Automatic System for Inflation and deflation of balloon

Hello, I appreciate any guidance that is offered I am planning of designing a system that can automatically inflate and deflate a balloon based on a min and max air pressure measured in psi. I will be using the arduino program to control an air compressor pump/motor, an l293D motor driver, a bread board, a pressure sensor, an air pump, a Pressure Sensor Honeywell ABPD, an led display and jumper wires. Thank you for any help. First time using a forum so if i'm doing it wrong please let me know

Is there more to it than "pressure below threshold, switch on pump, pressure above threshold, switch off pump"?

What is the LED display doing in there?

What's the use of that dinosaur (aka L293D)? Pumps don't tend to work well when reversed.

Why two air pumps?

I've deleted your other cross post @Donnelldj.

Cross posting is against the rules of the forum. The reason is that duplicate posts can waste the time of the people trying to help. Someone might spend 15 minutes writing a detailed answer on this thread, without knowing that someone else already did the same in the other thread.

Repeated cross posting will result in a suspension from the forum.

In the future, please take some time to pick the forum section that best suits the topic of your question and then only post once to that forum section. This is basic forum etiquette, as explained in the sticky "How to use this forum - please read." post you will find at the top of every forum section. It contains a lot of other useful information. Please read it.

Thanks in advance for your cooperation.

The basis of the project is to have the balloon fully inflate then deflate and then re-inflate continuously. The LED display will be used to show the pressure. & is there a better option rather than an air pump for this project (This would be a huge help). An apologies for the duplicate air pumps I was only planning on using one. Thanks for the help!

I am planning of designing a system that can automatically inflate and deflate a balloon based on a min and max air pressure measured in psi. I will be using the arduino program to control an air compressor pump/motor, an l293D motor driver, a bread board, a pressure sensor, a Pressure Sensor Honeywell ABPD, an led display and jumper wires. I will pay for assistance with the approach for this project.

An air pump can inflage it.
A solenoid valve can deflate it (taking advantage of the higher pressure inside the balloon).

I can help with this for you. The task is not too complicated.

You have listed an LED display. What is this for.

Will you be wanting to be able to set the upper and lower limits using the display and some rotary switches etc.

For deflating the balloon are you planing on running the compressor backwards or have a pressure release valve operated from the arduino.

Will the pump be using a non return valve or do you intend that the system continually tops up the pressure in the balloon if it gets too low etc.

Drop me a PM and we can chat a bit more about what you want.

Cheers Pete.

Thank you. Do you have any recommendation on a better motor driver to use besides the L293D.

Lots of better drivers like the TB6621FNG or DRV88xx drivers. No huge losses.

But for a pump normally a single MOSFET is enough. So again the question: why do you want to use a motor driver on a pump?

Is it possible to operate the system without the use of a motor controller?

Depends on your pump, and what you plan to do with it exactly.

Just on/off then as said you're better off with a single MOSFET as switch.

I've now merged in yet another cross post. This is your last warning @Donnelldj. If you cross post again I'm going to give you an account suspension.

Hmm seems he is making an offer of work but then skimming all the forums for free advice.

If you (the OP) are serious about this then just ask one of us to help.

Very likely the simplest method to do this would be to use a suitable sized syringe, and linear servo.

Syringe has to be bigger in volume than the final volume of the balloon: when the balloon is deflated, the air is at atmospheric pressure; when the balloon is inflated it's at higher pressure, so the volume becomes smaller.

Will work great with a sufficiently small balloon.

As OP is talking about compressors I was imagining fairly large sized balloons.

Donnelldj:
automatically inflate and deflate a balloon based on a min and max air pressure

That may not be the best approach, since the internal pressure of the inflated balloon may be quite close to 0 psig.

In the experiment described in the link below, the pressure inside the balloon is EQUAL to the outside with only a 0.2% error, after the initial peak (which is only 0.5% higher than ambient).

http://scipp.ucsc.edu/outreach/balloon/labs/InflationExp.htm