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Full-Text Articles in Mechanical Engineering

A Framework For Stable Robot-Environment Interaction Based On The Generalized Scattering Transformation, Kanstantsin Pachkouski Nov 2022

A Framework For Stable Robot-Environment Interaction Based On The Generalized Scattering Transformation, Kanstantsin Pachkouski

Electronic Thesis and Dissertation Repository

This thesis deals with development and experimental evaluation of control algorithms for stabilization of robot-environment interaction based on the conic systems formalism and scattering transformation techniques. A framework for stable robot-environment interaction is presented and evaluated on a real physical system. The proposed algorithm fundamentally generalizes the conventional passivity-based approaches to the coupled stability problem. In particular, it allows for stabilization of not necessarily passive robot-environment interaction. The framework is based on the recently developed non-planar conic systems formalism and generalized scattering-based stabilization methods. A comprehensive theoretical background on the scattering transformation techniques, planar and non-planar conic systems is presented. …


Hierarchical Control Of Complex Manufacturing Processes, Hesam Zomorodi Moghadam Jan 2016

Hierarchical Control Of Complex Manufacturing Processes, Hesam Zomorodi Moghadam

Doctoral Dissertations

"The need for changing the control objective during the process has been reported in many systems in manufacturing, robotics, etc. However, not many works have been devoted to systematically investigating the proper strategies for these types of problems. In this dissertation, two approaches to such problems have been suggested for fast varying systems. The first approach, addresses problems where some of the objectives are statically related to the states of the systems. Hierarchical Optimal Control was proposed to simplify the nonlinearity caused by adding the statically related objectives into control problem. The proposed method was implemented for contour-position control of …


Modified Robust External Force Control With Disturbance Rejection With Application To Piezoelectric Actuators Jan 2015

Modified Robust External Force Control With Disturbance Rejection With Application To Piezoelectric Actuators

Faculty of Engineering University of Malaya

In micromanipulation applications, controlling the force exerted on the object is of great importance. In such cases, any uncontrolled forces may damage the object or cause system failure. However, the presence of disturbances such as impedance uncertainties and hysteresis can strongly degrade force control performance and even lead to instability. Therefore, accurate force control when internal and external disturbances occur is a significant challenge. Conventional control methods usually have a number of restrictive conditions especially on the disturbance bounds. To rectify those issues, a modified robust disturbance rejection-based force control approach is proposed in this paper. For this purpose, an …


Multi-Muscle Fes Force Control Of The Human Arm For Arbitrary Goals, Eric M. Schearer, Yu-Wei Liao, Eric J. Perreault, Matthew C. Tresch, William D. Memberg, Robert F. Kirsch, Kevin M. Lynch May 2014

Multi-Muscle Fes Force Control Of The Human Arm For Arbitrary Goals, Eric M. Schearer, Yu-Wei Liao, Eric J. Perreault, Matthew C. Tresch, William D. Memberg, Robert F. Kirsch, Kevin M. Lynch

Mechanical Engineering Faculty Publications

We present a method for controlling a neuroprosthesis for a paralyzed human arm using functional electrical stimulation (FES) and characterize the errors of the controller. The subject has surgically implanted electrodes for stimulating muscles in her shoulder and arm. Using input/output data, a model mapping muscle stimulations to isometric endpoint forces measured at the subject’s hand was identified. We inverted the model of this redundant and coupled multiple-input multiple-output system by minimizing muscle activations and used this inverse for feedforward control. The magnitude of the total root mean square error over a grid in the volume of achievable isometric endpoint …


Integrated Servomechanism And Process Control For Machining Processes, Yan Tang Jan 2009

Integrated Servomechanism And Process Control For Machining Processes, Yan Tang

Electronic Theses and Dissertations

In this research, the integration of the servomechanism control and process control for machining processes has been studied. As enabling strategies for next generation quality control, process monitoring and open architecture machine tools will be implemented on production floor. This trend brings a new method to implement control algorithm in machining processes. Instead of using separate modules for servomechanism control and process control individually, the integrated controller is proposed in this research to simultaneously achieve goals in servomechanism level and the process level. This research is motivated by the benefits brought by the integration of servomechanism control and process control. …


Admittance Selection Conditions For Frictionless Force-Guided Assembly Of Polyhedral Parts In Two Single-Point Principal Contacts, Shuguang Huang, Joseph M. Schimmels Apr 2008

Admittance Selection Conditions For Frictionless Force-Guided Assembly Of Polyhedral Parts In Two Single-Point Principal Contacts, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

The admittance of a manipulator can be used to improve robotic assembly. If properly selected, the admittance will regulate a contact force and use it to guide the parts to proper positioning. In previous work, procedures for selecting the appropriate admittance for single principal contact (PC) cases were identified. This paper extends this research for some of the two PC cases-those for which each contact occurs at a single point. The conditions obtained ensure that the motion that results from frictionless contact always instantaneously reduces part misalignment. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reducing conditions …


Admittance Selection For Force-Guided Assembly Of Polygonal Parts Despite Friction, Shuguang Huang, Joseph M. Schimmels Oct 2004

Admittance Selection For Force-Guided Assembly Of Polygonal Parts Despite Friction, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

An important issue in the development of force guidance assembly strategies is the specification of an appropriate admittance control law. This paper identifies conditions to be satisfied when selecting the appropriate admittance to achieve force-guided assembly of polygonal parts for multipoint contact with friction. These conditions restrict the admittance behavior for each of the various one-point and two-point contact cases and ensure that the motion that results from contact reduces part misalignment for each case. We show that, for bounded friction and part misalignments, if the identified conditions are satisfied for a finite number of contact configurations and friction coefficients, …


Admittance Selection For Force-Guided Assembly Of Polyhedral Parts In Single-Point Contact, Shuguang Huang, Joseph M. Schimmels Jul 2004

Admittance Selection For Force-Guided Assembly Of Polyhedral Parts In Single-Point Contact, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

The selection of the proper admittance is important in achieving force-guided assembly. This paper identifies procedures for selecting the appropriate spatial admittance to achieve reliable force-guided assembly of polyhedral parts for single-point frictionless contact cases. Sets of conditions that are imposed on the admittance matrix for different types of single-point contact are presented. These conditions ensure that the motion that results from contact reduces part misalignment in the selected contact state. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reduction conditions at a finite number of contact configurations, then the admittance also satisfy the conditions at all …


Sufficient Conditions For Admittance To Ensure Planar Force-Assembly In Multi-Point Frictionless Contact, Shuguang Huang, Joseph M. Schimmels Sep 2003

Sufficient Conditions For Admittance To Ensure Planar Force-Assembly In Multi-Point Frictionless Contact, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

An important issue in the development of force guidance assembly strategies is the specification of an appropriate admittance control law. This paper identifies procedures for selecting the appropriate admittance to achieve reliable planar force-guided assembly for multi-point contact cases. Conditions that restrict the admittance behavior for each of the various types of two-point contact are presented. These conditions ensure that the motion that results from contact reduces part misalignment for each case. We show that, for bounded misalignments, if the conditions are satisfied for a finite number of contact configurations, the conditions ensure that force guidance is achieved for all …


Admittance Selection For Planar Force-Guided Assembly For Single-Point Contact With Friction, Shuguang Huang, Joseph M. Schimmels Sep 2003

Admittance Selection For Planar Force-Guided Assembly For Single-Point Contact With Friction, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

This paper identifies procedures for selecting the appropriate admittance to achieve reliable planar force-guided assembly for single-point frictional contact cases. A set of conditions that are imposed on the admittance matrix is presented. These conditions ensure that the motion that results from contact reduces part misalignment. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reduction conditions at a finite number of contact configurations and a given coefficient of friction /spl mu//sub M/) then the admittance will also ensure that the conditions are satisfied at all intermediate configurations for all coefficients less than /spl mu//sub M/.


Sufficient Conditions Used In Admittance Selection For Force-Guided Assembly Of Polygonal Parts, Shuguang Huang, Joseph M. Schimmels Aug 2003

Sufficient Conditions Used In Admittance Selection For Force-Guided Assembly Of Polygonal Parts, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

Admittance control approaches show significant promise in providing reliable force-guided assembly. An important issue in the development of these approaches is the specification of an appropriate admittance control law. This paper identifies procedures for selecting the appropriate admittance to achieve reliable force-guided assembly of planar polyhedral parts for single-point contact cases. A set of conditions that are imposed on the admittance matrix is presented. These conditions ensure that the motion that results from contact reduces part misalignment. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reduction conditions at a finite number of contact configurations, then the admittance …


Sufficient Conditions Used In Admittance Selection For Planar Force-Guided Assembly, Shuguang Huang, Joseph M. Schimmels May 2002

Sufficient Conditions Used In Admittance Selection For Planar Force-Guided Assembly, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

Admittance control approaches show significant promise in providing reliable force-guided assembly. An important issue in the development of these approaches is the specification of an appropriate admittance control law. This paper identifies procedures for selecting the appropriate admittance to achieve reliable planar force-guided assembly for single-point contact cases. A set of conditions that are imposed on the admittance matrix is presented. These conditions ensure that the motion that results from contact reduces part misalignment. We show that for bounded misalignment, if the conditions are satisfied for a finite number of contact configurations, the system ensures that force guidance is achieved …