Current Research | Biomimetics

Numerical Simulations on Bio-inspired Swimming Robots

By Ruoxin Li, Dr Qing Xiao

This research is a numerical simulation, based on the bio-inspired swimming robots: the Amphibot III. There are eight segments in the model, representing the fish backbone from the head to the tail. The desired shape motion is defined beforehand. Commercial software ANSYS Fluent 14.5 is used to carry out the calculation. To solve the motion problem for several different segments, the user defined function (UDF) in Fluent is used, which incorporates a multi-body dynamics algorithm. Two different groups of parameters are employed in order to imitate different fish locomotion. The vorticity contour is shown in both videos.

Further research on this problem, the anguilliform swimming is studied. By given analytical description, the width of fish body can be set to its length. The shapes of eight elements are changed in order to fit real anguilliform fish. As the lateral displacement of the mid-line is given, motions on the hinges can be curve fitted through dividing the fish length into 8 parts. Motions on all the joints are actuated. Animation is given as following. For the cases of passive joints, research will be carried out in the future.