“…Numerous collision detection frameworks using different methodologies have been reported for both photon and proton external beam therapy. 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 In general, the treatment head (gantry) and the patient support (table or chair) are modeled with varying degrees of details, that is, from a simple set of connected vertices to actual computer‐aided design files. 18 , 26 , 27 , 31 The patient has also been represented by a simple geometry like an ellipse 17 or a column, 32 , 33 or skipped for simplicity.…”