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Due to the efficient and flexible flight ability of bats, bat-like robots have become the focus of research in the field of bionic robots. Aerodynamic calculation is an important part of the research field of bat-like robot, which is the basis of the structure design and flight controller design of bat-like robot. However, due to the complex flight mechanism of bats, there is no mature theoretical method to calculate the flight aerodynamic force of bat-like robots. To solve this problem, this paper takes the membrane of a bat-like robot as the research object and analyzes in detail the effects of wing folding and unfolding and flexible deformation of the membrane on the chord length, passive torsion angle and relative velocity. Based on quasi-steady state model and blade element method, a set of aerodynamic calculation method for flexible deformed wing is established. In order to verify the effectiveness of the proposed method, the theoretical calculation results and the results of the fluid-structure interaction simulation are compared and analyzed under various working conditions. The two results are in good agreement under each working condition, and the errors are all within reasonable range, which proves the effectiveness of the method. This study can provide a theoretical basis for rational structure design and precise flight control of bat-like robot. [ABSTRACT FROM AUTHOR]

Adsorption behavior and dynamics of Arg-Gly-Asp (RGD) tripeptides with different orientations onto the rutile TiO(2) (110) surface in water solution were systematically investigated by molecular dynamics (MD) simulations, using two different water models, TIP3P (transferable intermolecular potential 3P) and SPC/E (extended simple point charge). Possible RGD-TiO(2) binding modes in the form of hydrogen-bonding interactions, involving the amide groups (NH(3)(+) or NH(2)(+), NH(2)) and surface oxygen atoms were identified. The behavior of RGD in contact with the TiO(2) layer was elucidated in detail by the analysis of atom-atom distances, backbone dihedral angles and hydration layers distributed over the interface. The simulation results suggest that, the attachment modes of tripeptides with the same starting arrangement are similar when solvated in TIP3P and SPC/E water, but the conformational stability of the amino sequence is somewhat sensitive to the adopted solvent model. Moreover, the intensity of peptide-surface interaction varies widely depending on the initial arrangement of the RGD sequence.