nyu future reality lab · tei ’25 · bordeaux

robotecture

The 3x3 Robotecture prototype without its fabric, on wooden legs: white printed units joined by beams, the middle units raised and the outer ones lower, with servo wires hanging between them

a surface that lifts itself. a grid of small robots, joined by beams, under one continuous skin.

units
3 × 3
motors
18
cost
≈ $300
drive it

01

see it move

the prototypes as a table, a bed, a roof, a storage box and a vr terrain.

play the film

02

a reshaping surface

a surface is the simplest thing in a building. what if it could reshape itself into whatever the room needs?

actuators,beneath

pin-based displays

Each pin is pushed from below, so the actuators fill a base under the surface. Dense and precise, but the space underneath is taken.

open space under the surface

robotecture

The units lift themselves by turning the beams between them, so the whole mechanism is one flat layer. The space on both sides is free, and objects can pass through the gaps.

03

drive it

the 3 × 3 prototype, at its real proportions: 20 cm cells, two motors in every unit, a fabric skin on top. pick a scenario, or grab a unit.

the real onethe 3 × 3 skeleton, without its skin, changing shape

a model of the prototype: heights move at the servos’ pace (any shape in about 1.3 s, as measured), and no unit can rise more than one cell above a neighbour, because the beams stop at 45°. The angles come from the paper’s equation. Where a beam reaches that limit it turns orange.

04

how a unit lifts itself

one line of the grid, in section. a motor turns the joint between its two beams; the beams push against the neighbours, and the unit rises. drag a unit.

for the selected unit

a
b
c
l
20.0

α₁ = atan( l ⁄ (b − a) )

α₂ = atan( l ⁄ (b − c) )

α = α₁ + α₂

heights in cm. The motor turns its joint to α. 180° is level; the mechanism allows 90° to 270°, so a unit can never be more than one cell (20 cm) above or below a neighbour, and its full range equals its distance to the frame. The beams telescope as the angle changes: watch their lengths.

Rendering of a Robotecture unit: assembled at rest and lifting, and exploded into its parts, lettered a to h

05

three units, one design

simple, efficient, robust: each round removed something.

  1. The first prototype: a white printed sphere with four beams

    v1 · overlapping joints

    a sphere

    Four beams met at the centre of a sphere, guided by a ring gear inside it. Elegant from outside, but the printed PLA sphere deformed within days, and the crowded inside left no room for strong motors.

  2. The second prototype: a boxy printed unit with beams staggered in two layers

    v2 · independent layers

    beams in layers

    Beams from the two directions stacked in different layers, with no ring gear. It worked, but it was fragile. One version put a camera on every unit, so people could “grab” a unit in the air and pull it up or down.

  3. The third prototype: a stronger frame-like chassis on a grid

    v3 · the final unit

    stronger, simpler

    A stiffer chassis, larger MG996R motors, lighter and stronger beams, and upgraded power and frames: stable enough to grow into larger grids.

06

like lego, at room scale

every unit is identical. add one by joining its beams to the grid; the frame is built from modular parts too.

Drawings of a 2x2 and a 3x3 grid on their frames, and the 2x2 exploded into units, beams, rods and printed joints, with a detail of a corner joint being assembled
The 3x3 prototype on its wooden frame and legs, without fabric
3 × 385 × 85 cm, on legs
A 2x2 and a 1x2 standing on their sides at an angle, like two walls
2 × 2 and 1 × 2standing, as walls

control

a laptop computes the shape and the angles; an arduino sends them to eighteen servos.

Applications run in Unity and WebXR. Over serial, an Arduino UNO receives each unit’s height and drives the motors through two 16-channel PCA9685 boards. A 12 V, 50 A supply feeds two 6 V, 25 A converters and the distribution boards.

laptopunity · webxr arduino unoheights → angles pca9685 × 216-channel pwm mg996r× 182 per unit 12 V · 50 Asupply 6 V · 25 A × 2converters distributionboards seriali²cpwm signalpower

07

by the numbers

measured on the prototypes.

one unit weighs
218g
one unit lifts
1kg
height range
±20cm
any shape in
1.3s
motor torque
1.47N·m
cell
20cm
per unit
<$25
3 × 3, all in
≈$300

what a unit costs

printed chassis, bases, tubes
$10
2 × MG996R servo
$9
wooden beams
$1
one unit
under $25
Arduino, power, wiring
$60
outer frame
$30
3 × 3 system, 85 × 85 cm
≈ $300

how much each unit can carry

Max load in kg, measured on the 3 × 3. Every unit lifts itself, so the outer units also carry the inner ones: the centre bears least.

0.4 0.6 0.8 kg

Estimated for larger grids, from the torque balance: about 0.4 kg at the centre of a 4 × 4, 0.26 kg for a 5 × 5.

08

what it becomes

enclosures, surfaces you touch, and objects it handles: the scenarios built with the 1 × 2, 2 × 2 and 3 × 3 prototypes. most can run on the model above.

aarchitecture: enclosures that adapt

  1. The roof shaped into a dome over a small stage, with sound arcs drawn on

    opera house

    The ceiling rises into a dome to reflect the singer’s voice to the audience.

  2. A ceiling node lowering toward a figure, with arrows

    a ceiling within reach

    The node holding a broken light bulb comes down to be changed; the same for paintings or anything stored overhead.

  3. A roof with black solar panels tilting toward a drawn sun

    solar roof

    The roof follows the sun’s direction, so its panels collect more energy.

  4. Blue beads gathered in a dip in the middle of the roof, with arrows toward it

    rain collection

    When it rains, the roof dips in the middle and gathers the water. Beads stood in for rain.

  5. A fabric wall in a model room bending away from a wooden figure to give it more space

    a wall that moves

    A 1 × 2 standing as a wall between two rooms: it recedes from the occupied room to give it more space.

bsurfaces you touch: furniture and haptics

  1. A person sitting at the fabric-covered table, the surface raised under an open book

    reading table

    Put a book on it, and the table lifts a slope under it for easier reading.

  2. A teddy bear and an alarm clock on the fabric surface, raised behind the bear like a chair back

    a bed that wakes you

    When the alarm rings, the bed folds into a chair and sits you up. With pressure sensing, it could fit the body it holds.

  3. A toy car on a mountain road projected onto the shaped fabric

    terrain, projected

    A mountain road for a toy car: the surface makes the hills, projection mapping paints them.

  4. A person in a VR headset touching the shaped surface, with a rocky landscape projected on it

    touch in vr

    A rocky landscape in VR, shaped in the room: the hand finds the rocks where the eyes see them.

cobjects it handles

  1. A ball rolling down the tilted fabric toward an open hand

    to your hand

    The surface tilts and the ball slides toward the hand that waits for it.

  2. A ball pushing up through a slit in translucent fabric over the grid

    storage that hides and reveals

    A 7 cm ball rests below the surface. When the beams lower, the slit in the fabric opens and the ball comes up through it; push it back down to hide it.

  3. A marble maze on the grid with a blue ball, and a phone used as a remote control

    a maze, from far away

    Over a network, a phone tilts the surface to roll a ball: tangible telepresence.

09

limits, and what’s next

what the prototypes taught, from the paper’s discussion.

  1. height

    The range is bound by the grid, and neighbours can never meet at a right angle. An origami-like unit could fold a floor up into a wall.

  2. weight and sag

    Self-lifting puts the most load on the outer units, and small play in every joint adds up as a sag at the centre. Smaller grids joined by rigid frames keep their strength; standing a grid upright puts the weight on the beams instead.

  3. resolution

    The MG996R sets the size of a unit. Smaller servos would make a denser grid, but a weaker one: Robotecture is meant for tables and rooms, not hand-held displays.

  4. sensing

    It shapes, but does not yet feel. Torque sensors on the motor shafts could let it read a push, or the shape of an object pressed into it.

the upgradeRDS5180 servos with aluminium or carbon-fibre beams: by the paper’s estimate, 1.2 kg at the centre of a 10 × 10 grid, for about $80 a unit.

10

tei ’25, bordeaux

Yuhan Wang presenting Robotecture at a lectern on the TEI 2025 stage, a slide about the sparse grid design behind

As first author, I presented the paper at TEI 2025, the International Conference on Tangible, Embedded and Embodied Interaction, in Bordeaux.

TEI is a leading conference in human-computer interaction for tangible and embodied interaction. It brings together new research from academia and industry on interaction design, hardware prototyping and immersive experience.

Yuhan Wang, Keru Wang, Zhu Wang and Ken Perlin. 2025. Robotecture: A Modular Shape-changing Interface Using Actuated Support Beams. In Nineteenth International Conference on Tangible, Embedded, and Embodied Interaction (TEI ’25), March 4–7, 2025, Bordeaux / Talence, France. ACM.

read the paper (pdf)doi.org/10.1145/3689050.3704925 ↗

time
2023–2024
lab
Future Reality Lab, Courant Institute, NYU
team
Yuhan Wang, Keru Wang, Zhu Wang*, Ken Perlin* * equal advising
published
TEI ’25, ACM