Abstract

The goal of this project was to create a reactive-lighting Musical Instrument Digital Interface (MIDI) standing drum set. The Decent Rather Unintelligent Mechanical System (D.R.U.M.S.) is a device appearing as a large standing drum set. The D.R.U.M.S. utilizes the Ableton music production software to interpret electrical signals, coming from individual D.R.U.M.S. modules, as MIDI notes.

Introduction

The D.R.U.M.S. was inspired by the Tremor, a MIDI drum set made by the DJ AFISHAL. The Tremor and D.R.U.M.S use sensors to detect impacts on a drum face and subsequently send electrical signals to corresponding sensors for interpretation by a computer. As well as the drum hit triggering a sound from a MIDI standpoint, the drum hit also triggers a light change of the localized drum. This report will include the design process, hardware, software, and other information needed to design the D.R.U.M.S. from both a mechanical and electrical standpoint.

Mechanical

The D.R.U.M.S. consists of eight individual D.R.U.M.S. modules, connected by a PVC frame. Using a variety of connectors and lengths of PVC pipe, the D.R.U.M.S. take a trapezoidal shape where the user stands in the middle of the drum set.

Electrical

Regarding the electrical components of the D.R.U.M.S., the drum set consists an Arduino Leonardo, as well as eight individual yet identical D.R.U.M.S. modules. The purpose of these modules is to send an electrical signal to the master Arduino Leonardo for interpretation by the computer and ultimately the Ableton software, as well as control the RGB light strips attached to each module.

D.R.U.M.S. Module

As stated prior, each D.R.U.M.S. module is the same, and each acts as a different drum head for the Arduino Leonardo. The components for the module is listed below:

• (1) – Arduino Nano (Through-Hole)
• (1) – Female Headers (Through-Hole)
• (2) – 10k Potentiometer (Through-Hole)
• (4) – 2-pin Terminal Block
• (1) – 3-pin Terminal Block
• (3) – TIP120 Transistor (SMD)
• (1) – 1 MΩ Resistor (SMD)
• (3) – 220 Ω Resistor (SMD)
• (1) – Piezoelectric Sensor (Separate Wire)

The schematic shown in Figure III.A.1 is the wiring of the module. The function of the module is rather simple—the piezoelectric sensor is triggered with the drum is hit, sending an electrical signal to an analog pin of the Arduino Nano present on the module. When this signal is detected, the Arduino sends a digital signal to the Arduino Leonardo, as well as changes the color displayed by its RGB light strip. The potentiometers are present to act as the color selection tool. One of the potentiometers is used to choose the color of the RBG lights when the module is inactive, and the other potentiometer chooses the color when the drum is hit.

Arduino Leonardo

In this system, the Arduino Leonardo acts the bridge between the D.R.U.M.S. modules and the PC running the Ableton software. The benefit of the Arduino Leonardo is the ATmega32U4, a microchip equipped with a USB transceiver. This significantly reduces the difficulty of programming the Arduino as the hurdle of needing to perform a device firmware update on devices such as an Arduino Nano can be difficult and certainly is time consuming.