  This paper presents an automatic finite element simulation scheme accounting
for high geometric nonlinearity and the difference between linear and nonlinear
buckling of composite thin-walled lenticular tubes (CTLTs). Parameterizing of
cross-section shapes and generation of design space for CTLTs with both
circular and parabolic arcs were accomplished, and several key factors were
identified, in particular the contrary effect of lumbus length and parabolic
coefficient on the bending stiffness anisotropy. The first quantitative
comparison of triangular rollable and collapsible (TRAC) booms and CTLTs is
given in terms of bending performance in two directions, showing that the
optimal CTLT carefully selected from the design space demonstrates a comparable
or even better performance than the TRAC boom. This is of great importance from
both academic and engineering perspectives. Our efforts enhance the
understanding of nonlinear buckling and post-buckling behavior of CTLTs, and
provide guidelines for future design of CTLTs with desirable performance.
