public void doControl() {
   contactModel.doContact();
 }
 public void addContactable(Contactable contactable) {
   contactModel.addContactable(contactable);
 }
 public void initialize() {
   contactModel.setKContact(200.0);
   contactModel.setBContact(10.0);
   contactModel.setFrictionCoefficients(0.5, 0.3);
 }
 public void addContactPoint(ExternalForcePoint contactPoint) {
   contactModel.addContactPoint(contactPoint);
 }