The coefficient of restitution(COR)is one of the fundamental particle properties needed in the set up of discrete element modelling (DEM) simulations.The more accurate the input parameters for DEM are, the more accurate the resulting simulation outputs will be. The determination of the COR for spherical particles is a relatively straightforward process, however, when considering irregular shaped particles, the unpredictable behaviour of particles after impact makes the analysis of the COR more involved.This
paper presentsanexperimentalmethodtodeterminetheCORusinghigh-speedvideoinathree-
dimensional environmenttocapturetherandombehaviourofirregularshapedpolyethylenepellets.The
angular displacementandangularvelocityofparticlesareexperimentallydeterminedandtheprocess
used todeterminethecoefficient ofrestitutionusingvariousequationsispresented.