This forum uses cookies
This forum makes use of cookies to store your login information if you are registered, and your last visit if you are not. Cookies are small text documents stored on your computer; the cookies set by this forum can only be used on this website and pose no security risk. Cookies on this forum also track the specific topics you have read and when you last read them. Please confirm whether you accept or reject these cookies being set.

A cookie will be stored in your browser regardless of choice to prevent you being asked this question again. You will be able to change your cookie settings at any time using the link in the footer.

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
drive questions.
#1
Bought a used octopus  1212lar12 for my Pearson 323. 32 feet and about 13,000 pounds.
Very overkill, on bench looks good so far.
https://octopusdrives.com/products/hydra...ar-drives/
No load current is 3 amps.
They claim 4-6 amp and normal usage. 12 amps at max rated thrust and 19amps stalled.

This is on the high side for the Sean's motor controller I have.
I'm thinking of repackaging, adding heat sinks and clutch.

Is there an optimum no load hard over time?
I doubt if light weather load will change much from no load.
Pump is adjustable and can be pretty fast.
They specify a 10" tiller arm and I'm thinking of shortening a little, probably 9"  to save a little rudder movement when docking.
That will make it a little faster.

Does it make sense to make fast as possible and  pwm  motor if needed.?

John
Reply
#2
yes, faster is better, but there is a slight efficiency switching loss in pwm, so running full speed maybe gives 5-10% more efficiency, but whatever.


hard over time of 6 seconds would be good, prefer no longer than 10. If you can get it down to 3-4 seconds, let us know all about it! Faster basically means you can deal with more difficult conditions, but there is likely an optimal speed for efficiency too, so the ideal drive could actually change the distance it engages from the rudder shaft to minimize power consumption, but no one actually does this... few people have variable pitch propellers either.
Reply
#3
(2020-08-28, 03:50 PM)johnm Wrote: Bought a used octopus  1212lar12 for my Pearson 323. 32 feet and about 13,000 pounds.
Very overkill, on bench looks good so far.
https://octopusdrives.com/products/hydra...ar-drives/
No load current is 3 amps.
They claim 4-6 amp and normal usage. 12 amps at max rated thrust and 19amps stalled.

This is on the high side for the Sean's motor controller I have.
I'm thinking of repackaging, adding heat sinks and clutch.

Is there an optimum no load hard over time?
I doubt if light weather load will change much from no load.
Pump is adjustable and can be pretty fast.
They specify a 10" tiller arm and I'm thinking of shortening a little, probably 9"  to save a little rudder movement when docking.
That will make it a little faster.

Does it make sense to make fast as possible and  pwm  motor if needed.?

John

Hello johnm

I bought the same ocotpus as you. Can you tell me how you installed the clucth system with Pypilot. I really don't know how to do it. Can you help me? 

NousVoila (Pierre)
Pierre 
Reply
#4
(2022-03-16, 09:02 PM)NousVoila Wrote: Hello johnm

I bought the same ocotpus as you. Can you tell me how you installed the clucth system with Pypilot. I really don't know how to do it. Can you help me? 

NousVoila (Pierre)
Started with motor controller that did not have clutch output.
Added an external daughter board with fet, resistor and fuse.
I think the new motor controller has the needed hardware to drive the clutch.
Changed program to pwm the clutch.
This is from memory and and can dig up details.

It works very well. Usually draws about 4 amps when running.
It is a bit noisy. I connected ram to cockpit sole and it  wants to vibrate the cockpit sole.
Mostly an issue when going down wind with large waves.
Made some changes to mounting that helped.

John
Reply
#5
(2022-03-18, 01:18 AM)johnm Wrote:
(2022-03-16, 09:02 PM)NousVoila Wrote: Hello johnm

I bought the same ocotpus as you. Can you tell me how you installed the clucth system with Pypilot. I really don't know how to do it. Can you help me? 

NousVoila (Pierre)
Started with motor controller that did not have clutch output.
Added an external daughter board with fet, resistor and fuse.
I think the new motor controller has the needed hardware to drive the clutch.
Changed program to pwm the clutch.
This is from memory and and can dig up details.

It works very well. Usually draws about 4 amps when running.
It is a bit noisy. I connected ram to cockpit sole and it  wants to vibrate the cockpit sole.
Mostly an issue when going down wind with large waves.
Made some changes to mounting that helped.

John

(2022-03-20, 10:44 PM)NousVoilacan you give me more information about the external daughter board with fet, resistor and fuse that you have installed and a connection diagram. I don\t know much about electronics. Or a link to some examples of this. Wrote:
(2022-03-18, 01:18 AM)johnm Wrote:
(2022-03-16, 09:02 PM)NousVoila Wrote: Hello johnm

I bought the same ocotpus as you. Can you tell me how you installed the clucth system with Pypilot. I really don't know how to do it. Can you help me? 

NousVoila (Pierre)
Started with motor controller that did not have clutch output.
Added an external daughter board with fet, resistor and fuse.
I think the new motor controller has the needed hardware to drive the clutch.
Changed program to pwm the clutch.
This is from memory and and can dig up details.

It works very well. Usually draws about 4 amps when running.
It is a bit noisy. I connected ram to cockpit sole and it  wants to vibrate the cockpit sole.
Mostly an issue when going down wind with large waves.
Made some changes to mounting that helped.

John
Pierre 
Reply
#6
With Sean's controller 6-8A,  the Clutch output is available at D11 of the arduino (pin 14).

Here is the diagram of the electronic interface that Sean used with the hydraulic controller at the time.


Attached Files
.pdf   Cluch.pdf (Size: 348.48 KB / Downloads: 66)
Reply
#7
(2022-03-22, 02:41 PM)Jean-Marc Douroux Wrote: With Sean's controller 6-8A,  the Clutch output is available at D11 of the arduino (pin 14).

Here is the diagram of the electronic interface that Sean used with the hydraulic controller at the time.

Was just going to upload my schematic but yours is probably more appropriate.
In mine I added a attiny85 that pwms the clutch. It works but managed to modify the the motor controller to do the pwm so I bypass the attiny85.
Can upload schematic and codes if anyone is interested.

I personally consider some sort clutch holding current control a necessity.
Draws over 12 watts just to hold the clutch in. It gets crazy hot.  I'm down to about 1.5 watts to hold.
As an alternative can just put resistor and capacitor in parallel in series with the clutch. That will get down to about  4 watts, mostly dissipated by the resistor.

Pierre  you may want to just buy the new motor controller with the clutch output and rudder position. It's pretty reasonably priced.
I'm thinking of buying a new one to make my setup simpler.

John
Reply
#8
(2022-03-23, 04:58 PM)johnm Wrote:
(2022-03-22, 02:41 PM)Jean-Marc Douroux Wrote: With Sean's controller 6-8A,  the Clutch output is available at D11 of the arduino (pin 14).

Here is the diagram of the electronic interface that Sean used with the hydraulic controller at the time.

Was just going to upload my schematic but yours is probably more appropriate.
In mine I added a attiny85 that pwms the clutch. It works but managed to modify the the motor controller to do the pwm so I bypass the attiny85.
Can upload schematic and codes if anyone is interested.

I personally consider some sort clutch holding current control a necessity.
Draws over 12 watts just to hold the clutch in. It gets crazy hot.  I'm down to about 1.5 watts to hold.
As an alternative can just put resistor and capacitor in parallel in series with the clutch. That will get down to about  4 watts, mostly dissipated by the resistor.

Pierre  you may want to just buy the new motor controller with the clutch output and rudder position. It's pretty reasonably priced.
I'm thinking of buying a new one to make my setup simpler.

John

I made a pilot with Andreas' board with the IBT2 not a clone, a real one and with an ICM 26948 from Adafruit. I made the boards with his gerber files, etc.
I have 2 of them made and one for a friend. I use Pi Zero W 2

https://open-boat-projects.org/en/pypilot

I'm using his motor.ino (Andreas) with Stelian's image and everything works fine. I'm trying to include the clutch control. I'm pretty good at computers but I'm not good at programming a controller (Nano) because I don't know anything about electronics.
At worst, I will install a manual switch for the clucth.


Translated with www.DeepL.com/Translator (free version)


Attached Files Image(s)
   
Pierre 
Reply
#9
(2022-03-23, 04:58 PM)johnm Wrote: I personally consider some sort clutch holding current control a necessity.
Draws over 12 watts just to hold the clutch in. It gets crazy hot.  I'm down to about 1.5 watts to hold.
As an alternative can just put resistor and capacitor in parallel in series with the clutch. That will get down to about  4 watts, mostly dissipated by the resistor.

Pierre  you may want to just buy the new motor controller with the clutch output and rudder position. It's pretty reasonably priced.
I'm thinking of buying a new one to make my setup simpler.

John

The newest motor.ino codes support pwm on the clutch output, and the duty cycle is configurable in the pypilot settings.   So it does apply full power to the clutch for a few hundred milliseconds, but after reduces to pwm with set duty cycle to drop power.
Reply
#10
(2022-03-24, 01:11 AM)seandepagnier Wrote: The newest motor.ino codes support pwm on the clutch output, and the duty cycle is configurable in the pypilot settings.   So it does apply full power to the clutch for a few hundred milliseconds, but after reduces to pwm with set duty cycle to drop power.

Sean

Good to hear you have pwm clutch in the new motor.ino :-)
Searching found your post with this:
pypilot_client servo.clutch_pwm=50
if pypilot is running
if not running edit ~/.pypilot/pypilot.conf

Does pypilot need to be updated  for this to work?
Is that percent or with respect to 255 on full?

Looking at the photo of the new motor controller in your store I do not see clutch output.
Is it on the board or is the $8 clutch option external?

John
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)