Fabricating Internal Structures - LoCO-AUV/loco_config GitHub Wiki

The list of internal structure parts needed for LoCO is below. Using the tips from the general fabrication instructions page, fabricate these parts with a 3D printer and laser cutter, then have them prepared for assembly into the full robot (instructions for which follow later).

3D Printed Parts

1 x Reed Switch Holder

CAD - Reed Switch Holder
STL - Reed Switch Holder

Holds the reed switch up against the side of the left tube. Attaches to the MDF base with 8-32 x 3/4" machine screws and nylon locking nuts.

1 x Magnet Holder Top

CAD - Magnet Holder Top
STL - Magnet Holder Top

The top piece of the magnet holder. Glued into the Magnet Holder Bottom piece.

1 x Magnet Holder Bottom

CAD - Magnet Holder Bottom
STL - Magnet Holder Bottom

The bottom piece of the magnet holder. Holds a 11x11x11mm neodymium cube magnet. Glued into the Magnet Holder Top piece.

1 x Raspberry Pi Pixhawk Holder

CAD - Pixhawk Holder
STL - Pixhawk Holder

Attaches to the Raspberry Pi with M2 self-tapping screw. The Pixhawk is mounted on top with hook and loop tape.

1 x Orbitty Jetson Mount

CAD - JetsonMount
STL - JetsonMount

Holds the Orbitty and Jetson boards. Attaches to the MDF base with M2 self-tapping screws.

8 x Battery Corner

CAD - BatteryHolders
STL - BatteryHolders

4 of these pieces hold 2 batteries in place. Attaches to the MDF base with 8-32 x 3/4" machine screws and nylon locking nuts.

1 x OLED Mount

CAD - OLED Mount
STL - OLED Mount

Holds the OLED display in place above the cameras. Attaches to the base with M2 self-tapping screws.

1 x Plug Holder

CAD - Plug Holder
STL - Plug Holder

Connects the MDF base to the tube via the back plugs. Attaches to the MDF base via an 8-32 bolt, pressure fits onto the waterproofing plugs.

Laser Cut Parts

CAD Parts - MDFBaseLeft , MDFBaseRight

CAD Drawings - MDFBaseLeft , MDFBaseRight

Drawing PDFs - MDFBaseLeft , MDFBaseRight

Alternative Assembly Using 3D Printed Electronics Structure

The above works for those who have access to laser cutting or jigsaw equipment that can cut MDF material. However, our current recommended approach uses entirely 3D printed structures. This has the benefit of eliminating equipment requirements. However, the downside is this approach requires more hardware such as screws, spacers, and heatset inserts.

These are described below, along with corresponding hardware requirements

Hardware requirements

A labeled view is shown below. There are four primary sections that need to be printed (Jetson, Battery, Teensy/HREye fore sections, and the HREye integrated camera mount.) These sections bolt together and form a concentric set of rings that protect the internal electronics from damage during sliding the electronics in and out of the tubes.

2 x Jetson/Raspberry Pi Sections

CAD - Jetson Section
STL - Jetson Section

This part houses the Jetson and Raspberry Pi in both the left and right tubes. It interfaces with the Blue Robotics 4" flange (old style).

Requirements for assembly:

  • x 4 M3 x 16 mm screws

2 x Battery Sections

CAD - Battery Section
STL - Battery Section

This part houses the batteries in both the left and right tubes. It interfaces with the Jetson Section and the HREye Teensy Section.

Requirements for assembly:

  • x 3 M3 x 16 mm screws
  • x 4 M3 heatset inserts

2 x HREye Teensy Sections

CAD - Teensy Fore Section
STL - Teensy Fore Section

This part contains the HREye Teensy and Trinkets for controlling the HREye systems. It is the front section that interfaces with the middle Battery Sections.

Requirements for assembly:

  • x 4 M3 x 12 mm screws
  • x 4 M3 heatset inserts

2 x HREye Mounts

CAD - HREye Mounts
STL - HREye Mounts

This part mounts the HREyes. It mounts to the Teensy HREye fore section.

Requirements for assembly:

  • x 4 M3 heatset inserts