So I have a need to have two servos (not an RV) reach run an elevator trim tab and thus it's pretty important that they don't get too far out of sync with each other, so I started working on a little arduino compatible board that uses standard DB25 and DB9 connectors and high quality components with integrated motor drivers so that I can drive each servo and poll the position. I also added a digital pot, so I can report the trim system position back to the EFIS.
This solution should be more reliable than a relay deck because the motor drivers are designed to handle inductive loads and not fry contacts, and because it's completely solid state.
I decided to go ahead and design the board for more generic use, and have the following:
2 motor drivers
2 channel digital pot
6 analog inputs or digital inputs/outputs
6 digital inputs/outputs
This offers the builder the ability, with a little code, to do cool things, like hook up a rotary encoder to two pins and have a manual trim wheel for digital trim. Or you can protect against run away trim by hitting any other button to override. Or you can drive an RC servo for heater controls with a pot on the panel. Or you can design a simple wig-wag lighting system and use the motor drivers to drive that. Or you can sample a sensor and indicate a fault LED. Or you can have a neutral trim button, which drives the trim servo(s) to neutral when pressed. Or you can slow down your servos with pulse width modulation when flaps are up, or when GPS is going fast (if you program it to read an external GPS NMEA sentence) or whatever.
The possibilities are endless, the code is really easy, and once mounted in a nice aluminum housing with good quality components and D-sub connectors, it becomes super easy to mount and wire.
Anyway, I'm going to build myself at least one and a spare and wanted to know if anyone else would be interested in a arduino compatible board that was ready to mount and wire.
Feedback is welcome, as I know there are some EE types floating around here.
This solution should be more reliable than a relay deck because the motor drivers are designed to handle inductive loads and not fry contacts, and because it's completely solid state.
I decided to go ahead and design the board for more generic use, and have the following:
2 motor drivers
2 channel digital pot
6 analog inputs or digital inputs/outputs
6 digital inputs/outputs
This offers the builder the ability, with a little code, to do cool things, like hook up a rotary encoder to two pins and have a manual trim wheel for digital trim. Or you can protect against run away trim by hitting any other button to override. Or you can drive an RC servo for heater controls with a pot on the panel. Or you can design a simple wig-wag lighting system and use the motor drivers to drive that. Or you can sample a sensor and indicate a fault LED. Or you can have a neutral trim button, which drives the trim servo(s) to neutral when pressed. Or you can slow down your servos with pulse width modulation when flaps are up, or when GPS is going fast (if you program it to read an external GPS NMEA sentence) or whatever.
The possibilities are endless, the code is really easy, and once mounted in a nice aluminum housing with good quality components and D-sub connectors, it becomes super easy to mount and wire.
Anyway, I'm going to build myself at least one and a spare and wanted to know if anyone else would be interested in a arduino compatible board that was ready to mount and wire.
Feedback is welcome, as I know there are some EE types floating around here.
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