Which of the following represents the robot's major axes?

The major axes of a robot typically refer to the primary joints that allow for the most significant movements and positioning capabilities in robotic arms. In the case of FANUC robots, the designations J1, J2, and J3 correspond to the primary rotational joints that provide the robot with a large range of mobility and flexibility.

J1 is generally the base joint, allowing the robot to rotate around a vertical axis, which is crucial for positioning the entire arm. J2 represents the shoulder joint, which provides significant lift and extension capabilities. J3 is the elbow joint, enabling the arm to flex and extend, allowing for more intricate movements and reach.

By choosing J1, J2, and J3, you are identifying the foundational axes that contribute most to the robot’s ability to manipulate objects and navigate its work envelope effectively. This understanding of how these major axes relate to the robot's articulation and movements is critical for effective programming and operation in handling tasks.

The other combinations are less representative of the major axes as they include joints further along the chain that typically offer finer control or additional motions but are not part of the primary frame of reference for fundamental movement.