Electronics (motors and controllers)

electronics_num

We use servo motors with a controller to automate mechanical movements. For starters, you’ll need a servo motor and a controller.

1. Servo motors (with motor parts)
There are two types of servo motors: one rotates 180 degrees reciprocating movement and the other one rotates continuously. Many references explain servo motors; so here we list several links that explain the basics.

What is a servo motor?
How do servo motors work?
180° servo motor control guide
Continuous servo motor control guide

Besides the rotation type (180° or continuous), you will need to choose the motor size (standard or micro). A standard motor body is approximately 40x20mm (1.5”x0.8’’), and the micro size is 30x15mm (1.2”x0.6”). It doesn’t need to fit very accurately, as we’re using duct tape to attach the motor body to the part.

2. Controllers
2A. Arduino (with a usb wire and three wires for power, ground and signal)
You’ll need a controller to use servo motors. We use the Arduino microcontroller board. The Arduino software is free and supports Arduino controller products (as well as some other compatible products) to program servo motors. Here you can see the big picture of Arduino family products: https://www.sparkfun.com/arduino_guide

In the map, as long as a product includes PWM pins (which is applied to all products), you can use it to drive a servo motor and program it. If you’re not interested in investigating further functions that each advanced product provides, the Arduino Uno (or Sparkfun Redboard) is a good place to start.

You can read the basics of controlling servo motors (setting the speed and rotation angle of servo motors) here:
https://www.arduino.cc/en/Reference/ServoWrite
http://makezine.com/2014/04/23/arduinos-servo-library-angles-microseconds-and-optional-command-parameters/

For those using a 180° servo motor, start here:
https://www.arduino.cc/en/Tutorial/Sweep
For those using a continuous servo, remember that the command that sets the angle of a 180° servo motor (e.g.,ServoName.write(60)) instead sets the speed of a continuous servo. So, given a range of values from 0 to 180, a value near 90 stops the continuous servo motor, a value of 0 sets full-speed in one direction (“reverse”) and 180 sets the servo to full-speed in the other direction (“forward”).

You’ll need to use a USB cable to connect the controller to your laptop where you might have downloaded and installed the Arduino software from here to program your controller. You also need to use three “jumper” wires to connect the power, ground and signal of your servo motor to your controller. Jumper wires need male connectors on both ends because both the arduino controller and servo motors have female “headers”.

2B. LocoTap board
To facilitate the prototyping process focused on our purpose of using servo motors, we developed our own controller that doesn’t require programming. Using our LocoTap board, we can just plug in servo motors and rotate the knob or press buttons to control it. If you want to know more about LocoTap board, you can contact us.

3. Power supply
If you want to power your controller simply by a usb cable through a laptop, you don’t need an extra power supply. But if you don’t want to carry your laptop while making and displaying, you can use either a wall adapter or batteries with a battery holder.

You can find all above from electronic retail stores such as
Sparkfun, Adafruit, Makershed, Amazon