Pypilot working on my Nicholson 44

[xfactor99]

Sean and Kris, I've been reading this thread with great interest. I have a Nicholson 38 ketch with a 12v Neco installation and have a Tinypilot with Sean's Pypilot motor controller ready to connect up to the existing Neco relays once I manage to get down to the boat for a prolonged period. I'm very interested in not using relays and benefiting from motor current sensing, reduced power etc, but I'm not experienced enough with this stuff to fully understand. Are you using the IBT-2 motor controller or the Pololu one? How is it connected to the Pypilot and to the Neco motor unit? Do you have any diagrams? Thanks in advance for any tips and pointers.

Hey Phil, I can only encourage you to install the Tinypilot, as it is a far superior solution to the Neco control unit. Current sensing is great, but I think controlling motor PWM is waaaay cooler, as it lets you drive to motor much more smoothly and efficiently. I am not sure if Sean·s motor controller lets you drive the Neco to the max as I do not remember the max current. My Neco takes 24 volts and peaks around 200-300watts, so that should be around 20 amps on your 12 volt system. I use the IBT2 that handles up to 44 amps. My Neco on 24 volt only takes around 10 amps max, so the IBT2 is ample strong and probably long lived.

The Neco has a motor that is a bit more complex. There is a diagram and a description that was done by Daniele Fua, a really cool guy who was of much help to the community. You can find the documents posted earlier here in this thread. If your Neco control unit does not work anymore, you can just convert to the Tinypilot. I am a liveaboard cruiser and I opted for a switch box to be able to use both controls for redundancy. If you go for the full conversion, you can relatively easily reuse the end switches and the rudder angle sensor integrated into the Neco drive unit.

With the relays the motor is controlled at 100% juice and then forced to a halt, as the relays short the coil of the motor, thus magnetically braking the movement of the motor. This is a reliable but power hungry solution. The H-Bridge in Sean·s driver can nicely start and stop the motor and does not brake the motor like using the relays does. On the other hand there is a voltage drop on the H-Bridge but given how little the motor controller heats up during use, I do not think there is much energy lost there.

At the moment I am just trying to implement the last update of Sean, and drive the clutch with a PWM signal instead of an always-on signal when engaged. My clutch coil takes around 30-40 watts. It stays engaged with around 33% PWM so there is around 20 last watts to be saved with this last update.

Thanks for the update Kris. I've had long email exchanges with Daniele Fua, a really helpful guy. I went with Sean's motor controller planning to use the Neco relays, but the lower current consumption and better control of direct motor control seems like a good idea. The Neco drive unit is fused at 25 amps and probably peaks at around 20, so I don't think the motor controller will handle that. I'm looking at a Pololu unit to handle the current. Any info on the best way to control it would be really helpful.

Hi Phil

there are some diferent types of Pololu. I use the G2  24v19. you might like the G2 18v25, but htere are others.
I gues you can wire them also in diferent ways to the arduin with the running motor.ino. I use the RC mode. as I statet in erlier posts.
There is also a shematic how I conected. I dont use any feedback to the arduino and have the end of travel switches directly conected to the pololu. You can program the pololu to start speed and stallpower and many others. I also added a large capacitor as described in the pololu manual.
I know that Sean also has done larger controllers for hydrolic, so if you want to benefit mor easy from all the Pypilot has to offer maybe it is better to talk to Sean.

Greetings and save sailing
Andreas