Servers by jDrones

What am I missing with my first Autonomous Boat project?


(Conrad) #1

I am familiar with bathymetric mapping using my Humminbird fishfinder on my 14’ aluminum boat, however I am looking at automating it. I have played with Mission Planner to get familiar with the software before obtaining any hardware. I am in the process of purchasing all the hardware and just wanted some feedback.

This is what I am looking at for the electronics side is:

Pixhawk PX4
https://www.aliexpress.com/item/PX4-PIX-2-4-8-32-Bit-Flight-Controller-433-915-Telemetry-Neo-M8N-GPS-Minim/32759523206.html?spm=a2g0s.13010208.99999999.273.LOmvL2

FrSky Transmitter
https://www.aliexpress.com/item/FrSky-ACCST-Taranis-Q-X7-QX7-2-4GHz-16CH-Transmitter-With-O-Receiver-Mode-2/32792098194.html?spm=a2g0s.13010208.99999999.270.LOmvL2

FrSky Receiver
https://www.aliexpress.com/item/Frsky-X8R-2-4GHz-16Channel-Telemetry-S-Bus-Output-Smart-Port-Receiver/32387368267.html?spm=a2g0s.13010208.99999999.263.LOmvL2

The boat is a 5’ PT109 Patrol Boat with Zenoah G260PUM 25cc engine and twin drive props. It’s used and needs to be completed, which won’t be a problem. But it’s a fairly large working platform to work with and the price is right…

  1. I was just wondering what would be the range this boat would be limited to? Can you program in Mission Planner the route and load it into the PixHawk and let it go?
  2. Does it need to be within radio range, I would assume not? What is the range of the radio?
  3. Which frequency telemetry would provide the best range? What would the typical range be?
  4. Is there any way to increase the range?
  5. For the price range is there any other hardware better than the Pixhawk PX4 that will work with Mission Planner?

(gmorph) #2

When you say range do you mean radio range as apposed to fuel range? Your FrSky is normally ok for 1-2km depending on conditions. Yes you can program in the mission and let it go - it will do everything autonomously. You should also have a telemetry radio. If you buy the 1W RFD900 radios they are good for 40km line of site. Generally speaking the lower the frequency the longer the range but the lower the data rate.

The latest hardware is the Pixhawk 2.1 Cube.
http://ardupilot.org/rover/docs/common-pixhawk2-overview.html

Thanks, Grant.


(Conrad) #3

Thanks for the info Grant! I have since ordered all those items along with a few other things as well. I have all winter to get everything laid out prior to testing in the spring so I presume I will be ordering a few other items as well.

Good to know once it’s programmed with Mission Planner it can go until it’s completed the mission, run out of fuel, batteries or anything else catastrophic. Haha.

Thanks for the info on the cube, I have seen so much documentation for the PX4 it should help flatten my learning curve a bit. Once I get used to it and find limitations then I think I’ll be ready to upgrade.

On the boat I plan on running a Humminbird fishfinder, 798CI HD SI (one that I already have) and will be recording the data to the SD card within the unit, however I want redundancy in that data so am now adding a Raspberry PI3 to load mission planner onto as well as record the NMEA data from the fish finder. The Pi doesn’t have enough processing power to run Reefmaster, however I was thinking of an XBee-Pro 900 XSC S3B Wire (https://www.sparkfun.com/products/11634) to possibly SSH (would that be possible?) into the Pi to edit or monitor the Mission Planner progress. Also to relay the NMEA fish finder data to my laptop on the shore which would be running Reefmaster. So I could see in real time the map being generated from shore, but if there is a break in communication it’ll still be recording to the fish finder as well as the PI onboard.

Would the XBee-Pro 900 XSC S3B with a Pi offer more control than the RFD900 radio?


(gmorph) #4

You should read this page if you haven’t already
http://ardupilot.org/dev/docs/raspberry-pi-via-mavlink.html

Not sure why you are running MissionPlanner on the Pi? Can you explain the point of that i.e. what your trying to achieve? Most people run Linux on the companion computer and MAVProxy. Ardupilot has prepared images you can find on the link above to do just that.

I know nothing about the XBee-Pro 900 XSC S3B - your own your own there - sorry. We do have an XBee page here http://ardupilot.org/copter/docs/common-telemetry-xbee.html but as I recall the XBee firmware was fairly crappy and not the preferred option but my information is very old.

For long range comms to the raspberry pi a mobile broadband dongle can work well assuming you have coverage. Alternatively products like the Ubiquity Rocket M5 but now we are going up in price.

Thanks, Grant.


(Conrad) #5

Yes that’s exactly what sparked the interest of having a Pi onboard. I read somewhere that you could load mission planner on onto a PI, and I thought it would be neat to have all the software on the actual boat itself. That way I could SSH in with any laptop and the mission planner software wouldn’t have to be on the actual laptop itself. However I should only be running one laptop and it should have Mission Planner on it, so MavProxy would be totally fine.

The XBee’s seem to be fairly cheap for the range you can get, but having a low data rate is okay for what I am needing. The main purpose for the Raspberry PI is to get NMEA data from the fishfinder and send it back to the laptop on the shore. That way I can see the map being built in real time in Reefmaster…or so that’s my plan. The RPI can also record the data as well as I’ll have the fishfinder recording to it’s own SD card. Not sure which method will be best…but redundancy and seeing the data in real time would be ideal.

So two sets of transmitter/receivers, one for telemetry of the boat and the other for the NMEA data from the fishfinder. Am I over complicating this?