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I would start off using what you have and then you can find out what you need. The 1600 is a very small motor, not really suitable for ocean unless it were driving a pendulum oar or trim tab instead of the main rudder.
I would look for wiper motors. Motors that draw 1-2 amps unloaded, and stall at 6-10 amps are about the right side for your boat if they are geared properly.
I am working on using cordless drill motors (already right size motor and gear box) attached to lead screw for 3d printer. This is very inexpensive, but requires an enclosure.
I also just got a 3d printer working on my boat. I am limited to print 1-2 hours a day this time of year until I get more solar panels, but it looks promising for printing the pieces to mount an electric motor with belt drive to a lead screw. I also printed anemometer wind cups yesterday.
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For a tiller autopilot the "at rest position" is mid stroke i.e. 125mm on a 250mm stroke linear actuator. Does the Pypilot software cater for this neutral dead ahead position?
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2018-12-02, 08:44 PM
(This post was last modified: 2018-12-02, 08:46 PM by seandepagnier.)
I read somewhere the pelagic actuator is actually bought from china, and upgraded to make it more corrosion resistant, and brackets added to make it easy to mount. I found similar looking actuators on aliexpress, but none had the speed needed, and were not designed for continuous duty. Where did you find the actuator you mention?
I am hopefully going to release 3d printing files to build your own actuator soon using lead screw (from 3d printer is cheap) electric motor and belt. The $50 figure is achievable, and even using a brushless motor would be possible. Further, it would be possible to scale the design and produce whatever size needed.
The motor controller you linked has been mentioned before. It has virtually no protection built into it. I don't mind you try it, I encourage this, but if it burns the raspberry or the motor, I made my warning a lot of times about this. You might be able to isolate the pwm and direction signals, but there would still be no feedback of motor currents and voltages etc... Please make a thread about your experiments and progress if you try.
I intend to release a controller kit in 1-2 months which will be the latest version of my existing controller so have all of the protection, and other features, but it will require soldering (not surface mount though) and it's going to cost a lot less, but more than $7
Currently rudder feedback is only used to prevent end of travel, and report nmea0183 rudder angle. The error in integrating the rudder error is above the normal errors corrected for, but it would be very interesting to implement a pilot that uses absolute rudder position (nested PID filters) and compare it.
Another nice feature would to have it be able to auto-center, but there is also weather helm to consider.
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(2018-12-02, 03:28 PM)seandepagnier Wrote: .../... The 1600 is a very small motor, not really suitable for ocean unless it were driving a pendulum oar or trim tab instead of the main rudder./...
Hello seandepagnier,
I am using an Aries wind-vane. What would be your recommendation to drive it with PiPylot. Actually I use a shortened dummy air vane with my tiller pylot...
Cordialement
Didier B
Pi4, SSD USB3, OP 3.0 Touch SK 3.2.1 OpenCPN 5.8.4 : Thank you Thank you Thank you