The Study On Inverse Substructure Analysis Method Of Product Transport Packaging System

Since the shock and vibration characteristics of product is vital for the packaging designof the product, this paper proposes a new transport packaging system dynamic analysis theoryand buffer performance evaluation method to deal with the current problems and challengesof product protection in logistics. With a review of the research status of the single degree offreedom, many degrees of freedom and random excited dynamics of package cushioning, theshock and vibration characteristics of product within the road excitation, inverse substructuretheory and buffer performance evaluation method, this paper firstly gives an introduction toits research significance.In logistics, the product and the vehicle can usually constitute a two-substructure coupledsystem through packaging. The critical component-product-vehicle system is treated as athree-substructure multi-coordinate coupled system. It is composed of a critical component, aproduct and a vehicle, which are connected by a fixed installation structure and a packagingone. The two-substructure coupled inverse substructure theory, extended fromtwo-substructure coupled substructure theory, can be used to analyze the dynamiccharacteristics of product-vehicle system. The three-substructure coupled substructure theoryis extended from two-substructure coupled substructure theory, with two-substructure coupledinverse substructure theory, the three-substructure coupled inverse substructure theory isfurther proposed. Based on that, the dynamic characteristics of criticalcomponent-product-vehicle system can be thoroughly analyzed. The lumped parameter modeland the physical prototype model for the product-vehicle and criticalcomponent-product-vehicle three-substructure multi-coordinate coupled systems areconducted to respectively verify the validity and accuracy of the two-substructure and thethree-substructure multi-coordinate coupled inverse substructure theorys.This paper conducts a research on the vibration transmission ability and the cushioningeffect of the coupling points of the packaging units. Based on frequency response function,two-substructure and the three-substructure multi-coordinate coupled inverse substructuretheory, the concepts of the vibration contribution, vibration contribution ratio, overallvibration contribution and overall vibration contribution ratio to product response or criticalcomponent response through each packaging unit are introduced.By adopting the simple and practicable experimental method which uses impact hammerexcitation to recognize the vibration characteristics. this paper proposes a dynamic testmethod for the vibration characteristics recognization of the product-vehicle system and thecritical component-product-vehicle system. Based on that, it conducts online tests of the refrigerator-truck and the compressor-refrigerator-truck multi-coordinate coupled system.The results of the online tests verify the validity and accuracy of the method. Seen from thewhole frequency range, the vibration contributions of the compressor and refrigerator atdifferent coupling points are almost matched. But for most frequencies, the total vibrationcontribution ratios of the compressor and refrigerator at different coupling points are different.The values of overall vibration contribution and overall vibration contribution ratio reveal thatthe vibration transmission ability and buffering effects of different coupling points ofcoupling units in a package are different.