COMMENT FONCTIONNE UNE TROTTINETTE ÉLECTRIQUE ?

 

Stepper motors are widely used in applications requiring precise control of position and speed, such as CNC machines, 3D printers, and robotics. Arduino, an open-source microcontroller platform, is one of the most popular tools for controlling stepper motors due to its simplicity and flexibility. This article will walk you through the process of programming two stepper motors with Arduino, covering essential concepts, wiring, libraries, and coding. The article will be keyword-rich to include terms like "stepper motors," "Arduino," and "program."

Table of Contents

1. Introduction to Stepper Motors
2. Bipolar vs. Unipolar Stepper Motors
3. Understanding the Role of Arduino in Controlling Stepper Motors
4. Essential Components for Programming Stepper Motors with Arduino
5. Wiring Two Stepper Motors to Arduino
6. Arduino Libraries for Stepper Motor Control
7. Writing a Basic Program to Control Two Stepper Motors
8. Advanced Programming: Synchronizing Motor Movements
9. Common Issues and Troubleshooting
10. Applications of Controlling Multiple Stepper Motors
11. Conclusion

---

1. Introduction to Stepper Motors

A stepper motor is a type of electric motor that rotates in discrete steps, offering precise control over its position, speed, and acceleration. Each rotation of a stepper motor consists of several "steps," which can be controlled by applying electric pulses to its coils in a specific sequence. This feature makes stepper motors ideal for applications where you need to control movement with high precision, such as in robotics or 3D printing.

There are two primary types of stepper motors: unipolar and bipolar stepper motors. Both can be controlled with Arduino, but they require different wiring and programming techniques.

2. Bipolar vs. Unipolar Stepper Motors

Unipolar Stepper Motor

A unipolar stepper motor has five or six wires and features a center tap on each of the motor’s coils. This allows the current to be switched through the coil in one direction at a time, simplifying the driver circuit. These motors are typically easier to control, making them more suitable for beginners.

Bipolar Stepper Motor

A bipolar stepper motor has four wires and requires the current to be reversed in each coil, offering more torque than unipolar motors but needing a more complex control circuit. Bipolar motors are widely used in demanding applications where torque is important.

When programming two stepper motors with Arduino, the wiring setup and programming logic differ slightly depending on whether you're using bipolar or unipolar motors.

3. Understanding the Role of Arduino in Controlling Stepper Motors

Arduino acts as the central control unit that sends the required pulses to the stepper motor driver or directly to the motor to initiate movement. The microcontroller can be programmed to adjust the number of steps, the direction of rotation, and the speed of each motor.

4. Essential Components for Programming Stepper Motors with Arduino

To program and control two stepper motors with an Arduino, you will need the following components:

• Arduino Board (such as Arduino Uno or Mega)
• Stepper Motors (bipolar or unipolar)
• Stepper Motor Drivers (such as the A4988 or DRV8825 for bipolar motors)
• Power Supply (suitable for the motor specifications)
• Connecting Wires
• Breadboard (optional for prototyping)

The stepper motor driver is an essential component that provides the required current and voltage to the motors while protecting the Arduino from overloading.

5. Wiring Two Stepper Motors to Arduino

Here’s how to wire two stepper motors to an Arduino:

For Bipolar Stepper Motors

1. Connect the stepper motor driver to the Arduino. The driver’s pins will typically include DIR (direction), STEP (step control), and EN (enable), as well as motor power (VCC, GND) and coil connections (A+, A-, B+, B-).
2. Power the driver using an external power supply that matches the voltage and current requirements of the motors.
3. Connect the stepper motor coils to the driver outputs.
4. Connect the driver’s DIR and STEP pins to separate digital output pins on the Arduino. Repeat this for the second motor using a different set of Arduino pins.
5. Enable the motor driver by connecting the EN pin to ground (or leave it floating if the driver does not use it).

For Unipolar Stepper Motors

Unipolar motors can be wired directly to the Arduino through an H-bridge driver like the ULN2003 or L298N. Connect the motor’s coils to the driver outputs, and use the Arduino to control the driver input pins.

6. Arduino Libraries for Stepper Motor Control

Arduino provides built-in libraries to simplify the programming of stepper motors. The two most commonly used libraries are:

• Stepper Library: The default library that comes with the Arduino IDE, ideal for basic control of stepper motors.
• AccelStepper Library: An advanced library that supports acceleration and deceleration, multiple motors, and more complex movement patterns.

To install the libraries:

1. Open the Arduino IDE.
2. Go to Sketch > Include Library > Manage Libraries.
3. Search for “AccelStepper” and install it.

7. Writing a Basic Program to Control Two Stepper Motors

Below is a simple example of controlling two stepper motors with the AccelStepper library.

In this example:

• AccelStepper(motorInterfaceType, pin1, pin2) creates a stepper motor object using the specified pins.
• setMaxSpeed() and setSpeed() set the maximum and current speed of the motors in steps per second.
• runSpeed() keeps the motors running at the set speed continuously.

8. Advanced Programming: Synchronizing Motor Movements

For more complex applications, such as CNC machines or robotics, you may need to synchronize the movement of both motors. You can do this by adjusting the speed dynamically or by using functions like moveTo() and runToPosition() from the AccelStepper library.

Here, the motors will move to their respective target positions before stopping.

9. Common Issues and Troubleshooting

When programming stepper motors, you may encounter issues like:

• Overheating: If the motors or drivers overheat, check the current settings and ensure proper ventilation.
• Missed Steps: This can be caused by incorrect step rates, insufficient power supply, or interference from other electronics.
• Motor Jitter: Ensure that the motor is wired correctly and that the step pulses are not too short.

10. Applications of Controlling Multiple Stepper Motors

Controlling two or more stepper motors with Arduino opens the door to a wide range of applications, including:

• CNC Machines: For controlling the movement of cutting tools along different axes.
• 3D Printers: For precise positioning of the extruder and build plate.
• Robotics: In robotic arms or platforms requiring synchronized movement.
• Camera Sliders: For smooth, controlled panning and tilting of cameras.

11. Conclusion

Programming two stepper motors with Arduino allows for high-precision control over movements in a wide range of applications. By using the right components, libraries, and wiring techniques, you can create systems that control motor speed, direction, and position. With tools like the AccelStepper library, programming multiple motors becomes straightforward, allowing you to achieve complex synchronized motion.