SERVO MOTORS INTRODUCTION

A Servo Motor can be either a DC, AC or other type of motor and includes a device to know it’s position (ex.: potentiometer, digital encoder…).

Inside most Servo Motors you will find: A motor, gears, some type of limit stops that will limit the movement of the shaft, a potentiometer of some kind for position feedback and some integrated circuit to move the servo to a specific position.

A Standard Servo has around 180 degrees of motion. These can be modified to make them rotate 360 degrees or you can buy them already made this way.

The modification involves opening the Servo case, removing the limiting device and disconnect the potentiometer from the shaft.  Once done the Servo will rotate in either direction endlessly since it has no way of knowing it’s position anymore and there are no limit switches to stop it.

Most Servo Motors have three wires:

Black: Ground

Red: Voltage

White or Yellow: Control Wire.

To move a Servo you send a pulse to the control wire.  This process is referred to Pulse Coded Modulation.

Standard Servos expects to see a pulse every 20ms.  Depending on the length of this pulse the Servo will move to a specific angle.

For example a 1.5ms pulse will make the Servo move to the 90 degree position (which normally is the neutral or middle position).

A pulse shorter than 1.5ms will be move the Servo closer to 0 degrees and a longer one will move closer to 180 degrees.

Servos can have a lot of torque for their size and they also draw power in proportion to how hard they are working.  So if you project is not moving much weight than the Servo will not consume much energy.

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Control a ‘LOT’ of Servo Motors using a Joystick, Arduino and PCA9685 PWM Module

TUTORIAL Use the PCA9685 PWM Module to control a lot of servos simultaneously! – OVERVIEW We have seen in prior tutorials how to connect and control Stepper Motors. Stepper Motors are great for many projects but can get expensive when your projects needs

16 Channel PWM Expansion Board

Control Servos + PWM devices using this 16 channel PWM Expansion Board. PCA9685

When you run out of PWM Arduino-pins or are on a Raspberry Pi that doesn’t have PWM capability. With this PWM Expansion Board you can control up to 16 PWM driven devices from via 2 I2C pins. Can also be daisy-chained to give you up to 992 PWM outputs.

Features:

  • I2C controlled PWM/Servo driver board
  • Clock on board
  • Operating Voltage: 3.3V – 6V
  • 6 I2C Address Select Pins
  • Max Daisy-chaining: 62 boards for a total of 992 PWM outputs
  • Max PWM frequency: 1.6 kHz
  • Resolution: 12 bit
  • Configurable Output (push-pull or open-drain)
  • Output Enable (OE) allows you to turn off all outputs at once
  • Onboard Features:
    • Polarity Protection
    • Power Indicator LED
    • Optional capacitor solder point for smoothing
      • Address Select Jumpers

Control a ‘LOT’ of Servo Motors using a Joystick, Arduino and PCA9685 PWM Module – Tutorial

Visit https://brainy-bits.com/tutorials to download the code, library and get more information about our YouTube Tutorial. Facebook: https://www.facebook.com…

A simple method to control upto almost 1000 servos

In this video we are going to see the pca9685 which is a 16 channel 12 bit pwm driver to drive servos or leds . it is I2C : this means that you can control i…