### Instrument visual model

Description:

In this scene, we build the basics for a moving object.

Key points:

- First, we put a gravity in the whole scene with the Gravity component.
- We set the instrument as a MechanicalObject. It describes the state of the particles of the object.
- To compute the states at each time step, we need a time integrator, like the EulerImplicitSolver.
- We need a linear solver, like CGLinearSolver, to solve the linear system generated with our implicit solver.
- We finally add a mass to the object with the UniformMass component.

Note:

The gravity can be set in a node with the vec3d argument gravity instead of with a component.

See other tutorials to learn more about time integration.

### Next