In picture one I have shown a robot arm (green) rotating to pick up a box, using a fulcrum (red). The arm after rotating is shown with black rectangle. The vertical arm on the left is attached to the horizontal green arm and goes down to make the green arm rotate.
In picture two, I have shown a robot arm which goes up and down to pick up the box, connected to a Revolute shoulder on the left which is not shown in the picture.
I have tried to modify the second picture, so I have created the first picture. I wanted to use fulcrum and related physics theorems to make the picking up easier for the robot.
Can you please tell me if I am making mistake and this is not a way to modify the arm and to make picking up easier? Does the red object act as a fulcrum?