Modelling and experimental investigation of capsule-tumour contact for early bowel cancer detection

Tissue's mechanical properties, such as stiffness, are critical biomarkers that could be utilised to detect early stages of malignant transformation and distinguish between healthy and abnormal tissues. This paper studied a new method by using a capsule robot to evaluate the stiffness of bowel tumour for early bowel cancer detection and staging. Hertz contact theory was used to model capsule-tumour contact in an intestinal environment. Both lateral and vertical contacts were performed with finite element (FE) and experimental validations. Young's moduli of bowel tumours obtained by the proposed models were applied to FE models and then generated force-displacement curves to compare with experiments. Our comparative analyses show that FE results are in good agreement with experimental results. The proposed method can be potentially used in real time for detecting early bowel cancer by using a capsule robot when self-propelling in the bowel.