In this study, we propose to explore inverse optimization process to better understand human arm motion in industrial screwing task. the process combines several criteria to minimize such as energy expenditure or traj...
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In this study, we propose to explore inverse optimization process to better understand human arm motion in industrial screwing task. the process combines several criteria to minimize such as energy expenditure or trajectory smoothness leading to the optimal trajectory of a typical screwing task, often performed by workers. Estimated joint trajectories are similar withthe measured ones, with a mean square error of 4 degrees. the resulting cost-function is mainly composed of energy expenditure and geodesic criteria. Results show the relevance of using composite cost function in human motion planning. this study has been conducted to assist workers by using collaborative robots in painful task in PSA Peugeot Citroen factories to improve ergonomics of manual workstations.
In many industries where automation and robotics is used artificial muscles are used. Analyses of their properties give a precondition for the most efficient use in this area. It is therefore important for students to...
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In many industries where automation and robotics is used artificial muscles are used. Analyses of their properties give a precondition for the most efficient use in this area. It is therefore important for students to have the opportunities to observe and analyse their characteristics. the aim of this contribution will be to design the user interface to simulate selected properties of artificial muscles. Matlab with its powerful simulation tools will be used there.
the authors present in this paper a robust torque control of an active orthosis designed to assist the knee joint flexion/extension during physical therapy. the orthosis is driven by a rotary Series Elastic Actuator p...
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the authors present in this paper a robust torque control of an active orthosis designed to assist the knee joint flexion/extension during physical therapy. the orthosis is driven by a rotary Series Elastic Actuator presented in authors' previous paper. the adopted control strategy is based on H ∞ criterion in order to ensure good system performance even when it is subjected to parametric uncertainties and external disturbances. the controller performance is evaluated through the frequency response function analysis. Experimental results involving the interaction between a subject and the active knee orthosis are also presented to show the performance of the developed prototype.
Single-track vehicles including unicycles and bicycles are unstable, and require human riding skill and practice for acquiring the skill. Sometimes the practice of single-track vehicle may be difficult in many situati...
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ISBN:
(纸本)9781479952007
Single-track vehicles including unicycles and bicycles are unstable, and require human riding skill and practice for acquiring the skill. Sometimes the practice of single-track vehicle may be difficult in many situations for beginners because it becomes relatively terrible and is difficult to carry on continuously. A unicycle simulator and a power-assist system for bicycles have been developed in this project. the dynamics of the simulator and the dynamics of the assisted bicycle can be adjusted according to a trainee, and they allow trainee to exercise effectively.
Percutaneous surgical procedures depend on the precise positioning of the needle tip for effectiveness. Although, robustly locating the tip of the needle still represents a challenge, specially when flexible needles a...
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Percutaneous surgical procedures depend on the precise positioning of the needle tip for effectiveness. Although, robustly locating the tip of the needle still represents a challenge, specially when flexible needles are used. An imaging technique widely used for this task is 2D ultrasound, however the low signal/noise ratio makes it difficult to apply conventional image processing techniques. In this work, we propose an alternative method for detecting the needle in an ultrasound image and tracking it during a complete insertion. the proposed method combines a Multilayer Perceptron network with a Kalman filter estimator for improving robustness. In preliminary experimental characterization, we acquired ultrasound images for creating the data set and evaluated the performance of the tracker with a complete insertion video. However the tracking performance is still far from optimal, the obtained results suggests the neural network approach to be a feasible alternative to this problem.
Nowadays, robotic-assisted surgery does not allow beating heart surgery with autonomous motion compensation functionalities. this paper tackles this problem, based on a robotic control architecture that relies on forc...
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Nowadays, robotic-assisted surgery does not allow beating heart surgery with autonomous motion compensation functionalities. this paper tackles this problem, based on a robotic control architecture that relies on force feedback. the algorithm merges two cascade loops. the inner one is based on the Kalman active observer (AOB), performing model-reference adaptive control to impose a well-defined stable plant. the outer one, based on a model predictive control (MPC) approach, generates control references for beating heart motion compensation. Two robots are used in the experiments. A lightweight 4-DoF surgical robot generates desired surgical forces and a 3-DoF robot equipped with an ex vivo heart at the end-effector reproduces realistic heart motion. Additionally, robustness to cardiac stiffness mismatches is analyzed.
An effective speech brain machine interface requires selecting the best cortical recording sites and signal features for decoding speech production, but also minimal clinical risk for the patient. Motivated by this ne...
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ISBN:
(纸本)9781479952007
An effective speech brain machine interface requires selecting the best cortical recording sites and signal features for decoding speech production, but also minimal clinical risk for the patient. Motivated by this need to reduce patient risk, the purpose of this study is to detect voice activity (speech onset and offset) automatically from spatial-spectral features of electrocorticographic signals using the optimal number of sensors (minimal invasiveness). ECoG signals were recorded while a subject performed two different syllable repetition tasks. We found that the optimal frequency resolution for detecting voice activity is 8 Hz using 31 sensors out of 55, achieving 98.2% accuracy by employing support vector machines (SVM) as a classifier, and that acceptable accuracy of 96.7% was achieved using 15 sensors, which would permit a less invasive surgery for the placement of electrodes. the proposed voice activity detector may be utilized as a part of an ECoG-based automated natural speech BMI system.
the gamification of serious games is a successful and ongoing trend that aims to involve even the latest generation of users to help them improve certain cognitive abilities. A valid path of further improving such gam...
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the gamification of serious games is a successful and ongoing trend that aims to involve even the latest generation of users to help them improve certain cognitive abilities. A valid path of further improving such games would be through implementing real-time feedback from the users into certain gameplay aspects. Physiological signals can provide a direct route to the current state of the user without any overt interaction between the device and the player. Here we outline a framework that aims to dynamically adjust the difficulty of serious games based on physiological signals.
this paper presents a system to supervise tissue temperature during robotic laser surgery. the use of robotic systems for laser surgery provides mechanisms to controlthe motion of the laser beam and the exposure time...
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this paper presents a system to supervise tissue temperature during robotic laser surgery. the use of robotic systems for laser surgery provides mechanisms to controlthe motion of the laser beam and the exposure time of laser radiation, allowing the automatic generation of incisions. this work focuses on the perception side of the problem, developing a technology for the online verification of the thermal state of the tissue during robotic laser microsurgery. Obtaining this information is paramount to enable automatic control of laser incision quality, which is directly related to tissue temperature. A model learned from real data estimates the change in temperature given the exposure time and power of the laser. the model is implemented in the real system and validated during laser incisions on ex-vivo tissue. Results show that the model can reliably estimate the thermal state of the tissue in real-time, and thus is suitable to produce feedback for automatic control of laser incisions.
Unmanned aerial vehicles (UAVs) have many applications and quickly gain popularity withthe availability of low-cost micro aerial vehicles (MAVs). robotics is a popular interdisciplinary education target as it involve...
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Unmanned aerial vehicles (UAVs) have many applications and quickly gain popularity withthe availability of low-cost micro aerial vehicles (MAVs). robotics is a popular interdisciplinary education target as it involves understanding and collaboration of several disciplines. thus, UAVs can serve as an ideal study platform. However, as robotics requires technical background, skills and initial efforts, it is commonly applied in long-term courses. In this paper we successfully exploit the opposite case of robotics in short-term education for students without background, in form of a one-day contest on automatic visual UAV navigation. We provide an extensive survey, and show that existing material and tools do not fit the task and lack in technical aspects. We introduce a novel open-source programming library that comprises programs to guide learning by experience and allow rapid development. It makes contributions to marker-based tracking, with a novel nested-marker design and accurate calibration parameters estimated from 14 Parrot *** 2.0 front cameras. We show a detailed discussion of the contest results, which represents an extensive user study regarding robotics in education and the effectiveness of the library. the achievement of a steep learning curve for a complex subject has important implications in interdisciplinary design education, as it allows deep understanding of potentials and limitations to facilitate decision-making, unconventional problem solutions and novel applications.
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