# Accelerometers

Accelerometer entities measure acceleration in the simulation.

In the LS-DYNA interface, Accelerometer entities are defined by three nodes. The first node defines the base point, and the other two nodes define a local coordinate system in which accelerations are measured. There are additional fields that enable you to adding a mass or subtract the acceleration due to gravity from the computed acceleration output.

In the Radioss interface, Accelerometer entities are defined by a node and a local coordinate system of type SKEW. This coordinate system is not mandatory. If it is not defined, accelerations are measured in the global coordinate system, otherwise, in the defined local coordinate system

## LS-DYNA Cards

Card Description
*ELEMENT_SEATBELT_ACCELEROMETER Defines a seat belt accelerometer.