How do you optimize body structure for stiffness while minimizing weight?

Stiffness optimization involves: Topology optimization identifying efficient load paths, closed-section design for torsional efficiency, strategic reinforcement placement at high-stress nodes, material selection matching properties to local requirements (high-strength steel in critical areas), beading and embossing patterns increasing panel stiffness without mass, joint design maximizing stiffness transfer, and avoiding stress concentrations. CAE tools analyze mode shapes and identify areas contributing most to stiffness; design changes are evaluated for stiffness-to-weight efficiency ratio. The goal is meeting stiffness targets with minimum mass addition.