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Showing papers on "Kinematics published in 1983"


Journal ArticleDOI
TL;DR: This paper presents a joint coordinate system that provides a simple geometric description of the three-dimensional rotational and translational motion between two rigid bodies.
Abstract: The experimental study of joint kinematics in three dimensions requires the description and measurement of six motion components. An important aspect of any method of description is the ease with which it is communicated to those who use the data. This paper presents a joint coordinate system that provides a simple geometric description of the three-dimensional rotational and translational motion between two rigid bodies. The coordinate system is applied to the knee and related to the commonly used clinical terms for knee joint motion. A convenient characteristic of the coordinate system shared by spatial linkages is that large joint displacements are independent of the order in which the component translations and rotations occur.

3,484 citations




Journal ArticleDOI
TL;DR: The fact that the velocity of execution increases with the radius of curvature implies a built-in tendency of the motor control system to keep angular velocity relatively constant and qualifies the Isogony Principle proposed previously.

675 citations


Journal ArticleDOI
TL;DR: In this article, a new method for calculating the acceleration of a robot in response to given actuator forces is described, which is applicable to open-loop kinematic chains containing revolute and prismatic joints.
Abstract: This paper describes a new method for calculating the acceleration of a robot in response to given actuator forces. The method is applicable to open-loop kinematic chains containing revolute and prismatic joints. The algorithm is based on recursive formulas involving quantities called articulated-body inertias, which represent the inertia properties of collections of rigid bodies connected together by joints allowing constrained relative motion between the bodies. A new, matrix-based notation is introduced to represent articulated-body inertias and other spatial quantities. This notation is used to develop the algorithm, and results in a compact representation of the equations. The new algorithm has a computational requirement that varies linearly with the number of joints, and its efficiency is compared with other published algorithms.

590 citations


Book
01 Jan 1983
TL;DR: In this article, the authors present a Vector Analysis Review for the Fundamentals of Engineering Examination Answers to selected problems, including three dimensional kinematics and kinetics of a rigid body.
Abstract: Kinematics of a particle Kinetics of a particle - Force and Acceleration Kinetics of a Particle - Work and Energy Kinetics of a Particle - Impulse and Momentum Review 1 - kinematics and kinetics of a particle Planar Kinematics of a Rigid Body - Force and Acceleration6 Planar Kinetics of a Rigid Body - Work and Energy Planar Kinetics of a Rigid Body - Impulse and Momentum Review 2: planar kinematics and kinetics of a rigid body Three Dimensional Kinematics of a Rigid Body Vibrations. Appendixes: MathematicalExpressions Numerical Methods Vector Analysis Review for the Fundamentals of Engineering Examination Answers to selected problems.

531 citations



Journal ArticleDOI
TL;DR: In this article, a stabilization procedure is developed for controlling the kinematic modes of the four-node, bilinear quadrilateral element when single-point quadrature is used.
Abstract: A stabilization procedure is developed for controlling the kinematic modes of the four-node, bilinear quadrilateral element when single-point quadrature is used. These kinematic modes manifest themselves by spatial oscillations or singularity of the total stiffness. In this stabilization procedure, additional generalized strains are defined which are activated by the kinematic modes; these generalized modes are furthermore not activated by rigid body motions regardless of the shape of the quadrilateral. By using a scaling law developed in an earlier paper, the stabilization parameters are defined so they do not adversely affect the element's performance. Several problems which are subject to kinematic modes are presented to illustrate the performance of this stabilization procedure for linear problems.

265 citations


Journal ArticleDOI
TL;DR: In this paper, the authors consider a general six-joint robot and show that all such robots are limited in their ability to respond in orientation to feedback commands, and also show that it is simple to predict, if not to avoid, these regions of degeneracy in which the manipulator loses a degree of freedom.
Abstract: Robots for use in assembly and other interactive tasks must be able to respond to both forces and velocity com mands within their workspace. By considering a general six-joint robot we show that all such robots are limited in their ability to respond in orientation to feedback commands. We also show that it is simple to predict, if not to avoid, these regions of degeneracy in which the manipulator loses a degree of freedom.

227 citations


Journal ArticleDOI
TL;DR: In this paper, an efficient algorithm for the calculation of the inverse kinematic accelerations for a six-degree-of-freedom manipulator with a spherical wrist was presented.
Abstract: An efficient algorithm is presented for the calculation of the inverse kinematic accelerations for a six-degree-of-freedom manipulator with a spherical wrist. The inverse kinematic calculation is shown to work synergistically with the inverse dynamic calculation, producing kinematic parameters needed in the recursive Newton-Euler dynamics formulation. Additional savings in the dynamic computation are noted for a class of kinematically well-structured manipulators, such as spherical-wrist arms, and for manipulators with simply structured inertial parameters.

137 citations



Journal ArticleDOI
TL;DR: In this paper, the authors describe the design concept of a new robot based on the direct-drive method using rare-earth DC torque motors, where the arm links are directly coupled to the motor rotors.
Abstract: : This paper describes the design concept of a new robot based on the direct-drive method using rare-earth DC torque motors. Because these motors have high torque, light weight and compact size, we can construct robots with far better performance than those presently available. For example, we can eliminate all the transmission mechanism between the motors and their loads, such as reducers and chain belts, and construct a simple mechanism (direct-drive) where the arm links are directly coupled to the motor rotors. This elimination can lead to excellent performance: no backlash, low friction, low inertia, low compliance and high reliability, all of which are suited for high-speed high-precision robots. First we propose a basic configuration of direct-drive robots. Second a general procedure for designing direct-drive robots is shown, and the feasibility of direct drive for robot actuation is discussed in terms of weights and torques of joints. One of the difficulties in designing direct-drive robots is that motors to drive wrist joints are loads for motors to drive elbow joints and they are loads for motors at shoulders. To reduce this increasing series of loads is an essential issue for designing practical robots. We analyze the series of joint mass for a simplified kinematic model of the direct-drive robots, and show how the loads are reduced significantly by using rare-earth motors with light weight and high torque. We also discuss optimum kinematic structures with minimum arm weight. Finally, we describe the direct-drive robotic manipulator (CMU arm) developed at Carnegie-Mellon University, and verify the design theory. (Author)


Book
01 Jan 1983
TL;DR: Tasks and performance of articulated robots, including descriptions of tasks and the performance of tasks, and the choice of the space used in computation are described.
Abstract: 1 Definitions and objectives.- Origin of the word 'robot'.- Robotics today.- What is a robot?.- Classification of robots.- Conclusions.- 2 Structure and specification of articulated robots.- Degrees of freedom of a solid.- Degrees of freedom of a robot.- Position of the vehicle and resulting redundancy of degrees of freedom.- How many degrees of freedom?.- False degrees of freedom.- Architecture of the arm.- Description of articulated mechanical systems.- Conclusions.- 3 Articulated mechanical systems: determination of kinematic elements.- Computation of the orientation of a chain relative to a set bound to an upper segment.- Computation of the orientation of a chain relative to a set bound to a lower segment.- Computation of the position of a point on a chain in relation to an upper segment.- Computation of the position of a point on a chain in relation to a lower segment.- Determination of the velocity vectors of rotation of different segments of a chain relative to a set of coordinate axes.- Determination of the velocity vectors of translation of different segments of a chain relative to a set of coordinate axes.- Conclusions.- 4 Calculation of robot articulation variables.- The absence of a solution.- An infinite number of solutions.- A limited number of solutions.- Practical choice of [Pi(R0), Sj(R0)].- Mechanisms with six degrees of freedom.- Mechanisms with more than six degrees of freedom.- Conclusions.- 5 Positional control of articulated robots.- Reference and starting configurations.- The principles of positional control.- Balanced and initialization configurations.- The problems associated with positional control.- 6 Speed control of articulated robots.- The principles of speed control.- Problems arising from the use of equation (6-16).- Methods of resolving redundant systems.- Conclusions.- 7 Articulated mechanical systems: the dynamic model.- A dynamic model for an open articulated chain of rigid segments, without backlash or friction.- Development of a dynamic equation for a system having three degrees of freedom.- Another type of model: the bond graph.- Difficulties with dynamic models.- A dynamic model of a belt drive.- Conclusions.- 8 Dynamic control of articulated robots.- Problems associated with real time and computation.- Simplification of the equation of the model.- Other methods of dynamic control.- The choice of the space used in computation.- Conclusions.- 9 Learning and trajectory generation.- Methods of recording trajectories.- Manual control used outside of training.- Improved controls.- Trajectory generation.- Conclusions.- 10 Tasks and performance of articulated robots.- Description of tasks.- The performance of articulated robots.- Conclusions.- References.



Journal ArticleDOI
TL;DR: An experimental microcomputer controlled prosthesis is discussed, where knee damping is governed by kinematic signals, picked up from both legs, which was found to be more advantageous than a conventional valve system in significantly reducing hip muscular effort on the prosthetic side.

Journal ArticleDOI
01 Jan 1983
TL;DR: Methods of joint trajectory generation for mechanical manipulators using X-spline and quartic spline functions are presented and an illustrative example is used for comparing these trajectories to other existent polynomial-type trajectories.
Abstract: Methods of joint trajectory generation for mechanical manipulators using X-spline and quartic spline functions are presented. A sequence of Cartesian knots, i.e. positions and orientations of the hand, are selected from the desired Cartesian path. Joint values corresponding to these selected knots are solved from the kinematic equation. Approximate joint paths are constructed by interpolating these joint positions. At any instant, two or more future knots need to be known in advance in order to determine the current joint trajectories. Approximate errors for Cartesian paths are discussed. An illustrative example is used for comparing these trajectories to other existent polynomial-type trajectories.

Proceedings ArticleDOI
01 Jan 1983

Journal ArticleDOI
TL;DR: In this paper, the authors formulated the kinematic interaction of embedded rectangular foundations by the random vibration theory, and discussed the effect by examining field data obtained in earthquakes, and analyzed the effect of the low pass filter on the ground motions.

Journal ArticleDOI
TL;DR: The findings suggest that the task criterion specifies the appropriate information feedback for skill learning in that the information feedback must match the constraints imposed upon response output.

Journal ArticleDOI
TL;DR: In this article, the effects of non-linear kinematics on optimal evasive strategies from a pursuer guided by proportional navigation are investigated in a plane, and the inability to satisfy both principles suggests a three-dimensional manoeuvre perpendicular to the initial collision plane.
Abstract: The effects of non-linear kinematics on optimal evasive strategies from a pursuer guided by proportional navigation are investigated in a plane. Non-linear analysis is mandatory since, for certain values of system parameters and initial conditions, linearized kinematic models are not valid. The investigation discloses two principles of optimal evasion. For long pursuit time, both principles are satisfied and the relatively large miss distance is almost independent of the initial conditions. Short pursuit time does not allow simultaneous satisfaction of both principles, and the two-dimensional optimal compromise results in a reduced miss distance. The inability to satisfy both principles suggests a three-dimensional manoeuvre perpendicular to the initial collision plane.

Journal ArticleDOI
TL;DR: Although there was significant variability in the centers of rotation, there were definite locations related to each load type and the results may be helpful in the clinical interpretation of spinal kinematic studies.

Journal ArticleDOI
TL;DR: In this paper, nonlinear equations of motion for flexible manipulator arms consisting of rotary joints connecting two flexible links are developed, where the link deflection is assumed small so that the link transformation can be composed of summations of assumed link shapes.

Patent
31 May 1983
TL;DR: In this paper, a kinematic system of an industrial robot and a sequential control system of its operating cycle is described, which consists of a vertical spindle supporting a main rotating arm and a forearm fixed to a gripping component.
Abstract: The invention concerns a kinematic system of an industrial robot and a sequential control system of its operating cycle. The robot comprises a vertical spindle supporting a main rotating arm and a forearm fixed to a gripping component. A first vertical transfer jack is provided at the end of the forearm. Arms are mounted via bearings on a loose spindle in a link and can swivel, driven by servo-motors in a horizontal plane so as to form a kinematic system functioning in cylindrical coordinates. The servo-motors are programmed to drive the gripping component through a linear trajectory at the beginning of the cycle. A releasable couping system with memory device is provided for the tool-holder. The controller control system is arranged to ensure the transitory readjustment of each arm to a starting position.

Journal ArticleDOI
TL;DR: This paper discusses the modeling and measurement of anatomical joint motion from a kinematics viewpoint and one, two, three and six degree-of-freedom models for various anatomical joints have appeared in the literature, and the applicability of these models is compared and discussed.
Abstract: When the motion associated with an anatomical joint is to be measured, a kinematic model for the joint must first be established. The joint model will have from one to six degrees of freedom, and both the measurement technique and the means used to describe the motion will be influenced by the model and its degrees of freedom. This paper discusses the modeling and measurement of anatomical joint motion from a kinematics viewpoint. A review of the literature pertaining to measurement techniques, kinematic assumptions, and motion descriptions for anatomical joint motion is presented. One, two, three and six degree-of-freedom models for various anatomical joints have appeared in the literature, and the applicability of these models is compared and discussed.

Journal ArticleDOI
TL;DR: In this article, the authors considered the inverse kinematic problem of seismology in the compact domain M of dimension ν⩾,2 with the metric du, where the refraction indices n1, n2 are the solutions of the inverse Kinematic Problem, constructed relative to the functions τ1, τ2, respectively, and the differential form on δM×δM where τ=τ2−τ1,
Abstract: The following inverse kinematic problem of seismology is considered. In the compact domain M of dimension ν⩾,2 with the metric , we consider the problem of constructing a new metricdu=nds according to the known formula where ξ,ηeδM and Kξ,η is the geodesic in the metric du, connecting the points ξ, η. One proves uniqueness and one obtains a stability estimate , where the refraction indices n1, n2 are the solutions of the inverse kinematic problem, constructed relative to the functions τ1, τ2, respectively, is the differential form on δM×δM where τ=τ2−τ1, .

Proceedings ArticleDOI
TL;DR: In this article, a new pumping unit Kinematic Analysis method was developed for the calculation of position, velocity, acceleration of the polished rod, and torque factors as functions of crank angle.
Abstract: A new pumping unit Kinematic Analysis method was developed for the calculation of position, velocity, acceleration of the polished rod, and torque factors as functions of crank angle. This method can also be used to calculate the angular position, velocity and acceleration of any part of the pumping unit mechanism. It is more accurate than previous methods because it produces exact results. It can be used to compare pumping units, and can analyze units with varying crank speeds. It can improve gearbox torque analysis by including inertia effects, and can allow the use of conventional dynagraphs for the prediction of downhole dynagraphs.

Journal Article
TL;DR: A fully automatic optoelectronic photogrammetric technique is presented for measuring the spatial kinematics of human motion and estimating the inertial dynamics, finding that the noise and all other errors in the kinematic data contribute less than five percent error to the resulting dynamics.
Abstract: A fully automatic optoelectronic photogrammetric technique is presented for measuring the spatial kinematics of human motion (both position and orientation) and estimating the inertial (net) dynamics. Calibration and verification showed that in a two-meter cube viewing volume, the system achieves one millimeter of accuracy and resolution in translation and 20 milliradians in rotation. Since double differentiation of generalized position data to determine accelerations amplifies noise, the frequency domain characteristics of the system were investigated. It was found that the noise and all other errors in the kinematic data contribute less than five percent error to the resulting dynamics.

Proceedings ArticleDOI
Chi-Haur Wu1
22 Jun 1983
TL;DR: In this paper, a linear analytical model between the six Cartesian errors and the four independent kinds of kinematic errors has been developed and can be used as a guide to minimize the open-loop kinematics errors of the robot manipulator.
Abstract: The correct relationship between two connective joint coordinates of a robot manipulator is defined by four link parameters; one is the joint variable and the others are geomatrical values. Also, the basis for all open-loop manipulator control is the relationship between the Cartesian coordinates of the end effector and the joint coordinates. Hence, the fidelity of the Cartesian position and orientation of the end-effector to the real world depends on the accuracy of the four link parameters of each joint. In this paper, a linear analytical model between the six Cartesian errors and the four independent kinds of kinematic errors has been developed. Based on this model, the Cartesian error envelopes due to any combination of four kinds of kinematic errors can be uniquely determined. From the point of view of design, this error model can be used as a guide to minimize the open-loop kinematic errors of the robot manipulator. Finally, a new calibration technique based on this model has also been developed which can be used to correct the kinematic errors of the robot manipulator.