Structural Synthesis of Ancient Chinese Chu State Repeating Crossbow

Abstract

Chu State repeating crossbow is a reconfigurable mechanism which was found in the tomb and dated back to the fourth century BC in ancient China. Since crossbows have diversified types and were widely used in ancient China after the Spring and Autumn Period (770-476 BC), Chu State repeating crossbow should have many designs in different eras and regions. The aim of this work is to synthesize mechanism structures of Chu State repeating crossbow. Based on the analyses of crossbows, the structural characteristics and design constraints of this device are concluded. Then, according to the concepts of generalization and specialization subject to the concluded design constraints, seven feasible structures of mechanism that meet the technological standards of the subject’s time period are reconstructed.