Quick Start Guide

Setup

There are three distinct computer groups that require attention during setup:

  1. Ground Station (GS): All involved computer units that are on the ground. In most cases, this would be relay.local, mocap.local, and your own personal computer.
  2. Companion Computer (CC): Computer on-board the quad used for direct access to prototype hardware and algorithms. This is usually a Linux machine with direct access to at least one of the Ground Station units.
  3. Flight Module Unit (FC): This runs direct flight control. Given the safety and real-time requirements for control, this is a discrete unit from the companion computer. This is usually a unit from the Pixhawk family of flight controllers running PX4.

Flight

Important

Quadrotors are dangerous and serious injury may occur from incorrect operation. Proceed with extreme caution. It’s better to be on the ground wishing you were the air, than in the air wishing you were on the ground.

  1. Turn on Motive on the mocap machine.
  2. Set rigid body of the quad with the correct orientation. Verify that the x-axis of the quad is aligned with the long axis of the room and all IR reflection spheres are being registered in motive.
  3. Turn on hand-held control (see Remote Controllers).
  4. Check Lipo battery with battery checker.
  5. Plug into quad (PX4 initialization music will play).
  6. ssh into quad.
  7. Start the software by running roslaunch mslquad quad_vrpn.launch and your controller (see Software).
  8. Review safety checklist below.

Safety Checklist

Important

Make sure you complete the following check list before every flight. Most of the checks are automated by the controller on startup, but that is no substitute for good ol human caution

Hardware

  1. Mechanical

    1. All 4 rotors are tightly secured (more than hand tight)
    2. Battery is secured

  2. Electrical

    1. The FCU serial connection is secured between the px4 and CC
    2. Battery voltage is over the nominal 11.5v (DO NOT start a flight with less than this voltage)
    3. Keep a battery checker handy

Software

  1. Motive

    1. z is up
    2. quad frame is aligned with room (room’s long-axis is quad x-axis)

  2. ROS Topics

    1. local_position/pose matches vision_pose/pose
    2. state has connected=True

  3. PX4 Arms and Kills

    1. Arm the quad by pinching the sticks down and inwards. DO NOT push up throttle stick after arm as this will cause the craft to take off.
    2. Gently push the throttle stick up until the motors start spinning. check that the propeller rotation is in the correct direction.
    3. Disarm the quad by pinching the sticks down and inwards.
    4. Arm the quad again but this time, use the kill switch to disarm. The motors should cut instantaneously.