Massachusetts Institute of Technology

Chin-Yi Cheng

Hiroshi Ishii

Jifei Ou

Lining Yao

Daniel I Wang

Clark Della Silva

Guanyun Wang

Helene Steiner

Gershon Dublon

Liang Zhou

Wen Wang

A computer produces a digital model that efficiently describes a dense array of many micro-pillars. The digital model achieves this efficiency by describing an entire micro-pillar with only a few parameters. For example, an entire micro-pillar may be described by two of more of the following parameters: height, base thickness, profile and tilt. The computer outputs instructions to fabricate the micro-pillar array, in accordance with the digital model. A 3D printer fabricates the micro-pillar array, based on the instructions. Applying vibration to a directional array of micro-pillars may cause the array of micro-pillars to actuate motion of a passive object that is touching the array. Also, a sensor may measure sounds caused by swipes against a micro-pillar array, and output signals indicative of the measurements. A computer performs a machine learning algorithm that takes the measurements as an input, and classifies the swipes.

Micro-pillar methods and apparatus

A composite film includes a substrate that is not responsive to relative humidity, and also one or more layers of hygromorphic material. The hygromorphic material expands in response to an increase in relative humidity and contracts in response to a decrease in relative humidity. In some cases, the composite film is bi-layer or tri-layer. The composite films are fabricated such that they undergo a desired bending pattern in response to changes in relative humidity. In some cases, these bending patterns are combinations of two bending primitives: a smooth curve and a sharply angled curve. These two primitives are combined to create a variety of shape transformations including 1D linear transformation, 2D surface expansion and contraction, 2.5D texture change and 3D folding. Any type of hygromorphic material may be employed, including living gram positive and gram negative bacterial cells, yeast cells, plant cells, mammalian cells, cell debris, or hydrogel.

Methods and apparatus for hygromorphic shape control

Growing community of inventors

Cambridge, MA, United States of America

Chin-Yi Cheng