Featured Research

Surface-Based Manipulation with Modular Foldable Robots

Intelligence lies not only in the brain but in the body. We present surface-based manipulation strategies that diverge from classical grasping approaches, using flat surfaces as minimalist end-effectors. By adjusting surfaces' position and orientation, objects can be translated, rotated, and flipped using closed-loop control — adapting to objects of various shapes, sizes, and stiffness levels.

Ziqiao Wang*, Serhat Demirtas*, Fabio Zuliani, Jamie Paik
npj Robotics, vol. 4, no. 1, 2026 — Read paper on npj Robotics

Concept: Surface vs. Grasping

Figure 1: Surface-based manipulation concept — grasping vs surface-based strategies, translation, flipping, rotation, and food packaging application

Surface-based manipulation: (a) Grasping vs. surface-based intuition, (b-d) Translation, flipping, and rotation strategies, (e) Food packaging application concept

Rigid Object Manipulation

Translation + 180° flipping of a rigid block — coordinated motion of two surface modules

Rotation to multiple target angles (20°, 30°, 60°, 80°) via coordinated roll and height adjustment

Soft Object Manipulation

Closed-loop translation of a soft, randomly shaped Play-Doh object from multiple initial positions to a target

Shape manipulation — fold-translate-refold sequence transforms a soft strip into a rolled configuration

Heterogeneous Object Manipulation

A slippery fish — surface-based support from below, no grasping needed

Live conference demonstration — manipulating dough on the surface platform

Surface-based manipulation of rigid objects, soft deformable objects, and heterogeneous objects including cookies, plush toys, tape rolls, and food packages

Full overview — (a) Rigid: solid block. (b) Soft: deformable slime, particle-filled slime. (c) Heterogeneous: cookies, plush toys, cake packages, tape rolls, popcorn

Robot Design

3D rendering of the surface-based manipulator showing top surface, origami legs, BLDC motors, connectors, and base platform

3-DOF surface module — acrylic top surface on origami-inspired legs with BLDC motor actuation

Manufacturing process: design, laser cut, heat press, final cut, assembly; layered structure of glass fiber, adhesive, and polyimide

Manufacturing process — FR4 and polyimide layered origami legs, laser cut and heat pressed

Control & Validation

Control architecture: high-level controller with vision system, task planner for translation/rotation/flipping, and motor controller

Control architecture — vision-based closed-loop control with task planner for translation, rotation, and flipping

Experimental validation of translation and flipping with position/yaw tracking, and rotation to multiple target angles

Experimental validation — translation + 180° flipping, and rotation to 20°/30°/60°/80° targets

Key Contributions

Introduced surface-based manipulation as an alternative to grasping — using flat surfaces as minimalist end-effectors
Three manipulation primitives: translation (via coordinated pitch/roll/height), flipping (dynamic 180° reorientation), and rotation (Z-axis reorientation)
Modular foldable robot platform with origami-inspired legs, 3-DOF per module
Closed-loop vision-based control enabling reliable manipulation of rigid, soft, deformable, and heterogeneous objects
Shape manipulation of free-form objects through multi-step fold-translate-refold sequences
Demonstrated on diverse objects: blocks, slime, cookies, plush toys, cake packages, tape rolls, popcorn bags

Published in npj Robotics, 2026 · EPFL Reconfigurable Robotics Lab

← Back to all projects