The following software systems (Freeform Origami, Origamizer, Rigid Origami Simulator) are proprietary software provided under the following license.
The user is allowed to use the software if and only if both of the following conditions are satisfied. Before using the softwere, please contact me in advance.
(Non-Commercial Use) The use of the software is non-commercial.
(Attribution): The resulting works achieved using the software, e.g., research publications, exhibitions, educational workshops, etc. acknowledge the usage of the software and cite at least one of the following references.
Freeform Origami: reference ,, or 
Origamizer: , or 
Rigid Origami Simulator:  or 
Any other type of usage, e.g., commercial use, needs a separate permission. Please contact : tachi at idea.c.u-tokyo.ac.jp
上記に該当しない場合（営利目的利用など）をお考えの方は個別にご連絡下さい。：tachi at idea.c.u-tokyo.ac.jp
 Tomohiro Tachi, "Freeform Origami", www.tsg.ne.jp/TT/software/
 Tomohiro Tachi, "Generalization of Rigid-Foldable Quadrilateral-Mesh Origami," Journal of the International Association for Shell and Spatial Structures (IASS), 50(3), pp. 173--179, December 2009.
 Tomohiro Tachi, "Freeform Variations of Origami", in Proceedings of The 14th International Conference on Geometry and Graphics (ICGG 2010), Kyoto, Japan, pp. 273--274, August 5-9, 2010.
 Tomohiro Tachi, "Freeform Rigid-Foldable Structure using Bidirectionally Flat-Foldable Planar Quadrilateral Mesh", Advances in Architectural Geometry 2010, pp. 87--102, September 2010.
 Tomohiro Tachi, "Origamizer", www.tsg.ne.jp/TT/software/
 Tomohiro Tachi: "Origamizing Polyhedral Surfaces," IEEE Transactions on Visualization and Computer Graphics, 16(2), pp. 298-311, 2010.
 Tomohiro Tachi: "3D Origami Design based on Tucking Molecule," in Origami4, pp. 259-272, 2009.
Rigid Origami Simulator
 Tomohiro Tachi, "Rigid Origami Simulator", www.tsg.ne.jp/TT/software/
 Tomohiro Tachi: "Simulation of Rigid Origami ," in Origami4, pp. 175-187, 2009.
This software is a design software that allows users to interact with origami forms while altering the crease pattern of the model.
The software can keep:
Developability (foldable from a piece of paper)
Flat-foldability (foldable into a flat shape)
Planarity of facets (paper do not twist in 3D form)