Hello,
I’m new to this forum and hope to get some expert advice. I’ve built a RC trolling motor integrating Mini pix flight controller via ardupilot. I want to use loiter mode to anchor my kayak. And use auto-pilot to way points for trolling for fish. I’ve completed the build but am failing to get the autopilot to use way points and the loiter moves more than I was expecting. I’m using an external GPS and compass. Ive turned off the internal compass in the flight controller. Calibrated. And still same issues. When I try to go to a waypoint my kayak just goes in circles around the area I initiate the auto pilot. Does any one have experience in building a GPS guided arduboat than can tell me what I’m doing wrong or if what I’m doing is even possible to get correct? Or am I wasting my time?
Hi @ArduKayakGuy -
Very cool project! I’ve dreamed of building something like this with a servo and T500 for years. Are you running ArduRover? Can you share your autopilot parameters, or a log file of some kind? You may need to configure your frame to be vectored thrust.
Hi Tony,
Thanks for inquiring. Im running the steering with a 60kg high powered servo. Im am running ardu rover using boat frame. Im getting gps locks within a minute and locks to about 13 to 16 satellites on average. I can see my heading and position in qgroundcontrol app when I’m on the water. But GPS doesn’t seem to be able to tell it where to go. I think I experience toilet bowling. But my external GPS is as far as cable will allow and about 6 to 8 inches away from any wires or electronics. Im stuck and thinking this is as good as it gets 
. Not sure what kind of logs I can provide for trouble shooting as I’m at a loss. Everything working well, except when I need loiter or auto pilot. Can’t tell if there is interference causing GPS or compass issues.
How do I try this vector thrust? How to i configure this in mission planner?
Hi @ArduKayakGuy -
You’d need to edit that parameter to support vectored thrust - it should make a big difference in your vehicles performance, but generally you likely need to tune the vehicle parameters to have it navigate well. This is first done for heading, and then for speed, which combines to then give you navigational performance!
How are you connecting to the system with Mission planner? Via telemetry radios? Do you have an RC receiver / transmitter in the mix as well?
I installed Bluetooth hc-05 module through telemetry port on FC for wireless connection on phone I use qgroundcontrol. On a computer I use mission planner. Yes, running on a rc receiver and transmitter, but needed to get a pwm to sbus converter in order to make this happen. Looks like absolute chaos in the box. Was going for a small form factor. I think I’m going to try to calibrate my compass in an open field tomorrow instead of in my home office full of metal and running computers. Not sure what else to try.
Hi @ArduKayakGuy -
Beyond going through the official tuning process, you may want to make sure high current wires don’t pass close to the flight controller. When they carry power to your trolling motor, the resulting magnetic field could confuse your compass calibration, no matter where you conduct it…
Hi Tony,
Thanks. I think I mentioned I turned off the internal compass (magnometer in the flight control). And using an external compass built into GPS module to avoid high current wires interfering with the FC in the box. This was recommended by RadioLink. I think I will need to run CompassMot to see if my trolling motor wires are causing interference to the external compass. Which is 6 inches away from (basically max distance the stock telemetry cable will allow). Was recommend to keep it 4 to 6 inches from high current motor wires. Should i find interference during CompassMot, how would i block the interference? Or would i splice more wire to telemetry cable to extend the compass even further into the air away from the trolling motor wires? Crossing fingers for next field test… I did successfully calibrate accel and compass in an open field today. In the pic u can see the trolling motor plug into the box. And the antenna stick up on top with a black box gps module with built in pass mounted. Do u think that gps module is far enough away from the cable to avoid interference?
Here another angle of the picture. I’ m measuring 6 -7 inches away from all the wires showing. TS100 is the gps module. Now I have to figure out how to use CompassMot. Ugh…
Hi @ArduKayakGuy -
That separation should be sufficient, sorry for missing that external company detail!
I’d think tuning your system is the next step on the path to a working system. If you put the system in acro mode, does the vehicle hold heading? If not, navigation just won’t work!
Hmm. Im not sure what acro mode does. Never tried. But now I’ll research this since you mentioned this. Thank you so much for your input on my compass orientation. It’s a good start! I’ll reach out with questions once I find out more. Many thanks!
Hi Tony,
Did some reading. Im a bit confused. So in acro mode it allows me to turn and throttle the boat with my stick. Once I release stick to neutral throttle and neutral steering, the kayak should keep the heading I’m facing once I release controls? Can u confirm this? Once I release controls. Is auto pilot suppose to take over and keep the bow of my kayak in the heading I’m facing?
Im new to all of this. I have zero RC, FC, or robotics experience or any technical background at all. So bare with me and my question. This was a project i persued because the autopilot trolling motors on the market are too large for my taste to lug around with kayak. So I wanted to build my own small motor with gps.
And thanks for the resources u linked on tuning and vector thrust. Im diving through these . Extremely helpful!!!
Hi @ArduKayakGuy -
Yes, that’s correct for how Acro mode behaves. If your kayak has the propulsion at the bow, you may need to further modify the autopilot to handle that kind of frame - the Ardupilot forums are a more relevant place to help get that worked out…
