Investigating Biomechanical Properties of A. tortilis as Related to their Habitat: A novel approach to characterize bending

ABSTRACT The biomechanical properties of Acacia tortilis were investigated considering its habitat (wild vs. nursery). The plant materials were collected from partially urbanized area in Doha city and from Qatar Foundation Nursery. The results show that Acacia grown in field are more flexible than those grown in nursery. Young’s Modulus of Elasticity was found to be 191 MPa and 617 MPa and the Flexural Modulus was found to be 49 MPa and 575 MPa and the breaking force was found to be 210 and 550 N for nursery and field Acacia, respectively. The deflection angle was measured using sensitive flex sensors connected to Arduino boards and was found to be higher for field Acacia (50°). Image processing techniques were used to mathematically describe the branch motion versus time diagrams. The plant part being investigated was covered with red tape and videotaped while subjected to a force causing it to bend. The stem was divided into 745 successive points and the change in their position with time taken frame by frame was converted into a change in position expressed through mathematical parameters. The bending movement of the branch was found to follow a power function H = (4001 ? e0.06m). HighlightField grown Acacia have higher values of Young’s and Flexural Moduli than nursery grown ones thus conferring them more elasticity and flexibility.