Published: February 13, 2018
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By: Steven Gamache, Cal Poly Pomona
Category: Mechanical Engineering
Hashtags: #Circuits #circuitsandelectronics #Controlengineering #Controls #dontletthesmokeout #whydidthesmokecomeout
In this project the objective is to control how fast a radiometer spins using only a lightbulb. The purpose of this project is to demonstrate the various control methods available to us as engineers.
For the first part we are to use open loop control, and the second closed loop with a tachometer (that we are also building).
Our design involves the use of an Arduino to control a transistor, with a 12v source, that controls a 30w lightbulb. The output of which should be linear, by our assumptions.
Some of the challenges of this project are:
1) Our primary transistor not having the amperage rating that was necessary.
The solution was to use multiple smaller transistors in parallel to carry the current necessary.
2) Stuttering on the output signal due to multiple gains
This one was more difficult to solve, but eventually i found that a capacitor on the 12v side smoothed out the signal.
3) Burning out transistors due to over current
the solution i found for this was to add aluminum tape heatsinks to each transistor as well as add more, for a total of 5.