Think globally, fit locally: unsupervised l earning of non-linear manifolds
A construction member having a tubular body with side walls surrounding a passage through the body. Each side wall has an opening and a plurality of notches for accommodating a connecting element. The side walls have a longitudinally projected flange of a size that fits into a passage of another construction member so that a plurality of construction members can be connected together. The body can have a square, triangular, and other multiside shapes.