Deformation characteristic of tea shoot under moving negative pressure guidance: Numerical simulation using an improved IB-LBM

To address the challenge of mechanized picking of famous tea, this study proposes a numerical framework based on an improved immersed boundary-lattice Boltzmann method (IB-LBM) to characterize tea shoot motion and deformation under moving negative pressure guidance. The influences of descent speed V , horizontal deviation W , and rotational stiffness k on tea shoot deformation are quantitatively investigated. No universal fixed picking thresholds are available, as picking boundaries are strongly dependent on the mechanical properties of tea shoots. Under the tested working conditions of the two-dimensional numerical framework, the proposed method achieves good agreement with experimental measurements, with the maximum relative error of deformation magnitude being 6.16%. This work clarifies the key influencing factors of dynamic negative pressure guidance and provides model-specific references for the parametric design of tea picking end-effectors. It also extends the application of the IB-LBM method in agricultural fluid-structure interaction simulations.