Stepper motors are aptly named in that they move via “steps,” small increments, most commonly 400 steps and 200 steps (.9 and 1.8 degrees respectively). They create a very precise mechanical movement and this precision makes the stepper motor perfect for many applications such as: 3D printing, textiles, printing, gaming, robotics, YouTube music videos and many, many more. Stepper motors are a very useful tool because of how easy they are to use and the smooth movement they provide.
The origin of stepper motors isn’t exactly clear, and it’s in fact, somewhat confusing. The Royal Navy was said to have used stepper motors as early as the 1930s to move gun turrets, however there are other later developments that are also said to have played a role in the creation of stepper motors. Most of the credit goes to Frank W. Woods, who in 1924, patented a motor that made use of five coils to create step by step movement explaining how the navy would have used them in the 30s. Further credit is given to Karl Feiertag of General Electric who patented a “Permanent Magnet Brake” and this brake was said to have evolved into the hybrid stepper motors of today. Stepper motors are also said to be closely related to the appearance of the transistor semiconductor. Undoubtedly there was some overlap as one field of development enable the growth of others and technology improved to allow new designs and materials to be applied to other devices..
Although it seems very technical and precise at first glance, in actuality the function of a stepper motor is quite simple. A stepper motor consists of a central rotor that is permanently magnetized with north and south poles. Alternating coils surrounding the rotor are energized and de-energized to create an electromagnet thus attracting the magnetic rotor causing it to turn. The circle of electromagnetic coils ensures that as the rotor moves it’s at a set angle each time, step by step, thereby creating the precision that stepper motors are known for. Even with all this movement the wear on the motor is minimized as the moving parts don’t touch each other as they do when gears are used.
Stepper motors are used in many applications, the most recent of which is 3D printing – a great option due to the high precision needed in printing. But aside from all of the uses mentioned earlier, you can use stepper motors in more independent application, especially with SEEED Studio’s Raspberry Pi, BeagleBone Green and Arduino. This comprehensive guide walks you through how to control a stepper motor with Raspberry Pi and coding with Python. Similar configurations can be done with Beaglebone. While we sell Arduino, Arduino’s website is easy to navigate and contains some very helpful references to get you started, including a list of hardware you’ll need as well as schematic circuits and code. There are videos online as well.
The usefulness of stepper motors helped them to quickly find a place in many industrial uses and for small scale hobby applications. They’re simple in design, have a long life and move with a high degree of precision all of which makes them a very common piece to use. Here at EIO we have several styles of stepper motor and will be expanding that in the future. Make sure to share tell us all about your independent projects on Facebook or Instagram!