ELEGOO 5 sets 28BYJ-48 5V Stepper Motor + ULN2003 Motor Driver Board for Arduino

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These stepper motors draw a lot of currents, hence a driver IC like the ULN2003 is required. We should look at the coil diagram below to see how to make this motor rotate. The modification for this is easy…really easy. Most information I can find online involves removing the blue cover on the stepper, and making a small cut to the PCB trace for the red (5v/12v) wire. I went ahead and did this on my first attempt and it does indeed work as intended.

The spec. sheet states that an A4988 needs > 8VDC power supply for your motor, i.e. you may not be able to run a 5VDC power supply for driving 5V 28BYJ-48 motors. Cheap– In applications where stepper motors would suffice, and using one could help you to realize better cost savings. Define the steps per revolution of your stepper motor—in our case, it’s 2048: const int stepsPerRevolution = 2048; // change this to fit the number of steps per revolution Firstly, we will include the Stepper.h library. This library provides useful functions that make it easy to control the stepper motor. #include I am unplugging 12V power now, because we are going to proceed to flash a sketch to the UNO in the next step.In this case I called the stepper motor ‘myStepper’ but you can use other names as well, like ‘z_motor’ or ‘liftmotor’ etc. Stepper liftmotor = Stepper(stepsPerRevolution, 8, 10, 9, 11);. You can create multiple stepper motor objects with different names and pins. This allows you to easily control 2 or more stepper motors at the same time. This Motor has a total of four coils. One end of all the coils are connect to +5V (red) wire and the other end of each coil is pulled out as wire colors Orange, Pink, Yellow and Blue respectively These kind of motors are commonly used in your DVD drives, Motion camera and other similar applications. The motor has a 4 coil unipolar arrangement and each coil is rated for +5V hence it is relatively easy to control with any basic microcontrollers. These motors has a stride angle of 5.625°/64, this means that the motor will have to make 64 steps to complete one rotation and for every step it will cover a 5.625° hence the level of control is also high. However, these motors run only on 5V and hence cannot provide high torque, for high torque application you should consider the Nema17 motors. So if you are looking for a compact easy to use stepper motor with decent torque then this motor is the right choice for you. Stepper motors can be driven in different modes and they have a specific gear ratio. Both factors have an influence on the number of steps per revolution. For this example, we shall drive the motor in a mode known as the full step mode, with each step corresponding to a rotation of 11.25 degrees according to the datasheet. That means there are 32 steps per revolution (360/11.25 = 32). In addition, the manufacturer has specified a gear ratio of 64:1 for the 28BYJ-48 stepper motor. How it works? After another half day's research and testing I have established that my motors are 4096 steps per revolution, achieved by 64 steps geared down by 64.

This stepper motor has a stride angle of 5.625 degrees. That means 28BYJ-48 will complete one revolution in (360/5.625) 64 steps by taking one step at a time and in one step it covers a 5.625-degree distance. However, the stepper motor can also be used in full-step mode. In full-step mode, the angle of each step is 11.25 degrees. That means the motor completes its one revolution in 32 steps instead (360/11.25). Put code in text document or favourite IDE and save it to test.py, or similar. Let's save the file directly on the desktop. The jumper next to power connections on the driver board can be used to disconnect power to the stepper motor. The 28BYJ-48 stepper motor requires 240mA current to operate and it also consumes power at an idle condition. Therefore, it is recommended not to power the 28BYJ-48 stepper motor directly from any microcontroller. Instead use an external 5 volts power supply. Interfacing Raspberry Pi Pico with 28BYJ-48 Stepper Motor and ULN2003 motor driver

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So start with a few simple codes. After some more practice to build up your confidence, be sure to try out more complex codes so that you can get the motor to do more things. Github, a platform with millions of open-source projects, is a good place to start looking for more example codes to play around with.

Hook the microcontroller to the A4988. I hooked the step pin to gpio18 on the Pi. And I hooked the dir/direction pin to gpio17 on the Pi. Then, hook the 5VDC from the Pi to the A4988, we could use an external 5v power supply to make this step safer. Piositive to positive-- Vmicro (5V) pin (second from the bottom) to microcontroller's/supply's 5v pin, and negative to negative-- GND on micro and supply(if used) to GND (bottom right pin) on the stepper driver. define MotorInterfaceType 8 // Define the interface type as 8 = 4 wires * step factor (2 for half step) The next step is to specify the motor interface type for the AccelStepper library. In this case we will be driving a 4 wire stepper motor in half step mode, so we set the interface type to ‘8’. You can find the other interface types here. If you want to run the motor in full-step mode (fewer steps per revolution), just change the 8 to 4. // Define the AccelStepper interface type; 4 wire motor in half step mode: This is because if the motor draws too much power, your Arduino can potentially be damaged. Do make sure that not more than 300mA is drawn out of your Arduino. If more power is needed, simply connect your driver board to an external voltage supply rather than using the Arduino’s onboard power supply. Manufacturer specifies 64:1. Some patient and diligent people on the Arduino forums have disassembled the gear train of these little motors and determined that the exact gear ratio is in fact 63.68395:1. My observations confirm their findings. These means that in the recommended half-step mode we will have:64 steps per motor rotation x 63.684 gear ratio = 4076 steps per full revolution (approximately).Precise Speed control– Precise increments in movements enable excellent control of rotational speed for process automation and robotics. The robot has no sensors for positioning, orientation, or a way to detect the edges of the table. Movement is controlled only by the number of pre-defined steps in each direction hard-coded in the sketch. The motors are running at approximately 8 volts DC and 15 RPM in this example. One thing that you cannot tell from the video is how quiet these little steppers run: StepperBot is very stealthy! Eventually, small errors add up over time and the bot falls off the table, but it typically runs for 10-15 minutes, before that: good enough for me! What is so special about steppers

We set a delay of one second. In the next two lines, we do the same thing again – setting the number of revolutions per minute and commanding the stepper to do a number of steps. However, this time, we set the speed to 6 rounds per minute and move the shaft in the other direction by setting a negative number of steps. This means that the motor will move 6 times faster, and should complete a full revolution in about 10s (60s / 6 = 10s). This tutorial was a getting started guide for stepper motors with the ESP32. Stepper motors move one step at a time and allow you to position the motor shaft at a specific angle.

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I used a breadboard and some jumper wires to connect the driver board to an external power supply. ULN2003 and 28BYJ-48 to Arduino Connections ULN2003 Driver Board Easy to control– Stepper motors can easily be controlled using a microcontroller like an Arduino. In fact, its ease of use has also been a major reason for its continued usage by stepper motor users.