Tuesday, December 1, 2020

Building AMOS 4.0

The past couple of weeks have been spent putting stuff together for the next version of AMOS. It's going to be faster, more powerful, have a longer range, more accurate navigation, and it's going to look amazing. Some potential designs for the hull have been considered:

although nothing definite has been decided yet. Steven Fox, a mechanical engineering technician at Measurand has agreed to help me out with the hull design and construction in his off-hours, so no doubt he will greatly improve upon whatever I would have come up with. I had looked a little bit into 3D-printing or urethane casting for the next version, but these alternatives seemed quite pricey, and I wasn't sure how sturdy the finished product would be. So for now at least, it's looking like it is going to be another foam and fiberglass construction. Just better looking. 😎

Prior to this build I watched a couple of how-to soldering videos on YouTube to refine my technique, and then put together a couple of AMOSRemote boards, one for the handheld unit and one for AMOS:

The boards are fairly simple, so by trying to solder them correctly I was able to actually get them finished much faster (in a few hours) and more cleanly. Only one pad destroyed due to excessive heating. 

Assembling the battery box has been taking a bit longer, but is so far shaping up nicely:

Getting the Raspberry Pi setup will be quite easy. Loading the software is as simple as backing up the existing SD card onto a new one. Getting all of the electrical work done shouldn't take more than a few more days I think. If all the assembly work were organized with readily available parts on shelves that I didn't need to spend hours searching around the house for, I think the electronics for a full AMOS unit could be completed by a single person in a couple of days. 

One of the improvements that will be made on this next build is the addition of survey grade positioning. I picked up a couple of survey antennas and evaluation boards from Taiwan: http://navspark.mybigcommerce.com/px1122r-evb-px1122r-multi-band-quad-gnss-rtk-evaluation-board/. I'm looking forward to their arrival this Friday; it should be interesting to see if it is really possible to get cm-level precision on AMOS by using RTK (Real-time kinematic) with base station and remote devices. 

If anyone happens to be a reader of Ocean News and Technology (https://www.oceannews.com/) be sure to check out their December issue when it is released  (should be any day now!). There may be an article in there that mentions AMOS! 😉


  1. For the RTK using low-cost RTK receivers, it'll all depend on the GNSS antenna. Over water you'll be on a multipath-rich environment, so I think it's a good investment to get a good antenna and a good ground plane. Also, if you have the option, I think it would be a good idea to increase the satellite elevation cut-off to remove water reflected signals. I'm curious to see how it looks like too. Thanks for sharing! :)

  2. Thanks for the tips Marco! I'm very much a newbie with RTK, so any advice in that regard is most welcome! :-)