The OSAM-1 robot arm is designed to rendezvous with a satellite in orbit, grasp it, and refuel it. I provide robotics analysis for the dexterous robot arm including verifying robot arm performance requirements for on-orbit operations. 

I also provided support for the integration and testing of various robot arm components. I have extensive experience with writing test plans for flight units and characterizing motors that will be used to build these robot arms. The test plans and procedures are used to validate the performance of the arm in ambient tests, thermal vacuum, and random vibration environments. I also have gained experience integrating and testing printed circuit boards (PCBs) that are critical to the function of the arm as a system. 

I was the primary electro-mechanical engineer for the development of this large 2-axis rotation test platform for OCI. The engineering test unit (ETU) of OCI is shown here installed on our mechanism. The mechanism allows for +/-110 degrees of rotation in azimuth and -90 and +30 degrees of rotation in elevation. I designed the drive system and selected motors and optical encoders for the system. I also wrote the Labview code that allowed the scientists to rotate OCI and perform stray light testing on the instrument. The mechanism allows the roughly 800lb OCI to rotate to +/-0.001 degrees of the desired target. The mechanism was also used to test the flight model of OCI and has been a critical part of the testing procedures for the OCI scientists. 

During my time working in the Center for Advanced Manufacturing (CAM) I primarily worked on a robot arm for a mobile manipulator. The goal of the project was to program the mobile manipulator to move around a manufacturing setting and perform ultrasonic non-destructive testing on manufactured parts. I used ROS and python to program the UR5 robot arm and generate motion paths. The robot arm was equipped with a depth camera at the end effector that allowed me to create point clouds of the environment. The point cloud was used to generate motion paths that would scan the part and allow the ultrasonic sensor to return data regarding areas of the part that may have cracks or fractures not visible to the human eye.  

I have considerable experience with designing printed circuit boards. I designed this circuit board to control a 2-axis heliostat. The circuit board has H-Bridges to drive stepper motors at various speed and torque. The heliostat controller also used feedback from a sun sensor and encoder to rotate the heliostat precisely and point at the sun when desired. I used EAGLE for this design and picked up a lot of detailed knowledge about board design from other engineers at Goddard Space Flight Center.

I also was able to gain experience as an embedded software engineer during this project. I programmed the on-board microcontroller to control the lunar heliostat and communicate with other critical systems in the heliostat. I wrote the controller program in C using a 32-bit ARM microcontroller.

Below is a reaction wheel I designed while working for the Attitude Control Systems branch at NASA Goddard. Most CubeSat reaction wheels are thick and have a high height to diameter aspect ratio. The 3-axis reaction wheel assembly I designed addresses these issues and allows for larger payload volume within the spacecraft while still maximizing torque output. Volume and mass efficiency combined with the need to survive launch loads drove this wheel design. The motor and reaction wheel are shown below undergoing vibration testing. 

I developed a roll stabilizing platform for a NASA Goddard Radiometer and Synthetic Aperture Radar (SAR) system during their test flights in a DHC-6 Twin Otter aircraft. I designed the structure and electro-mechanical system shown in the pictures here. By implementing an Inertial Measurement Unit (IMU) for attitude feedback and linear actuator for actuation, the mechanism keeps the platform level throughout the science flights. The platform is still in use by the microwave instruments branch at Goddard Space Flight Center and will be used for upcoming science flights around the US.

Below is a project I worked on to create a controller for a A1 Unitree robot dog. I developed a QP and MPC controller for the quadruped robot. The MPC controller was used for walking, running, and climbing stairs. The model below was built in Simulink using the optimization and multibody toolboxes. The system was modeled as a single rigid body with forces acting at the contact locations of the feet with the ground. The inverse jacobian for each leg was used to convert the force required to stabilize the robot to torques for each of the joints.  

Below is my design for a dual axis rotation controller for a large Unmanned Aerial Vehicle (UAV). The project was designed for our clients at the Army Research Lab (ARL) my team and I worked to meet the requirements set. I designed the electromechanical system and mechanisms for this project. The system has gearmotors for each axis and magnetic encoders provide feedback to the system. The "claw" mechanism was used to rotate the sabot during flight and release the payload when as the user desired. I also was able to get experience with carbon fiber lay up and the learned some of the tricks to creating stiff and beautiful carbon fiber structures. 

I was a very active member of the Design, Build, Fly team at Johns Hopkins and the president of the club my senior year. I was extremely passionate about this club and spent a significant amount of time not only building the model aircraft, but the club itself. The club was no longer operating at Hopkins when I entered as a freshman. I led the effort to get the team up and running again and wanted to create an opportunity in which my fellow engineering students and I could put our classroom skills into practice.

On the technical side, I focused mainly on aircraft structures where I was responsible for the structural design and manufacturing of the aircraft. I also developed a battery testing procedure that allowed us to experiment with propellers and thrust output. These are some of our prototypes from the 2017 competition in Tuscon, AZ. We used a laser cutter to cut almost all of our wood and a strip of carbon fiber to bolster the wing.