Modlab The Modular Robotics Laboratory at the University of Pennsylvania

Modlab
SMORES
The design of this system called SMORES (Self-assembling MOdular Robot for Extreme Shapeshifting) is capable of rearranging its modules in all three classes of reconfiguration; lattice style, chain style and mobile reconfiguration. Modules are independently mobile and are capable of self-assembly from a collection of disconnected modules.

Introduction

Self-assembling and self-reconfiguring modular robot systems may one day be capable of achieving varied, complex tasks. Having the abilities of coordinated self-assembly and self-reconfiguration could allow a robotic system to adapt to different or  hanging environments on-the-fly. These robotic systems have the potential to exploit self-healing abilities with a reserve supply of low cost robot modules for increased system robustness. They are particularly well suited to situations in which they must adapt to tasks not known a priori, such as search and rescue applications in unstructured environments, planetary exploration and deep space exploration. Two prototype SMORES modules have been developed at the time of this post.

 

Hardware

Module Overall Design

SMORES showing 4 DoF per module

 

Specification Value
Wheel Speed (No Load) 23 RPM (9V)
Pan Speed (No Load) 23 RPM (9V)
Tilt Speed (No Load) 23 RPM (9V)
Maximum Land Speed 1.1 Body Length/s
Wheel Torque (DoF 1 and 2) 1.2 Nm
Pan Torque (DoF 3) 1.4 Nm
Tilt Torque  (DoF 4) 2.3 Nm
Static Module Power Dissipation 1.7 W (9V)
Overall Dimensions 100 x 100 x 90 mm
Module Weight 0.52 kg
Modules cantilevered under gravity (DoF strength) 2 Modules
Cost $300 USD

 

Docking Connector Design

 

 Internals of a Module showing docking key actuation

 Docking Connector Strength

Specification Value
Number of Ports 3 Active, 1 Passive
Average current draw 0.85 A (9V)
Holding force in tension 60 N
Max. holding force in shear 3.6 kN
Max. torsional load 11 Nm
Modules cantilevered under gravity (connector strength) 3 Modules
Min. time to undock 0.8 seconds
Max. time to undock (worst case docking key position) 2.3 seconds

 

Movies

SMORES – Highlights (self-assembly, self-reconfiguration, mobile modules, 4DoF, manual control, tele-operation)

Internal Gearing

Dock/Undock

Docking mechanism internals

Pan and Tilt Camera mount

Failed docking recovery

Publications
[SMORES.pdf]

  • [DOI] J. Davey, N. Kwok, and M. Yim, “Emulating self-reconfigurable robots – design of the smores system,” in Intelligent robots and systems (iros), 2012 ieee/rsj international conference on, Vilamoura, Algarve, Portugal, 2012, pp. 4464-4469.
    [Bibtex]
    @INPROCEEDINGS{JD:NK:MY:12,
    author={Davey, J. and Ngai Kwok and Yim, M.},
    booktitle={Intelligent Robots and Systems (IROS), 2012 IEEE/RSJ International Conference on},
    title={Emulating self-reconfigurable robots - design of the SMORES system},
    year={2012},
    month={October 7-12},
    address={Vilamoura, Algarve, Portugal},
    pages={4464-4469},
    keywords={robots;self-adjusting systems;SMORES system;chain style reconfiguration;lattice style reconfiguration;mobile reconfiguration;selfassembling modular robot for extreme shape-shifting;selfreconfigurable robots;universal modular robot;Connectors;Gears;Lattices;Mobile communication;Robot kinematics;Wheels},
    doi={10.1109/IROS.2012.6385845},
    ISSN={2153-0858},
    url={modlabupenn.org/wp-content/uploads/SMORES.pdf},}

 

2 Responses to SMORES

  1. Weiwei Tao says:

    Dear Modlab,

    It’s nice to know you. I am a senior student at University of Science and Technology of China.

    I have just read your paper about SMORES system. Your research is really amazing. It is the first time for me to learn about modular robot and I am totally fascinated by your design, especially the four-DoF module and docking key system. It is intelligent to achieve the control of three connecters simultaneously actuated by only one motor.

    May your further research can go on successfully. Best Wishes to you!

    Yours sincerely,
    Weiwei Tao

  2. jaydavey says:

    Thank you for your kind words Weiwei Tao. Let us know if you would like to know more about SMORES or any of our other modular robotics research efforts. Good luck to you too in your future endeavors.

    Cheers,

    Jay Davey