【摘要】 分析了求解平面机构瞬心的各种途径， 阐述了三心定理的应用方法和应用上的局限性，探讨了罗洪田定式［１］在平面机构瞬心求解中的组合应用更多还原

【Abstract】 Detailed means of solution of the instantaneous center of planar mechanism are given and the application method as well as its limit of the three link theorem is discovered.The assemble application of Lou Hongtian’s theorem in solution of instantaneous center of planar mechanism is also discussed.更多还原