Prototyping with 3D printing depends heavily on virtual modeling, which requires expertise and often leads to scale mismatches and inefficient iteration. Physical deformation through heating is possible but challenging, as heating is difficult to control and deformation remains complex. We introduce TF-Shell, a thermoformable shell that enables repeatable, localized thermoforming of 3D-printed prototypes. Leveraging shape-memory properties, TF-Shell allows 3D-printed objects to achieve volumetric deformation, restoration, and shape memorization within the physical prototyping process. With customizable features, it can be embedded into free-form models through a design tool. A user study shows that TF-Shell provides intuitive, convenient physical modification and expands iteration beyond virtual modeling. Technical evaluations confirm its thermoformability and repeatability, establishing TF-Shell as a practical approach for integrating physical deformation into 3D printing workflows.

This article introduces Rolling Pixels, that are essentially robotic Steinmetz solids, for constructing frame-by-frame physical animations. As a bicylinder-shaped Rolling Pixel rolls back and forth or left and right, the shape and color of the top view of the pixel changes repeatedly without using any additional shape- or color-changing techniques. Implemented using off-the-shelf products and technologies, Rolling Pixels are easy-to-build, reproducible, and customizable kinetic design material. We describe the design and implementation of the current prototype of Rolling Pixels. We also illustrate the potential of the Rolling Pixels as building blocks for physical animations through a set of simulated examples.