# Three types of motors commonly used in counting robots

25/05/2019

Sometimes watching some robot videos or live games will have the urge to make robots by yourself, but most people don't have the expertise to know how to start.

Today, I will introduce you to some basic knowledge of robots, let you learn robots step by step, let's talk about the motors that are commonly used in robots. There are three types of motors commonly used in robots: ordinary DC motors, servo motors, and stepper motors.

1. A DC motor that outputs or inputs DC power, called a DC motor, is a motor that converts DC power and mechanical energy. When it is used as a motor, it is a DC motor that converts electrical energy into mechanical energy; when the generator is running, it is a DC generator that converts mechanical energy into electrical energy.

2. Servo motor The servo motor, also known as the actuator motor, is used as an actuator in the automatic control system to convert the received electrical signal into an angular displacement or angular velocity output on the motor shaft. Divided into two major categories of DC and AC servo motor, its main feature is that when the signal voltage is zero, there is no rotation phenomenon, and the rotation speed decreases uniformly with the increase of torque.

3. Stepper motor The stepper motor is an open-loop control element that converts an electrical pulse signal into an angular displacement or a linear displacement. In the case of non-overloading, the speed and stop position of the motor depend only on the frequency of the pulse signal and the number of pulses, and are not affected by the load change, that is, a pulse signal is applied to the motor, and the motor rotates through a step angle. The existence of this linear relationship, plus the stepper motor only periodic error without cumulative error.

It is very simple to control the change with a stepping motor in the control field such as speed and position. Beginners generally do not know much about MCU control motors. You can use the PWM signal output from the MCU to control the DC motor. You can try to control the stepper motor for higher control accuracy. For the motion drive of the trolley, a DC motor or a stepping motor can be generally used, and the servo motor is generally used on the robot arm to obtain a precise rotation angle.