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.
|Abstract base class for components|
|Abstract base class for joints|
|Specify structure of multibody system|
|Construct rigid body|
|Construct rigid transform|
|Construct rigid solid|
|Construct world frame|
|Construct constant-velocity joint primitive|
|Abstract base class to construct joint primitives|
|Construct lead-screw primitive|
|Construct prismatic joint primitive|
|Construct revolute joint primitive|
|Construct spherical joint primitive|
|Construct rotation by using aligned-axes parameterization|
|Construct rotation by specifying custom axis-angle pair|
|Construct Cartesian translation|
|Construct cylindrical-axis translation|
|Construct rotation by using unit quaternion|
|Abstract base class for 3-D rotations|
|Construct rotation by using rotation matrix|
|Construct rotation by using rotation-sequence parameterization|
|Abstract base class for 3-D translations|
|Construct rotation by using standard-axis parameterization|
|Construct standard-axis translation|
|Construct zero rotation|
|Construct zero translation|
Joints with One or No Primitives
|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|
Joints with Multiple 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|
Joints with Coupled Degrees of Freedom
|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|
Assembling Bodies with Joints
- Creating a Multibody with different joints in MATLAB
This example shows how to build a multibody containing various joints in MATLAB.
- How Multibody Assembly Works
Connecting bodies with joints, positioning and orienting joint frames through rigid transforms, and guiding joint assembly through by specifying joint state targets.
- Multibody Assembly Workflow
Workflow steps for assembling body subsystems into an articulated multibody model.
- Modeling Joint Connections
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.
- Model an Open-Loop Kinematic Chain
Assemble body subsystems and revolute joints into an open-loop kinematic chain.
- Model a Closed-Loop Kinematic Chain
Assemble body subsystems and revolute joints into a closed-loop kinematic chain.
- Troubleshoot an Assembly Error
Use Mechanics Explorer and Model Report to identify and correct a model assembly error.
Constraining Multibody Assemblies
- Assemble a Gear Model
Learn how to satisfy the assembly requirements of gear constraints using Rigid Transform blocks.
- Counting Degrees of Freedom
Using the Simscape™ Statistics Viewer to determine the motion degrees of freedom in a mechanism.
- Constrain a Point to a Curve
Use a Point on Curve Constraint block to restrict the motion of an aircraft flap to a curved trajectory specified in a Spline block.
- Model a Compound Gear Train
Use the Common Gear Constraint block to couple the rotational motions of the bodies comprising a planetary gear system.
- Modeling Gear Constraints
Learn how to model gear constraints using simple gear models as examples.