Roombots

Modular robotics for adaptive and self-organizing furniture

Article in Robotics and Autonomous Systems (May 2020):

Roombots extended: Challenges in the next generation of self-reconfigurable modular robots and their application in adaptive and assistive furniture (DOI: 10.1016/j.robot.2020.103467, preprint)

In this article, we show improvements of the Roombots hardware as well as a series of proof-of-concept experiments demonstrating how the Roombots modules could be used as assistive and self-assembling furniture. In particular, we demonstrate autonomously moving furniture,  self-reconfiguration with 12 modules (36 degrees of freedom in total), object manipulation and gripping capabilities, human-module-interaction and the development of an easy-to-use user interface.

See the video below, and a nice article in IEEE Spectrum.

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Previous paper

A Hardware Perspective on 3D Self-Reconfiguration and Locomotion with a Homogeneous Modular Robot, accepted in Robotics and Autonomous Systems, July 2014, Online here: http://www.sciencedirect.com/science/article/pii/S0921889013001632

See the released Roombots EPFL Youtube video.

This project funded by the Swiss NCCR in Robotics explores the design and control of modular robots, called Roombots, to be used as building blocks for furniture that moves, self-assembles, and self-reconfigures. Modular robots are robots made of multiple simple robotic modules that can attach and detach (Wikipedia: Self-Reconfiguring Modular Robotics). Connectors between units allow the creation of arbitrary and changing structures depending on the task to be solved. Compared to “monolithic” robots, modular robots offer higher versatility and robustness against failure, as well as the possibility of self-reconfiguration. The type of scenario that we envision is a group of Roombots that autonomously connect to each other to form different types of furniture, e.g. stools, chairs, sofas and tables, depending on user requirements. This furniture will change shape over time (e.g. a stool becoming a chair, a set of chairs becoming a sofa) as well as move using actuated joints to different locations depending on the users needs. When not needed, the group of modules can create a static structure such as a wall or a box. Our dream is to provide multi-functional modules that are merged with the furniture and that lay users and engineers can combine for multiple applications.

The type of applications of such robots could be multiple: assistive furniture for the elderly or for people with a motor handicap, programmable conference rooms, interactive art, satelite or space station elements, etc. We are particularly interested in the first application, namely providing assistance to the elderly. Thanks to a SNF grant starting in September 2014, we would like to design multifunctional and assistive robotic furniture that can interact with users, help them recover from a fall, monitor their health, help them transfer between different positions (laying/sitting/standing), help them manipulate objects, and move away from or closer to the user depending on his/her needs.This work will be done in collaboration with the CHILI lab and with DomoSafety.

Our article in Robotics and Autonomous Systems (July 2014) presents an important milestone in the project. In particular we were able to demonstrate the following important basic functionalities of the Roombots:

• off-grid locomotion, i.e. free locomotion in the room
• going from off-grid to on-grid
• on-grid locomotion, i.e. moving on a grid of connectors thanks to sequences of attachments and detachments
• on-grid locomotion with collaboration between modules (e.g. one module helping the other to go over a corner)
• (simple) object manipulation for constructing pieces of furniture.

 See movies and pictures below.

Pictures

Copyright of pictures and videos: see the end of this page. Click the pictures to view a larger version.

Rendered vision of a table being assembled by Roombots (RB) modules, using lightweight elements and integrated RB modules.

Left: a Roombots module. The lower frontal connector is a fully equipped, active connection mechanism. The upper frontal slot is equipped with a passive connector plate. Right: rendered exploded view of a Roombots module.

Top-left: Roombots modules coming out of a storage box. Bottom-left and right: illustration of plug and play capabilities of Roombots modules.

A snake-like structure made of Roombots modules.

Concepts of application scenarios: (top) assistive apartment, (middle) Kindergarten, and (bottom) terrace. Images created by Augustin Mercier.

Chair from 12 RB modules. Typical office chair for size comparison included.	Table from RB modules and L-shaped passive pieces.	RB stool from 8 RB modules.
Miniature-table from 8 RB modules and 4 plates.	Coffee table from 8 RB modules and passive pieces.	Stool from 12 RB modules and passive pieces.
Rendered examples of furniture pieces made of either Roombots modules only, or mix of Roombots modules and passive elements. These passive elements are used to enhance structural integrity, and decrease complexity and weight. The black office chair, the stool, and the lamp are included for size comparison.

Movies

Selected movies of Roombots hardware

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Overview of the Roombots project

Roombots hardware

Locomotion of a quadrupedal structure

Roombots moving a small table

Roombots reconfiguration – From tripod to snake

Selected movies of Roombots optimization

RB fast learning

Matching simulation and reality

Optimal hybrid gaits for several morphologies

RB car

Selected movies of Roombots reconfiguration

Reconfiguration and locomotion of a roombots structure		Passive plates handling		RB Meta-module to quadruped		RB building up back chair
Reconfiguration of a chair and falling apart		RB trot table		Intelligent User Interface for Roombots

Collaborations

Experimental design studio

Design studio led by Laurent Massaloux and Simon Henin from Ensci Les ateliers (École nationale supérieure de création industrielle) in collaboration with EPFL+ECAL lab.
The studio aims to develop application scenarios using Roombots, in which the robots interact with existing objects and humans. An important part of the study was linked to creating passive accessories that could be manipulated by Roombots.
The results of this study were presented at Futur en Seine in June 2013.

Roombots Gardener from Anthony Loeuk on Vimeo.

Kyrielle [ENSCI] from Matthieu Ruthy on Vimeo.

Research overview

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Specifications of a single Roombots module
Overall dimensions	110x110x220 mm (4.3″x4.3″x8.7″)
Weight	1.4 kg (3.1 lb)
Degrees of freedom	3 (continuous rotational)
Number of connection ports	10 (active or passive)
Active connection type	4-way symmetrical gender-less mechanical latches
Energy source	4-cell LiPo battery, 1200 mAh. Autonomy ~1 hour
Communication	Bluetooth
Outer motors	Faulhaber 2342 012 CR
Inner motor	Faulhaber 2232 012 SR
Outer gearboxes reduction	305:1 (custom made)
Inner gearbox reduction	366:1 (custom made)
Outer dofs specs	26.6 RPM (no load), 4.9 Nm (nominal)
Inner dof specs	19.4 RPM (no load), 3.6 Nm (nominal)

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Development of the hardware modules

The first objective of this project is to develop modular robot prototypes of Roombots suitable for the scenarios described above. Each module has its own actuated joints, controller, and battery. Mechanical connectors allow rapid and solid attachment and detachment mechanisms between modules. Different types of sensing and communication abilities are being explored.

Control of locomotion of multi-unit Roombots

The second objective of the project is to develop novel methods for the adaptive control of movement and locomotion of multi-unit Roombots structures. The controllers should be capable of learning efficient types of locomotion for robot structures that are unknown a-priori and that change over time. We are exploring the use of distributed coupled nonlinear oscillators combined with optimization algorithms. The challenge is to find local interaction rules that optimize the global behavior of the group of modules, and that are sufficiently rapid to be carried out online.

Control of self-reconfiguration

The third objective is to design self-configuration algorithms for the generation of particular multimodule structures (e.g. stools or chairs), and to transform a structure A into a structure B. A transformation is performed through a sequence of motor actions, as well as attachments and detachments. We are currently developing planning algorithms that use metrics to measure the distance between structures, as well as heuristics to search for sequences of actions to reach a specific desired structure.

Robot-user interface

The fourth objective is to design a user-robot interface to allow users to guide, control and teach a group of modules. We aim at interactions that are high-level and easily learnable by non-expert users (i.e. general guidance rather than programming), using state-of-the-art mobile interfaces, tactile interactions with the modules, as well as a web interface. We are currently exploring a solution that combines gesture recognition using Kinects and augmented reality on iPads.

Involved People

This project is jointly done between CHILI lab and BioRob.

Past members: Stephane Bonardi, Massimo Vespignani, Rico Moeckel, Alex Sproewitz, Soha Pouya, and Masoud Asadpour.

Active and past collaborations: DomoSafety, EPFL+ECAL lab, ENSCI – Les Ateliers, Equimodus, and LASA

Funding

This project was funded  by the Locomorph project and by the Swiss NCCR in robotics. Preliminary studied were funded by Microsoft Research Cambridge and EPFL.

If you are interested in a semester or master student project at Biorob, please contact us! We are always interested in hearing from motivated students. A comprehensive list of past student projects can be found here, a list of open projects can be found here. We are also open for suggestions.

 

Copyright

Feel free to use pictures and movies without prior permission, provided they are credited as follows: Biorobotics Laboratory, EPFL. Please contact us by email if you would like additional information or higher resolution videos.

Publications