Kayak vectored thruster project

rogerdodger

rogerdodger

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One of the things you learn quickly about using a pedal drive kayak with a rudder is that time and space are required to turn. This is because the rudder needs you to be moving before it can provide any turning force. One way around this is to vector the propulsion, adding an electric trolling motor that turns would be an example, Hobie sells a ProAngler360 in 12' and 14' that use a mirage pedal drive that lets you rotate the fins to change the thrust direction.

Another approach is to add thrust to the rudder, this is what I went with. I added a pair of brushless ROV thrusters to the rudder of my Hobie Outback while still allowing the rudder to retract up under the hull to avoid obstacles.

8J8DDqL.jpg


The build went really smooth, lots of details on parts used are in the video, I ran everything on the outside of the hull, no holes required except in the aluminum rudder from Snipe Air Industries. Using a pair of 12Ahr, 12V LiFePO4 batteries, looks like Pepper and I can go 3mph for probably 3 to 4 hours, plus turn on a dime. (Going to 16V would increase thrust by 50%).

On the water testing starts about 5m05s and I do a '3mph U-turn' about 6m40s, that was real sweet. cheers, roger

PS- any non-human propulsion on any sort of boat in OR requires registration, I would exempt electric propulsion under like 1hp but that's just my opinion, so I went through the process and got mine, not a big deal.

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bass

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That is pretty wild. Any concerns that you are over-stressing the rudder mount? It looks like you swapped the plastic rudder for a metal one, but all the force of the thrust is now on the rudder assembly.
 
rogerdodger

rogerdodger

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hey Bass- I was paying attention to that. If you remove the screw in the center of the round thing on the top, with the rudder down, you can drop down the whole assembly (black plastic pivot and the rudder). the pivot is supported as it turns at several locations (I think it is 3) as it runs up through the hull, so it is fairly robust. The next thing I did was mount the thrusters as high on the rudder as possible, while maintaining full retraction when the rudder kicks up. This reduces the distance from the thruster force to the pivot points, a shorter lever arm basically, so they are doing more pushing and putting less off axis stress on the rotating part. Mounting the thrusters at the bottom of the rudder would have created more stress.

So I liked how things looked and on the water the steering performed just the same as it did before, same force was required to turn the rudder with the thrusters running, it also didn't try to turn by itself, the Outback 'drove' just the same. Except it was like having steering on the rear wheels of a car.
 
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NKlamerus

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Very well done, been looking at similar setups that run on 24v so I could power them with my collection of DeWalt batteries.

Are you running your other electronics off the same batteries? I watched the video but couldn't listen
 
rogerdodger

rogerdodger

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Very well done, been looking at similar setups that run on 24v so I could power them with my collection of DeWalt batteries.

Are you running your other electronics off the same batteries? I watched the video but couldn't listen

no, I'm running my sonar OFF a 6Ahr LiFePO4 battery, 1.6 pounds, inside the hull. my lights (front red/green and rear all white) are both battery powered from Navisafe/Navilight, the standard GoPro mount on them makes it easy to put them up when needed.
 
hobster

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Awesome, looks great. Well thought out as usual!
 

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