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This report updates the various designs and prototypes tested since the last Conference. Included are the operational data of a subassembly of the old 200 × 200 GeV machine design as well as the latest larger prototype ring magnets with their strong points and shortcomings. The working line coil system design presently seems to be nearly completed, having gone through major revisions to increase its possible operational range. One of the major design goals of the magnet series, that of each unit being able to absorb their own energy, seems to be well in hand. This feature enables the magnet string to be protected without external intervention, i.e., without external energy dump or driving the magnet winding normal by an active external circuit. Simply stated, this means that the magnet's L/R time constants during quench are short enough to prevent thermal damage. There are two series of prototypes. The first type is the so called "Standard" which will become the ring magnet for ISABELLE. The second is that in which various characteristics and/or limits of various parameters are explored. Various parameters such as specific heat of the windings, increased metal packing fractions, and resistivity of turns (in the normal state) are bracketed. The 400 × 400 GeV version of ISABELLE1 requires acold aperture of 13.09 cm, quadrupole magnetic length of 1.6 m, and dipole length of 4.65 m at a peak dipole field of 5.0 T. Two machine size dipoles and one quadrupole are being presently tested.

This paper focuses on the direct workspace problems of a general geometry fully-parallel-actuated, planar three-degree-of-freedom platform-type manipulator. A set of equations are presented that determine the workspace as a function of the platform orientation. The formulation is governed by the solution to the inverse position problem of the manipulator. The reachable positions of the end-effector point, for a specified platform orientation, are analyzed. To illustrate the concepts, a practical example is included where the end-effector is required to move a cup filled with water. Then the platform orientation, for a specified location of the end-effector point, is studied. If an arbitrary orientation is possible, the specified location of the end-effector point is said to be within the primary workspace. The paper includes a detailed discussion of the total primary workspaces of the manipulator. The approach adopted here is to regard the manipulator as a combination of three planar, three-revolute open chains. For the sake of completeness, the influence of special manipulator geometry on the workspace is also discussed. Finally, the paper includes the conditions that cause stationary configurations of the manipulator. Insight into these undesirable configurations is provided by a study of the location of the absolute instant center of the platform.

The paper presents solutions to the forward position and velocity problems of a planar eight-bar, three degree-of-freedom, closed-loop linkage. The linkage is proposed as a programmable platform-type robot which can both position and orient the platform. A sixth-order polynomial equation in the angular displacement of the platform is derived which indicates that six configurations, for a given set of input angular displacements, are possible. The polynomial equation is important in the study of the limit positions of the linkage. The forward velocity problem is solved using first-order partial derivatives of the four output angular displacements with respect to the three independent input displacements. The partial derivatives provide geometric insight into the kinematic analysis of the linkage. A graphical method, which utilizes the instantaneous centers of zero velocity, is introduced as a check of the velocity analysis. The method is solely a function of the configuration of the linkage and is, therefore, a practical alternative to other methods which rely on velocity information. For illustrative purposes, the paper includes a numerical example of the linkage used as a planar platform-type robot.

The paper presents solutions to the forward position and velocity problems of a planar eight-bar, three degree-of-freedom, closed-loop linkage. The linkage is proposed as a programmable platform-type robot which can both position and orient the platform. A sixth-order polynomial equation in the angular displacement of the platform is derived which indicates that six configurations, for a given set of input angular displacements, are possible. The polynomial equation is important in the study of the limit positions of the linkage. The forward velocity problem is solved using first-order partial derivatives of the four output angular displacements with respect to the three independent input displacements. The partial derivatives provide geometric insight into the kinematic analysis of the linkage. A graphical method, which utilizes the instantaneous centers of zero velocity, is introduced as a check of the velocity analysis. The method is solely a function of the configuration of the linkage and is, therefore, a practical alternative to other methods which rely on velocity information. For illustrative purposes, the paper includes a numerical example of the linkage used as a planar platform-type robot.

This paper focuses on the direct workspace problems of a general geometry fully-parallel-actuated, planar three-degree-of-freedom platform-type manipulator. A set of equations are presented that determine the workspace as a function of the platform orientation. The formulation is governed by the solution to the inverse position problem of the manipulator. The reachable positions of the end-effector point, for a specified platform orientation, are analyzed. To illustrate the concepts, a practical example is included where the end-effector is required to move a cup filled with water. Then the platform orientation, for a specified location of the end-effector point, is studied. If an arbitrary orientation is possible, the specified location of the end-effector point is said to be within the primary workspace. The paper includes a detailed discussion of the total primary workspaces of the manipulator. The approach adopted here is to regard the manipulator as a combination of three planar, three-revolute open chains. For the sake of completeness, the influence of special manipulator geometry on the workspace is also discussed. Finally, the paper includes the conditions that cause stationary configurations of the manipulator. Insight into these undesirable configurations is provided by a study of the location of the absolute instant center of the platform.

The ISABELLE superconducting magnet is supported at the quarter points within a carbon steel vacuum vessel by four fiberglass straps. These are positioned at a small angle to the vertical so that contraction of both the magnet core and the suspension straps do not change the position of the magnet centerline. Two smaller fiberglass straps at each support provide horizontal position location. The fiberglass straps are fabricated of uniaxial epoxy fiberglass tape. Creep tests at room temperature and 1.3 times design load show no extension after one year and there was a factor of safety of 5 in breaking strength. An Engineering Test Model was constructed and cycled to 5° K. Heat leak for the eight straps was less than 0.5 W and position stability was within ± 0.005¿. The vacuum vessel is vertically positioned by means of three jack screws with sliding pads and spherical washers between the top of the jacks and the support boxes. Longitudinal and lateral positioning is done by three horizontal screws at each support box. Three shim plates on the top of the support boxes are used to set the magnetic plane and sockets in two of these are used to set the lateral plane.