Supraspinatus Tensile Data and Processing Files

Filename: TestData.xlsx
The data is test stress-strain data for cadaveric human supraspinatus tendon obtained in a uni-axial tensile test on MTS EM Tension testing equipment at University of South Africa's Biomechanics Research Laboratory. The equipment was operated in displacement mode on all the three tests at 0.1 s-1 of strain rate. The samples were not preconditioned. All columns are appropriately labelled to enable researchers to understand what each column represents. The test equipment did not have an environmental chamber at the time of the test so the samples were inevitably exposed to varying conditions before and during the test procedure.
Filename: Hyperelastic_vs_Viscoelastic_Nonlin_Modelling.m
This is a main processing MATLAB program file. It calculates the stress using nonlinear least squares curve fitting routine.
Filename: funTestData_ShoulderTendon.m
The function is called by the above file to fetch test data from the Excel file 'TestData.xlsx' and extracts only the section within the elastic region. There are three tests in the file and each test data is different in terms of the upper limit of the elastic region. The function calls each test data as specified in its argument.
Filename: funyehmod.m
This MATLAB function implements the Yeoh material model.
Filename: funstdnonlinsolid.m
This MATLAB function implements the standard nonlinear solid model using the sigmoidal kernel function.