Hy there, I am developing an bench-top Photobioreactor. I was using a custom python program to read sensors and activate actuators for my reactor, and now I am moving to Mycodo to make it more user friendly.
I have it partially documented at https://github.com/VitorFrost/photobioreactor
(wiki has more details)
Thanks for making this task easier!
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That’s great. I’m currently in the process of putting together documentation for constructing an inexpensive peristaltic pump system for 5 to 16 pumps, with speed and direction control (depending on configuration), all controlled by 2 wires on I2C. This is for a larger project to develop a bioreactor system. I’ve been sourcing used bioreactor vessels from ebay. I think Mycodo will be a great controller without much modification, but there’s potential to add a few new features to really improve its ability to manage a bioreactor.
Great news!
Today I am using this type of module with PWM: Power Mosfet 15a 400w Dc 5v-36v Trigger Switch Module Relay - AliExpress
They work well, but can get hot.
What are you planing to implement? use an micro controller to communicate and deploy the PWM? Or an driver like TLC5940? (adafruit servo module? Adafruit 16-Channel 12-bit PWM/Servo Driver - I2C interface [PCA9685] : ID 815 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits)
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To be fair, I’ve tried first the Pioreactor project, but it is hard to use custom hardware.
They have a really good project, but it is not adequate to use other hardware (yet)!
I have just pointed out to them, maybe things gonna change: Easier way to intagrate custom sensors/actuators to make the software more versatile · Discussion #286 · Pioreactor/pioreactor · GitHub
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One PCA9685 16-channel PWM controller and between 3 and 8 L298N motor drivers. If you only care to pump one direction and at one speed (which volume can still be modulated with pauses), you only need one wire per pump and can control 16 pumps. If you want both directions w/o speed control, you need 2 wires per pump and can control 8. And if you want direction and speed, that’s 3 wires per pump to control up to 5 pumps.
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Oh, full H bridge gives me goose bumps from 2006~2008, when I was competing on robot wars! We where using Open Source Motor Control boards at that time. Thanks god bioreactor are not that extreme and don’t need to survive high current, High reverse voltage, impact, vibration, fire, etc…
Have you measured the current peak of those pumps?
How about the L9110 drivers? And DRV8835 (if max voltage is 11V)?
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I have several pumps but haven’t conducted any measurements.
I’ve considered other drivers, but keep coming back to the L298N for its high voltage range and current capacity, which enables it to run both small and large pumps.
I’m sure there are specific applications where a motor driver can be ideally matched with specific pumps, but what I’m working on will allow both small and large pumps to be controlled by the same motor driver. I’ll leave it up to the users to determine if they want to swap components. Learning the basic concept of developing a pump array is the most important aspect of what I’m trying to convey in the materials I’m developing.