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12

Servos do have several advantages; but, they are more expensive and more difficult to control. Generally, a servo motor is a DC motor but with an encoder to provide position feedback. A circuit (can be a computer) then compares the actual position (from the encoder) against the commanded position and uses the error to determine how much power to put to the ...


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The main reason why stepper motors are used is their low price. Small stepper motors (NEMA 17 and smaller) are powerful enough for 3D printers because the mass is so small. These motors generally require a maximum of 2 amps of current. 2 amps is small enough that control chips with all the circuitry and drive electronics can be manufactured as an integrated ...


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Servo is best when you primarily provide an exact position to go to, sounds like a human arm isn't it? However, number of positions is sometimes overwhelming. Think about a painting, is it easier to draw point by point or just throwing the pencil relatively with instincts? That is why you need less computing when using stepper motors because they just step ...


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You can get "stepper replacement" servo drives that supposedly put all the needed control in the drive, and accept ordinary stepper inputs. Those should make the servo-drive a "drop-in" option on anything that uses stepper drives. That said, I've seen an affordable CNC router system based on steppers turned into a much more expensive system based on servos, ...


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The mistake in your reasoning is assuming no microstepping. Most 3D printers use 16 microsteps, and in my experience with both cheap A4988 drivers and nice TMC2209 drivers, microstepping is quite accurate. As part of an answer to a question I asked, you can see a test print showing single-microstep features. My motors have 1.8° step angle, yielding 3200 ...


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You can use a magnetic position encoder. AS5048B High Resolution Position Sensor 14-bit rotary position sensor with digital angle (interface) and PWM output 14 bit means 16k steps/rotation. With a stepper which does 200 steps/rotation and 16x microstepping, you will need only 11 bit, so you have plenty of extra accuracy you can use to filter noise. You may ...


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Have a look at the boards pinout: You'll need 3 pins for each additional driver - enable, step, and dir. The AUX-2 connector should give your 8 GPIO pins for that, without losing other functionality like the display. You might also be able to wire your Y axis motors in series, saving one stepper driver. You could then use E1 and three of the four servo pins ...


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The gearbox approach is solid, but it will be 100x slower, and you said you wanted speed.


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The basic difference between a traditional stepper and a servo-based system is the type of motor and how it is controlled. Steppers typically use 50 to 100 pole brushless motors while typical servo motors have only 4 to 12 poles.


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I think using these technologies is possible, and may be better than stepper motors, but by using these you loose the main advantages of the steppers : the simplicity and the cost. When you use steppers, you assume your motors are strong enough to don't loose any step, and you "just" command them. Steppers are not so expensive and are compacts, so your 3D ...


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