We propose a new design of complex self-evolving structures that vary over time due to environmental interaction. In conventional 3D printing systems, materials are meant to be stable rather than active and fabricated models are designed and printed as static objects. Here, we introduce a novel approach for simulating and fabricating self-evolving structures that transform into a predetermined shape, changing property and function after fabrication. The new locally coordinated bending primitives combine into a single system, allowing for a global deformation which can stretch, fold and bend given environmental stimulus.

3D printing has captured the imagination of everyone from industry experts to at-home hobbyists.However, there are significant challenges that need to be addressed in order for 3D printing to have widespread adoption in construction and manufacturing. A new category of printing has recently been introduced, called 4D printing, which describes the ability for a material system or object to change form and/or function after printing. 4D printing offers a number of unique advantages over 3D printing that may prove to be the critical capability needed to catalyze widespread implementation. This paper attempts to go beyond existing capabilities in 4D printing to create precise and universal folding techniques that approach a wider range of applications through a series of radically new physical models. A number of physical and digital prototypes demonstrate major advances in 4D printing, including: custom angle-structures that can transform from any one shape into another rigid 3D structure, curved-crease origami for doubly curved surfaces and dynamic fields utilizing surface curling and gradient material distribution.

The basic motion-planning problem is to plan a collision-free motion for objects moving among obstacles between free initial and goal positions, or to determine that no such motion exists. The basic problem as well as numerous variants of it have been intensively studied over the past two decades yielding a wealth of results and techniques, both theoretical and practical. In this paper, we propose a novel approach to motion planning, hybrid motion planning, in which we integrate complete solutions along with Probabilistic Roadmap (PRM) techniques in order to combine their strengths and offset their weaknesses. We incorporate robust tools, that have not been available before, in order to implement the complete solutions. We exemplify our approach in the case of two discs moving among polygonal obstacles in the plane. The planner we present easily solves problems where a narrow passage in the workspace can be arbitrarily small. Our planner is also capable of providing correct nontrivial "no" answers, namely it can, for some queries, detect the situation where no solution exists. We envision our planner not as a total solution but rather as a new tool that cooperates with existing planners. We demonstrate the advantages and shortcomings of our planner with experimental results.

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