Differential-Difference Equations. By Richard Bellman and Kenneth L. Cooke. Pp. xvi, 465. 1963. (Academic Press)

A scheme is developed for classifying the types of motion perceived by a humanlike robot. It is assumed that the robot receives visual images of the scene using a perspective system model. Equations, theorems, concepts, clues, etc., relating the objects, their positions, and their motion to their images on the focal plane are presented. >

http://ieeexplore.ieee.org/iel2/815/3148/00100651.pdf

Robot vision

[서평]「The Unified Modeling Language User Guide」

Summary) The abstract should follow the structure of the article (relevance, degree of exploration of the problem, the goal, the main results, conclusion) and characterize the theoretical and practical significance of the study results. The abstract should not contain wording echoing the title, cumbersome grammatical structures and abbreviations. The text should be written in scientific style. The volume of abstracts (summaries) depends on the content of the article, but should not be less than 250 words. All abbreviations must be disclosed in the summary (in spite of the fact that they will be disclosed in the main text of the article), references to the numbers of publications from reference list should not be made. The sentences of the abstract should constitute an integral text, which can be made by use of the words “consequently”, “for example”, “as a result”. Avoid the use of unnecessary introductory phrases (eg, “the author of the article considers...”, “The article presents...” and so on.)

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Ministry of Education and Science of the Russian Federation

Dynamic analysis of flexible manipulators, a literature review

Robust tuning of PID regulators based on step-response identification

A computationally efficient recursive model of a flexible manipulator with motors at the joints is described in this paper. The model adopts a mixed Eulerian and Lagrangian formulation of the equations of a flexible body and exploits the chained structure of the equations for a serial manipulator. The dynamic effects of the motors at the joints, including gyroscopic terms, are fully taken into account. Symbolic manipulation is used in a newly developed package, whose performance in detailed reproduction of the dynamic effects due to the interplay between the motors and the flexible links is assessed through simulation. A comparison between the complete model and a simplified one, where the motors are considered as simple inertias rotating around their own axis, has been carried out, using both a time domain analysis and a frequency domain analysis, in order to show the relevance of gyroscopic effects in modelling flexible robots.

Modelling Flexible Manipulators With Motors at the Joints

In this work, we propose a constraint-based algorithm for combined trajectory generation and kinematic control for robotic manipulators. The main feature of the algorithm is to ease robot programming, shifting from an imperative paradigm, in which task constraints are semantically and uniquely mapped into a suitable end-effector velocity profile, towards a declarative motion programming, where such constraints are turned by the controller into motion commands only at run-time: The system embeds the capability of handling real-time events, such as updated sensor readings, with reduced pre-programmed control logics. An experimental case study based on a 7-DOF robot demonstrates the effectiveness of the approach.

Reactive motion planning and control for compliant and constraint-based task execution

In this paper, a controller based on constrained optimization for tracking problems in mobile manipulation is presented. A Model Predictive Control problem is set and solved online, allowing to deal with dynamic scenarios and unforeseen events. Besides acceleration, velocity and position constraints, collision avoidance constraints for the mobile base and the arm and Field-of-View constraints have been enforced and extended over the prediction horizon. Navigation performance has been improved by including an additional goal, derived from the classical vortex field approach, to the MPC problem. An experimental validation on a KUKA youBot mobile manipulator has been carried out, showing the online applicability of the presented approach.

Constraint-based Model Predictive Control for holonomic mobile manipulators

The traditional control architecture adopted for asynchronous motors consists of a cascaded control with an inner current loop, based on field-oriented control and an external velocity loop. In the majority of industrial applications this architecture makes use of velocity and flux observers, both fed by a position measurement that is often characterized by low resolution. This paper investigates the effects of the velocity/flux estimation error on the performance of the current/velocity regulation. A methodology, based on a linearized model of the motion control system, is introduced to quantify the perturbations caused by these estimators. Large discrepancies between the stator currents and their estimates, as well as distortion of the mechanical transfer function are explained in the light of these simplified models. Guidelines to improve the design of the current/velocity regulators are presented too. An experimental case study demonstrates how these tools can be exploited to analyze the motion control system of a commercial washing machine.

Paolo Rocco

Papers

Robust tuning of PID regulators based on step-response identification

Modelling Flexible Manipulators With Motors at the Joints

Reactive motion planning and control for compliant and constraint-based task execution

Constraint-based Model Predictive Control for holonomic mobile manipulators

Performance Limitations in Field-Oriented Control for Asynchronous Machines With Low Resolution Position Sensing