Analysis and Design of Manipulators With Decoupled and Configuration-Invariant Inertia Tensors Using Remote Actuation

1992 ◽  
Vol 114 (2) ◽  
pp. 204-212 ◽  
Author(s):  
K. Youcef-Toumi
Keyword(s):  
High Speed ◽  
Dynamic Properties ◽  
Sufficient Conditions ◽  
Kinematic Chain ◽  
Degree Of Freedom ◽  
Direct Drive ◽  
Analysis And Design ◽  
Remote Actuation ◽  
Three Degree Of Freedom ◽  
Necessary And Sufficient

The dynamics of manipulators with diagonal and/or constant inertia tensors are described by simple differential equations. This feature greatly simplifies the control of high speed manipulators. This paper presents design methods, which incorporate selection of arm structure and link inertial properties, to achieve simplified manipulator dynamics. First the concept of remote actuation is described. A model is then developed in order to analyze the effects of remote actuation on the manipulator kinematics and dynamics. The modeling is based on Kane’s partial rates along with a set notation to concisely express the system’s dynamics. Second, necessary and sufficient conditions for achieving such dynamic properties for open and closed kinematic chain linkages are derived. These techniques are then applied in the design of three degree-of-freedom planar manipulator and the three degree-of-freedom spatial M. I. T direct-drive manipulator. The mass distribution conditions for which the arm inertia tensors are diagonal and configuration-invariant are derived. The resultant dynamic equations of these manipulators are shown to be very simple.

Coupled Stability of Multiport Systems—Theory and Experiments

1994 ◽  
Vol 116 (3) ◽  
pp. 419-428 ◽  
Author(s):  
J. E. Colgate
Keyword(s):  
Stability Property ◽  
Force Feedback ◽  
Linear Time ◽  
Experimental Studies ◽  
Sufficient Conditions ◽  
Direct Drive ◽  
Property A ◽  
Linear Time Invariant ◽  
The Stability ◽  
Necessary And Sufficient

This paper presents both theoretical and experimental studies of the stability of dynamic interaction between a feedback controlled manipulator and a passive environment. Necessary and sufficient conditions for “coupled stability”—the stability of a linear, time-invariant n-port (e.g., a robot, linearized about an operating point) coupled to a passive, but otherwise arbitrary, environment—are presented. The problem of assessing coupled stability for a physical system (continuous time) with a discrete time controller is then addressed. It is demonstrated that such a system may exhibit the coupled stability property; however, analytical, or even inexpensive numerical conditions are difficult to obtain. Therefore, an approximate condition, based on easily computed multivariable Nyquist plots, is developed. This condition is used to analyze two controllers implemented on a two-link, direct drive robot. An impedance controller demonstrates that a feedback controlled manipulator may satisfy the coupled stability property. A LQG/LTR controller illustrates specific consequences of failure to meet the coupled stability criterion; it also illustrates how coupled instability may arise in the absence of force feedback. Two experimental procedures—measurement of endpoint admittance and interaction with springs and masses—are introduced and used to evaluate the above controllers. Theoretical and experimental results are compared.

Design of an Anthropomorphic Upper Extremity Prosthesis

2006 ◽  
Author(s):  
Kevin B. Fite ◽  
Keith W. Wait ◽  
Thomas J. Withrow ◽  
Michael Goldfarb
Keyword(s):  
Degree Of Freedom ◽  
Skeletal Structure ◽  
Direct Drive ◽  
Gas Generator ◽  
Dexterous Manipulation ◽  
Pneumatic Actuators ◽  
Position Sensing ◽  
Human Arm ◽  
Normal Human ◽  
Three Degree Of Freedom

This paper describes the design of a 21 degree-of-freedom, nine degree-of-actuation, gas-actuated arm prosthesis for transhumeral amputees. The arm incorporates a direct-drive elbow and three degree-of-freedom wrist, in addition to a 17 degree-of-freedom underactuated hand effected by five actuators. The anthropomorphic device includes full position and force sensing capability for each actuated degree of freedom and integrates a monopropellant-powered gas generator to provide on-board power for untethered operation. Design considerations addressed in this paper include the sizing of pneumatic actuators based on the requisite output energy at each joint; the development of small low-power servovalves for use with hot/cold gases; the design of compact joints with integrated position sensing; and the packaging of the actuators, on-board power, and skeletal structure within the volumetric envelope of a normal human forearm and elbow. The resulting arm prototype is intended to approach the dexterous manipulation capabilities of its anatomical counterpart while delivering approximately 50% of the force and power output of an average human arm.

Analysis and Design of Fixed–Fixed Bistable Arch-Profiles Using a Bilateral Relationship

2019 ◽  
Vol 11 (3) ◽  
Author(s):  
Safvan Palathingal ◽  
G. K. Ananthasuresh
Keyword(s):  
Boundary Conditions ◽  
Closed Form ◽  
Sufficient Conditions ◽  
Necessary And Sufficient Conditions ◽  
Single Variable ◽  
Fixed Boundary ◽  
Analysis And Design ◽  
Bilateral Relationship ◽  
Variable Equation ◽  
Necessary And Sufficient

Arch-profiles of bistable arches, in their two force-free equilibrium states, are related to each other. This bilateral relationship is derived for arches with fixed–fixed boundary conditions in two forms: a nonlinear single-variable equation for analysis and a closed-form analytical expression for design. Some symmetrical features of shape as well as necessary and sufficient conditions for bistability are presented as corollaries. Analysis and design of arch-profiles using the bilateral relationship are illustrated through examples.

Control System Design for AC-DC Three-Degree-of-Freedom Hybrid Magnetic Bearing

2012 ◽  
Vol 150 ◽  
pp. 144-147 ◽  
Author(s):  
Wei Yu Zhang ◽  
Ying Ruan ◽  
Xiao Yan Diao ◽  
Huang Qiu Zhu
Keyword(s):  
Control System ◽  
System Design ◽  
High Speed ◽  
Manufacturing Industry ◽  
Block Diagram ◽  
Low Cost ◽  
Magnetic Bearing ◽  
Degree Of Freedom ◽  
Control System Design ◽  
Three Degree Of Freedom

To fulfil the objective of high speed, high precision and intelligence in the modern equipment and advanced manufacturing industry, the magnetic bearing is requested to have small volume, low cost and low consumption. In this paper, an AC-DC three-degree-of-freedom hybrid magnetic bearing (AC-DC-3DOF-HMB) is studied, which integrates radial bearing and axial bearing in one of the magnetic bearing. The configuration and principle of AC-DC-3DOF-HMB are expounded, and the mathematical models of suspension forces are given. Then based on the function block diagram of AC-DC-3DOF-HMB control system, its hardware and software configuration are designed. The experiment results show that the rotor can be suspended stably with three degrees of freedom and has a good performance in anti- interference, and the feasibility of the control system design can be verified.

Motion control of a two-axis linear motor-driven stage in the micro-milling process

2016 ◽  
Vol 232 (1) ◽  
pp. 65-76
Author(s):  
Mohammad S Heydarzadeh ◽  
Seyed M Rezaei ◽  
Noor A Mardi ◽  
Ali Kamali E
Keyword(s):  
Kalman Filter ◽  
High Speed ◽  
Linear Motor ◽  
Degree Of Freedom ◽  
Micro Milling ◽  
Proportional Integral Derivative ◽  
Direct Drive ◽  
Proportional Integral Derivative Controller ◽  
Proportional Integral ◽  
Two Degree Of Freedom

The application of linear motor-driven stages as the feed drivers of CNC micro milling machine tools is growing. In addition to employ high speed and high precision equipment such as linear motor-driven stages, the precision of the machined contours is highly dependent on the capabilities of the servo controllers. In this paper, the design of a precise controller for a two-axis LMDS has been investigated for micro-milling applications. In such feed drives, disturbances such as friction, force ripples, and machining forces have adverse effects on the workpiece positioning precision due to the direct drive concept behind them. Therefore, in order to have an acceptable transient response and disturbance rejection properties, a two-degree-of-freedom proportional–integral–derivative controller was employed for each axis. To design this controller, the zero-placement method was used. To compensate disturbances and machining contour errors, the utilization of Kalman filter observers, neural networks, cross-coupled controllers, and different integration of them were studied. The controllers were experimentally examined for circular motions. An integrated controller consisted of a Kalman filter disturbance observer, a cross-coupled controller, and a well-designed two-degree-of-freedom proportional–integral–derivative controller resulted in a high contouring and tracking precision. The controller could also reduce the spikes caused by the friction at the motion reversal points such as the quadrants in circle trajectories.

Maxwell–Voigt and Maxwell Ladder Models for Multi-Degree-of-Freedom Elastomeric Isolation Systems

2015 ◽  
Vol 137 (2) ◽  
Author(s):  
Sudhir Kaul
Keyword(s):  
Degree Of Freedom ◽  
Isolation System ◽  
Practical Applications ◽  
Geometrical Properties ◽  
Analysis And Design ◽  
Proposed Model ◽  
Elastomeric Isolator ◽  
Isolation Systems ◽  
Three Degree Of Freedom ◽  
Ladder Models

This paper presents a model for an elastomeric isolation system consisting of a three degree-of-freedom (DOF) rigid body assembled to a frame through multiple isolators. Each elastomeric isolator is either represented by a Maxwell–Voigt (MV) model consisting of two Maxwell elements or by a Maxwell ladder (ML) model consisting of three Maxwell elements. The MV models and the ML models are characterized by using experimental data that are collected at multiple excitation frequencies. The characterized models are evaluated and used to simulate the performance of the isolation system. The models developed in this paper are capable of representing frequency-dependent behavior that is exhibited by elastomeric isolators and the overall isolation system. Furthermore, the proposed model is capable of directly associating the behavior of the isolation system with physical and geometrical properties of each isolator. The proposed model is expected to be a useful tool for the analysis and design optimization of elastomeric isolation systems. Most of the isolation systems in practical applications exhibit multiple DOF, this model will be particularly useful in such applications since it does not constrain motion to translation only. This is a shortcoming of the models in the current literature that the proposed model attempts to overcome.

Consensus and Consensualization of High-Order Swarm Systems With Time Delays and External Disturbances

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Jianxiang Xi ◽  
Zongying Shi ◽  
Yisheng Zhong
Keyword(s):  
Sufficient Conditions ◽  
Linear Matrix ◽  
Time Varying ◽  
External Disturbances ◽  
Consensus Function ◽  
Design Problems ◽  
Consensus Analysis ◽  
Analysis And Design ◽  
Time Varying Delay ◽  
Necessary And Sufficient

By using dynamic output feedback consensus protocols, consensus analysis, and design, problems for swarm systems with external disturbances and time-varying delays are dealt with. First, two subspaces, namely, a consensus subspace and a complement consensus subspace, are defined. Based on the state projection onto the two subspaces, L2-consensus and L2-consensualization problems are introduced. Then, a necessary and sufficient condition for consensus is presented and an explicit expression of the consensus function is given. Especially, it is shown that the time-varying delay does not influence the consensus function. Finally, in terms of linear matrix inequalities, sufficient conditions for L2-consensus and L2-consensualization are presented, respectively, which possess less calculation complexity, since they are independent of the number of agents, and numerical simulations are shown to demonstrate theoretical results.

Dynamic Analysis of High-Speed Three-Degree-of-Freedom Electromagnetic Actuator for Image Stabilization

2017 ◽  
Vol 53 (11) ◽  
pp. 1-4 ◽  
Author(s):  
Akira Heya ◽  
Katsuhiro Hirata ◽  
Noboru Niguchi ◽  
Takamichi Yoshimoto ◽  
Tomohiro Ota
Keyword(s):  
Dynamic Analysis ◽  
High Speed ◽  
Degree Of Freedom ◽  
Electromagnetic Actuator ◽  
Image Stabilization ◽  
Three Degree Of Freedom

scholarly journals Study on contact angle of double-decker bearing with consider of centrifugal expansion

2021 ◽  
Vol 231 ◽  
pp. 03005
Author(s):  
Jing Hu ◽  
XiaoLi Qiao ◽  
QiongYing Lv ◽  
XinMing Zhang ◽  
JiuTong Zhai ◽  
...  
Keyword(s):  
Contact Angle ◽  
Numerical Calculation ◽  
Numerical Analysis ◽  
Potential Application ◽  
High Speed ◽  
Dynamic Properties ◽  
Object A ◽  
Analysis And Design ◽  
Double Decker ◽  
Middle Ring

Improving the precision of numerical calculation of double-decker bearing is the basis of exploring its potential application value. This paper takes double-decker bearing as the research object, a modified quasi-statics model of double-decker bearing was established by considering the influence of the centrifugal expansion of the inner and middle ring of double-decker bearing at high speed and solve it with soft of Matlab. The influence of centrifugal expansion on the contact angle of the double-decker bearing was analyzed. The results show that the centrifugal expansion caused by the inner ring and middle ring under high speed can not be ignored, and the centrifugal expansion has a greater influence on the contact angle of inner bearing than that of outer bearing. The influence of centrifugal expansion on the dynamic properties of different materials is different, and the change of contact angle caused by ceramic as the inner ring and middle ring is greater than that of steel. It provides the basis for more accurate numerical analysis and design of the double-decker bearing.

Optimal Guaranteed Cost Control of Four-Wheel Steering Vehicle with Three Degree-of-Freedom

2014 ◽  
Vol 574 ◽  
pp. 557-563 ◽  
Author(s):  
Xin Quan Yin ◽  
Ya Ping Zhang
Keyword(s):  
High Speed ◽  
Cost Control ◽  
Guaranteed Cost Control ◽  
Stability Control ◽  
Degree Of Freedom ◽  
Lateral Acceleration ◽  
Slip Angle ◽  
Linear Matrix ◽  
Guaranteed Cost ◽  
Three Degree Of Freedom

A nonlinear model of 4WS vehicle with three degree-of-freedom is established, Considering the uncertain characteristic of the tire lateral stiffness, an guaranteed cost control scheme was proposed for vehicle stability control, the optimal guaranteed cost control laws is derived in terms of linear matrix inequalities (LMIs). The simulation results show that transient response amplitude of the yaw rate , center side-slip angle and lateral acceleration can be decreased greatly, a good steady-state response can be achieved at a high speed, which improves the driving safety and handling stability.

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