An attitude estimation system for amphibious spherical robots

Abstract

As one of the most effective tools for exploring the ocean, automatic underwater vehicles have attracted a lot of attentions for years. But some key problems have not been solved properly. It is especially difficult to design underwater vehicles in small size. In this paper, three inertial sensors were adopted to fabricate an attitude estimation system, which provided posture information for our amphibious spherical robot to realize motion control and autonomous navigation. The pitch, roll and heading angel were acquired from current robot attitude matrix, which was calculated from the quaternion algorithm. And the attitude was corrected by the fusion of accelerometer and magnetic sensor. Experimental results verified the validation and precision of the robotic attitude estimation system. It has manifested that the system is effective to realize the robot control and navigation.

A Customized Extended Kalman Filter for Removing the Impact of the Magnetometer’s Measurements on Inclination Determination

“…MIMUs are widely used in several applications where the determination of the inclination (including the pitch and roll) and azimuth (also called yaw or heading) of rigid bodies is required. Among the above-mentioned applications, the most conventional is the movement analysis of human body segments [ 1 , 2 ], followed by the inclination and azimuth sensing of small and medium-sized machines (usually autonomous equipment) flying through the air but near the ground [ 3 ], sailing under water [ 4 , 5 ], and driving on the ground [ 6 ]. Despite the fact that other methods, such as vision-based methods and GNSS-based methods, can also be applied for determining the inclination and azimuth, MIMUs have their unique superiorities, including their low cost, small size, light weight, and non-reliance on external artificial sources.…”