Stepper Motors

Stepper motors need to be sent pulses to work. Typically a pulse might last for 500 microseconds.

A pulse will move the motor one step. Typically there are 200 steps to one revolution, so each pulse rotates the motor through 1.8 degrees.

Stepper motors allow you to position things with an extreme level of precision. They control the position of the print head in a 3D printer for example. You control the position by the number of pulses you send, and the speed by the length of each pulse;

At Pak we are using the Toshiba TB6600 stepper motor driver to control our stepper motors (because they need more current than the 293 H-bridge chip can provide. However, if you have a small stepper you could control it using the 293). The TB6600 makes it very easy to set the number of steps per revolution using switches on the side of the unit.

Here is a link to an example for how to wire up the motor to the driver and to the Arduino.

It also has some code to show you how to program the motor. There is no library. The stepper motor controller makes controlling the motor directly from the Arduino quite simple.

Note that the 'on' time for the pulse in the code this example is given as 50 microseconds. This is way too short. Try using 500 microseconds.

https://www.dfrobot.com/wiki/index.php/TB6600_Stepper_Motor_Driver_SKU:_DRI0043#Quick_Start

Also that site does not tell you how to set the dip switches on the end of your stepper motor controller. They need to be set as shown in the photo below:

If you are using the TB6600 stepper driver: make absolutely sure you connect the power the right way round.

Also, the stepper motor will not run properly unless you power it with 16V. This means you need to use two battery packs in series. However, the Arduino can not take more than 12V so you need to wire up your circuit like this, so the Arduino gets 8V and the Stepper motor controller gets 16V

The red switch in the middle is a double pole,double throw meaning it is two switches alongside each other. This is necessary in order to ensure that power from both batteries is cut when the switch is turned off.

Be careful to make unconnected ends safe at all times because if they touch you could easily start a fire.