# Revision history [back]

### Which way should I choose to broadcast a topic in ROCON?

Hi, all! I am establishing a multi-robot system with several turtlebots. Every robot is an individual intelligent agent and same with each other. Then I want every robot in this multi-robot system to share their position. That is every robot has to broadcast its own position to other robots. I think it is easy to achieve this by using the pacakge rocon_mulitmaster

Since every robot in our multi-robot system is same to each other, we has implemented a message topic /position_share which contains the information of robot_id and related information about the robot which publishes the topic /position_share. Every robot in this multi-robot system listens to topic /position_share and do subsequent actions.

However, checking the communication mechanism of advertisment in rocon_multimaster, I am confused on how to broadcast this topic message. Because for the same channel(also topic) /position_share. Every robot (move_base node) has a publisher and subscriber on it. So there is two ways to do this.

 default_advertisements:
- name: /position_share
node: move_base
type: publisher
-name: /position_share
node: move_base
type: subscriber


Which way should I choose to broadcast this topic /position_share?

Obviously, for a receiver, it also has two ways:

  default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: publisher

default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: subscriber


Of course, here I think I should add many gateways in which each of them represent a robot.

Here I am also confused about the type. What should I choose between "subscriber“ and "publisher"? Looking forward to helpful advice, thank you!

### Which way should I choose to broadcast a topic in ROCON?

Hi, all! I am establishing a multi-robot system with several turtlebots. Every robot is an individual intelligent agent and same with each other. Then I want every robot in this multi-robot system to share their position. That is every robot has to broadcast its own position to other robots. I think it is easy to achieve this by using the pacakge rocon_mulitmaster

Since every robot in our multi-robot system is same to each other, we has implemented a message topic /position_share which contains the information of robot_id and related information about the robot which publishes the topic /position_share. Every robot in this multi-robot system listens to topic /position_share and do subsequent actions.

However, checking the communication mechanism of advertisment in rocon_multimaster, I am confused on how to broadcast this topic message. Because for the same channel(also topic) /position_share. Every robot (move_base node) has a publisher and subscriber on it. So there is two ways to do this.

 default_advertisements:
- name: /position_share
node: move_base
type: publisher
-name: /position_share
node: move_base
type: subscriber


Which way should I a robot choose to broadcast this its own topic /position_share? As a subscriber and a publisher?

Obviously, for a receiver, it also has two ways:

  default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: publisher

default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: subscriber


Of course, here I think I should add many gateways in which each of them represent a robot.

Here I am also confused about the type. What should I a robot to choose between "subscriber“ and "publisher"? "publisher" to receive the message /position_share from other robots ? Looking forward to helpful advice, thank you!

### Which way should I choose to broadcast a topic in ROCON?

Hi, all! I am establishing a multi-robot system with several turtlebots. Every robot is an individual intelligent agent and same with each other. Then I want every robot in this multi-robot system to share their position. That is every robot has to broadcast its own position to other robots. I think it is easy to achieve this by using the pacakge rocon_mulitmaster

Since every robot in our multi-robot system is same to each other, we has implemented a message topic /position_share which contains the information of robot_id and related information about the robot which publishes the topic /position_share. Every robot in this multi-robot system listens to topic /position_share and do subsequent actions.

However, checking the communication mechanism of advertisment in rocon_multimaster, I am confused on how to broadcast this topic message. Because for the same channel(also topic) /position_share. Every robot (move_base node) has a publisher and subscriber on it. So there is two ways to do this.

 default_advertisements:
- name: /position_share
node: move_base
type: publisher
-name: /position_share
node: move_base
type: subscriber


Which way should a robot choose to broadcast its own topic /position_share? As a subscriber and or a publisher?

Obviously, for a receiver, it also has two ways:

  default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: publisher

default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: subscriber


Of course, here I think I should add many gateways in which each of them represent a robot.

Here I am also confused about the type. What should a robot to choose between "subscriber“ and "publisher" to receive the message /position_share from other robots ? Looking forward to helpful advice, thank you!

### Which way should I choose to broadcast a topic in ROCON?

Hi, all! I am establishing a multi-robot system with several turtlebots. Every robot is an individual intelligent agent and same with each other. Then I want every robot in this multi-robot system to share their position. That is every robot has to broadcast its own position to other robots. I think it is easy to achieve this by using the pacakge rocon_mulitmasterrocon_multimaster

Since every robot in our multi-robot system is same to each other, we has implemented a message topic /position_share which contains the information of robot_id and related information about the robot which publishes the topic /position_share. Every robot in this multi-robot system listens to topic /position_share and do subsequent actions.

However, checking the communication mechanism of advertisment in rocon_multimaster, I am confused on how to broadcast this topic message. Because for the same channel(also topic) /position_share. Every robot (move_base node) has a publisher and subscriber on it. So there is two ways to do this.

 default_advertisements:
- name: /position_share
node: move_base
type: publisher
-name: /position_share
node: move_base
type: subscriber


Which way should a robot choose to broadcast its own topic /position_share? As a subscriber or a publisher?

Obviously, for a receiver, it also has two ways:

  default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: publisher

default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: subscriber


Of course, here I think I should add many gateways in which each of them represent a robot.

Here I am also confused about the type. What should a robot to choose between "subscriber“ and "publisher" to receive the message /position_share from other robots ? Looking forward to helpful advice, thank you!

### Which way should I choose to broadcast a topic in ROCON?

Hi, all! I am establishing a multi-robot system with several turtlebots. Every robot is an individual intelligent agent and same with each other. Then I want every robot in this multi-robot system to share their position. That is every robot has to broadcast its own position to other robots. I think it is easy to achieve this by using the pacakge rocon_multimaster

Since every robot in our multi-robot system is same to each other, we has implemented a message topic /position_share which contains the information of robot_id and related information about the robot which publishes the topic /position_share. Every robot in this multi-robot system listens to topic /position_share and judges which robots the current message is from and do subsequent actions.

However, checking the communication mechanism of advertisment in rocon_multimaster, I am confused on how to broadcast this topic message. Because for the same channel(also topic) /position_share. Every robot (move_base node) has a publisher and subscriber on it. So there is two ways to do this.

 default_advertisements:
- name: /position_share
node: move_base
type: publisher
-name: /position_share
node: move_base
type: subscriber


Which way should a robot choose to broadcast its own topic /position_share? As a subscriber or a publisher?

Obviously, for a receiver, it also has two ways:

  default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: publisher

default_pulls:
- gateway: robot_id
rule：
name:/position_share
node: move_base
type: subscriber


Of course, here I think I should add many gateways in which each of them represent a robot.

Here I am also confused about the type. What should a robot to choose between "subscriber“ and "publisher" to receive the message /position_share from other robots ? Looking forward to helpful advice, thank you!