Computational Intelligence - August 2014 - 60

execution, it first sends a regare seven types of messages:
istration message to the regisregistration and deregistration
Face Recognition and
tration module. The registramessages for registering and
Marker Detection Program
tion message contains
deregistering corresponding
information of the agent, and
agents to the system, data
that information is stored in
messages for providing comRGB Image
the agent database. On the
putational results of a correother hand, when the agent
sponding agent to other
terminates, it sends a deregisagents, request and response
Camera
tration message, which conmessages for communication
tains its restoration data. The
among agents to share each
(a)
restoration data stores the last
other's functionality, and resinternal state of the agent, and
toration and deactivation
it is stored in the agent datamessages sent by the agent
Face Recognition Program
Marker Detection Program
base by the registration modmanager to support automatic
ule. The corresponding agent
execution and termination of
receives this data when it is
the related agents. In this
RGB Image
RGB Image
executed again.
paper, the messages are impleThe communication modmented using Java Script
ule shares the data and funcObject Notation (JSON)
Camera (1)
Camera (2)
tions of agents through
which has a smaller data size
inter-messaging among agents.
than XML and is simpler than
(b)
It handles three types of mesbinary encoding [34].
sages: data, request, and reThe following is a list of
sponse messages. A data
the seven kinds of imple- Figure 4 Two example structures for most of the existing robot development platforms: (a) an integrated software component of the two
message sends data from one
mented messages:
image processing algorithms and (b) two separate software compoagent to other agents.When an
i) Registration message from nents each for a corresponding algorithm.
agent sends a data message, the
an agent: The registration
communication module transfers the mesmessage, 'input': specifier for the
message from an agent consists of
sage to proper agents according to the derequested data, e.g. pixel position,
several key-values, such as 'message
scriptions of agents in the agent database.
sensor ID, etc., and 'data type': the
type': the type of the message, 'verMoreover, for safe operation of the robot
type of the requested data.
sion': the protocol version of the
system, data flow could be permitted or
v) Response message from an agent: The
agent for judging the compatibility
blocked by the data flow control module.
response message from an agent
of the corresponding agent with the
The communication module transmits
consists of 'message type': the type
agent manager, 'agent name': the
data messages only when the data flow is
of the message, 'input': specifier for
name of the agent, 'input data': the
permitted. Such permission information is
the requested data, e.g. pixel positype of input data, and 'output data':
stored in the data flow database. When an
tion, sensor ID, etc., 'data type': the
the type and class of output data.
agent needs some data, it sends a request
type of the requested data, and
ii) Deregistration message from an agent:
message to the communication module.
'data': the requested data.
The deregistration message from an
The communication module finds the
vi) Deactivation message from the monitoragent consists of 'message type': the
agent that can generate the data by checking module: The deactivation mestype of the message, 'restoration
ing the descriptions of agents in the agent
sage from monitoring module to an
data': the data specifying agent's last
database and then transmits the request
agent consists of 'message type': the
active state, and 'execution filename':
message to the found agent. Such request
type of the message.
the execution filename of the agent.
information including the request time is
vii) Restoration message to an agent: The
iii) Data message from an agent: The
stored in the communication database.The
restoration message to an agent
data message from an agent consists
agent that has received the request message
consists of 'message type': the type
of 'message type': the type of the
sends back a response message that conof the message and 'restoration
message, 'data type': the type of
tains the requested data to the communidata': the data specifying agent's last
the transmitted data, e.g. behavior,
cation module. Then, the communication
active state.
measurement, etc., and 'data': the
module transmits the requested data to
In the agent manager, the registration
data value.
the requesting agent according to the remodule manages the agent database to
iv) Request message to an agent: The
quest information in the communication
store the information about all the
request message to an agent consists
database and then removes the request
agents. When an agent is activated for
of 'message type': the type of the

IEEE ComputatIonal IntEllIgEnCE magazInE | august 2014

Table of Contents for the Digital Edition of Computational Intelligence - August 2014