My friend and I are currently working on a robotic vehicle project, and he had some spare steppers lying around from a previous project. Instead of using DC motors or servo motors, is it viably to use steppers to drive a small vehicle?
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2\$\begingroup\$ This has been asked in various forms before. Generally, steppers are unsuited for motive power due to the design compromises made to enable their open-loop indexing. If you don't need that, then they are heavy, inefficient, and have poor performance at speed, and if you do, it is often better to provide the positioning with closed loop electronics. On the cheap end, use a permanent magnet DC motor. On the fancier end, brushless motors are not all that different from stepper motors architecturally, but when closed loop sequenced by a cheap MCU yield better performance (especially at speed) \$\endgroup\$– Chris StrattonCommented Nov 7, 2015 at 17:55
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\$\begingroup\$ Thanks Chris, I'll make sure to keep that in mind with future builds. \$\endgroup\$– EnthurzanCommented Nov 7, 2015 at 17:59
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\$\begingroup\$ Steppers are usually about half the energy efficiency of a BL or regular DC motor (generalism alert) \$\endgroup\$– Andy akaCommented Nov 7, 2015 at 18:11
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\$\begingroup\$ You can, but please don't. Steppers are not designed for that type of use, and have many drawbacks and as Chris says, you will end up needing alternative closed loop encoders/position tracking anyway. \$\endgroup\$– KyranFCommented Nov 8, 2015 at 0:33
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Are you in mechatronics? I've used steppers in direct drive applications with some success. You can avoid most missed step events by driving them carefully, i.e. writing good code and implementing proper acceleration profiles + doing micro stepping when necessary to decrease torque ripple.
Having said all that, You should stick to a continuous rotation servo, or either of direct or geared drive through a DC motor for your project. You will draw less current, almost certainly, for a given speed. You will save the headache of writing a lot of extra code to get your steppers working optimally. In short, you don't want to have to worry about the particulars of using steppers if you also need to worry about the bigger picture, which is getting your project done well.
