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Suitable servo



Looking for a suitable servo or stepper

Need 5 things together, small (about miniservo size) programmable motor with rotation in both directions and I guess (stepper solenoid brake) for fixed positions after stopping and it’s not very long-range turns but must be fast, for example this sequence in 2 or better 1 seconds:

from start position 360 ° degrees left
then back to start position and 0.72 ° right
then back to start position and (3 times) 360 °
then again from start position left 360 ° (8 times) + 20 °
then back to start position and left 360 ° (7 times) + 87 °

Something like this… So which device can work this way for me or I need something else?



We do not make anything that specifically does that, but if you need multiple turns, a stepper motor might be one way for you to build something that does. A servo would probably not work because they cannot perform an arbitrary number of turns or (in the case of continuous rotation servos) do not allow precise positioning. Also, it might be difficult to find one that works at the speeds you mentioned.

Our Sanyo Miniature Stepper Motor is the smallest stepper motor (by weight) we currently have in stock. If you determine the torque you need to complete the motions you described, the pulse rate-torque characteristics graph in the datasheet for the stepper motor should give you an idea of whether the stepper motor you are interested in can handle the mechanical load. You can find datasheets for the stepper motors we carry on the “Resources” tab of their respective product page. You can read more about how to determine the torque needed to move a load with a given acceleration in the “Force and Torque” post on our blog.

In addition to the stepper motor, you will probably need a stepper motor driver to power the coils on the stepper motor and something like a microcontroller to control the motion.