  Employing an inertial measurement unit (IMU) as an additional sensor can
dramatically improve both reliability and accuracy of visual/Lidar odometry
(VO/LO). Different IMU integration models are introduced using different
assumptions on the linear acceleration from the IMU. In this paper, a novel IMU
integration model is proposed by using switched linear systems. The proposed
approach assumes that both the linear acceleration and the angular velocity in
the body frame are constant between two consecutive IMU measurements. This is
more realistic in real world situation compared to existing approaches which
assume that linear acceleration is constant in the world frame while angular
velocity is constant in the body frame between two successive IMU measurements.
Experimental results show that the proposed approach outperforms the
state-of-the-art IMU integration model. The proposed model is thus important
for localization of high speed autonomous vehicles in GPS denied environments.
