A mechanical arm includes a first link connectable to a surface, a second link, a third link, a fourth link, and a fifth link that are coupled to one another in series, and an end effector connectable to the fifth link. The end effector is rotatable about an axis of rotation same as an axis of rotation of the fourth link, and rotatable about an axis of rotation orthogonal to the axis of rotation of the fourth link. The first link, the second link, the third link, the fourth link, and the fifth link are collectively structured and configured to rotate such that the end effector is actuatable to a workspace under the surface.