Add forces, torques, and motion inputs to drive your model and use sensors to measure its dynamic response. Use the joint blocks in your model to actuate those joints, model their internal mechanics, and sense joint-specific dynamic variables. Only Joints blocks allow you to specify trajectories in a model.
Use Forces and Torques blocks to model interactions between unconnected bodies or to add special dynamic elements such as gravitational fields and nonlinear spring-dampers—the latter using the generic Internal Force block. You can sense the relative motions of unconnected bodies using the Transform Sensor block.
|External Force and Torque||General force and torque arising outside the modeled system|
|Gravitational Field||Field of force due to point mass|
|Internal Force||General force acting reciprocally between two frame origins|
|Inverse Square Law Force||Force proportional to the inverse square distance between two frame origins|
|Spatial Contact Force||Apply contact forces between a pair of connected bodies|
|Spring and Damper Force||Force proportional to the distance and relative velocity between two frame origins|
Simulate a four-bar model at different coupler link lengths and plot the resulting coupler curves.
Dynamic variables that you can sense and blocks that you can use to sense them.
Use the Transform Sensor block to sense frame motion in a simple multibody model.
Use the sensing capability of a joint block to sense the internal forces acting on a mechanical link.
Use the sensing capability of joint blocks to measure the forces and torques acting at a joint.
Use the Spatial Contact Force block to model normal and frictional forces between solid blocks.
Use the Spatial Contact Force block to model the wheels of a car rolling down a ramp.
Assemble a system of gravitationally-bound free bodies using Cartesian Joint and Gravitational Field blocks.
Use the actuation capability of joint blocks to specify the trajectory of frame.
Use the actuation capability of a joint block to specify the actuation torque on a joint.
Use the actuation capability of joint blocks to specify the trajectory of a frame.
Use contact proxies to increase the speed and robustness of contact simulations.
Using physical signals to specify actuation inputs and obtain sensing outputs.
Restrictions and special considerations for models with motion actuation inputs in joint blocks.
Workflow steps for setting and sensing dynamic quantities such as force, torque, position, and more.
Modeling the effects of uniform gravity, gravitational fields, and individual gravitational forces. Software definition of body boundaries and its impact on gravitational torques.
Joint actuation modes, motion input handling, and key differences between model assembly and simulation.
Forces and torques that you can sense and the blocks that you can use to sense them.
Measurement frame definition and summary of measurement frame types.
Motion variables that you can sense and the blocks that you can use to sense them.
Rotational motion variables that you can sense and the blocks that you can use to sense them.
Translational variables that you can sense and the blocks that you can use to sense them.