Effect of Impact Loading Conditions on Soft Tissue Bruise Injury

Previous our study, in vivo impact test assuming human-personal care robot interaction was conducted using live porcine in order to evaluate soft tissue bruise injury tolerance. Subcutaneous hemorrhage was determined by observation of hematoxylin and eosin stained tissue. As a result, bleeding occurs at the part of adipose tissue and muscle. In this study, 3-dimentional finite element analysis were conducted on simple model consist of skin and soft tissue in order to clarify the occurrence mechanism of bruise injury. FE model imitated subcutaneous structure of porcine skin used in impact test. Analytical conditions were assumed to the experimental condition that bleeding occurs at the part of adipose tissue and muscle. As a results, the part of taking maximum first principal strain is good agreement with the bleeding point obtained by experiment. The experiments and analytical results show that possibility of bleeding will be occurred capillary failure at the part of local high strain.