Biohydrodynamics Toolbox To BhT's home page  

Demos gallery


This page presents a collection of examples realized with the Biohydrodynamics Matlab Toolbox.
For each example, you can merely play the movie by clicking on the picture or copy-past the DAT-File together with all of the other required additional files and redo the complete experiment by your own.

January, 2009

Ellipse-shaped solid in a filled box

  • The DAT-File.
  • Comments: the solid's density is larger than the fluid's so it falls and collides with the bottom of the box. Since the overall energy is conserved, the solid goes on colliding after its first bounce.
Movie

Images/ellipse_in_a_box.jpg
Set of solids colliding

  • The DAT-File.
  • Comments: blue solids'  density is larger than the one of the fluid and red solids' is smaller. Red and blue collide half-way.
Movie

Images/six_ellipses.jpg
Two Star-shaped solids and an ellipse

  • The DAT-File.
  • The boundary M-File for rounded star description
  • Comments: two star-shaped solids collide first against a fixed ellipse then together (see Tutorial #2 in BhT's documentation).
Movie


Images/two_stars.jpg
A first simple fish

Movie

Images/firstfish.jpg
The bodies hydrodynamically decoupled hypothesis

  • The DAT-File.
  • Comments: how two distant ellipse-shaped solids reciprocally impact each other. Under the classical hydrodynamically decoupled hypothesis, both trajectories would have been straight lines!
Movie


Images/hydro_decouple.jpg
Free fall of an ellipse

  • The DAT-File.
  • Comments: The blue ellipse is neutrally buoyant. The density of the red ellipse is greater than the fluid's. It falls and drags the blue one down.


Movie
free_fall.jpg
Two fishes crossing

  • The DAT-File.
  • The controls M-File.
  • Comments: Two fishes swim one toward the other and cross. One more time, computations are done without the bodies hydrodynamically decoupled hypothesis.
Movie


two_fishes


March, 2009 

New: BhT version 1.5 (June, 2009) will support deformable bodies.

Model of swimming amoebae

  • The amoebae is neutrally buoyant. 
  • The colors give the density inside the amoebae: some areas of the amoebae's body are compressed while others are stretched.
  • The black spot is the position of its center of mass.
Movie
Images/s_motion_image.jpg
Amoeba following a squared trajectory

  • Same model as the preceeding one but the shape-changes cause the amoeba to move along a square.
Movie

Images/square_course_image.jpg
Model of amoebae swimming along a circle

  • The amoeba can actually swim along a circle of any radius.
Movie
Images/circle_course_image.jpg
Real time control and simulation of the amoeba

Click here and copy-paste the m-File.
Run it and use the keys: 'P' and 'L' to modify the velocity, 'W' and 'X' to steer, and 'G' to enable or disable the grid.
game_amoeba.jpg

May, 2009


Swimming with non zero mean thrust ?

Is a fish swimming in an ideal fluid able to generate a non zero mean thrust ? 
  • no when the fish is alone in the fluid (no obstacle neither other body) as in movie 1. The fish stops  dead as soon as it stops moving.
  • yes in the other cases (example here with two obstacles in movie 2). 
Movie 1
Images/fish_no_obstacle.jpg
Movie 2
Images/fish_obstacles.jpg
           
 

2008 - A. Munnier and B. Pincon (Insitut Elie Cartan and INRIA Lorraine, Projet CORIDA, Nancy, France).