Contact modeling and parameter switching for simultaneous reproduction of rheological force and deformation

Rheological objects, such as some human organs or tissues, various food products, and cloth, demonstrate complex deformation behaviors, which consist of both elastic and plastic properties. Due to the presence of residual deformation, modeling of rheological objects is a challenging work, especially simultaneous reproduction of both rheological force and residual deformation. This paper presented an FE model for simulating rheological objects. This model involved a parameter switching strategy which could result in accurate simultaneous reproduction of both rheological force and deformation behavior. Contact modeling between a rheological object and an external instrument was investigated and it provided a good criterion for parameter switching strategy. Experimental results with Japanese sweets material were then presented to validate the FE contact model and parameter switching strategy. Simulation results of semi-circular and circular objects were also presented to demonstrate the ability of our contact model and parameter switching strategy for dealing with irregular shaped objects.