This paper experimentally studies how the mechanism and system design of a manipulator affect the impact force when the manipulator collides with its environment. Although considerable safety-related research has been conducted, there has been no research comparing tendon-driven and direct-driven mechanisms. In this paper, from the perspective of impact force and impulse, two types of driving mechanisms are experimentally compared; a tendon-driven mechanism and a direct-driven mechanism. Also the effect of the absorber and the collision detection system are experimentally investigated. Finally, based on the knowledge obtained above, a single system design method of the manipulator to reduce the collision impact force is proposed and experimentally evaluated.