Speaker:Prajjwal Jamdagni

Modeling of Fruit and Vegetable Cutting Based on Fracture Mechanics and the Finite Element Method

Automation of food preparation is highly desirable in the kitchen as well as in industry due to the repetitive and tedious nature of the task and the increasing demand for hygiene and safety. To realize cutting skills such as chopping and slicing and to optimize its effort, a cutting robot needs to estimate the knife’s interaction forces with the object and cutting board, and to track the crack propagation and deformation. We present a physics-based model for cutting deformable objects that draws upon fracture mechanics and the finite element method (FEM). To avoid the high computational expense of a 3D mesh model due to its requirements for tiny elements surrounding the knife’s edge, we leverage the problem’s plane strain nature to divide the object into several cross sections normal to the edge so 2D meshes can be employed. A formal analysis has been performed to quantify the reduction in effort due to slicing, revealing the dependence of fracture toughness on the Poisson’s ratio and the direction of the knife’s velocity. The effect of the knife’s geometry is also modeled in the context of predicting the interaction forces. In the next phase, we plan to combine the above work with the real-time estimation of the object’s physical properties for optimization of the cutting trajectory.

Committee: Yan-Bin Jia (major professor), Jin Tian, Tichakorn Wongpiromsarn, Ashraf Bastawros, and James Oliver