Connect bodies with joint and constraint blocks to assemble them into an articulated system. The joint blocks determine the maximum degrees of freedom—rotational and translational—allowed between the connected bodies. The constraint blocks reduce this number by applying kinematic relationships that often couple degrees of freedom. There are no restrictions on model topology: you can model kinematic trees such as a double pendulum and kinematic loops such as a four bar.
|Prismatic Joint||Joint with one prismatic primitive|
|Revolute Joint||Joint with one revolute primitive|
|Spherical Joint||Joint with one spherical primitive|
|Weld Joint||Joint with zero primitives|
|Bearing Joint||Joint with one prismatic and three revolute primitives|
|Bushing Joint||Joint with three prismatic and three revolute primitives|
|Cartesian Joint||Joint with three prismatic primitives|
|Cylindrical Joint||Joint with one prismatic and one revolute primitives possessing parallel motion axes|
|Gimbal Joint||Joint with three revolute primitives|
|Pin Slot Joint||Joint with one prismatic and one revolute primitives possessing mutually orthogonal motion axes|
|Planar Joint||Joint with one revolute and two prismatic primitives|
|Rectangular Joint||Joint with two prismatic primitives|
|6-DOF Joint||Joint with one spherical and three prismatic primitives|
|Telescoping Joint||Joint with one prismatic and one spherical joint primitive|
|Universal Joint||Joint with two revolute primitives|
|Bevel Gear Constraint||Kinematic constraint between two bevel gear bodies with angled intersecting rotation axes|
|Common Gear Constraint||Kinematic constraint between two coplanar spur gear bodies with parallel rotation axes|
|Rack and Pinion Constraint||Kinematic constraint between a translating rack body and a rotating pinion body|
|Worm and Gear Constraint||Kinematic constraint between worm and gear bodies with perpendicular non-intersecting rotation axes|
Connecting bodies with joints, positioning and orienting joint frames through rigid transforms, and guiding joint assembly through by specifying joint state targets.
Workflow steps for assembling body subsystems into an articulated multibody model.
Role of joints in a multibody model. Joints as systems of joint primitives with elementary degrees of freedom. Accounting for the effects of joint inertia in a model.
Assemble body subsystems and revolute joints into an open-loop kinematic chain.
Assemble body subsystems and revolute joints into a closed-loop kinematic chain.
Use Mechanics Explorer and Model Report to identify and correct a model assembly error.
Learn how to satisfy the assembly requirements of gear constraints using Rigid Transform blocks.
Using the Simscape™ Statistics Viewer to determine the motion degrees of freedom in a mechanism.
Use a Point on Curve Constraint block to restrict the motion of an aircraft flap to a curved trajectory specified in a Spline block.
Use the Common Gear Constraint block to couple the rotational motions of the bodies comprising a planetary gear system.
Learn how to model gear constraints using simple gear models as examples.