The best replacement for servo is stepper.

The best alternatives to servo are rated as following:
★★★★★  stepper
★★★  motor
★★★  stepper motor
★★  stepper cnc
★★  vfd
★  stepper motors
★  ai focus
★  actuator
★  dc motor
★  analog
★  brushless gimbal
★  castrol
★  al focus
★  step motor
★  dc servo
★  analog servo
★  brushless
★  induction motor
★  relay
  gear motor
  metrics
  brushless motor
  proportional valve
  one shot
  step
  proportional
  shift kit
  non servo
  ac servo
  stepper cnc router
  hitec servo
  solenoid
  stepper motor cnc
  duo servo

Your alternative for servo is not listed? Suggest!
Speaking about servo, one probably shouldn't forget about arduino.

Other search terms related to servo and their ratings are:
★★★★★ arduino
★★★ potentiometer arduino
★★ arduino motor shield
★ gyro
button arduino
jr receiver
You have in mind a companion for servo and it is not yet here? Propose!



Google Trends

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servo
stepper
motor