Comparison of Team Robot Localization by Input Difference for Deep Neural Network Model

In a multi-robot system, locating a team robot is an important issue. If robots

can refer to the location of team robots based on information through passive action

recognition without explicit communication, various advantages (e.g. improving security

for military purposes) can be obtained. Specifically, when team robots follow

the same motion rule based on information about adjacent robots, associations can

be found between robot actions. If the association can be analyzed, this can be a clue

to the remote robot. Using these clues, it is possible to infer remote robots which are

outside of the sensor range.

In this paper, a multi-robot system is constructed using a combination of Thymio

II robotic platforms and Raspberry pi controllers. Robots moving in chain-formation

take action using motion rules based on information obtained through passive action

recognition. To find associations between robots, a regression model is created using

Deep Neural Network (DNN) and Long Short-Term Memory (LSTM), one of state-of-art technologies.

The input data of the regression model is divided into historical data, which

are consecutive positions of the robot, and observed data, which is information about the

observed robot. Historical data is sequence data that is analyzed through the LSTM

layer. The accuracy of the regression model designed using DNN can vary depending

on the quantity and quality of the input. In this thesis, three different input situations

are assumed for comparison. First, the amount of observed data is different, second, the

type of observed data is different, and third, the history length is different. Comparative

models are constructed for each case, and prediction accuracy is compared to analyze

the effect of input data on the regression model. This exploration validates that these

methods from deep learning can reduce the communication demands in coordinated

motion of multi-robot systems