WorksheetsQuiz 2 TC2343
Total questions: 8
Worksheet time: 18mins
"Simple request/response interaction, as asking a question about a node's state" is example of ___________
ROS Action
ROS Service
ROS Topic
Which of the following is not correct about ROS TOPICS?
Topics implement a publish/subscribe communication mechanism
All messages on the same topic must be of the same data type
Nodes that want to receive messages on a topic can publish to that topic by making a request to roscore
Before nodes start to transmit data over topics, they must first announce, or advertise topic and types.
ros::Subscriber sub = node.subscribe("chatter", 1000, messageCallback);
Which of the following is a CORRECT.
1st parameter is the node name
2nd parameter is the duration time
3rd parameter is the function to handle the message
All the above
Which of the following is INCORRECT?
rqt_graph creates a dynamic graph of what's going on in the system
rosinfo to debug and see what the nodes are doing
roslaunch launching multiple ROS nodes as well as setting parameters
ros::spin()
will not return until the node has been shutdown
calls the callbacks waiting to be called at that point in time
Which of the following is TRUE on Gazebo simulator?
Client: Provides user interaction and visualization of a simulation
Server: Runs the physics loop and generates sensor data
active development at the OSRF (Open Source Robotics Foundation
All the above
World description file in Gazebo ______________
found within the /gazebo directory
contains all the elements in a simulation, including robots, lights, sensors, and static objects
is formatted using YAML and has a .world extension
Component of model definition below are true EXCEPT __________
Collision: A collision element encapsulates a geometry that is used to collision checking
Link: A visual element is used to visualize parts of a link.
Plugins: A shared library created by a 3D party to control a model
Inertial: The inertial element describes the dynamic properties of the link, such as mass and rotational inertia matrix
