# 6th Annual Senior Design Expo Showcases 10 Electrical Engineering Projects

29 Electrical Engineering students participated in Columbia Engineering’s 6th Annual Senior Design Expo. With topics ranging from sports to music, from animals to physical therapy, these finished projects culminated a yearlong process of teamwork, science and dedication.

The 2019 Senior Design Expo, took place at Columbia University’s Roone Arledge Auditorium in May 2019, and attracted hundreds of visitors, including faculty, deans, staff, students, and industry leaders.

Students worked closely with their faculty advisors throughout the development of their projects, from design to implementation which provided students with opportunities to be creative and solution-oriented, propelling them to be successful in their professional lives as they graduate from the Electrical Engineering Department.

Baseball Strike Zone Delineator

Joon Mo Park built a baseball strike zone delineator. Contrary to the popularly held notion that the baseball strike zone is rectangular and is ﬁxed, the strike zone is actually constantly changing as the batter is making movements to hit the baseball and has a shape of a pentagonal prism. The proposed delineator calculates for the position of the strike zone using input images obtained from the two set-up cameras and using digital image processing techniques. The delineator aims to aid the umpires in the process of determining whether a pitch is a strike or a ball by providing them an environment where they can compare their calls with those calculated from the algorithm.

Education Logic Blocks

Leah Feuerman, Jacqueline Napolitano, Sayaan Nawaz, and Jackson Welles worked with Columbia Secondary School to develop an educational game to teach students the fundamentals of computer hardware and logic. This project allows students to build their own logic statements using their hands, and see the results with both a computer interface and the structures they build.

Using physical electronic logic blocks, students discover the principles of Boolean algebra as performed on binary signals. Each interconnecting block contains a simple circuit to deﬁne their functionality. Individual blocks will include AND, OR, and INVERT gates, INPUT and OUTPUT variable blocks, TIMER and binary COUNTER circuits, as well as a POWER supply block. A GUI presents the students with logic prompts and allows them to deﬁne the INPUT blocks based on the riddle they are solving.

Class D-Amplifier

Chase Stine and Jay Mok built a built-from-scratch amplifier with a custom-built power supply unit. Uses class-D amplification topology, a single positive power supply, has volume control, pre-amplification, feedback, over-current protection and multiple speaker drive capabilities. Can be connected via Bluetooth, phone audio jack, computer audio jack, or other audio output devices such as MIDI keyboards or electric instruments.

Broken Electronics: An IoT Fracture Boot, Walker and Screen

Ryan Davies, Shamirah Tillman, and Mohammad Khojah built an IoT fracture boot. After breaking a bone, the process of recovery is often delayed by putting too much weight on the affected area. Our project seeks to solve this common problem by providing real-time feedback to the patient and useful metrics to their physician. This was accomplished through the use of specialized sensors which read how much weight was placed in critical areas in order to display this information using LEDs and sent it to a database using Wi-Fi. Additional features included fall detection through use of an accelerometer that sent a message to the relevant caregivers. These improvements allow for recovery to be both safer and more effective.

Real-Time Frequency Stabilization and Control Systerm

William Mauro built a real-time frequency stabilization and control sysyem. Discrete analog oscillators are a common sound source in both modern and historic music sound synthesizers, however they have an unfortunate tendency to drift out of tune. In part, this frequency drift can be attributed to the varying characteristics of discrete solid-state components which intrinsically depend on the ambient temperature of the circuit. Additionally, over time, aging circuit elements may deviate from their listed specifications, and a once-calibrated oscillator may no longer behave predictably. In order to combat these difficulties, he developed a novel feedback control system whereby the frequency of an oscillator is continuously measured and adjusted in real-time by digital means in order to maintain precision tuning for any analog oscillator, no matter how unstable.

Pet Minder

Benjamin Brigman,Asher Goldfinger, Anthony Gutierrez, and Moises Pena Jr. built an automated food and water dispenser. The idea for Pet-Minder is to create a system of modules that can identify a pet in a multiple pet environment, attributing a particular diet, monitor movements, and relay information about each one to a phone application. This is achieved by the construction of automated food and water dispenser and a “doggy-door” module alongside RFID tag communication with multiple microcontrollers.

Qwit Equalizer

Jose Rubianes built a Qwit equalizer. Many analog equalizers have only 3 bands, and offer relatively crude control over their frequency response. If one wanted to have ﬁner-grained control over real-time audio, their current options are limited to large rack-mounted DSP units, expensive parametric equalizers tailored for profession applications, or software plugins. There is a current lack of affordable options for prosumers who want ﬁner-grained control over real-time audio. The goal of this project was to create a small and relatively inexpensive semi- parametric equalizer to ﬁll this niche.

The QWit allows the user to program nearly any arbitrary frequency response. Despite being digitally programmable, all equalization is done using analog ﬁlters, avoiding the delay associated with digital signal processing.

Fully Integrated Power

Peter Frey, Michael Harriss, Johnny Li, and Max Moeller built a flow battery and inverter. Exploration of a possible design for a modular solution to accessing alternative energy storage technologies. The project includes DC/AC conversion of the output, charging capabilities from the standard wall outlet, phase synchronization between each device, and feedback control system to maintain output load.

Choatic DJ

Ryan Arteaga, Jinglei Guo, Ishraq Khandaker, and Hongyi Li modified an electrica guitar wah-wah pedal so as to be controlled automatically. The controller is a circuit that produces a chaotically varying voltage, which they processed using an Ardiuno micro controller, whech then dorve a physical motor. The motor was connected to the wah-wah pedal and it turned the knob on the pedal that adjusts the sound of the effect.

Dual-Axis Interactive Base

• Matthew Barlow, Christopher Bhim, Marielle Jones, Luis Perez, and Neel Singal built a target game played between a human and a computer. The game consists of a platform that can rotate and tilt, with a toy electric train circling around it. Play starts with the human dropping a ping pong ball through a chute above the rotating platform. If it is the human’s turn, he/she tries to drop the ball at the correct moment to have it bounce off the platform and into a cup carried by the circling train. If it is the computer’s turn, it uses its camera to track the ball dropped by the human, locate the train and predict its path; it then tilts and rotates the platform to make the ball bounce into the cup.

-By Eliese Lissner

500 W. 120th St., Mudd 1310, New York, NY 10027    212-854-3105