Computing System Preparations

Powering Up and Expected Boot Up Sequence

To power on the robot, take the magnetic key and press it against the left (control) tube, at the location of the reed switch (a small black 3D printed part, on the exterior just ahead of the Pi/Pixhawk. Hold it against the tube only briefly, then move it away. Use a sort of slow "stabbing" motion, and do the same to turn it off.

Once the robot has been booted, expect these things to happen:

• The Pixhawk will beep. (Description)
• The ESC's will beep. (Description)
• The Pi power light will come on, as will the power lights on the PDB's.
• The Pi ACT light will blink green.
• The Pixhawk light will first flash yellow, then blue. Once the blue light becomes a solid blue light, you should be ready to go, with motors armed.

During this whole process, if you are connected by Ethernet, you will see connect and disconnect messages several times. This is normal.

Charging

For charging instructions, see here.

READ THE ACTUAL PAGE BEFORE CHARGING, USE THIS CHEAT SHEET FOR LATER

1. Confirm that batteries are all the same cell number (3s), and that each cell is no more than .1V off from the others using a battery beak.
2. Make sure the charger is powered off.
3. Plug the banana cables from Paraboard to charger.
4. Plug the balance cable into the paraboard, then the charger.
5. Power on the charger.
6. Working 1 battery at a time, plug a discharge cable into an XT90 on the Paraboard, then a balance cable to the 3S port next to the XT90. DO NOT REVERSE THIS.
7. Confirm the options are correct. Make sure that 11.1V(3S) is selected, and that the charging amps are no more than 2amps/battery. So (2 amps for 1 battery, 4 amps for 2, and 8 amps for 4).
8. Hold Start, wait for the battery check, then press start again.
9. Charge until 12.6V, no higher. Check voltages with battery beak.

Troubleshooting

• If the pixhawk fails to enter its final state or you have connectivity issues, check that the IPs are set correctly. This should be fixed in the future by setting some static IPs. Make sure that both computer's /etc/hosts files, the laptop's bashrc ROS config, and the pi's /usr/local/bin/pixhawk_start.sh all agree on what subnet things are on.

• If you start up the pi, and after the first little while get no blinking on the ACT light (the green one next to the solid red power light), you might have a corrupted microSD. Reimage your MicroSD and try again (to confirm, check for a rainbow screen when plugging in an HDMI)

• Wireless controllers do not work with the current version of the teleoperation node, pycontroller. Use a wired controller. This has to do with the number of axes sent from the control sticks for different versions of the controller.