Coursework

6.484/6.832 (Sensorimotor Learning, Underactuated Robotics) - Spring 2022

For the final project in these classes, we explored finding reset controllers for training episodic reinforcement learning agents. As the agent explores the environment, we build a polynomial system model, and use a sum-of-squares optimization to find a backward policy. We allow the reinforcement learning agent to take actions until we think the agent will leave the region of attraction of the reset policy, where we then engage the backward policy to bring the agent back to the origin. By cycling between the forward and backward policies, we hoped to expand the region of attraction while also allowing the RL agent to learn.

6.08 (Introduction to EECS via Interconnected Embedded Systems) - Spring 2022

For this project, developed a modular, music-streaming system similar to Sonos. Users are able to queue songs from a database of downloaded songs, manipulate the queue, and are able to download new songs from YouTube. The currently playing song is streamed from a central server to individual clients at CD quality. Each client consists of an ESP32, I2S DAC, and class D audio amplifier. I was responsible for the electrical design, firmware, and server-to-client music streaming.

Github: https://github.com/gregoryxie/nicer-rack

2.009 (The Product Engineering Process) - Fall 2021

Our team developed an aisle chair to assist wheelchair users into airplane seats, reducing the amount physical interaction between wheelchair users and flight attendants. The chair is completely mechanical, and moves users into the airplane seat adjacent to the aisle. I was responsible for the winch system and footrest on the final design.

6.843 (Robotic Manipulation) - Fall 2021

In this project, we explored throwing darts with a 7-DOF robot arm in simulation. We formulate an optimization problem to find the release pose and velocity of the dart, and implement rudimentary aerodynamics to evaluate our system in simulation.

2.671 (Measurement and Instrumentation) - Spring 2021

In this project, I explored the relationship between temperature and the viscoelastic properties of string cheese. I test string cheese in a homemade three-point bending setup, and find that while the stiffness of the cheese changes drastically, the viscoelastic time constant does not.

2.151 (Advanced System Dynamics and Control) - Fall 2020

In this project, we tried to control a 3-DOF gyroscope. I was responsible for the controller, for which I tried to implement a velocity-based, gain-scheduled LQR controller. We designed and simulated our system in MATLAB and Simulink.

6.101 (Introductory Analog Electronics Laboratory) - Spring 2020

For this project, we designed an microcontroller free curve tracer. The tracer can find the characteristic curves of BJTs and two terminal devices. It automatically determines if the device under test is a two or three terminal device. If the DUT is a three terminal device, it also detects the type and orientation of the BJT. This project was done completely in simulation (LTspice), meaning that the design will probably not transfer to real life without adjustments.