Julian Rene Alvarez
Take a look around.
Work 4+ Years ago
Early Engineering Work
3DR
Open Source Autopilots
Life After Gravity
As the commercial offshoot of an online Open Source project started in the early 2000s, 3D Robotics helped incubate the earliest hobby UAVs through the website DIY Drones.
A slow progression from a hobby to consumer grade products has led 3DR to develop the SOLO: Smart Drone that carries a full linux computer as well as an updated Pixhawk 2.
Interested primarily in the open source nature of these projects, I joined the team to experience the later stages of a product development cycle with the SOLO smart drone.
SpaceX
Reusable Rockets
Hypersonic Gridfin System
In order to fulfill intentions of a fully reusable rocket, SpaceX has been implementing gradual improvements to the Falcon 9 launch vehicle to provide it with Return to Launch Site capabilities. Additional fuel, landing legs, deep throttling engines, and most recently, a hypersonic gridfin system.
Used to help control the lift generated by the first stage of the Falcon 9 during its hypersonic re-entry trajectory, the 4 grid fins are stowed during ascent and are deployed when the stage reaches the apex of its flight in space.
As Responsible Engineer for three Outer Mold Line (OML) components of the gridfin assembly I performed Static Stress, Fatigue, and Nonlinear Analysis in Femap Nastran while Solid modeling in Siemens NX. Production drawings were then drafted per AMSE-Y-14.5-2009 and GD&T.
Recovery Technique
Shortly after main engine cutoff and second stage separation the Falcon 9's first stage is travelling at Mach 5 at an altitude of >100 km. To recover the 140 foot long ~30 Ton stage it is first flipped 180 degrees with cold gas thrusters and then performs a boostback burn. While in the sparse upper atmosphere it deploys the gridfins for reentry guidance. A brief entry burn slows the vehicle further but it continues to coast to the targeted landing location bleeding speed through aerodynamic friction. A few hundred feet from the ground the center engine is reignited for a suicide burn that slows the vehicle to zero velocity for a safe touchdown.
ORBCOMM 2
Following numerous partially successful barge landing attempts, on December 21st, 2015 SpaceX performed the fully successful first stage recovery with a newly updated Falcon v1.2 Full Thrust.
Recovered First Stage
After enduring both ascent and reentry aerodynamic heating the thermal protection system on the fins and surrounding first stage was severely ablated.
Terrasoar: Senior Capstone
Electric Air-Ground Vehicle
Concept to Reality
Selected as the lead engineer for Arturo Vidich's TerraSoar project, I was responsible for taking his intentions for an electric aircraft/ground vehicle and turning them into a reality. Working together with a fellow ME, Ewan Kay, TerraSoar became our Senior Capstone Project. Many design iterations later the vehicle had become increasingly more defined. These designs were tested in the fom of two scale models as well as numerous software models of the aircraft.
Developing an aircraft concept requires detailed analysis, which in the case of the TerraSoar began with sizing studies and performance estimation. Stability analysis performed in XFLR5 was then used to more accuratley size the flying surfaces. Finally, CFD and FEA were used to verify the design of TerraSoar, with focus on the forward wing, or canard. The canard design was detailed and finalized by mid March and partially constructed by the end of the semester. I was forced to leave the project after moving to the west coast.
Additional Graphics can be found here
Cooper Union
Educational Engineering Projects
Hail Mary
Folding hexacopter with spring loaded arms. Short term goal is low altitude and low velocity deployment and stabilization. Hopes of deploying at higher altitudes with a supersonic launch thereafter.
Currently performing initial sizing and frame/gimbal design for 3D printing.
Independent
September 2014 - Ongoing
Designed in Solidworks.
Launch profile prediction in Matlab.
MicroQuad
Small format Quadrotor designed for first person view flying (FPV). 10in. Rotor to Rotor when deployed, arms fold for transport. Inspiration for frame structure came from nature as well as visualization of shear stresses.
Cooper Union
Spring 2014
All components custom machine from Delrin using a manual Mill and Laser Cutter.
Designed in AutoCAD and Solidworks.
3 Stage Axial Compressor
Loosely based on GE J85-5 compressor stages
CFD predicted 9:1 compression ratio
16,000 RPM @ 1200 HP
Simulated with sliding mesh interfaces
Cooper Union
Spring 2013
Designed for Introduction to CFD final project
CAD model in Solidworks, meshing in Hypermesh, CFD in Ansys Fluent
Fliegel
First Person View Flying Wing UAV
Mounts GoPro2 Camera and Video TxIndependent
Summer 2012
Breaks down into 3 pieces to easily fit into a Pelican case
Designed in SolidWorksFolding Quadrotor Frame
Asymmetric frame design for aerial photography
IR obstacle avoidance capable
Maiden flight video here
Cooper Union
Spring 2012
Prototyped out of lasercut Delrin Plastic
Designed in AutoCAD and SolidWorksAeolus UDMA
Vertical takeoff and landing UAV
Awaiting further design iterations
Cooper Union
Summer 2011 - Ongoing
CNC Prototyping started
Designed in SolidWorks
Research Quadrotor Frame
Modular frame design for misson adaptation
1 kW combined power at full throttle
15-20 minute flight timesMaiden flight here
Cooper Union
Spring 2011
Designed in AutoCAD and SolidWorks
Early Work
Educational Engineering Projects
Guardian 2.0
Design optimized from orginal Guardian
Rocket launched vertical takeoff UAV
Accelerated deployment lowers response timeLake Brantley HS
2009Prototyped out of hotwire cut EPP Foam, 3-D printed Parts, and Carbon Fiber
Designed in AutoCAD
Guardian
Rocket launched vertical takeoff UAV
Accelerated deployment lowers response timeLake Brantley HS
2008Prototyped out of hotwire cut EPP Foam, 3-D printed Parts, and Carbon Fiber
Designed in AutoCADPhantom 2.0
Design optimized from orginal Phantom
Ducted fan VTOL UAV with detachable wings
Designed for long and close range operationsLake Brantley HS
2007Prototyped from hotwire cut EPP foam
Designed in AutoCAD
Phantom
Ducted fan VTOL UAV with detachable wings
Designed for long and close range operations
Teague MS2006
Prototyped from hotwire cut EPP foam
Designed in AutoCAD
Copyright 2016 Julian R. Alvarez