The robotic arm's motor generates a rotational speed of 1000 RPM (revolutions per minute) at the input shaft. The first gear in the compound system has 18 teeth and meshes with a second gear with 36 teeth. The second gear is mounted on the same shaft as the third gear with 72 teeth. The third gear engages a fourth gear with 48 teeth, which is connected to the main shaft of the robotic arm. Given the following additional information: The moment of inertia of the robotic arm's load is 0.2 kgm. The efficiency of each gear pair is 90%. The torque generated by the motor at the input shaft is 15 Nm