MailBot

EE4-60: Human Centered Robotics [Imperial College London]. 2018-2019.

MailBot is an internal mail delivery service for the Electrical and Electronic Engineering department at Imperial College London. Sending a parcel to the office of your academic tutor has never been easier.

Table of Contents

1. ROS Architecture Description
2. Setup
   1. Interface
   2. ROS
      1. Dependencies
      2. Usage
      3. Quality of Life Scripts
   3. Hardware

ROS architecture description

• Bluetooth Node - movement/catkin_ws/src/mailbot/scripts/BTApp.py: Connects to tablet via bluetooth. Receives string of locations to visit and passes these to TSP solver on /deliveryLocations. Listens for /atLocation and notifies tablet. When a delivery is complete it posts to /deliveryComplete, to notify the queue. Sends serial commands to the Arduino to unlock locker latches.
• Arduino Script - hardware/Arduino-latch-code/latch.ino: Loaded to the Arduino. When it receives a value via serial it opens the corresponding locker
• TSP Solver - movement/catkin_ws/src/mailbot/scripts/tspSolver.py: Takes a string containing a list of locations e.g. 507 508 510 from topic /deliveryLocations and posts a solved route based on an input cost matrix 'Weights.csv' to /solvedPaths. Other solvers tested are included in EarlyTspTesting.
• Goal Queue - movement/catkin_ws/src/mailbot/scripts/locationQueueMoveBase.py: Takes a list of locations from /solvedPaths and passes the first location as a goal (MoveBaseGoal) to the navigation stack as an action. When it receives a result it will post that location to /atLocation. It then waits for a /deliveryComplete post.
• Navigation Stack: Consists of many packages, transforms, config files. Takes a map, odom data, kinect sensor info etc. and a goal from Goal Queue and outputs twist messages to Rosaria to control the robot.
• RosAria: Framework used to interact with the P3AT to provide it with twist messages and such.

Setup

Interface - MailBot/interface

Android application created for the Lenovo Tab 2 A-10 70F (Android Version:6), on Android Studio (3.1).

The Android Studio Project folder is: MailBot/interface/mailbot. This can be used to export an .apk for installation.

MailBot/interface/Bluetooth: cotains some old bluetooth testing scripts.

ROS - MailBot/movement

The MailBot/movement/ folder contains the catkin workspace catkin_ws. The system used was Ubuntu 16.04 running ROS1 (Kinetic).

Dependencies

1. apt-get related installs (detailed in : AnyInstalls.odt):
   1. sudo apt-get install ros-kinetic-rviz-plugin-tutorials [Teleop plugin for rviz]
   2. sudo apt-get install ros-kinetic-p2os-urdf [Robot model]
   3. sudo apt-get install ros-kinetic-rtabmap-ros [RTAB-MAP]
2. Other 'git clone'installed ROS packages (incl. commit hash) used:
   1. depthimage_to_laserscan [git clone -b indigo-devel --single-branch https://github.com/ros-perception/depthimage_to_laserscan.git] [git checkout f135fbd5f60dc7b]
   2. iai_kinect2 [git clone -b master --single-branch https://github.com/code-iai/iai_kinect2.git] [git checkout 0e2c5f63134a076606bb7996] NOTE: Not required for current version, this is the Kinect 2 specific driver
   3. openni_camera [git clone -b indigo-devel --single-branch https://github.com/ros-drivers/openni_camera.git] [git checkout e898a]
   4. pointcloud_to_laserscan [git clone -b indigo-devel --single-branch https://github.com/ros-perception/pointcloud_to_laserscan.git] [git checkout ead0804]
   5. rgbd_launch [git clone -b indigo-devel --single-branch https://github.com/ros-drivers/rgbd_launch.git] [git checkout 2123238]
   6. rosaria [git clone -b master --single-branch https://github.com/amor-ros-pkg/rosaria.git] [git checkout aa8d5f7]
   7. rosaria_client [git clone -b master --single-branch https://github.com/pengtang/rosaria_client.git] [git checkout 31bf5c0]
   8. timed_roslaunch [git clone -b master --single-branch https://github.com/MoriKen254/timed_roslaunch.git] [git checkout 5283d6f]
3. install_iai_kinect2.sh is for XBOX Kinect 2 required dependencies, this is no longer relevant as the XBOX Kinect 1 is now used.

How to Use:

1. All scripts located in the catkin_ws/src/mailbot/scripts/ folder were set to executable using: sudo chmod +x <script_name>.py
2. rtabmap_mailbot.launch should be run beforehand to generate a map using the Kinect camera (and odometry provided by RosAria).
3. The mailboot.launch file starts up the major components of the system:
   1. boot.launch : Initialises: RosAria (driver for P3-AT) at specific USB port, includes the URDF model for the P3-AT. Establishes a static transform for the location of the sonar sensors.
   2. kinectBoot.launch: Initialises the Kinect 1. Additionally, the bottom of this file intialiases a static transform for the location of the camera.
   3. nav2.launch: Initialises RTAB-Map and sensor related transforms
      • The .db specified in arg database_path is generated beforehand using rtabmap_mailbot.launch
   4. move_base.launch: Initialises AMCL and
   5. btApp.launch: Initialises the ROS side of bluetooth communications
   6. tspSolver: Receives delivery locations by bluetooth and figures out the best path based on weights.csv.
      • NOTE: The location of weights.csv should be changed in the tspSolver script, variable name: csvPath
      • weights.csv: A lower-left triangular matrix that specifies the 'cost' of going to a given location. Each row/column would correspond to a defined room. e.g. (0,0) = ( start room, end room -1 ) time to go from Room 0 to Room 1
      • Uses https://github.com/dmishin/tsp-solver
   7. locationQueueMoveBase: Associates delivery locations to co-ordinates that are sent to the ROS Navigation Stack. Ensures goals are sent at the appropriate time by communicating with the interface.

Quality of Life Scripts:

1. teleop.launch - keyboard based teleoperation.

Incomplete or Deprecated Scripts:

1. rplidar.launch, laserscan_config.launch & view_rplidar.launch: initialises LIDAR and filters out certain laser data.
2. gazeboMail.launch: Spawns Gazebo model of P3-AT
3. rtabMap-fakeOdom.launch: Uses visual odometry for RTAB-Map

Hardware related - MailBot/hardware

Bill of Materials: MailBot/hardware/BoM.pdf

Latches Arduino code: MailBot/hardware/Arduino-latch-code/

Latches Schematic: MailBot/hardware/Latch_Setup.png

Laser Cutter Design Files: MailBot/hardware/Locker Laser Cutting Design files