Mechanical Design Engineer · New York City

Ezra Rosenfeld

Design, analysis, and fabrication of physical products.

An independent mechanical design engineer who takes physical products from first concept to working hardware — mechanism and mechatronic design, structural and thermal analysis, additive and traditional manufacturing, and the software tooling that speeds it all up.

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01 — Profile

I'm a mechanical design engineer who works across the full arc of a physical product — concept and mechanism design, parametric CAD, structural and thermal analysis, and prototyping through to production. I move easily between the CAD seat, the simulation loop, and the shop floor.

That breadth shows up in the work: a patented consumer product of my own, production hardware and analysis for electric-mobility and clean-energy companies, and prototypes in the research lab. A decade of hands-on fabrication means the parts I draw are the parts that get built — I started learning CAD at eleven and taking freelance work at fifteen.

When a workflow is slower than it should be, I build the tool to fix it — CAD add-ins, generative-geometry pipelines, and small automations. I'm drawn to problems that sit between mechanical design, software, and manufacturing.

Role

Independent design consultant

Focus

Product design, analysis & fabrication

Also runs

Rosenfeld Studios LLC

Based

New York City

02 — Timeline

The path here.

Age 7

Decided on mechanical engineering

Age 11

CAD

Age 13

3D printing & prototyping

Age 15

Carpentry & freelance work

2023

Age 18

BA Physics, Yeshiva · JOCO

2025

Lead Mech. Design Engineer, Popwheels

2026

ChargeBot · MS, Columbia SEAS

03 — Experience

Professional experience.

Mechanical design and product development across electric mobility, clean energy, and consumer hardware.

May 2026 — Present

Active

Mechanical Design Engineer

ChargeBot — Bethesda, MD

Leading end-to-end product development of ChargeBot's next-generation off-grid, solar-powered EV charging system to UL 2743 standards: large-format RIM, structural sheet metal, integrated thermal management, and enclosure durability validated against transit and environmental testing.

UL 2743RIMSheet metalThermalFEA / CFD

Jun 2025 — Present

Active

Lead Mechanical Design Engineer

Popwheels — New York, NY

Led hardware engineering across three product generations of the PW-IA inverter-adapter and engineered a UL 1487-compliant battery charging cabinet with an active pressurization seal and suppression architecture. Ran full-scale destructive testing and resolved fleet-wide decommissioning risks across 100+ battery stations.

UL 1487Battery cabinetsPressurization sealDestructive testing

Aug 2023 — May 2025

Mechanical Engineer

JOCO — New York, NY

Digitized critical legacy components into high-fidelity CAD assemblies under rapid turnaround, enabling immediate tooling reorders and vendor production, and prototyped functional residential fire-suppressive battery enclosures from conceptual sketches through machined, bench-tested units.

CAD digitizationPrototypingBattery enclosuresTooling

04 — Selected Projects

Things I've designed & built.

A mix of production hardware, engineering tooling, and personal builds. Tap any project for detail.

P-01

Airport Off-Grid Charging System

Landscaping robots · full mechanical design

An off-grid, solar-powered charging station that keeps autonomous landscaping robots running at airports and large grounds. I lead the full mechanical design of the second generation — internal packaging, thermal CFD, structural FEA, and design to IP54 and UL 2743.

Patent Pending

P-02

SnapMount

Self-locking vertical bike mount

A compact, tool-free vertical bike storage system: a spring-loaded snap-lock clamps the wheel at the rim, installed with adhesive backing — no drilling, no fasteners.

P-03

Solar Array Secure Packaging

Packaging & logistics design

Transit-safe packaging for the charging system and its solar arrays: custom crating that protects fragile panel glass from shipping and handling damage, optimized to a standard 48×40″ pallet.

NYC Pilot

P-04

PW-IA Inverter Adapter

Popwheels · clean cart power

A battery inverter-adapter that turns Popwheels swappable batteries into silent, emissions-free power for NYC street-food carts — piloted by the city in place of gas generators.

Project Lead

P-05

Iridescent Butterfly

Moth Quantum · brand animation

An iridescent butterfly brand animation for Moth Quantum, with the wing color generated using quantum computing. I ran project management and delivery; a collaborating artist led the 3D and shader work.

P-06

Wire Harness Add-in

Fusion 360 · Python add-in

A complete Fusion 360 add-in for wire-harness generation, built to Onshape-parity feature coverage — structured harness routing and modeling in a workflow that lacked it.

P-07

Parametric Robot Dog

Generative CAD · code-driven geometry

A fully parametric robot-dog model built in a code-CAD environment, with multi-format exports for downstream fabrication and simulation.

P-08

Calendar Commute

Chrome extension · Manifest V3

A Chrome extension that reads Google Calendar and generates commute time-blocks automatically via the Maps API — architecture through a V2 spec.

05 — Capabilities

What I bring to the bench.

Design & CAD

Fusion 360
SolidWorks
Autodesk Inventor
Parametric & code-CAD
GD&T

Manufacturing

3D printing & additive
Sheet-metal fabrication
Injection & RIM molding
CNC machining & toolpaths
Design for manufacture

Simulation & Testing

FEA & CFD analysis
Hardware & environmental testing
Transit, drop & vibration validation
Root-cause analysis
Statistical validation

Standards & Compliance

UL 1487 · 2743 · 62368-1
IP-rated sealing
EMI & environmental gaskets
ASME Y14.5
ANSI Z535.6

Systems & Integration

Enclosure & cabinet design
Thermal management
Battery-swap systems
Product feasibility & cost modeling
Reverse engineering

Automation & Code

Python
CAD API add-ins
Generative geometry pipelines
Chrome extensions
Workflow automation

06 — Education & Beyond

Education

MS, Mechanical Engineering

Columbia University, SEAS

Aug 2026 — Dec 2027

BA, Physics

Yeshiva University

Aug 2023 — May 2026 · Dean's List

Self-taught engineer

CAD · fabrication · advanced manufacturing

Hands-on since age 11

Beyond engineering

Rosenfeld Studios LLC

Founder and photographer — a creative practice run alongside the engineering work.

Teen crisis helpline

Co-founded a crisis helpline supporting teens.

Cycling & making

Central Park rides, espresso, and a steady stream of personal hardware builds.

07 — Contact

Let's build something.

Open to mechanical design and product roles, research, hardware collaborations, and internships. The fastest way to reach me is email.

ezrarosenfeld12@gmail.com LinkedIn