turtlebot_ws

Semester long project to create a dispenser to dispense a can drink onto a turtlebot, which will autonomously navigate to a set location.

Tutorial

• see alias for full command

• Make sure laptop and pi both connected to same network(hotspot)

• Open 1st Terminal: sshrp -> rosbu after the above is done => To start ros on pi

• Open 2nd Terminal: rslam => take in lidar data and create a map on rviz

• Open 3rd Terminal: map2base => publishes the coordinates of the robot in the map. Map's origin is where rslam is called

• Open 4th Terminal: setwp => main script for autonavigation

• Open 5th Terminal: python3 httpServer.py => starts http server, awaits input from keypad connected to the ESP32

• Open 6th Terminal: sshrp -> switch => publishes the state of the microswitch, whether there is a "can" or not

Aliases

alias rslam='ros2 launch turtlebot3_cartographer cartographer.launch.py'

alias setwp='autonav && python3 setwp_map2base.py'

alias map2base="autonav && python3 map2base.py"

HTTP server

• Make sure laptop, esp32 and pi both connected to same network(hotspot)

• 192.168.109.32:8000 confirm IP address

• to test server connection: local terminal: curl -X POST http://localhost:8000 -d 2 (http not https)

Controls

• w/a/x/d/s - forward/left/backward/right/stop (left and right turns indefinitely, use +/- integers to turn by specific values)

• p - setting current coordinate as waypoint. Input table number to know which table this waypoint will lead to. See more at Setting waypoints

• negative integer - turn right/CW by (-1 to -180deg)

• postive integer - turn left/ACW by (1 to 180deg)

Setting waypoints

• BUG: Expected value: Line 1 Col 1 - Make sure that the .json file has minimum {} in it

Steps:

alias: setwp

1. cw to enter root workspace. ros2 run auto_nav setWaypoints

2. Walk to waypoint

3. Press p. Select table number

Navigation

Getting data from /odom topic

   geometry_msgs.msg.Pose(position=geometry_msgs.msg.Point(x=-0.6580884139688824, y=-0.10369131549389796, z=0.0), orientation=geometry_msgs.msg.Quaternion(x=0.0, y=0.0, z=-0.7199514315963468, w=0.6940244492396294))

Original O(Z): 0 and O(W): 1

Turning anti-clockwise: Orientation (Z) increase, Orientation (W) decrease

Turning clockwise: Orientation (Z) decrease, Orientation (W) increase

Map

Saving map

Open rviz when robot is in either (a)gazebo or (b)physical environment and let the robot roam to explore the map

To save the map into the path defined

```ros2 run nav2_map_server map_saver_cli -f ~/colcon_ws/install/map_loader/share/map_loader/launch/<map>```

Loading saved map

Configuration file for map can be found in src/map_loader/launch/load_map.launch.py

terminal 1: grslam

terminal 2: ros2 launch src/map_loader/launch/load_map.launch.py

Troubleshooting

• No map received - restart rslam and rosbu, make sure that you rosbu first then rslam
• Connection Refused - check same hotspot(NOT the nus), restart hotspot
• RSLAM not working well - Re-rosbu

/opt/ros/foxy/share/turtlebot3_cartographer/config : set use_odom to False