# Can bellows make loops?

Can flexible polyhedron (hyperbolic or euclidean) have non-simply connected configuration space not containing singular polyhedra?

• Could you explain what the phrase "singular polyhedra" means? Thanks. – Joseph O'Rourke Jan 9 at 15:23
• Ones with angles between faces equal to $0$ or $\pi$. Without excluding that things you can easily find examples in $1$-dim polyhedra. – Denis T. Jan 10 at 6:56