Home service robot

A practice on Ros path planning and navigation

For Home Service function:

• Using actionlib::SimpleActionClient to send instruct(goal pose) to the robot to move.
• Subscribe topic(odom) to check the the location of robot only on pick_object node.
• However, the goal pose is not the same as the pose from odom topic - always different. As a compromise, I prefer to trust odom's data.
• Register a doneCallback function for action client so that we know when the action finish.
• Regard the robot has reached the goal(pick up zone or drop off zone), if either action client's doneCallback occur or the pose from odom topic close to(buffer) goal's pose.
• Node pick_object maintain the state to control the whole process.
• The key point is to synchronize the action between add_marker and pick_object. I have tried using a topic , but finally choose a service as I do need a response.

So, the complete procedure as below. I indicate all the actions by different states which can be found in the programme:

State BEGIN = 0

0. On node pick_objects: init register subscriber to topic /odom, init a action client for moving the base and a service client to communicate with node add_markers
1. On the node add_markers, init a service server to communicate with pick_objects node, and init a publisher for simulating pickup/dropoff action by show/hide virtual objects in RViz.
2. add_markers set a default place for the virtual object.
3. pick_object set a pickup goal for robot.
4. state => ON_THE_WAY_TO_PICKUP_ZONE

ON_THE_WAY_TO_PICKUP_ZONE

1. pick_object continuously check the pose postion from topic /odom
2. If robot arrives the pick up zone(either from topic odom callback or from action client doneCallback), send a request to add_markers to hide the object
3. Set state => START_PICKING_UP

START_PICKING_UP

1. when add_markers receives the request from pick_objects, it start to hide the object, wait for 5 seconds(like a real picking action), then send the response back to pick_objects node.
2. when pick_object receive the response (hide action done), state => FINISH_PICKING_UP

FINISH_PICKING_UP

1. pick_objects set drop off goal for robot
2. state =>ON_THE_WAY_TO_DROPOFF_ZONE

ON_THE_WAY_TO_DROPOFF_ZONE

1. pick_object continuously checks the pose postion from topic /odom, like ON_THE_WAY_TO_PICKUP_ZONE.1.
2. Like ON_THE_WAY_TO_PICKUP_ZONE.2 when robot arrives the drop off zone, send another request to add_markers to show the object at the drop off place
3. state => START_DROPPING_OFF

START_DROPPING_OFF

1. add_markers show the object, wait for 5 seconds, and send back the response
2. pick_objects receives the response and set state => FINISH_DROPPING_OFF.

FINISH_DROPPING_OFF & END

7. print "job done" and state => END

For localization and navigation, please run pick_object.sh

For mapping test, please run test_slam.sh to manipulate the robot by keyboard.

PS. I use turtlebot for this project.

File struction

├──                                # Official ROS packages  
|  
├── slam_gmapping                  # gmapping_demo.launch file                     
│   ├── gmapping  
│   ├── ...  
├── turtlebot                      # keyboard_teleop.launch file  
│   ├── turtlebot_teleop  
│   ├── ...  
├── turtlebot_interactions         # view_navigation.launch file        
│   ├── turtlebot_rviz_launchers  
│   ├── ...  
├── turtlebot_simulator            # turtlebot_world.launch file   
│   ├── turtlebot_gazebo  
│   ├── ...  
├──                                # My packages and direcotries  
|  
├── map                          # map files  
│   ├── ...  
├── scripts                   # shell scripts files  
│   ├── ...  
├──rvizConfig                      # rviz configuration files  
│   ├── ...  
├──pick_objects                    # pick_objects C++ node  
│   ├── src/pick_objects.cpp  
│   ├── ...  
├──add_markers                     # add_marker C++ node  
│   ├── src/add_markers.cpp  
│   ├── ...  
└──