Joint Space Mass Matrix

R2026b

Joint-space mass matrix for robot configuration

• 

Joint Space Mass Matrix block

To add a block to a model, double-click the canvas and start typing the block name. Then, select the block from the list.

Libraries:
Robotics System Toolbox / Manipulator Algorithms

Description

The Joint Space Mass Matrix block returns the joint-space mass matrix for the given robot configuration (joint positions) for the Rigid body tree robot model.

Examples

Get Mass Matrix for Manipulators in Simulink

Calculate the mass matrix for robot manipulators using a rigid body tree robot model passed to manipulator algorithm blocks in Simulink^®.

• Open Script

Ports

Input

Config — Robot configuration

vector

Robot configuration, specified as a vector of positions for all nonfixed joints in the robot model, as set by the Rigid body tree parameter. You can also generate this vector for a complex robot using the homeConfiguration or randomConfiguration functions inside a Constant or MATLAB Function block.

Output

MassMatrix — Joint-space mass matrix for configuration

positive-definite symmetric matrix

Joint-space mass matrix for the given robot configuration, returned as a positive-definite symmetric matrix.

Parameters

Rigid body tree — Robot model

twoJointRigidBodyTree (default) | RigidBodyTree object

Robot model, specified as a rigidBodyTree object. You can also import a robot model from an URDF (Unified Robot Description Formation) file using importrobot.

The default robot model, twoJointRigidBodyTree, is a robot with revolute joints and two degrees of freedom.

Simulate using — Type of simulation to run

Interpreted execution (default) | Code generation

• Interpreted execution — Simulate model using the MATLAB^® interpreter. This option shortens startup time but has a slower simulation speed than Code generation. In this mode, you can debug the source code of the block.

• Code generation — Simulate model using generated C code. The first time you run a simulation, Simulink generates C code for the block. The C code is reused for subsequent simulations, as long as the model does not change. This option requires additional startup time, but the speed of the subsequent simulations is comparable to Interpreted execution.

Tunable: No

Programmatic Use: Add Block

To add the block programmatically, use the add_block function with one of these library block paths as the source.

"robotmaniplib/Joint Space Mass Matrix"

Example: add_block("robotmaniplib/Joint Space Mass Matrix","myModel/myBlock",MakeNameUnique="on")

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2018a