In this paper, velocity harmonization and acceleration harmonization of a 2R-1P3R two-arm robot have been studied for special-shaped surface stone with the differential geometry theory and D-H method.

A heavy stone may have been used to hit the sharp stone into the surface.

But one day he heard a strange noise at his feet, and when he looked down to see what it could be, he saw a stone-cutter driving tools into his surface.