Dead-reckoning inverse and direct kinematic solution of a 4W independent driven rover

We tackle the problem of trajectory control of a four-wheel driven skid-steering (4WDSS) robotic platform with asynchronous wheels velocity. A practical mathematical formulation for solving inverse and direct kinematics is provided. This approach also includes the formulation and implementation of a home made arrange of accelerometers to infer robot displacements in global coordinates system. Although we provide a direct kinematics solution, we further establish an inverse kinematics formulation using four parameters to exert trajectory control, namely instantaneous linear velocity, angular velocity, and robot Z-turning axes. The formulation for robot angular velocity is given differently from other research approaches, where it is stated in terms of the robot´s geometry, which directly impacts the robot´s swift capability. Trajectory control is yielded by controlling the location of the robot turning Z-axis with respect to the instantaneous center of rotation by direct control of the wheels speeds.