Element* contact_element = el->FindElement("contact");
while (contact_element) {
lGear.push_back(new FGLGear(contact_element, FDMExec, num++));
Element* contact_element = el->FindElement("contact");
while (contact_element) {
lGear.push_back(new FGLGear(contact_element, FDMExec, num++));