Computational solution of the direct kinematics problem of a biped robot leg

The work presented in this paper, addresses the way the direct kinematics problem of a biped robot leg is solved by computational means. This problem is present in many robot structures due the actuators are not aligned with the axis of rotation of every structure joint. As a consequence the relations between the joint position and the position shaft of the actuator are not linear. In the presence of this scenario, the solution for the calculation of the respective joint position in function of the motor shaft position, is not analytical and the numerical methods are indispensable. The principle of solution is based on the same non linear position relations between the joint and the actuator. The on line searching technique named "Tracking the last calculated value" of the corresponding value of the joint position, is carried out without the usage of look-up tables or numerical methods.