mat, thanks so much for your advice and recommendations!
The servo I use I really want to be high quality, I’ve used so many cheap servos over the years in my rc gear but nothing really “solid”. With that in mind would you still recommend the Turnigy TGY58166M?
as for the “mechanism” to actually connect to the shaft of trolling motor how would you recommend going about that?
also you mentioned bearings and a perfect axis alignment, could you explain more?
So after looking endlessly I think I’m going to be using this Steering bracket for trolling motors to attach to a servo…or am what i needing is a servo motor? I’m sorry, I am confused.
I think some stainless clevis rod ends would work if the servo horn is on the same plane as the steering bracket. Or a ball joint link if it’s not. Threaded rod between them.
Depending on what horns are supplied with the servo perhaps you will have to fabricate an adapter on the servo as horns tend to have holes for M3 hardware.
Perfect, I can have them on the same plane I have to make a bracket anyways.
Any idea of how to step down the voltage from my 12v marine deep cycle battery to 4.8 ~ 8.4 (the voltage for the servo y’all recommended from data sheet)?
It does look like they’re holes for m3’s I’ll google about the horn.
Dave, you’ve been invaluable in this process my brother. I googled and have no idea what a stall current is still. Does this essentially mean the servo draws 10A when it moves?
ohh ok so if hypothetically the servo is trying to turn the trolling motor but the motor is stuck against an object and it cant move at that point. Then the servo will draw a max of 10A?
I suspect i should use a fuse, after the dc stepdown? or is that not needed in these servos?
You could use a fuse. It’s difficult to say how much current it will draw under max steering load which I suppose would be at max accleration/speed. You’ll just have to try it out!
hey guys sorry got busy and I see that Dave helped a lot !
A mechanical fuse might be the best to protect the electronics of the servo as well as the gears etc in case of something geting stuck or a shock that will certainly happen at some point anyway.
The mechanical fuse is configured to break upon exertion of a predetermined force, was used on small propellers and avoided exploding the propellers in case of an underwater shock.
This is excellent advice. I have such a device on my Rover. The plastic spur gear fails quickly when the vehicle is stalled under load and they are cheap to replace! It’s driven by a brass pinion which strips it.
Hello,
I have build motor mount for my inflatable canoe. Trolling motor is old MinnKota and it is steered by cheap giant RC servo. MinnKota is set to FWD speed 5 and connected to Traxxas Brushed ESC. Both are connected to Matek F405-WING running Ardurover.
Biggest challenge was to fix servo on trolling motor and keep tilting mechanism working and keep oportunity to quickly pull motor out of water in case of emergency. What I have build is not pretty and look kind of convoluted but it works.
Unfortunately default PIDs are not working for this setup so I have not yet made an autonomous journey.
When I get home I will post more images and information.
If someone wants, I can publish design files. But they are so very specific to my case, components I have used and manufacturing technology I have.
Fun facts:
You can hand RC controller to passenger in front a let him drive. Very useful.
Looking to a laptop while passenger drives and trying to configure Ardurover causes sea sickness
Faces of people watching me driving full size RC boat from shore are priceless.
Facts (not funny but useful):
Trolling motor was not modified at all. In case of failure, I can connect battery directly to motor and get back in normal way (it is awkward on canoe with motor at very end but doable).
Old trolling motors use resistors to slow down. On 1st gear it wastes more energy to heat than goes to the motor (measured). PWM controller is crucial. On highest gear (5) current goes directly to motor. I have kept this throttle switch intact and for normal use I keep it at highest forward gear. ESC is connected externally.
Servo I used is big and strong (33kgf/cm?) but has quite a lot of slop. Trolling motor shaft has slop on its own. I was afraid about this but it has proven not to be a big issue.
Driving at full throttle is about 22A at about 11V (as measured by FC)
That’s looking really good. A beautifully silent boat is so nice.
This vehicle is using vectored thrust so when it comes to tuning, I’d first set the MOT_VEC_ANGLEMAX parameter. the FRAME_CLASS parameter should also be set to boat (2).
The most critical parameter that normally needs tuning is the turn rate controller’s feed forward parameter. This is ATC_STR_RAT_FF and can be tuned in real time as described on the Turn Rate tuning wiki page.