scholarly journals Actuation and Control Strategies for Miniature Robotic Surgical Systems

2004 ◽  
Vol 127 (4) ◽  
pp. 537-549 ◽  
Author(s):  
Jason M. Stevens ◽  
Gregory D. Buckner
Keyword(s):  
Minimally Invasive ◽  
Control Strategies ◽  
Three Dimensional ◽  
Robotic Systems ◽  
End Effector ◽  
Cardiac Procedures ◽  
Recovery Times ◽  
Dynamics And Control ◽  
On Line ◽  
And Control

During the past 20years, tremendous advancements have been made in the fields of minimally invasive surgery (MIS) and minimally invasive, robotically assisted (MIRA) cardiac surgery. Benefits from MIS include reduced pain and trauma, reduced risks of post-operative complications, shorter recovery times, and more aesthetically pleasing results. MIRA approaches have extended the capabilities of MIS by introducing three-dimensional vision, eliminating hand tremors, and enabling the precise articulation of smaller instruments. These advancements come with their own drawbacks, however. Robotic systems used in MIRA cardiac procedures are large, costly, and do not offer the miniaturized articulation necessary to facilitate tremendous advancements in MIS. This paper demonstrates that miniature actuation can overcome some of the limitations of current robotic systems by providing accurate, repeatable control of a small end effector. A 10× model of a two link surgical manipulator is developed, using antagonistic shape memory alloy wires as actuators, to simulate motions of a surgical end-effector. Artificial neural networks are used in conjunction with real-time visual feedback to “learn” the inverse system dynamics and control the manipulator endpoint trajectory. Experimental results are presented for indirect, on-line learning and control. Manipulator tip trajectories are shown to be accurate and repeatable to within 0.5mm. These results confirm that SMAs can be effective actuators for miniature surgical robotic systems, and that intelligent control can be used to accurately control the trajectory of these systems.

The Current Situation and Progress of 4-DOF Parallel Robot

2010 ◽  
Vol 37-38 ◽  
pp. 1433-1436 ◽  
Author(s):  
Yan Qing Wang ◽  
Gao Yan Zhong ◽  
Yong Biao Chang ◽  
Guo Xin Liu
Keyword(s):  
Unsolved Problem ◽  
Control Strategies ◽  
Parallel Robot ◽  
Current Situation ◽  
Research Trend ◽  
Key Technologies ◽  
Dynamics And Control ◽  
And Control

In this paper, the existing research and key technologies of 4-DOF parallel robot are reviewed, i.e., mechanism, kinematics, singularity, workspace, dexterity, dynamics and control. Most of them are focused on mechanism and kinematics. The study in dynamics and control is relatively rare and not mature in practice, especially in how to optimize the control strategies to improve its performance. Finally, the research trend and unsolved problem of 4-DOF parallel robot is described.

scholarly journals Stochastic epidemic metapopulation models on networks: SIS dynamics and control strategies

2018 ◽  
Vol 449 ◽  
pp. 35-52 ◽  
Author(s):  
Andrew L. Krause ◽  
Lawrence Kurowski ◽  
Kamran Yawar ◽  
Robert A. Van Gorder
Keyword(s):  
Control Strategies ◽  
Stochastic Epidemic ◽  
Dynamics And Control ◽  
Metapopulation Models ◽  
And Control

Dynamics and Control of Robotic Systems Worn by Humans

1991 ◽  
Vol 113 (3) ◽  
pp. 379-387 ◽  
Author(s):  
H. Kazerooni ◽  
S. L. Mahoney
Keyword(s):  
Material Handling ◽  
Robotic Systems ◽  
Control Technique ◽  
Load Force ◽  
Two Dimensional ◽  
Direct Drive ◽  
Human Arm ◽  
Dynamics And Control ◽  
Physical Interfaces ◽  
And Control

This article describes the dynamics, control, and stability of extenders, robotic systems worn by humans for material handling tasks. Extenders are defined as robot manipulators which extend (i.e., increase) the strength of the human arm in load maneuvering tasks, while the human maintains control of the task. Part of the extender motion is caused by physical power from the human; the rest of the extender motion results from force signals measured at the physical interfaces between the human and the extender, and the load and the extender. Therefore, the human wearing the extender exchanges both power and information signals with the extender. The control technique described here lets the designer define an arbitrary relationship between the human force and the load force. A set of experiments on a two-dimensional non-direct-drive extender were done to verify the control theory.

A Comparative, Experimental Study of Model Suitability to Describe Vehicle Rollover Dynamics for Control Design

2005 ◽  
Author(s):  
John T. Cameron ◽  
Sean Brennan
Keyword(s):  
Experimental Validation ◽  
Controller Design ◽  
Experimental Testing ◽  
Control Strategies ◽  
Control Design ◽  
Experimental Results ◽  
Dynamics And Control ◽  
Vehicle Rollover ◽  
And Control ◽  
Future Work

This work presents results of an initial investigation into models and control strategies suitable to prevent vehicle rollover due to untripped driving maneuvers. Outside of industry, the study of vehicle rollover inclusive of both experimental validation and practical controller design is limited. The researcher interested in initiating study on rollover dynamics and control is left with the challenging task of identifying suitable vehicle models from the literature, comparing these models with experimental results, and determining suitable parameters for the models. This work addresses these issues via experimental testing of published models. Parameter estimation data based on model fits is presented, with commentary given on the validity of different methods. Experimental results are then presented and compared to the output predicted by the various models in both the time and frequency domain in order to provide a foundation for future work.

scholarly journals Quadrotor Unmanned Aerial Vehicles: Visual Interface for Simulation and Control Development

2021 ◽  
Author(s):  
Manuel A. Rendón
Keyword(s):  
Control Strategies ◽  
Basin Of Attraction ◽  
Three Dimensional ◽  
Research Area ◽  
Visual Evaluation ◽  
Development Platform ◽  
Planning Algorithm ◽  
Thrust Vector ◽  
And Control ◽  
Visual Interface

Quadrotor control is an exciting research area. Despite last years developments, some aspects demand a deeper analysis: How a quadrotor operates in challenging trajectories, how to define trajectory limits, or how changing physical characteristics of the device affects the performance. A visual interface development platform is a valuable tool to support this effort, and one of these tools is briefly described in this Chapter. The quadrotor model uses Newton-Euler equations with Euler angles, and considers the effect of air drag and propellers’ speed dynamics, as well as measurement noise and limits for propeller speeds. The tool is able to test any device just by setting a few parameters. A three-dimensional optimal trajectory defined by a set of waypoints and corresponding times, is calculated with the help of a Minimum Snap Trajectory planning algorithm. Small Angle Control, Desired Thrust Vector (DTV) Control and Geometric Tracking Control are the available strategies in the tool for quadrotor attitude and trajectory following control. The control gains are calculated using Particle Swarm Optimization. Root Mean Square (RMS) error and Basin of Attraction are employed for validation. The tool allows to choose the control strategy by visual evaluation on a graphical user interface (GUI), or analyzing the numerical results. The tool is modular and open to other control strategies, and is available in GitHub.

scholarly journals Mathematical modelling and phylodynamics for the study of dog rabies dynamics and control: A scoping review

2021 ◽  
Vol 15 (5) ◽  
pp. e0009449
Author(s):  
Maylis Layan ◽  
Simon Dellicour ◽  
Guy Baele ◽  
Simon Cauchemez ◽  
Hervé Bourhy
Keyword(s):  
Mathematical Modelling ◽  
Mathematical Models ◽  
Scoping Review ◽  
Control Strategies ◽  
Domestic Dog ◽  
Interdisciplinary Approaches ◽  
Dynamics And Control ◽  
And Control ◽  
The Impact

Background Rabies is a fatal yet vaccine-preventable disease. In the last two decades, domestic dog populations have been shown to constitute the predominant reservoir of rabies in developing countries, causing 99% of human rabies cases. Despite substantial control efforts, dog rabies is still widely endemic and is spreading across previously rabies-free areas. Developing a detailed understanding of dog rabies dynamics and the impact of vaccination is essential to optimize existing control strategies and developing new ones. In this scoping review, we aimed at disentangling the respective contributions of mathematical models and phylodynamic approaches to advancing the understanding of rabies dynamics and control in domestic dog populations. We also addressed the methodological limitations of both approaches and the remaining issues related to studying rabies spread and how this could be applied to rabies control. Methodology/principal findings We reviewed how mathematical modelling of disease dynamics and phylodynamics have been developed and used to characterize dog rabies dynamics and control. Through a detailed search of the PubMed, Web of Science, and Scopus databases, we identified a total of n = 59 relevant studies using mathematical models (n = 30), phylodynamic inference (n = 22) and interdisciplinary approaches (n = 7). We found that despite often relying on scarce rabies epidemiological data, mathematical models investigated multiple aspects of rabies dynamics and control. These models confirmed the overwhelming efficacy of massive dog vaccination campaigns in all settings and unraveled the role of dog population structure and frequent introductions in dog rabies maintenance. Phylodynamic approaches successfully disentangled the evolutionary and environmental determinants of rabies dispersal and consistently reported support for the role of reintroduction events and human-mediated transportation over long distances in the maintenance of rabies in endemic areas. Potential biases in data collection still need to be properly accounted for in most of these analyses. Finally, interdisciplinary studies were determined to provide the most comprehensive assessments through hypothesis generation and testing. They also represent new avenues, especially concerning the reconstruction of local transmission chains or clusters through data integration. Conclusions/significance Despite advances in rabies knowledge, substantial uncertainty remains regarding the mechanisms of local spread, the role of wildlife in dog rabies maintenance, and the impact of community behavior on the efficacy of control strategies including vaccination of dogs. Future integrative approaches that use phylodynamic analyses and mechanistic models within a single framework could take full advantage of not only viral sequences but also additional epidemiological information as well as dog ecology data to refine our understanding of rabies spread and control. This would represent a significant improvement on past studies and a promising opportunity for canine rabies research in the frame of the One Health concept that aims to achieve better public health outcomes through cross-sector collaboration.

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