Type synthesis of single-loop deployable mechanisms based on improved atlas method for single-DOF grasping manipulators

Abstract This paper presents a class of single degree-of-freedom (DOF) grasping manipulators (GMs) with multi-finger design composed of multiple single-loop mechanisms. A method is proposed to type synthesize single-DOF single-loop mechanisms (SLMs) using the improved atlas method. The conventional atlas method produces redundant mechanisms when the diversity of mechanisms is considered; the proposed method addresses this problem. SLM is split into two sub-chains. Sub-chain 1 has only one revolute pair, and one kinematic pair of sub-chain 2 is one revolute pair. Using these two revolute pairs, the type synthesis of SLMs is transformed into the type synthesis of the residual kinematic pairs of sub-chain 2. First, the constraint space of sub-chain 1 is analyzed using screw theory, and the constraint space of sub-chain 2 is further determined and classified. Subsequently, according to the classification of constraints, SLMs are further synthesized using the improved atlas method. Finally, this paper introduces the connection methods for typical SLMs and describes the construction of single-DOF GMs with multi-finger design.