2019-06-18, 12:58 AM
Hi Skyeyedoc,
The ESPs are one direction only. The AIS does not listen and I never upload to the GPS. That could change. The ESPs are written up on my blog, KB7KMO.blogspot.com, as NEMA_WiFi_bridge if you are interested. A couple of posts. WiFi does use more power than other radio types. They connect to a wifi access point as a client then do UDP broadcast of the data on configurable ports, default is 10110 and 10111.
The TinyPilot is the course computer. It talks to the motor controller over optically isolated serial lines for reliability. The motor controller is currently an H-bridge controlled by an Arduino. An Arduinos is a small slower cpu with easy I/O. It listens for Seans's custom commands that are mostly turn a direction and how fast to turn. They measure current, rudder position and end stops to avoid over driving the rudder. They report back current, temp, optionally rudder position. Speed is controlled with PWM. The arduino is more imune to the noise generated by the motor and control than the raspberry. Also the arduino is powered by the same source as the motor, so the optical isolation is a good thing.
An H-Bridge is basically an electrically controlled 'double pole double throw'(DPDT) switch wired to reverse the 2 wires. A good H-Bridge for higher current needs higher current parts (MOSFETs, diodes, transistors, etc) which are more expensive. Sean's price for the two sizes of motor controllers is pretty reasonable.
I'm also stuck with finding a place to mount the tinypilot also. I put the hydraulic motor in the engine room, and the high current controller on the opposite side of the engine room wall away from potential water spray but only a few inches from the motor. But the cockpit arrangement is a long way from it by the way of running wires.
With the required reliability of the auto pilot communication and the occasional glitches with radio stuff, I will stick with wires.
The ESPs are one direction only. The AIS does not listen and I never upload to the GPS. That could change. The ESPs are written up on my blog, KB7KMO.blogspot.com, as NEMA_WiFi_bridge if you are interested. A couple of posts. WiFi does use more power than other radio types. They connect to a wifi access point as a client then do UDP broadcast of the data on configurable ports, default is 10110 and 10111.
The TinyPilot is the course computer. It talks to the motor controller over optically isolated serial lines for reliability. The motor controller is currently an H-bridge controlled by an Arduino. An Arduinos is a small slower cpu with easy I/O. It listens for Seans's custom commands that are mostly turn a direction and how fast to turn. They measure current, rudder position and end stops to avoid over driving the rudder. They report back current, temp, optionally rudder position. Speed is controlled with PWM. The arduino is more imune to the noise generated by the motor and control than the raspberry. Also the arduino is powered by the same source as the motor, so the optical isolation is a good thing.
An H-Bridge is basically an electrically controlled 'double pole double throw'(DPDT) switch wired to reverse the 2 wires. A good H-Bridge for higher current needs higher current parts (MOSFETs, diodes, transistors, etc) which are more expensive. Sean's price for the two sizes of motor controllers is pretty reasonable.
I'm also stuck with finding a place to mount the tinypilot also. I put the hydraulic motor in the engine room, and the high current controller on the opposite side of the engine room wall away from potential water spray but only a few inches from the motor. But the cockpit arrangement is a long way from it by the way of running wires.
With the required reliability of the auto pilot communication and the occasional glitches with radio stuff, I will stick with wires.
--
Larry - s/v Katie Lee Passport 45 Ketch (For Sale) - somewhere in Taiwan
Larry - s/v Katie Lee Passport 45 Ketch (For Sale) - somewhere in Taiwan