+ odom.twist.covariance[0] = 1e-3 # x
+ odom.twist.covariance[7] = 1e-3 # y
+ odom.twist.covariance[14] = 1e-3 # z
+ odom.twist.covariance[21] = 0.1 # rotation about X axis
+ odom.twist.covariance[28] = 0.1 # rotation about Y axis
+ odom.twist.covariance[35] = 0.1 # rotation about Z axis