Natural Orifice Transluminal Endoscopic Surgery (NOTES) is a method that allows for performing complex operations via natural orifices without skin incisions. Its main tool is a flexible endoscope. Cable-Conduit Mecha...
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Natural Orifice Transluminal Endoscopic Surgery (NOTES) is a method that allows for performing complex operations via natural orifices without skin incisions. Its main tool is a flexible endoscope. Cable-Conduit Mechanisms (CCMs) are often used in NOTES because of its simplicity, safety in design, and easy transmission. Backlash hysteresis nonlinearities between the cable and the conduit pose difficulties in the motion control of the NOTES system. It is challenging to achieve the precise position of robotic arms when the slave manipulator inside the humans body. This paper presents new approaches to model and control for pairs of CCMs. It is known that the change of cable-conduit configuration will affect the backlash hysteresis non-linearities. To deal with such change, a new nonlinear and adaptive control scheme will be introduced. The backlash hysteresis parameters are online estimated under the assumption of availability of output feedback and unknown bound of nonlinear parameters. To validate the proposed approach, a prototype of single-DOF-Master-Slave system, which consists of a master console, a telesurgical workstation, and a slave manipulator, is also presented. The proposed compensation scheme is experimentally validated using the designed system. The results show that the proposed control scheme efficiently improves the tracking performances of the system regardless of the change of endoscope configuration.
Interval estimation design for a class of parametric varying systems is considered. Interval state observer for nonlinear system with varying parameters and constant time delay is proposed. Also we consider the case w...
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Interval estimation design for a class of parametric varying systems is considered. Interval state observer for nonlinear system with varying parameters and constant time delay is proposed. Also we consider the case with unknown unmeasured perturbations and check the behavior of the interval estimates into simulations. The efficiency of this method is shown through computer modelling of a hormone testosterone dynamics system in the presence of time delay and disturbances.
The proceedings contain 12 papers. The topics discussed include: applying artificial neural networks to promote behaviour change for saving residential energy;input-output characteristics of LIF neuron with dynamic th...
ISBN:
(纸本)9789897580413
The proceedings contain 12 papers. The topics discussed include: applying artificial neural networks to promote behaviour change for saving residential energy;input-output characteristics of LIF neuron with dynamic threshold and short term synaptic depression;a novel neural network computing based way to sensor and method fusion in harsh operational environments;new learning rules for three-layered feed-forward neural networks based on a general learning schema;localization of visual codes in the DCT domain using deep rectifier neural networks;'mind reading': hitting cognition by using ANNs to analyze fMRI data in a paradigm exempted from motor responses;neural network based complex visual information processing: face detection and recognition;neural networks based local weather prediction system;traveling salesman problem solutions by using passive neural networks;and simplified information acquisition method to improve prediction performance: direct use of hidden neuron outputs and separation of information acquisition and use phase.
To efficiently explore a surface using the sense of touch, a novel contact sensing finger was created and a surface following control algorithm for the finger was devised. Based on the accurate estimation of contact l...
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To efficiently explore a surface using the sense of touch, a novel contact sensing finger was created and a surface following control algorithm for the finger was devised. Based on the accurate estimation of contact locations, and the direction and magnitude of the normal and tangential forces, the finger can robustly and rapidly follow surfaces with large change in curvature while maintaining a desired constant normal force. In this paper, the design and testing of the contact sensing finger are presented and the control algorithm for surface contour following is proposed and validated using objects with different shapes and surface materials. The results demonstrate that using the developed finger and the control algorithm, a surface can be efficiently explored with rapid sliding speed. To demonstrate the potential applications of the proposed approach, the friction properties of an explored object surface are computed and, for a known object, its pose is estimated.
This video presents our preliminary work towards addressing the ladder climbing event in DARPA robotics Challenge (DRC) using DRC-Hubo robot. A ladder-climbing motion planner is developed which generates a collision-f...
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This video presents our preliminary work towards addressing the ladder climbing event in DARPA robotics Challenge (DRC) using DRC-Hubo robot. A ladder-climbing motion planner is developed which generates a collision-free, stable quasi-static trajectory for execution. Compliance control is enabled on arm joints to compensate for the calibration error, modeling error and control error. We have demonstrated that DRC-Hubo can robustly climb a variety of ladders in simulation and successfully climb a ship ladder on the hardware.
The problem of simulation combined adaptive control system for scalar dynamic plant in periodical modes is discussed. With the help of computer simulation selects coefficients of the regulator, providing high-quality ...
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ISBN:
(纸本)9781784660468
The problem of simulation combined adaptive control system for scalar dynamic plant in periodical modes is discussed. With the help of computer simulation selects coefficients of the regulator, providing high-quality system performance.
Aircraft are non-minimum phase, MIMO and highly nonlinear systems which undergo significant disturbances and variation in system parameters during operation. In spite of the prosperous literature in adaptive control, ...
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ISBN:
(纸本)9781479952007
Aircraft are non-minimum phase, MIMO and highly nonlinear systems which undergo significant disturbances and variation in system parameters during operation. In spite of the prosperous literature in adaptive control, application of the promising control strategy on aircraft control has been restricted by the lack of assurance in closed-loop stability. This paper proposes a robust adaptive control scheme for aircraft. The scheme is composed of an inner-level adaptive fuzzy PD control law and an outer-level supervisory control law. Importantly, the outer-level controller of the two-level scheme is designed based on a fuzzy model which takes non-minimum phase phenomena and modeling error explicitly into account. Numerical studies of the tracking control of a five degree of freedom aircraft system demonstrate the effectiveness of the proposed control strategy in the face of bursting disturbances.
This paper demonstrates that singular configuration of a two-link robot arm is advantageous in doing the task of pulling or lifting up a heavy object with small joint torques. As a result of numerical optimization, th...
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This paper demonstrates that singular configuration of a two-link robot arm is advantageous in doing the task of pulling or lifting up a heavy object with small joint torques. As a result of numerical optimization, the initial configuration that minimizes the joint torques necessary for the task is close to the singular configuration where the arm is stretched out. The singular configuration has the dynamic feature that the joint angle vector can be accelerated in a certain direction almost independently of the mass of the object. Then, the joint torques can generate large kinetic energy efficiently at the singular configuration, and the energy can be utilized to pull or lift up the object. The experimental results show that the dynamic feature is practically useful, even when a feedback control is applied in order to make the object follow a planned trajectory.
We study the problem of revising specifications with preferences for automata based control synthesis problems. In this class of revision problems, the user provides a numerical ranking of the desirability of the subg...
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We study the problem of revising specifications with preferences for automata based control synthesis problems. In this class of revision problems, the user provides a numerical ranking of the desirability of the subgoals in their specifications. When the specification cannot be satisfied on the system, then our algorithms automatically revise the specification so that the least desirable user goals are removed from the specification. We propose two different versions of the revision problem with preferences. In the first version, the algorithm returns an exact solution while in the second version the algorithm is an approximation algorithm with non-constant approximation ratio. Finally, we demonstrate the scalability of our algorithms and we experimentally study the approximation ratio of the approximation algorithm on random problem instances.
During the last decade, the Collaborative Manufacturing research domain has been associated with innovative solutions to challenges of modern manufacturing, namely dynamic changing of product catalog, distribution of ...
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During the last decade, the Collaborative Manufacturing research domain has been associated with innovative solutions to challenges of modern manufacturing, namely dynamic changing of product catalog, distribution of resources, unexpected disturbances or heterogeneous manufacturing environments. They refer to interdisciplinary results covering all the production perspectives from organizational level - decentralization and autonomy, structural level - reconfigurable systems, and communication level - interoperability. This paper makes an assessment of the most interesting achievements on the collaborative manufacturing, based on the IMS2020 project roadmap key research areas, presented on three emerging approaches: holonic organization for mechatronic control; agent-based implementation for distributed intelligent control; service-oriented communication for coordination, cooperation and collaboration. Some details about the role of intelligent products/resources are explicitly presented. Finally, some conclusions on the state of art in the domain are inferred and some future research challenges are identified.
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