Servo Motor MG996 360 Degree Continuous Rotation

High torque 50RPM continuous rotation servo for medium duty applications

DESCRIPTION

The Servo Motor MG996 360 Degree Continuous Rotation is a standard size servo with good torque and moderate speed.

PACKAGE INCLUDES:

• Qty 1 – MG996 360 Degree Continuous Rotation Servo motor with attached 11″ control cable
• Qty 2 – Arms/horns for various interface applications
• Qty 5 – Screws for mounting
• Qty 4 – Rubber and brass bushings for mounting

KEY FEATURES OF SERVO MOTOR MG996 360 DEGREE CONTINUOUS ROTATION:

• Standard (medium) size servo
• High torque of up to 13kg/cm
• 360 degree continuous rotation
• Metal (Brass & aluminum) gears
• Analog drive

These servos have good torque for the cost and work well for experimenting with robotic motor drives and similar applications that require a fair amount of grunt.  the MG996 has a little more torque than the otherwise very similar MG995

The high torque capability comes at the expense of fast speed of movement due to the gearing.  A 360 rotation takes about 1.2 seconds which is 50RPM.

Unlike normal servos that can be commanded to an exact position within a range of about 180 degrees, these servos rotate continuously in either direction with no ability to position to a particular position.  Think of them more like like DC motors with a motor controller built-in that powers the motor and that allows you to start/stop and control direction of rotation.  Speed can be adjusted somewhat when operating at near the midrange of the PWM.

These types of servos are handy for driving wheels on a robotic vehicle or if you just want to spin something around.

360 degree servo motors are comprised of a DC motor, gears and a small electronic control board.

These servos are driven by a PWM signal.  if using the Servo.h library as shown below, a command of about 90 will cause the servo to stop.  A value of 0 will cause it to turn in one direction at full speed and a value of 180 will cause it to turn in the other direction at full speed.  Values close to 90 will cause the motor to run at something less than full speed.

Motor Connections

The built-in cable has a 3-pin female connector that is usually mated with a male header.

1×3 Connector

• Brown = Ground
• Red = 5V
• Orange = PWM Signal

OUR EVALUATION RESULTS:

In our testing these MG996 servos have been fairly robust.

Construction is reasonable.  The servo opens easily with 4 screws, just be careful not to let the gears fall out or it is a bit of a puzzle to put them back together.  The picture here is of the standard 180 degree servo, so it has a mechanical stop pin on the main shaft to limit the rotation but is otherwise the same.

Due to the metal gears, they can be somewhat noisy, but not too bad.  On the plus side, if you are going for a mechanical sounding killer robot, you won’t have to worry about needing to add any artificial sound effects.

Though the label says ‘DIGI HI-SPEED”, the servo is neither digital or high-speed.

The servo runs on 5V nominal with a current draw of about 20mA at idle and 170mA to 400mA under no load operation.  Current draw can get up to a maximum of about 1.3 to 1.5A under a stall condition.  It is not recommended to try to power one of these directly off of an Arduino board as it is likely to cause erratic behavior.  It is always best to drive them directly off of a separate power supply.

The program below simply runs the servo forwards for 3 seconds, pauses and then runs in reverse for 3 seconds.  The servo is connected to pin 9 in the example, but this can be any PWM capable pin.

Servo Motor MG995 360 Continuous Rotation Test Program

/*
  Exercise 360 degree Servo motor
  Simply runs servo in one direction for 3 seconds, stops and then reverses direction
  Uses built-in Servo.h library
*/
#include "Servo.h"
#define SERVO_PIN 9   // Can use any PWM pin

Servo servo;          // creates servo object used to control the servo motor
//===============================================================================
//  Initialization
//===============================================================================
void setup()
{
  servo.attach(SERVO_PIN); // assigns PWM pin to the servo object
}
//===============================================================================
//  Main
//===============================================================================
void loop()
{
  servo.write(0); //Spin in one direction
  delay(3000);
  servo.write(90); // Stop
  delay(500);
  servo.write(180);  // Spin in opposite direction
  delay(3000);
  servo.write(90);  // Stop
  delay(500);
}

BEFORE THEY ARE SHIPPED, THESE MOTORS ARE:

• Servo is operated under no load condition back and forth for 5 minutes to verify basic operation.

Notes: 

1. None

TECHNICAL SPECIFICATIONS