File: geometry_msgs/TwistWithCovariance.msg
# This expresses velocity in free space with uncertianty.
Twist twist
# Row-major representation of the 6x6 covariance matrix
# The orientation parameters use a fixed-axis representation.
# In order, the parameters are:
# (x, y, z, rotation about X axis, rotation about Y axis, rotation about Z axis)
float64[36] covariance
Expanded Definition