Category:Hamster

• 

  HamsterV3

• 

  HamsterV4

• 

  HamsterV5

• 

  Hamster in TEDX

• 

  Hamster TEDx

Hamster system

Robot's components

Each robots have two raspberry pi computers on board - master and slave, and a low level controller.

Master - Has a wifi connection to the hamster network, provides network access to slave. It also connected to the slave computer directly via ethernet cable.

Slave - Second computer, used primarily for slam/localization algorithms, connected to hamster network via master.

Low level controller - Arduino based board responsible for interaction with hardware components.

Operation modes

Hamster robot is capable of running mapping, localization or outdoor localization (using GPS and IMU).

Switching between modes:

In order to change operation mode publish std_msgs/String message to /mapping_command topic, containing on e of the following strings:

• slam
• localization
• outdoor

Example: <syntaxhighlight lang="bash" line='line'> rostopic pub /mapping_command std_msgs/String "data: 'slam'" </syntaxhighlight> <syntaxhighlight lang="bash" line='line'> rostopic pub /mapping_command std_msgs/String "data: 'localization'" </syntaxhighlight>

When switching from mapping to localization mode, the map is saved by the server, and loaded for localization algorithm.

Hamster wireless network

Router

• SSID 2.4Ghz: hamster_net
• SSID 5.0Ghz: hamster_net5
• Password: hamsterHAMSTER
• Network: 10.0.2.0
• Netmask: 255.255.255.0
• Gateway: 10.0.2.138

Hamster

• User = pi
• Password = hamster

Master:

• IP: 10.0.2.n/192.168.1.n

Slave:

• IP: 192.168.n.2

n - stands for agent id, e.g agent1 will have 10.0.2.1/192.168.1.1

Low level controller

Hamster Ardino connection scheme (for V4 and V5)

Description

Arduino based board responsible for interaction with hardware components such as:

• Motors (drive and steering)
• Encoders (mainly used for PID controller)
• IMU
• Battery monitoring
• Cut-off (shuts down the platform when battery goes below certain voltage)

The LLC is connected to master computer via UART (serial)

A built-in switch is also provided for the possibility of loading the code on Ardiuno

Server

Description:

Usually runs ROS master services, it also loads and publishes the map for localization

Note: hamster robot may be configured to use local ROS master to avoid using dedicated server for this purpose

Packages:

1. hamster_server_launch

2. map_server

3. mapping_controller

4. (Optional) mrm_control_panel

Master

Description:

Majority of hardware is connected to the master pc, it also acts as network gateway for slave

Hardware

* WiFi
* Low level controller (via UART)
* LiDar (USB)
* Ethernet (to slave)

Packages