Trouble with boat thruster build

@redaustin88 

What I believe I’m looking for is a sketch like this… sketch 2 project 2 with the addition of a gyroscope function when called for.

Looking at your sketch I don't understand how the gyro is being used or what type you have?
Do you set the gyro position with the POT?

Doesn't the gyro stay in a fixed position (direction) while the base (boat) turns?

If the gyro is controlling a pot which is being used to control the speed of the motor it would be input to a motor controller that uses the POT value to pulse the full voltage onto the motor.

@will the motor would be in a fixed position mounted on the transom in an orientation that would push the rear of the boat sideways. Yes the motor would need to spin both directions and yes need variable speed to account for different winds and not be jerky in its movement.  

also. The gyro I speak of if is a head hold gyro for rc plane.  

• @robotbuilder I know the pwm is to adjust the motor speed by pulses. The I don’t know part was referring to why I was controlling the pwm with a servo rather than through the arduino. If you would happen to look at a video of a head hold gyro for rc plane my drawing would use the servo that’s controlled by the gyro to flip the pwm in clock wise / ccw  by contacting two different micro switches in place of the normal rocker switch and adjust the pwm pot to adjust speed.  It all seems crude the way it’s in my head and in my drawing.  My help is in could an arduino actually have the gyro on it and control the pwm with output commands instead of the mechanical switch’s and pot. 

The boat already has autopilot I’m preventing yaw from wind as I’m only traveling at a speed of about a 1/2 mph or when I’m stopped the boat acts like a wind sock swing around the pole.  As the main trolling motor that has the gps spot lock is mounted on the front  Also the motor I’m using for the project  in a min Kota endura 55# thrust that would have the top handle and controls removed and be in a fixed position sideways on the rear.  

Thanks again to all that are trying to help with this.  I know my lack of knowledge in this field leaves a hurdle in the road.  And a communication barrier.  

@redaustin88 I have owned a Minn Kota, owned a fishing boat with a remote controlled bow thruster and sailed on a few boats but I still don't fully understand what you are doing. Specifically with the gyro, and pwm. I just don't see the need for either. Unless the MinnKota is a basement variety, it should do everything you need but maybe I am totally confused.

@zander no it’s a very nice minn Kota with spot lock and I pilot link that communicates with my charts and follows the contours and plotted tracks.  But only controls the very front of the boat and at a good speed the boat tracks perfectly behind the motor head.  However while at very low speed and or while on spot lock wind and or current will take the rear of the boat down wind or force the boat to point directly into the current as if it were anchored from only the front. Because really that’s what it is electronic gps anchor.   I’m trying to stop the tail swing with out having to walk to the rear of the boat and manually do it. I’ve spoke with minn Kota at length on this matter and was going to add another gps controlled motor of there’s on the rear but there consensus was that the two motors would fight against each other as both would be trying to hold a spot rather than one holding a spot and the other holding a heading.  And if it was to work on spot lock it wouldn’t do anything while in slow motion.  

@redaustin88 Sorry if I wasn't clear. I was referring to the rear mounted Minn Kota I thought you also had. Under manual control with the remote key fob. You could as you say mount it parallel to the transom and just by going from forward to reverse control the swing without any need to swivel the motor. If that works, then you might be able to figure out what sensor will provide the input and hack the remote to do the output signal. There is a good chance it is one of the radios Bill has video on or BT maybe but I doubt it.

I didn't mention it before because I assumed you had a good reason but the Minn Kota shallow water anchors do what you want but the price is HUGE!

@zander shallow water anchors definitely expensive and I have considered them however most of the time they won’t work for me as I’m usually to deep for them and when I would be shallow enough for them I’d rather not drag them through the stake beds and brush piles.  

@redaustin88 FYI @zander

I probably don't understand the exact problem here, but it seems to me that you're talking about a motor at the back of the boat to maintain position and a motor mounted "edge on" or sideways at the from to keep the boat always pointing in the same direction.

If that's correct, would it be possible to use a compass module at the front instead of the gyro ? I don't know if it would be accurate enough, but I was thinking that you could assign the desired direction for the boat by using the potentiometer to specify a heading and then have the compass module determine the current direction, calculate the current deviation and assign a speed and (+ or -) direction to the front motor to force it to align with the pot setting.

It it worth a cookie or have I still got it all wrong ?

@will Backwards I think. The front motor is GPS guided and has 360 degrees of freedom. The front will stay more or less pegged to one spot. The problem is the back of the boat is free to move anywhere it wants including a full circle around the front.

Obviously big boats have solved the problem with either thrusters or gimbaled fully shrouded drives (I forget the name of them) but he wants to invent his own. 

@will you are on point only that the main trolling motor is on front it pulls the boat and pulls it along in all directions. And the motor on the rear would be fixed sideways and rotate in both directions maintaining a compass heading  based on a command from the gyro or what you’ve called compass module.  I only call it the gyro from my past experience with a head hold gyro on a rc plane.  There are many videos that show there function.  But I do believe you are understanding what I want to do.  

@zander 

Thanks, that helps clear it up a bit for me. So does the back motor play any part in keeping the boat stationary or does the front motor move in all directions to keep the nose stationary ?

if the back motor isn't used, then it could possibly be used for maintaining a compass heading but the calculations would be slightly more complex in order to avoid moving the boat.

@will That sounds about right, but the OP has a good idea, the rear motor should be mounted in a fixed position parallel to the transom. Then with variable speed in either direction it pushes the rear either left or right (port, starboard). They throttle very smoothly and so slow if needed you can watch the prop turn, but also very fast in this case giving 55 lbs of thrust I think. The front motor will automatically keep the nose on station.

Posted by: @redaustin88

@will you are on point only that the main trolling motor is on front it pulls the boat and pulls it along in all directions. And the motor on the rear would be fixed sideways and rotate in both directions maintaining a compass heading  based on a command from the gyro or what you’ve called compass module.  I only call it the gyro from my past experience with a head hold gyro on a rc plane.  There are many videos that show there function.  But I do believe you are understanding what I want to do.  

OK, so as @zander said I had it backwards (not atypical, see my avatar 🙂

As for the compass module, check out the article on using one at ...

https://create.arduino.cc/projecthub/electropeak/make-a-digital-compass-w-gy-511-accelerometer-magnetometer-df9dc1

Which uses the module ...

https://electropeak.com/lsm303dlhc-compass-1

Which is cheaper than a gyro and has the advantage of being already electronic so it can be directly integrated into the controller system.