This paper presents an approach to the profile synthesis of planar, variable joints by combining higher variable joints. The possible permutations of planar, variable joints that change from a rotational to translational motion will be enumerated. A method will be provided to determine the profiles of variable joints, and a practical example will be presented to illustrate the proposed method.

This paper introduces mechanism state matrices as a novel way to represent the topological characteristics of planar reconfigurable mechanisms. As part of this new approach, these matrices will be used as an analysis tool to automatically determine the degrees of freedom (DOFs) of planar mechanisms that only contain one DOF joint. The DOF at each state can be combined with a mechanism state matrix to form an augmented mechanism state matrix. A series of examples will be used to illustrate the proposed concept.

Abstract. In light of technological advances, researchers have lost sight of robotic grippers/end effectors design intent. In a semi-structured environment the biomimetic approach is impractical due to the high complexity of the mechanism and control algorithms. Current industrial grippers are robust, but lack the flexibility that allows for in hand manipulation. The authors believe that underactuated grippers provide the best approach to allow for in hand manipulation along with being rugged enough for an industrial setting. Thinking of the robotic gripper and the robotic arm as one system (as opposed to two separate subsystems), one is capable of using the degrees of freedom of the robot in conjunction with that of the gripper to provide the desired motion profile without the complexity of running two subsystems. This paper will outline where recent grippers have failed and will introduce a new design paradigm for grippers along with several underactuated gripper ideas.

This paper improves augmented mechanism state matrices by replacing joint code with screw system notation. The proposed substitution allows for a more specific description of the joints in the mechanism and the capability to describe both spatial and planar mechanisms. Examples are provided which elucidate the proposed approach.

This paper provides an algorithm allowing a designer to perform three position rigid body guidance with specified moving pivots for a 4R-RRRP mechanism with variable topology (MVT). A mechanism with variable topology is a mechanism that changes from one topological state to another due to a change in joint geometry. Both a graphical approach and an algebraic solution are presented. An example is provided in which a circuit defect in a 4R mechanism can be avoided using a 4R-RRRP mechanism. Two additional examples are provided that show the results of this new theory. Practical applications for this theory are found in many industries including manufacturing, aerospace, and healthcare.