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Sean is selling a rudder position hall sensor. The wiki says that a potentiometer is required. I assume that the hall sensor output is a variable voltage that is similar to a potentiometer and that it can be recognized by Pypilot. However, my implementation will require a much smaller sensor than Sean's.
I would like to know what types of hall sensor will work with Pypilot? What are the specs I should look for?
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The motor controller takes a voltage for rudder position. The hall sensor used is mlx90316 however there are a lot of alternatives that would work.
What do you mean you need a smaller sensor? Could you explain a bit better?
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overpowering the oar? I am not sure I understand. If the trim tab is at max deflection that is it right?
If I understand correctly, you have a trim tab on a pendulum oar and the oar drives the main rudder?
Keep in mind doing this will require very little power, but will also have the most lag or delay in reaction to driving the main rudder so will limit the ability to hold a straight course. If you could rotate the oar directly it might help, and/or consider driving the main rudder with a linear sensor in light wind as this doesnt use much power and will give better results, then switch to the windvane in stronger conditions.
anyway.. the rudder feedback sensor I have designed can measure angle to 0.1 degrees, so even if the linkage only moved the sensor by say 5 degrees, it would still give somewhat adequate resolution.
In any case, please post your setup and results as much as you can!
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If you think of a how the Hydrovane works, it's an auxiliary rudder type vane. That's what I have made. The Hydrovane uses gears, mine uses a trim tab, like the old Navik vane. The trim tab is on the aft end of the oar, just like an aircraft aileron. The response of the oar twist is directly proportional to the deflection of the tab. The oar moves immediately. The boat movement, is probably slower. Since it is not a servo-pendulum, it doesn't turn the boat rudder and I expect it to be slower. That's why I want to control tab deflection precisely. If the oar moves and the boat doesn't, the controller could try to over compensate.
I looked at the datasheet for the mlx90316 and it is the IC with many configurations. Your wiki says I need a 3 wire sensor. I didn't see any in there. I was hoping for a standard 3 wire setup that I can just hook up to the controller and done.