# Simulation Commands

When coding robotics application with Robpod Studio, a set of special functions called **Simulation Commands** is available to better interact with the simulation environment from the robot program.

Simualtion Commands are particullary suited during [Off-Line Programming ](https://docs.robpod.cloud/simulation/off-line-programming)to let the robot grasp and move objects inside the simulation environment.

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All Simulation Commands starts with the **sim\_** prefix, i.e. **sim\_grasp()**.&#x20;

Here the complete list of simulation commands:

<table><thead><tr><th width="203">Command Name</th><th>Description</th><th>Parameters</th></tr></thead><tbody><tr><td><strong>sim_grasp</strong>(object)</td><td>Attach an object to robot tool. </td><td><strong>object</strong>: string - Name of object to attach to robot tool. If object is not specified, closest object to robot tool will be used.</td></tr><tr><td><strong>sim_release</strong>(object)</td><td>Detach an object from robot tool.</td><td><strong>object</strong>: string - Name of object to detach from robot tool. If object is not specified, all attached objects will be detached from robot tool.</td></tr><tr><td><strong>sim_set_parent</strong>(object, parent)</td><td>Attach an object to another parent while maintaining the current absolute position in the simulation.</td><td><strong>object</strong>: string - Name of the object to set the parent to. <strong>parent</strong>: string - Name of parent. If parent is not specified, object is attached to simulation workstation.</td></tr></tbody></table>

You can find here an example of pick and place application using Simulation Commands:

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UR Script file
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RoboDK workstation
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