Self-reconfiguration for adaptive furniture

Jocelyne Lotfi

Content

Goal of the Project Previous work of Masoud Asadpour

Presentation of the algorithm My contribution

Changes made Future Work and Time Table

Goal of the project

Adapt an existing reconfiguration algorithm for the roombots

Improve the efficiency of this algorithm

Work of Masoud Asadpour

Graph representation Signature Distance Metric Full Algorithm

Graph representation

Each node is one robot

Each edge have a label representing how they are attached

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Signature

How to say that two graph are the same ? => Signature feature

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start

Signature : [1 e1 2][2 e2 3][3 e3 2][1 e4 4][4 e5 5][4 e6 6][6 –e7 1][1 –e8 7]

Distance Metric

Next question : how far are we from the goal ? Graph Edit Distance Maximum Commun Sub-Graph, in practice use

of an upper-bound.

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Initial position Final position

Edit Actions

Attach and Detach Imply robot’s servo

moves not taken in consideration

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Full algorithm

begin

end

Compute Sgn(I), Sgn(F)

Signature DB

P-Queue

Sgn(I)=Sgn(F) ?Y Output the

solutionPush I in a priority-queue

I← Pop from the P-Queue

I’← Apply action a to I

Compute Sgn(I’)

Sgn(I’) already exists?

Save Sgn(I’)

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Push I’ in the P-Queue

Loop for Feasible actions

Manual Revision

queueempty

My contribution

Adapt the algorithm for roombots Change of labeling and adding of move

actions.

What is roombots ?

Move Actions

Overall goal => having furniture Three levels of freedom imply lots of movements Want to get a type of “stuck” form in space

Move Actions Change configuration in space => change

of labelling

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Change in the algorithm

Need of a fixed position representation of the robot

Move action = Detach action followed by Attach action => no change in the underlying theory base on graph edit distance

Same kind of graph, so reusability of signature process

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Now

I have adapted the algorithm for roombots with Move action implemented

Need of test : Number of action between start and end

configuration found compare to minimum Speed

Future Work

Improve efficiency by :Different search approach

Stochastic method

Adaptation of the signature process for highly symmetric modules

Possible bigger structure handling

Time Table

November => tests of the current version + change of search approched

December => adaptation of the signature + big structures handling (if enough time)

January => report + presentation

Questions ?