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Rudder position
#1
Great project!

One question though: how do you get actual rudder position? I don't see any sensor or encoder that would return actual value... 

Thanks!
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#2
The error in integrating the relative rudder movement is a very small part of the total error in maintaining course. I have good results without any rudder feedback.

I have plans to incorporate optional rudder feedback in the future to possibly improve self-learning, but again, it is not really needed.
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#3
I see, thanks.
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#4
Is there some awareness of when the rudder is at its limits? Perhaps feedback from the motor controller?
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#5
The current in amps is measured, and the controller cuts power above a threshold. This appears to work fine for the drive units I have, but if there is enough momentum, and not enough padding, it might not be sufficient.

The controller also has (optional) pins for momentary switches (or reed switches) These prevent additional travel in each direction.

rudder feedback can eventually also prevent end of travel but is not fully implemented yet.
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#6
(12-30-2017, 12:13 PM)seandepagnier Wrote: The current in amps is measured, and the controller cuts power above a threshold.  This appears to work fine for the drive units I have, but if there is enough momentum, and not enough padding, it might not be sufficient.

The controller also has (optional) pins for momentary switches (or reed switches)   These prevent additional travel in each direction.

rudder feedback can eventually also prevent end of travel but is not fully implemented yet.
I truly love the amps power cut. My current st7000 does not have it. My wheel was blocked and next the ram broke out of the quadrant. Easy fix. But cutting power in 1/10th of a second could have saved me the trouble!

Will still use the rudder reference that is there for the st7000.
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#7
The rudder feedback is fully implemented now. The over current only triggers if no rudder feedback or end stop switches or they don't work. For tiller pilots I use this, and it seems ok for hydraulic but still safer and less stress to not rely on current detection for powerful drives.
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#8
(10-23-2018, 03:02 PM)seandepagnier Wrote: The rudder feedback is fully implemented now.  The over current only triggers if no rudder feedback or end stop switches or they don't work.   For tiller pilots I use this, and it seems ok for hydraulic but still safer and less stress to not rely on current detection for powerful drives.

I am right in understanding that current triggers will not work if rudder position is implemented? In other words that a blocked wheel will not trigger over current if I have rudder position?
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#9
The overcurrent protection is always working if available. This will trigger if the wheel is stuck. One issue is, if it does get stopped, then it will allow a higher current in the opposite direction to try to "unstuck" itself but this is usually ok even if the wheel is stuck.

Depending on the controller it may or may not have:
1) overcurrent - works for end of travel or blocked wheel
2) end stop switches - switch in either direction prevents further travel
3) rudder feedback - user sets rudder range and movement doesn't go past this


My controllers support all 3, but I do not provide hardware for #2 or #3 (yet) so they must be wired to the controller if they exist. Several other members have implemented controllers without #1 which I don't recommend, but as long as one of the above is implemented, there is a way to prevent stalling. These controllers obviously won't detect a stuck wheel. Any or all of these can be used at the same time, and the logic individually does not change. For example, having end stop switches will work as backup if the rudder feedback fails. If the end of travel switches fail then overcurrent will be triggered.
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#10
Great! Thanks - nice work.
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