I'm completely new to Arduino and hardware projects but super excited to learn! I've done some basic Arduino tutorials, but this will be my first time trying to build a real system from scratch.
I'm working on a project where I will need to deliver quick, controlled air puffs (~20 PSI) using pressurized house air (from standard lab/industrial wall outlets). The goal is to control the puff duration (around 50-500ms) using an Arduino.
Here's what I think I need, but I'd really appreciate any guidance on where to start and how to put the pieces together.
What I Need Help With:
-Solenoid Valve Selection: I know I need a fast-acting solenoid valve, but I don't know what type, what voltage it should be, or which brands are reliable and Arduino-compatible
-Pressure Regulation: I assume I'll need to step down the house air pressure using a regulator to get a stable 20 PSI output. Does this sound right?
-Electronics and Power: I know I can't power the solenoid directly from the Arduino. Should I use a relay, a transistor, or something else? I've read about flyback diodes but I'm not sure when/how to use them
-Arduino Programming: For short air puffs, is it okay to use simple delay() commands, or should I use millis(s) or another method to get more precise timing?
Other Questions:
-Do you have any favorite solenoid valve models for this kind of project?
-Do I need to worry about pressure consistency over repeated puffs?
-Any general tips for a total beginner would be awesome!
Thank you all so much! I'm really excited to dive into this and learn as I go.
Note about Budget: Currently we have a large budget dedicated towards this project, so please let me know of any supplies I may need, regardless of price
While you are researching this get a copy of the Arduino Cookbook and go through each of the examples given.
What is standard, I have seen from ab out 60 to 130 PSIG. How accurate do the puffs including air volume have to be?
-Solenoid Valve Selection: Not knowing your area, suppliers, or volume of air required I suggest you work with a local industrial supplier. Most solenoids come both AC/DC and several voltages. These can range from very small to large pilot operated valves.
-Pressure Regulation: I assume I'll need to step down the house air pressure using a regulator to get a stable 20 PSI output. That is correct but depending on the volume and accuracy requirements you may also need an accumulator.
-Electronics and Power: I know I can't power the solenoid directly from the Arduino. That is correct but until the load (solenoid) electrical values are known this cannot be answered.
-Arduino Programming: For short air puffs, it depends on how accurate and repeatable this needs to be.
Do you have any favorite solenoid valve models for this kind of project? I cannot answer that as I have no idea how much air we are moving etc.
-Do I need to worry about pressure consistency over repeated puffs? That depends on your requirements.
-Any general tips for a total beginner would be awesome! Spend some time with the DuckDuckGo browser and search out these items.
Most air systems operate off a tank. That way, the pressure is constant. It, of course, has a compressor to keep it full. I know that my water valve came in 12VDC and 110VAC so I would make a small wager an air valve in 5VDC is a strong possibility. If not, learn how to use a MOSFET switch.
Your best approach by far is to break the project down into manageable pieces. Even those of us with 50+ years of experience still do that. For timing, use millis, avoid delay like the plague. There are tutorials here on the forum about state machines, which is your best design approach for this project. The main loop can be easily tested, as mentioned in small pieces, simply by commenting out all the other state actions.
This is a pretty straightforward project. The only concern should be finding a pneumatic solenoid valve with the required actuation time. I'd focus my efforts here. All the other concerns are trivially solvable.
Note that you'll probably have to go to a known manufacturer like Parker or Festo to get actual specs on response time. The cheap amazon supplier valves probably won't have that data.
Until this post I didnt know what to expect for solenoid valve response times. Found some SMC VQD1151 valves in my pneumatics drawer. They come in either 12 or 24V coil and have on/off times in the 4ms range.