I am looking for a high-speed stepper motor that can do at least 350RPM.
I am confused with the voltage rating: 2.7 V (Pololu item #: 1209). I need a motor that can handle 12 or 24 volts. I will be using the DRV8825 (Pololu item #:2133).
Can someone help me with what driver and what stepper motor I should use?
Thanks, big time ( ͡° ͜ʖ ͡°)
Many of our stepper motors should be able to handle speeds that high in some capacity, but I cannot make a more specific recommendation without knowing more details of your application, like how much torque you need for your load and how you plan to power the motor. I suggest starting by characterizing your load as best you can then looking at the holding torque column of the comparison table on our stepper motor category page to narrow down what motors might be in the right ballpark. From there, look at the pull out torque curves in the motor datasheets (they are available on each motor’s product page under the “Resources” tab) for more detailed information. Keep in mind that the holding torque value can be very different from how much load the motor can handle at speed, so do not work off of that value alone.
It is generally better to select a stepper motor driver after you choose the motor. Fortunately, if you are already committed to the DRV8825, there is a decent chance it will work for your motor. Keep in mind it is okay to power your stepper motor driver from a higher voltage source than what your stepper motor is rated for as long as you set the current limit appropriately. In fact, there are actually several benefits to doing so. There is a more detailed explanation on the DRV8825 product page under the FAQs tab.
If you post what motors and drivers you are considering along with more information about your setup and anticipated load, then I might be able to let you know if your selections seem reasonable.
I am working on an impact tool ( tool weight appx 2.8 LBS ) .where angular momentum is the driving requirement, more than the holding torque. The motor swings the tool 60Deg from a home position (30Deg to 90Deg).
The design is wide open for the stepper motor voltage. As the design sits right now ( subject to change ) is 24V, but thinking of using 12V instead. I’m confused by the motor voltage of 2.7V. What does that mean?
I am not committed to any driver so any driver that can be controlled with a Raspberry PI computer (to control impact force ) will be OK. The only requirement is the drive has to be the same PCB footprint and pin out as the DRV8825.
Yes, I understand the importance of Vref setting requirement.
As described in the FAQ I linked to in my last post, the voltage rating is just the voltage at which each coil draws the rated current. So, as long as you are using a current limiting stepper motor driver (like any of ours) you should generally want your power supply to be at least as high as the rated voltage or higher so you can access the maximum possible power from your stepper motor.
By the way, applications that require precise timing, like generating step signals for stepper motor drivers, can be tricky with a Raspberry Pi. They do not have the same form factor as our DRV8825 carrier, but you might consider using one of our Tic Stepper Motor Controllers since they support a variety of control interfaces that I expect to be easier to implement with a Raspberry Pi, like USB, TTL serial, and I2C. In fact, we have a Linux version of our Tic control center software for Raspberry Pi, and the Tic user’s guide includes a few Python examples.