Dear Getfem-Users, I am trying to impose a rolling condition on a "tire". My work is directly inspired from the "Example of wheel in contact" tutorial <https://getfem.org/tutorial/wheel.html>. In this tutorial, one wants to prescribe the rim rigidity and the vertical force. From this, I just have to add a rolling condition. Specifically I want to find the rotation speed "alpha_rot" that enables me to impose some force Fx:
gwfl_rot='-lambda_D.Test_u + ([cos(alpha_rot*time),sin(alpha_rot*time);-sin(alpha_rot*time),cos(alpha_rot*time)]*(X-[0;y_c])-(X-[0;y_c])\ + [speed*time;alpha_y] - u).Test_lambda_D +(lambda_D.[1;0] + Fx)*Test_alpha_rot + 1E-6*alpha_rot*Test_alpha_rot' gwfl_y='(lambda_D.[0;1] + Fy)*Test_alpha_y + 1E-6*alpha_y*Test_alpha_y' roll_gwfl=gwfl_y+gwfl_rot idBrick = model.add_nonlinear_term(mim, roll_gwfl, HoleZone) Where alpha_rot and alpha_y are the "parameters" I am trying to find. This works for up to ten timesteps but then it diverges... I tried to use two multipliers instead of one which leads to worse results. Am I on the right track ? Is there a better way to achieve this ? Thanks in advance, Best regards, Raphaël
