Design - lynchej/Piano-Arm GitHub Wiki

#Embedded System

The embedded system used in this project is the servo motor. The servo motors can rotate 180 degrees, and can be controlled by the Arduino Uno. Below are the specs for the servo motors:

Servo Motor

Servo Specs

Note that the servo motors use 6V, not the 4.8V listed in the sepcs

#Arduino Uno Specs

Below are the specs for the Arduino Uno:

Arduino Uno Specs

#Frame Design

In order to construct the Piano Arm, the instructions to Hackaday's MeArm were used. The following components are necessary for construction:

  • MeArm Kit
  • DC Power Source
  • Arduino Uno
  • Wires
  • Breadboard
  • Weight

To construct the frame, follow the instructions from Hackaday.

After following the instructions in the above manual, the MeArm should look like: MeArm

The MeArm Kit is necessary as it is the frame of the Piano Arm. The Arduino Uno produces an output voltage of 5V, however for this project, I chose to use 6V as this would increase the speed and torque with which the Piano Arm could turn. To adjust for this, a battery pack of four AA batteries (6V) was used.

In order for the MeArm to be able to play the piano, it is necessary to increase the weight of the claw. I used some spare change to do this, but any weight (like washers) can be used. After adding the extra weight, your Piano Arm will look like this:

Piano Arm

#Circuit Design

The design of the Piano Arm circuit is relatively simple. For this stage, you will use the

  • Breadboard
  • Wires
  • DC Source
  • All four servo motors
  • Arduino

The circuit will look like: Circuit Design

Putting more than 6V into the servo motors can cause irreversible damage!

It is best to place the DC source in the rails on the side, and connect all of the servo motors in with connecting wires. Notice that with the servo motors, red is VCC, brown is GND, and yellow is the programmable port. This programmable port will connect with the Arduino Uno. Connect the servo motor that will control the claw to port 6 on the arduino, the motor for the right arm to port 9 on the arduino, the motor for the left arm to port 10, and the motor for the base to port 11.