# QDOT

The QDOT() function returns the modal velocity for the requested mode (m_id) for the flexible body specified (f_id). This function can be used in your model as a valid MotionSolve expression.

QDOT(f_id, m_id)

## Arguments

f_id
The ID of the flexible body in the model.
m_id
The mode ID whose velocity is requested.
Note: m_id > 6, that is, the expression is only supported for non-rigid body modes.

## Example

<Post_Request
id               = "2"
type             = "EXPRESSION"
label            = "Modal displacement"
expr2            = "QDOT(30102,7)"
expr3            = "QDOT(30102,8)"
expr4            = "QDOT(30102,9)"
expr6            = "QDOT(30102,10)"
expr7            = "QDOT(30102,11)"
expr8            = "QDOT(30102,12)"
/>