Networking Gear Splurge...

A project log for "Tenacity": Yet-Another-Sawppy-Project

Inspired by Roger and others, I'm making a SAWPPY-Alike rover, adding my own tweaks and mods.

steveSteve 02/13/2022 at 11:550 Comments

I've been eyeing the networking products for months but avoiding clicking on "Buy" because they were pricey but also came with a hefty shipping costs from the UK that made the on-my-desk costs almost 2X what the devices themselves costs. Which, I get and which is the world we live in now. So I've been looking and waiting and dreaming and waiting and continuing to struggle w/ USB and udev .

The good news is that there's a cheaper shipping option now and flush with a little extra Xmas cash, I did mash the "Checkout" button and this showed up on my desk at CircuitLaunch within a few days of ordering it last month.

In case it hasn't sunk it yet, it's a tiny,tiny little gigabit network switch designed specifically for robots and drones. I'll let you go get all the specs off the Botblox site, but just look at it sitting on top of the TP-Link 5-port 100Mbit switch it's replacing. So tiny! So glowy! Botblox have been able to shrink a switch down to this size by engineering out most of the transformer/power management electronics that are in a typical switch. As a result, it's really meant to be installed in an isolated environment, like, say, a robot that needs its own internal LAN that doesn't really connect to the outside world.

So far it streams RGB & depth data off the OAK-D camera at 30FPS just fine and brings the entire networking stack up to 1 Gbit everywhere AND a 1A power savings. The electronics/compute bus is down to 2-2.5A draw now and that's low enough to dump the current honking 10A step-down that I got as a hand-me-down when I was first putting Tenacity together 3 years ago. 

Slowly, bit-by-bit, early parts are getting swapped out for smaller, lighter, more capable, less power-hungry ones. The L298N motor controllers are gone, replaced with a VNH5019 from another robot a few months back. The tangle of Arduino Nanos, USB cables and udev rules are being replaced with Ethernet-capable Teensy boards( One of which, TBH, probably could run the entire rover, minus the cameras, if I felt like rewriting the entire control stack in custom C vs ROS) .

The new shininess, tucked away under the top deck. It needs a proper 3D-printed case, but this will have to do for now.