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Mechanism Configuration

Mechanism-wide gravity and simulation parameters

  • Mechanism Configuration block

Libraries:
Simscape / Multibody / Utilities

Description

The Mechanism Configuration block specifies the gravity and simulation parameters of the mechanism to which the block connects. The simulation parameters include the perturbation value for computing numerical partial derivatives during linearization and the iteration number for the joint mode transition.

A Simscape™ Multibody™ network can have at most one instance of the Mechanism Configuration block. If a model does not have the Mechanism Configuration block, the uniform gravity applied to the mechanism is zero.

If a Simscape Multibody network contains a Gravitational Field block, set the Uniform Gravity parameter of the Mechanism Configuration block to None.

Ports

Frame

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Port to use to connect the mechanism. The settings of the Mechanism Configuration block apply only to the mechanism to which the block connects.

Input

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Uniform gravity of the mechanism to which the Mechanism Configuration block connects.

Dependencies

To enable this port, set Uniform Gravity to Time-Varying.

Parameters

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Uniform Gravity

Method used to calculate the uniform gravity for the mechanism to which the Mechanism Configuration block connects, specified as one of these options:

MethodDescription
ConstantUse the Gravity parameter to specify the gravitational acceleration vector that remains constant in space and in time.
Time-VaryingUse the physical port g to specify the gravitational acceleration vector that remains constant in space but varies in time.
NoneSpecify zero uniform gravity for the mechanism. This option must be used if the Simscape Multibody network contains a Gravitational Field block.

Constant gravitational acceleration vector, specified as a 1-by-3 vector, [gx gy gz]. The block resolves the vector in the world frame of the mechanical system.

Dependencies

To enable this parameter, specify Uniform Gravity to Constant.

Perturbation value for computing numerical partial derivatives during linearization, specified as a positive scalar. For more information about linearization, see Linearize Nonlinear Models (Simulink Control Design) and linmod.

Joint Mode Transition

Number of Newton iterations to use for solving the positions of all the joints in the mechanism when the mechanism has one or more joints that transition from disengaged to normal mode, specified as a positive integer.

When a joint transitions from disengaged to normal mode, if that joint has large discrepancies in its location and orientation, the Simscape Multibody network may need a larger number of iterations to compute the required positions of all joints in the mechanism that satisfy the kinematic constraints of that transitioning joint.

Extended Capabilities

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

Version History

Introduced in R2012a