Articulated hands force control and kinematic issues pdf

Warwick department of cybernetics, school of engineering and information sciences, university of reading, reading, berks rg6 2ay, u. Task planning robot hand grasp stability master processor external wrench. Hand designs with particular mobility properties are. The stanfordjpl hand is used as an example to illustrate a. Kenneth salisbury is currently a graduate student in the department of mechanical engineering at stanford university and is a student member of the ieee and the asme. To this end, the concept of kinematic dexterity is applied to such mechanical systems in this work. Merged citations this cited by count includes citations to the following articles in scholar. Craig department of computer science stanford university stanford, california 94305 j. Dynamic simulation of articulated soft robots nature. Megahed mechanical design and production department, faculty of engineering cairo unioersity, giza, egypt a bstract megahed, s.

However, it is difficult to control both the force and position of these hands at the same time. Table 1 parameters for dh for the manipulator articulated by two bars. However, the existence of joint flexibility makes those robots difficult to achieve high absolute position accuracy. Among these are the control of redundant degrees of freedom, grasp sta. Applications of the technology are being evaluated for tasks involving mechanical assembly and personal service. Modeling, control and path planning for an articulated vehicle.

Simultaneous gravity and gripping force compensation. The kinematic modelling and analysis of a 5axis stationary articulated robotic arm has been conducted by manjunath 3. The new metrics quantify the effective grasp region and grasp stability of underactuated hands. While their shortcomings can include friction and tendon compliance, in certain applications such as dexterous hands, they have distinct advantages over torquedriven systems including lightweight, low backlash, small size, high speed, and remote actuation. Pdf this paper presents the design of a new underactuated finger. The human controls the grasp force by sensing the friction force, that is, the. This thesis provides a framework for using articulated hands to perform local manipulation of objects. The kinematic dexterity is based on the condition number of the jacobian matrix of the mechanical system under study.

Investigated kinematic designs through dof counting chose hand dof based on geometric contact and force analysis 3 fingered hand, 3 joints per finger. The propensity of version i kinematic architecture to wholehand manipulation is. A cartesian impedance control for a 7dof space robotic arm sra based on the feedback from a 6dimensional force torque sensor on its end effecter is presented in this paper. Robotics and autonomous systems 7 1991 2735 27 northholland topological and kinematical study of tree structure robot manipulators. Underactuated robotic hands get a lot of attention in recent years. This paper deals with the conceptual and kinematic designs of a 5degree of freedom dof reconfigurable hybrid robot. The gripping force required for the robot hand to prevent the object from dropping is also simultaneously compensated for. Kinematic and isotropic properties of excavatormechanism ijert. Existance of hand designs with particular mobility properties is shown and a definition of accuracy points within manipulator workspace is given. The kinematic manipulability indices are derived extending previous results on cooperating robots without passive joints. The force control eliminates the indeterminate slack while commanding a parameterized space of. Hand designs with particular mobility properties are illustrated, and a definition of accuracy points within manipulator workspace is given. Several architectures for position and force control of this multiloop.

Tracking performance of a 3d articulated mobile manipulator. Articulated robots are the most common industrial robots for their large workspace and flexibility. Screw theory is used to show which finger configurations allow complete immobilization of the gripped object relative to the fingers, and also allow for the manipulation of the object by the fingers while maintaining the grasp. This paper presents a method to identify the joint stiffness of the robot. Design a hand capable of both rigid grasping and inhand manipulation approach. Pdf on the force capability of underactuated fingers. The robot is composed of a 2dof parallel spherical mechanism that is serially connected with a 3dof open loop kinematic chain via a prismatic joint. Salcudean and farrokh sassani, mechanism design for global isotropy with applications to haptic interfaces, the winter annual meeting of the asme, texas. The optimum kinematic design of spatial articulated hands can be formulated as an optimization problem. Schematic of an articulated manipulator with two bars. An approach to optimization of the physical dimensions of the jplstanford hand is given.

Kinematic and control issues are discussed in the context of an articulated, multifinger mechanical hand. The subject invention provides a modular, expandable and reconfigurable robotic system. This mechanism compensates for the gravitational torque produced by an object gripped by the handarm robot. Towards the analysis and optimization of underactuated hands. Among the drawbacks of presentday humanlike hands are the complex kinematic structure, the high number of actuators and the sophistication of sensing systems. Kinematic analysis and path planning of a new kinematically redundant planar parallel manipulator volume 26 issue 3 iman ebrahimi, juan a. Several different types of finger contacts are modeled and used in a number synthesis of threefingered hands.

Kinematic design of a 5dof hybrid robot with large workspace. Several architectures for position and force control. Automated design of special purpose dexterous manipulators. Roth, kinematic and force analysis of articulated mechanical hands, proceeding of asme design and production engineering technical conference, washington d. Given an underactuated tendondriven finger, the finger posture is underdetermined and can move freely flop in a region of slack tendons. In particular, it addresses the issues in effecting compliant motions of objects in cartesian space. Pdf torque control of underactuated tendondriven fingers. Modeling, control and path planning for an articulated vehicle thaker nayl issn. In this research work, a novel parallel manipulator with high positioning and orienting rate is introduced. In this paper, we propose a novel mechanism to compensate for gravity and the gripping force in a handarm robot.

The reaction force r should be in the frictional cone zone k. Kinematic analysis of a novel complex dof parallel manipulator. Often people attempt to live their lives backwards. Principles on the development of mechanical hands which can manipulate objects by means of active control. Application of dexterity indices to spatial articulated hands. Force control and kinematic issues salisbury 1982 2 a multiobjective optimum design of general 3r manipulators for prescribed workspace limits ceccarelli 2004 3 contribution to the optimization of closedloop multibody systems. Topological and kinematical study of tree structure robot. Indeed, the preferred approach to transmit the motion to the joints from the actuators consists of using a mechanical transmission system that is generally composed of a combination of bodies, tendons, gears, springs and pulleys. In this paper, we propose a grasping force control method based on position control for manipulation. This mechanism has two rotational and one translational degree of free. This report presents issues relating to the kinematics and control of dexterous robotic hands using the utahmit hand as an illustrative example.

Pdf a forceisotropic underactuated finger researchgate. This work shows that such an underactuated finger can be operated in tendon force control rather than position control with effective performance. In one aspect of the invention there is provided a robot having at least two manipulators each having several compact rotary joints. Tendondriven hands have been designed for the purposes of grasping and manipulation. Now we can use this table to perform the transformation matrices. Force control and kinematic issues, the international journal of robotics research, 1982. Exercises 161 if the velocity vector at the origin of a is 0.

A mathematical introduction to robotic manipulation. Cartesian impedance control for space robotic arm based on. Shown in this paper is how to determine the forces applied by the fingers on the. Us5523662a modular, expandable and reconfigurable robot. Determination of grasp forces for robot hands based on human. A novel synthesis of computational approaches enables. Thus we can construct the table with the dh parameters. Joint stiffness identification and flexibility compensation. The prototype of the new handarm manipulator, currently at the setup phase, is described in detail, focusing on the developed solutions with respect to sensorial equipment, handarm mechanical integration, and control algorithms for coordination of the arm and hand subsystems to obtain both structural and functional integration. Optimization of tlte physical dimensions of the stanfordjpl hand is described. In order to analyze the grasp ability and optimize structure parameters of underactuated hands for effective grasp, new grasp performance metrics have been defined. Salisbury, jk and craig, jj 1982 articulated hands force control.

The ones marked may be different from the article in the profile. Their combined citations are counted only for the first. Several architectures for position and force control of this. Forcesensing actuator with a compliant flexuretype joint.