Components (Actuators)

Many students come to my with questions regarding what sensors or actuators they should buy. This page will serve as a dynamic page for suggestions. Ideally this will be a starting point for student’s to gain familiarity with components before we meet and discuss their needs.

Since there are so many sensors and actuators, I have split the component pages into sensors and actuators.

Also note that I am not paid or endorsed by any company. I do see that students who purchase things for first year projects have more success buying from Sparkfun and Adafruit than Amazon and Ebay. This usually is because Sparkfun and Adafruit not only sell you something, but they also tell you how to use it. You may pay a little more for their items, but the time saved (and frustration thwarted) is worth it for most students.

Stepper Motors

I’ve had good luck with most stepper motors that have come into the Cave of Amazement (aka my office). Many of these have come from old printers that people have taken apart, but I have bought stepper motors from Adafruit and Sparkfun and they have served my needs well.

Sometimes the hardest thing with a stepper motor is figuring out the horse tail of wires that emerges from the motor. I often use my trusty “Practical Electronics For Inventors” reference to help me figure this out. A google search of “how to tell stepper motor wires” also yields many helpful results.

If you decode the wires, you also now know what kind of stepper motor you have and you ready for the next phase, making a Stepper motor joke! Get it? No? Ok, whatever. Once you know your type of stepper motor, you now have to figure out how drive it. Stepper motors rely on a distinct firing sequence in order to step, so you are always welcome to make your own circuit to step your motor. However the easiest way to drive a stepper motor is with a ready made circuit known as a driver.

If you have a small bi-polar motor, or a motor wired as bi-polar (o.e. 4,6, or 8 wire stepper motors), a driver that past students have had success with is the EasyDriver from Sparkfun. While not the most powerful driver on the market, it is easy to use and setup. A word of caution though – the Bildr tutorial is a good source for easy wiring, but the code doesn’t always work. This code (easydriver1step) will make it step one step… now it is up to you to get it to move more or less (hint – FOR loops are great).

Need to make a bigger stepper motor move? Students and I have had success with the Big Easy.