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Disassembled Revolute - Represent disassembled revolute joint with one rotational degree of freedom about misaligned axes

Library

Joints/Disassembled Joints

Description

The Disassembled Revolute block represents a single rotational degrees of freedom (DoF) along a pair of specified misaligned axes between two bodies. SimMechanics simulation automatically assembles (aligns) the rotation axes at simulation start when it defines a machine's assembled configuration.

Disassembled Revolute Axes of Follower (blue) and Base (red)

Satisfying Joint Requirements

A Joint block represents the relative degrees of freedom between two bodies, not the bodies themselves.

You must connect any Joint block to two and only two Body blocks, the base and the follower. All Joints have a default of two connector ports for these connections, defining the direction of joint motion (base to follower). You connect each side of the Joint block to these Body blocks at a Body coordinate system (CS) point.

You specify the joint primitive axes, if any, in the Joint dialog. The two disassembled primitive joint axes are associated, in order, with the base and follower Bodies, respectively.

You cannot connect an Actuator or Sensor to a Disassembled Joint.

Assembly Restrictions on Disassembled Joints

This Joint block is disassembled: the connected Body CS origins do not need to be spatially collocated points or lie within the span of prismatic primitives, if any.

You can only use a Disassembled Joint block within a closed loop. One loop can have no more than one disassembled joint.

Dialog Box and Parameters

The dialog has two active areas, Connection parameters and Parameters.

Connection Parameters

Current base: When you connect the base (B) connector port on the Disassembled Revolute block to a Body CS Port on a Body, this parameter is automatically reset to the name of this Body CS. See the following figure, Disassembled Revolute Base and Follower Body Connector Ports.
Current follower: When you connect the follower (F) connector port on the Disassembled Revolute block to a Body CS Port on a Body, this parameter is automatically reset to the name of this Body CS. See the following figure, Disassembled Revolute Base and Follower Body Connector Ports.

Disassembled Revolute Base and Follower Body Connector Ports

Parameters

There is one Axes tab.

The entries on the Axes tab are required. They specify the directions of the two misaligned axes of the rotational DoF that the Disassembled Revolute represents.

Name: This column automatically displays the names of the two misaligned rotation axes attached to base and follower bodies, respectively.
Axis of rotation [x y z]: Enter here as two three-component vectors the two misaligned directional axes about which the base and follower bodies respectively can rotate. The default vectors are [1 0 0] and [0 1 0], respectively. The axes are directed vectors whose overall signs matter.
Reference CS: Using the pull-down menu, choose the coordinate systems (World, the base Body CS, or the follower Body CS) whose coordinate axes the two vector axes of rotation are oriented with respect to. The defaults are World.

Restricted Parameters