I am a 2nd year design engineering student working on a design project where we are tasked with automating the movement of a rainfall simulator. One of our design ideas consists of two small motors running perpendicular to each other with the movements based on a random number generator. I was told that this would be fairly easy if we used a Siemens Program Logic Controller, but we have a very limited budget so I thought I would check out other options.

I am not familiar with the Arduino or much of anything to do with programming so I thought it would be beneficial to ask for advice from some people who know what they are doing. I attached an initial sketch of the idea and a picture of the rainfall simulator to hopefully clarify what I am hoping to accomplish. The most the device can move from its rested state is only 0.5".

Is this a path worth working towards? Or is this not the proper choice of equipment?

Any advice would be greatly appreciated!



enter image description here enter image description here

  • What is a PLC? And it is not clear, what exactly you want. You could easily generate a random number between -1 and 1 and let the motor move for a time based on that, or with a speed based on that. I also don't understand, what exactly a "rainfall simulator" does here. How big are the motors, that you want to control (in terms of needed current and voltage)? You should give us more information
    – chrisl
    Commented Nov 20, 2019 at 11:39
  • 1
    Thanks for letting me know it was unclear! I added a sketch of the idea and a picture of the rainfall simulator. I don't currently information on current and voltage as it is still a conceptual idea and we are in the process of figuring everything out. Commented Nov 20, 2019 at 11:53
  • I'm not sure, what I should write as an answer here, because your question is very broad. Surely you can build this with an Arduino and depending on your exact requirements, it will be rather easy. But that is too few for a real answer. So I suggest, you ask mores specific
    – chrisl
    Commented Nov 20, 2019 at 12:37
  • Random is hard. Pseudo-random is easy. Commented Nov 20, 2019 at 19:41

1 Answer 1


Leaving your mechanical equipment uncommented *), an Arduino itself cannot drive 7.4V 1A Stepper Motors. An Arduino itself cannot drive any motor. You need a sufficient power supply and motor driver electronics. And there's a vast amount of different devices to choose from.

But then, the answer to "is it possible (random, two motors, moving independently)" is yes.

*) Well, regarding "uncommented" : 200 lbs is quite heavy to simulate/produce a few raindrops. Small motors won't move such gear as in your pic.

  • The Rainfall simulator itself can weigh a maximum of 200lbs when it is completely filled with water. The rainfall is produced through a vacuum in the tanks and drips out of small holes by itself. Currently the lab tech needs to stand beside the machine and push it every so often. The task we are assigned with is just moving it side to side in a "random" sense. Thank you for your answer though as that was all I was looking for at the time! I will continue to pursue this design with my group with the information you provided. Commented Nov 20, 2019 at 16:18

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.