Answer: A, B, D.
Answer: The movement of the robot arm includes vertical movement, parabolic motion, and rotary motion, but not radial movement.
The design and locomotion of a robotic arm depends on the characteristics of its structure and control system. In general, the robot arm has the following modes of movement:
Vertical movement: The robot arm can move up and down in the vertical direction to adapt to workpieces or work areas of different heights.
Parabolic motion: The robot arm can move along a parabolic trajectory to achieve more complex spatial movements.
Rotary motion: The robot arm can rotate around the central axis to change the direction or attitude of the movement.
In general, the robot arm does not move radially because this type of movement has no practical meaning for the robot arm. Radial movement is often used to describe the overall motion of a robot or how it moves in a work scene.
So, depending on the title, the answer is ABD.