I want to develop an automated aquarium which handles feeding, cleaning and monitoring the water quality.
Coming from a software background I think I can handle the coding side of things.
My problem is that I cannot figure out what I need to buy to get the hardware working.
So I would like to ask for help in selecting the components needed as well as advise on if I can do everything with one MCU or
if I need more.
Here is the list of I/O devices I want to control.
11 drip valve (Peristaltic Liquid Pump 6V or 12V)
5 water valve (Solenoid Magnetic Latching Valve 6V or 12V)
1 air pump 6V or 12V
1 air pump 6V or 12V
1 water pump 6V or 12V
1 temperature sensor 5V
1 ec sensor 5V
1 ph sensor 5V
1 weighing scale 6V or 12V
and if that was not enough I need to control 16 AC sockets.
To control the above, my current thought is to use a Rasbury PI with WIFI as controller to an Ardurino UNO via I2C.
Among the things confusing me, I have found Adafruit 16-Channel 12-bit servo shield as well as driver. Which should I use?
Also there is one called a servo HAT for the raspberry pi itself. Ideally I want the board/shield to handle the PWM signal rather
the MCU.
The same goes for the relay board I think I need to handle controlling AC powered sockets.
Lastly I am in the UK and have been trying to find someone who could mentor me on the project, as I think a few hours is all I
need to figure out what I need, so is there any contacts you can recommend. I am willing to pay if needed.
Ideally I want the board/shield to handle the PWM signal rather
the MCU.
Why? Handling the servo pulses in hardware is much better then handling them in software.
The same goes for the relay board I think I need to handle controlling AC powered sockets.
Turning a pin on or off is far easier than generating the communications needed to tell some other device to turn a pin on or off. I don't understand why you are trying to off load dirt simple stuff from the microcontroller that will be doing nothing 99% of the time.
Why? Handling the servo pulses in hardware is much better then handling them in software.
Am I getting this wrong? The shield is designed to handle the hardware pulses freeing the MCU to do other tasks. Also shields should handle the powering of the servos.
I thought that the number of servos, etc. would be a strain on the MSU ( power and processing time) as well as requiring resistors, etc.
I hoped that using shields for the task would eliminate the need for a circuit. As I said before I was hoping for a plug and play solution as I know next to nothing about electronics.
The problem I have is I don't think it can handle the number of valves I need as well as lacking the AC sockets I needed. Also the method of checking the water level does not seem as accurate as weighing the water.
However the PH sensor seem perfect, thank you.
Just for background, there are multiple tanks, with a central tank used for filtering and cleaning the water and is to be used by a friend of mine in a wheelchair so the hardware I listed above is the exact components needed for the project.
Do you think a single UNO can handle the list of devices I listed or would I need more than one. Should I use the UNO or mega? As I said the hardware choices seem to be many and I would prefer not to spent too much time selecting what I need without knowing anything?
As I said above ideally I wanted someone to help spec the exact hardware so I can get on with writing the code.
