need for characterizing their performance and understanding the forces involved in interfacing them with synthetic components. in this work repeatability and endurance (performance as a function of time) of an ensemble of bacteria used for actuation of 10 µm polystyrene micro-beads are characterized. moreover, a series of adhesion assay methods are introduced and used to determine the strength and timeline of adhesion of serratia marcescens (s. marcescens) bacteria to hydrophobic and hydrophilic polystyrene surfaces.
on-chip detection and separation of micro-particles using magnetized microtools driven by focused magnetic field. we succeeded in powerful noncontact actuation of magnetically driven microtool (mmt) by magnetizing it and focusing magnetic field in a microfluidic chip. novelty of this paper is summarized as follows. (1) we employed neodium powder as the main component of mmt. the density of magnetic flux was improved about 100 times larger after magnetization. (2) we fabricated a pair of magnetic sharp needles in the chip by electroplating. mmt was placed between the needles and the density of magnetic flux was improved about 3 times larger. as a result, we succeeded in powerful actuation of mmt in a chip. drive frequency was improved about 10 times faster (up to 180 hz). we applied it for sorting of copolymer beads in a chip. mmt is put in the microchannel. the size of the bead was measured by image processing (15 hz). moving frequency of the mmt was made higher than the sampling frequency of measurement and secure sorting was achieved.
real-time positioning and tracking technique for endovascular untethered microrobots propelled by mri gradients. a real-time positioning and tracking technique for untethered devices or robots magnetically propelled by a clinical magnetic resonance imaging (mri) system is described. the local magnetic field induced by the device, composed of a ferromagnetic material, is used as a signature to localize the device on three one-dimensional projections. a high-precision 3d circular-motion system was used to assess the precision and accuracy of this method. the integration of this technique inside propulsion and imaging mri sequences was also achieved to demonstrate the feasibility of this tracking scheme in a closed-loop control scheme. finally, in vivo tracking during automatic navigation of an untethered device in the carotid artery of a living animal is demonstrated.
generating robot/agent backchannels during a storytelling experiment. this work presents the development of a real-time framework for the research of multimodal feedback of robots/talking agents in the context of human robot interaction (hri) and human computer interaction (hci). for evaluating the framework, a multimodal corpus is built (enterface stead), and a study on the important multimodal features was done for building an active robot/agent listener of a storytelling experience with humans. the experiments show that even when building the same reactive behavior models for robot and talking agents, the interpretation and the realization of the behavior communicated is different due to the different communicative channels robots/agents offer be it physical but less human-like in robots, and virtual but more expressive and human-like in talking agents.
fabrication and feedback control of an articulated microarm. as cancer becomes the no.1 cause of the death in japan, endoscopic surgery is gaining attentions. in this paper, endoscopical tool to grip and lift the targeted tumor in esd (endoscopic submucosal dissection) surgery is proposed. this articulated microarm is part of new esd surgery concept in which two wire-driven microarms (1 × 1 × 25 mm) from the tip of the endoscope help lift the tumor to cut. this research needs to emphasize a new fabrication method of arm which is fabricated by photolithography and electroplating. the microarm is composed of five layers. individual layers are fabricated separately and assembled together in the end. the microarm uses the elastic deformation of metal to bend (cu or phosphor bronze). it is feedback control with pid using a strain gauge attached to the articulated joint. this technique enabled the further miniaturization of the microarm, but it also comes with a downside. it is difficult to build a 3-dimensional structure. we overcame this problem by proposing an assembly method (stamp: stacked microassembly process). electroplated layers are assembled by stacking up on top of each other. this assembly process is feasible to produce multiple microarms at one assembly, thus mass-production with low cost is possible. a strain gauge is attached to the elastic joint as an angle sensor.
development of a climbing robot for grit blasting operations in shipyards. this paper deals with the design and construction of a climbing robot for performing grit blasting operations in shipyards. the robot is based on a double sliding platform that uses permanent magnets for attachment. it is lightweight and compact and can move up and along the shipside with any inclination while grit blasting the surface to pre-specified surface quality levels. it can also rotate to compensate for hull curvature and to avoid obstacles while performing its task. the blasting operation is modulated by a vision based quality control system that is used by the mission control system to adapt the blasting parameters in order to attain the desired quality levels while maximizing the surface area the robot strips per unit time.
dynamic estimation of homography transformations on the special linear group for visual servo control. in the last decade, many vision-based robot controllers have been designed using cartesian information encoded in the homography transformation that links two images of a planar object. for any approach, the performance of the closed-loop system depends on the quality of the homography estimates obtained. in this paper, we exploit the special linear lie-group structure of the set of all homographies to develop a dynamic observer to estimate homographies on-line. the resulting estimates are effective and can be used to improve closed-loop response of several visual servoing algorithms.
consistent cooperative localization. in cooperative navigation, teams of mobile robots obtain range and/or angle measurements to each other and dead-reckoning information to help each other navigate more accurately. one typical approach is moving baseline navigation, in which multiple autonomous underwater vehicles (auvs) exchange range measurements using acoustic modems to perform mobile trilateration. while the sharing of information between vehicles can be highly beneficial, exchanging measurements and state estimates can also be dangerous because of the risk of measurements being used by a vehicle more than once; such data re-use leads to inconsistent (overconfident) estimates, making data association and outlier rejection more difficult and divergence more likely. in this paper, we present a technique for the consistent cooperative localization of multiple auvs performing mobile trilateration. each auv establishes a bank of filters, performing careful bookkeeping to track the origins of measurements and prevent the use any of the measurements more than once. the multiple estimates are combined in a consistent manner, yielding conservative covariance estimates. the technique is illustrated using simulation results. the new method is compared side-by-side with a naive approach that does not keep track of the origins of measurements, illustrating that the new method keeps conservative covariance bounds whereas state estimates obtained with the naive approach become overconfident and diverge.
a dynamic programming approach to multi-level supervision. using dynamic programming (dp), this paper presents a multi-level supervisory control implementation in the standard hierarchical discrete-event control framework. for a class of hierarchically consistent discrete-event systems, the dp algorithm developed implements a multi-level nonblocking controller with reduced off-line complexity of control synthesis and increased on-line transparency of control operations. an example illustrates the on-line control operations of the algorithm.
tracking of facial features to support human-robot interaction. in this paper we present a novel methodology for detection and tracking of facial features like eyes, nose and mouth in image sequences. the proposed methodology is intended to support natural interaction with autonomously navigating robots that guide visitors in museums and exhibition centers and, more specifically, to provide input for the analysis of facial expressions that humans utilize while engaged in various conversational states. for face and facial feature region detection and tracking, we propose a methodology that combines appearance-based and feature-based methods for recognition and tracking, respectively. for the stage of face tracking the introduced method is based on least squares matching (lsm), a matching technique able to model effectively radiometric and geometric differences between image patches in different images. thus, compared with previous research, the lsm approach can overcome the problems of variable scene illumination and head in-plane rotation. another significant characteristic of the proposed approach is that tracking is performed on the image plane only wherever laser range information suggests so. the increased computational efficiency meets the real time demands of human-robot interaction applications and hence facilitates the development of relevant systems.
comparison of local image descriptors for full 6 degree-of-freedom pose estimation. recent years have seen advances in the estimation of full 6 degree-of-freedom object pose from a single 2d image. these advances have often been presented as a result of, or together with, a new local image descriptor. this paper examines how the performance for such a system varies with choice of local descriptor. this is done by comparing the performance of a full 6 degree-of-freedom pose estimation system for fourteen types of local descriptors. the evaluation is done on a database with photos of complex objects with simple and complex backgrounds and varying lighting conditions. from the experiments we can conclude that duplet features, that use pairs of interest points, improve pose estimation accuracy, and that affine covariant features do not work well in current pose estimation frameworks. the data sets and their ground truth is available on the web to allow future comparison with novel algorithms.
aerodynamics and control of autonomous quadrotor helicopters in aggressive maneuvering. quadrotor helicopters have become increasingly important in recent years as platforms for both research and commercial unmanned aerial vehicle applications. this paper extends previous work on several important aerodynamic effects impacting quadrotor flight in regimes beyond nominal hover conditions. the implications of these effects on quadrotor performance are investigated and control techniques are presented that compensate for them accordingly. the analysis and control systems are validated on the stanford testbed of autonomous rotorcraft for multi-agent control quadrotor helicopter testbed by performing the quadrotor equivalent of the stall turn aerobatic maneuver. flight results demonstrate the accuracy of the aerodynamic models and improved control performance with the proposed control schemes.
mobility reconfiguration for terrain exploration using passive perception. the ability of robotic units to autonomously navigate various terrains is critical to the advancement of robotic operation in natural environments. next generation robots will need to adapt to their environment in order to accomplish tasks that are either too hazardous, too time consuming, or physically impossible for human-beings. such tasks may include accurate and rapid explorations of various planets or potentially dangerous areas on earth. furthermore, because terrain variability typically increases as the distance that a rover traverses increases, it will be beneficial for robotic units to adapt to their surroundings. as a result, this research investigates a navigation control methodology for a multi-modal locomotive robot based upon passive perception. surface estimation for robot reconfigurability is implemented using a region growing method, which characterizes the traversability of the terrain, in conjunction with passive perception regarding motion. a mathematical approach is then implemented that inherits human psychological aspects to direct necessary navigation behavior to control robot mobility. physical experimentations in a simulated mars yard are presented to validate the methodology.
leader-follower formation control of underactuated auvs with leader position measurement. in this paper, we investigate the leader-follower formation control of underactuated autonomous underwater vehicles (auvs). by using position measurements from the leader, we design a virtual vehicle such that the trajectory of the virtual vehicle converges to the reference trajectory of the follower. a position tracking control is designed for the follower to track the virtual vehicle using lyapunov and backstepping synthesis. simulation results demonstrated the effectiveness of the proposed scheme.
design and development of a low-cost flexure-based hand-held mechanism for micromanipulation. this paper presents a 3-dof low-cost hand-held micromanipulator driven by 3 piezoelectric actuators and built using rapid prototyping. traditional pin and ball joints have been commonly replaced by flexure-based methods in the field of micromanipulation. utilization of flexure-based joints have several advantages like the non-existence of backlash and assembly errors. however, most of the present flexure-based mechanisms are bulky and not suitable for hand-held applications. it is difficult and expensive to make such compact mechanism using traditional machining methods. in additional, traditional machining methods are limited to simple design. to reduce the cost of fabrication and also to allow more complex designs, objet (a rapid prototyping machine) is proposed to be used to build the mechanism. with regards to hand-held applications, the size of the mechanism is a constraint. hence, a parallel manipulator design is the preferred choice as compared to a serial mechanism because of its rigidity, compactness, and simplicity in design. for the illustration of an application, the mechanism is designed with an intraocular needle attached to it. possible applications of this design include enhancement of performance in microsurgery and cell micromanipulation. experiments are also conducted to evaluate the manipulator's tracking performance of the needle tip at a frequency of 10hz.
quantitative assessment of the surgical training methods with the suture/ligature training system wks-2rii. the emerging field of medical robotics is aiming in introducing intelligent tools to perform medical procedures. in particular, robotic researchers have been proposed advanced medical training systems to enhance motor dexterities of trainees. an efficient medical training system should be designed to simulate real-world conditions and to assure their effectiveness as the representation of the motor skills often differs among trainees. up to now, several training simulators have been developed by medical companies designed to reproduce with high fidelity the human body. however, such devices are not designed to provide any information to trainees. therefore, we have proposed the development of a patient robot which embeds sensors and actuators into a conventional human model. due to its complexity, as a first approach; we are presenting the development of a suture training system designed to simulate the real-world task conditions as well as providing quantitative assessments. in particular; the waseda-kyotokagaku suture no.2 refined ii is presented, which includes a new evaluation function to provide more detailed information of the task. a set of experiments were proposed to analyze the performance of trainees. from the experimental results, we could confirm its effectiveness to detect differences of the performance of trainees.
a nonlinear observer for 6 dof pose estimation from inertial and bearing measurements. this paper considers the problem of estimating pose from inertial and bearing-only vision measurements. we present a non-linear observer that evolves directly on the special euclidean group se(3) from inertial measurements and bearing measurements, such as provided by a visual system tracking known landmarks. local asymptotic convergence of the observer is proved. the observer is computationally simple and its gains are easy to tune. simulation results demonstrate robustness to measurement noise and initial conditions.
the role of small redundant actuators in precise manipulation. with the goal of developing humanlike dextrous manipulation, we investigate how the central nervous system uses the redundant control space of the human hand to perform tasks with force-stiffness requirements. specifically, while the human hand is actuated by several muscles with varying mechanical advantage (called the moment arm), it is unclear how each muscle is used. using the anatomically correct testbed (act) robotic hand to compute the control solution space and human-subject experiments with surface electromyography to measure biological control strategy, we identified that there is significant redundancy in the control spaces of both muscles with large moment arms and muscles with small moment arms. however, the central nervous system was selective about the solution for muscles with large moment arms, while it chose to span large regions of the available control space for muscles with small moment arms. furthermore, the biological solution used low-moment-arm muscles at relatively high actuation levels. we summarize by making inferences on why the central nervous system chooses such a strategy and how this can help robotic manipulation.
global vector field computation for feedback motion planning. we present a global vector field computation algorithm in configuration spaces for smooth feedback motion planning. our algorithm performs approximate cell decomposition in the configuration space and approximates the free space using rectanguloid cells. we compute a smooth local vector field for each cell in the free space and address the issue of the smooth composition of the local vector fields between the non-uniform adjacent cells. we show that the integral curve over the computed vector field is guaranteed to converge to the goal configuration, be collision-free, and maintain c∞ smoothness. as compared to prior approaches, our algorithm works well on non-convex robots and obstacles. we demonstrate its performance on planar robots with 2 or 3 dofs, articulated robots composed of 3 serial links and multi-robot systems with 6 dofs.