CMU Quadcopter System Overview

Hardware

• Tarot Ironman 650 Frame
• Sunnysky Brushless Motor x 4
• HobbyKing ESC x 4
• Pixhawk Flight Controller
• RPLidar A2
• 11x47 Propellers x 4
• Odroid XU4
• Teraranger One

Software

• PX4 Flight Stack
• ROS Kinetic
• Ubuntu 16.04
• MAVROS
• Cartographer

System Diagram

Breakdown

Teraranger One

Product Page
Accurate and fast distance sensor, uses IR time of flight to capture distance.

RPLidar A2

Product Page
Cheap and effective LIDAR

Odroid XU4

Product Page Small but powerful Embedded computer

Pixhawk

By far the most popular open source flight controller in the world

Operating Procedure (Positon Control)

1. Power on System by plugging in LIPO
2. Check Odroid power up by status LED (blue light flashing)
3. Disable safety by pressing the red safety button until LED turns from flashing to solid red
4. Open Terminal or Terminal Emulator and SSH into Odroid via following

# NOTE: Both Odroid and client must be on CMU or CMU-SECURE network
ssh odroid@efang_odroid.wv.cc.cmu.edu
# Password if prompted is: odroid

5. Once SSH session started, source workspace

source ros-odroid-cmu.sh
cd sandbox/quadcopter
source devel/setup.bash

6. Repeat steps 3 & 4 for a new terminal window, else use TMUX or screen to open a new window (guide here)
7. In one terminal, start MAVROS and preparatory ROS nodes

roslaunch hallway_navigator cartographer_mavros.launch

8. In the other terminal, start cartographer and associated ROS nodes

roslaunch hallway_navigator cartographer_slam.launch

9. (Optional) On client side computer (laptop), establish ROS network (script modification described below)

source ros-odroid-cmu.sh

10. (Optional) use rviz to view mapping and localization

11. Arm the drone and perform liftoff in MANUAL mode

12. switch to POSITION mode once in desired position

Notes

• Script for establishing client side ROS network is given here, alter ROS_IP as seen fit
• During testing always grab onto the drone in case of unexpected behavior
• Do not connect the Pixhawk via its micro-USB port to a computer while it is also powered by battery
• installing QGroundControl can be helpful as a ground station